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Sample records for chronic uremic rats

  1. Insulin resistance in uremia: Insulin receptor kinase activity in liver and muscle from chronic uremic rats

    SciTech Connect

    Cecchin, F.; Ittoop, O.; Sinha, M.K.; Caro, J.F. )

    1988-04-01

    The authors have studied the structure and function of the partially purified insulin receptors from liver and skeletal muscle in a rat model of severe chronic uremia. {sup 125}I-insulin binding was higher in the liver from uremic rats when compared with ad libitum- and pair-fed controls. Furthermore, the ability of insulin to stimulate the autophosphorylation of the {beta}-subunit and insulin receptor kinase activity using Glu{sup 80}, Tyr{sup 20} as exogenous phosphoacceptor was increased in the liver of the uremic animals. The structural characteristics of the receptors, as determined by electrophoretic mobilities of affinity labeled {alpha}-subunit and the phosphorylated {beta}-subunit, were normal in uremia. {sup 125}I-insulin binding and insulin receptor kinase activity were similar in the skeletal muscle from uremic and pair- and ad libitum-fed animals. Thus the data are supportive of the hypothesis that in liver and muscle of chronic uremic rats, insulin resistance is due to a defect(s) distal to the insulin receptor kinase.

  2. Insulin resistance in uremia. Characterization of lipid metabolism in freshly isolated and primary cultures of hepatocytes from chronic uremic rats.

    PubMed Central

    Caro, J F; Lanza-Jacoby, S

    1983-01-01

    We have studied the mechanism(s) of hyperlipidemia and liver insulin sensitivity in a rat model of severe chronic uremia (U). Basal lipid synthesis was decreased in freshly isolated hepatocytes from U when compared with sham-operated ad lib.-fed controls (alfC). Basal lipid synthesis in pair-fed controls (pfC) was in between U and alfC. Similarly, the activity of liver acetyl CoA carboxylase, fatty acid synthetase, citrate cleavage enzyme, malate dehydrogenase, and glucose-6-phosphate dehydrogenase was diminished in U. Muscle and adipose tissue lipoprotein lipase was also decreased. Insulin stimulated lipid synthesis in freshly isolated hepatocytes from alfC. Hepatocytes from U and pfC were resistant to this effect of insulin. To ascertain if the insulin resistance in U was due to starvation (chow intake 50% of alfC) or to uremia itself, the U and pfC were intragastrically fed an isocaloric diet via a Holter pump the last week of the experimental period. Hepatocytes from orally fed U and pfC were also cultured for 24 h in serum-free medium. While freshly isolated and cultured U hepatocytes remained insulin resistant, those from pfC normalized, in vivo and in vitro, when they were provided with enough nutrients. Conclusions: (a) Hyperlipidemia in uremia is not due to increased synthesis, but to defect(s) in clearance. (b) Insulin does not stimulate lipid synthesis in uremia. This finding, along with our recent demonstration that insulin binding and internalization are not decreased in the uremic liver, suggests that a post-binding defect(s) in the liver plays an important role in the mechanism(s) of insulin resistance in uremia. (c) Cultured hepatocytes from uremic rats remain insulin resistant. This quality renders these cells useful in studying the postinsulin binding events responsible for the insulin-resistant state in the absence of complicating hormonal and substrate changes that occur in vivo. PMID:6350367

  3. Acid-Base Balance in Uremic Rats with Vascular Calcification

    PubMed Central

    Peralta-Ramírez, Alan; Raya, Ana Isabel; Pineda, Carmen; Rodríguez, Mariano; Aguilera-Tejero, Escolástico; López, Ignacio

    2014-01-01

    Background/Aims Vascular calcification (VC), a major complication in humans and animals with chronic kidney disease (CKD), is influenced by changes in acid-base balance. The purpose of this study was to describe the acid-base balance in uremic rats with VC and to correlate the parameters that define acid-base equilibrium with VC. Methods Twenty-two rats with CKD induced by 5/6 nephrectomy (5/6 Nx) and 10 nonuremic control rats were studied. Results The 5/6 Nx rats showed extensive VC as evidenced by a high aortic calcium (9.2 ± 1.7 mg/g of tissue) and phosphorus (20.6 ± 4.9 mg/g of tissue) content. Uremic rats had an increased pH level (7.57 ± 0.03) as a consequence of both respiratory (PaCO2 = 28.4 ± 2.1 mm Hg) and, to a lesser degree, metabolic (base excess = 4.1 ± 1 mmol/l) derangements. A high positive correlation between both anion gap (AG) and strong ion difference (SID) with aortic calcium (AG: r = 0.604, p = 0.02; SID: r = 0.647, p = 0.01) and with aortic phosphorus (AG: r = 0.684, p = 0.007; SID: r = 0.785, p = 0.01) was detected. Conclusions In an experimental model of uremic rats, VC showed high positive correlation with AG and SID. PMID:25177336

  4. Cardiac effect of vitamin D receptor modulators in uremic rats.

    PubMed

    Mizobuchi, Masahide; Ogata, Hiroaki; Yamazaki-Nakazawa, Ai; Hosaka, Nozomu; Kondo, Fumiko; Koiwa, Fumihiko; Kinugasa, Eriko; Shibata, Takanori

    2016-10-01

    Vitamin D receptor (VDR) modulators (VDRMs) are commonly used to control secondary hyperparathyroidism (SHPT) associated with chronic kidney disease, and are associated with beneficial outcomes in cardiovascular disease. In this study, we compared the cardiac effect of VS-105, a novel VDRM, with that of paricalcitol in 5/6 nephrectomized uremic rats. Male Sprague-Dawley rats were 5/6 nephrectomized, fed a standard diet for 4 weeks to establish uremia, and then treated (intraperitoneally, 3 times/week) with vehicle (propylene glycol), paricalcitol (0.025 and 0.15μg/kg), or VS-105 (0.05 and 0.3μg/kg) for 4 weeks. In uremic rats, neither VDRM (low and high doses) altered serum creatinine and phosphorus levels. Serum calcium was significantly higher with high dose paricalcitol compared to sham rats. PTH levels were significantly decreased with low dose paricalcitol and VS-105, and were further reduced in the high dose groups. Interestingly, serum FGF23 was significantly higher with high dose paricalcitol compared to sham rats, whereas VS-105 had no significant effect on FGF23 levels. Left ventricle (LV) weight and LV mass index determined by echocardiography were significantly suppressed in both high dose VDRM groups. This suppression was more evident with VS-105. Western blotting showed significant decreases in a fibrosis marker TGF-β1 in both high dose VDRM groups (vs. vehicle) and Masson trichrome staining showed significant decreases in cardiac fibrosis in these groups. These results suggest that VS-105 is less hypercalcemic than paricalcitol and has favorable effects on SHPT and cardiac parameters that are similar to those of paricalcitol in uremic rats. The cardioprotective effect is a noteworthy characteristic of VS-105.

  5. Resistant starch alters gut microbiota and reduces uremic retention solutes in rats with adenine-induced chronic kidney disease

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chronic kidney disease (CKD) is characterized by the reduced ability to void urine, leading to accumulation of waste products in the body. Recently, it has been observed that patients with CKD have an altered gut microbiome. This may in part be due to reduced fiber intake. Patients with CKD are ofte...

  6. Trabecular bone volume and osteoprotegerin expression in uremic rats given high calcium.

    PubMed

    Rianthavorn, Pornpimol; Ettenger, Robert B; Salusky, Isidro B; Kuizon, Beatriz D

    2010-11-01

    Calcium (Ca)-containing phosphate binders have been recommended for the treatment of hyperphosphatemia in children with chronic kidney disease. To study the effects of high Ca levels on trabecular bone volume (BV) and osteoprotegerin (OPG) expression in uremic young rats, a model of marked overcorrection of secondary hyperparathyroidism was created by providing a diet of high Ca to 5/6 nephrectomized young rats (Nx-Ca) for 4 weeks. The results of chondrocyte proliferation and apoptosis, osteoclastic activity, OPG expression and BV were compared among intact rats given the control diet, intact rats given a high Ca diet and 5/6 nephrectomized rats given the control diet (Nx-Control) and the high Ca diet (Nx-Ca). Ionized Ca levels were higher and parathyroid hormone levels were lower in Nx-Ca rats than in the other groups. Final weight, final length and final tibial length of Nx-Ca rats were significantly less than those of the other groups, although the length gain did not differ among the groups. The hypertrophic zone width was markedly enlarged in Nx-Ca rats. Chondrocyte proliferation rates did not differ among the groups, whereas osteoclastic activity was decreased in Nx-Ca rats compared with the Nx-Control animals. The OPG expression and BV were increased in Nx-Ca rats compared with the Nx-Control rats. Increased BV should improve bone strength, whereas disturbance of osteoclastogenesis interferes with bone remodeling. Bone quality has yet to be determined in high Ca-fed uremic young rats.

  7. [Effect of growth hormone and calcitriol on the growth plate in uremic rats].

    PubMed

    Amil, B; Fernández-Fuente, M; Santos, F; Rodríguez, J; Díaz-Tejón, L; García, E; Carbajo, E

    2003-01-01

    This study analyzed the modifications induced by growth hormone (GH) and/or calcitriol treatments in the growth plate of growth retarded uremic rats. Four groups of 5/6 nephrectomized rats were studied: untreated (U), treated with GH (U + GH), treated with calcitriol (U + D), treated with GH and calcitriol (U + GH + D). Treatments were given intraperitoneally during the second week of renal failure. Uremic groups were compared with sham-operated rats fed ad libitum (C) or pair-fed with U (CP). In comparison with C and CP, histomorphometric analysis of tibial proximal ends of U group showed decreased bone formation, as estimated by osseous front advance (OFA), elongation of growth cartilage and its hypertrophic zone, and decreased size of most distal chondrocytes. The U + D group tended to normalize growth cartilage height, and that of its hypertrophic zone, as well as the size of chondrocytes. In U + GH group OFA improved and chondrocyte size became normal, but growth cartilage remained elongated. Similar results were found in the U + GH + D group. These findings indicate that, in chronic renal insufficiency, the beneficial effect of GH on growth is not associated with normalization of growth cartilage morphology and that calcitriol facilitates chondrocyte maturation. When given together the effect of GH prevails.

  8. Metabolic bone disease in chronic renal failure. I. Dialyzed uremics.

    PubMed Central

    Huffer, W. E.; Kuzela, D.; Popovtzer, M. M.

    1975-01-01

    Garner and ball's point counting technic was used to compare metabolic bone disease in dialyzed and nondialyzed uremic patients. Histologic measurements of bone from dialyzed and nondialyzed uremic patients dying between 1966 and 1971 showed that dialyzed patients have quantitatively more severe bone resorption, distortion of trabecular architecture and mineralization defects. Mineralization defects become more severe as the duration of dialysis increases but are not related to serum calcium and phosphorus levels. Bone volume in both groups is normal or increased and in dialysis patients increases in proportion to the elevation of serum phosphorus. Mean serum phosphorus and calcium levels, bone volume, and volume: surface ratios all decreased in dialysis patients between 1966 and 1971, while bone resorption and mineralization defects did not change. These results suggest that lowering of serum phosphorus without increasing serum calcium may aggrevate the uremic bone disease by reducing bone volume without improvement of mineralization and resorption defects. Images Fig 1 PMID:1119535

  9. High-phosphorus diet maximizes and low-dose calcitriol attenuates skeletal muscle changes in long-term uremic rats.

    PubMed

    Acevedo, Luz M; López, Ignacio; Peralta-Ramírez, Alan; Pineda, Carmen; Chamizo, Verónica E; Rodríguez, Mariano; Aguilera-Tejero, Escolástico; Rivero, José-Luis L

    2016-05-01

    Although disorders of mineral metabolism and skeletal muscle are common in chronic kidney disease (CKD), their potential relationship remains unexplored. Elevations in plasma phosphate, parathyroid hormone, and fibroblastic growth factor 23 together with decreased calcitriol levels are common features of CKD. High-phosphate intake is a major contributor to progression of CKD. This study was primarily aimed to determine the influence of high-phosphate intake on muscle and to investigate whether calcitriol supplementation counteracts negative skeletal muscle changes associated with long-term uremia. Proportions and metabolic and morphological features of myosin-based muscle fiber types were assessed in the slow-twitch soleus and the fast-twitch tibialis cranialis muscles of uremic rats (5/6 nephrectomy, Nx) and compared with sham-operated (So) controls. Three groups of Nx rats received either a standard diet (0.6% phosphorus, Nx-Sd), or a high-phosphorus diet (0.9% phosphorus, Nx-Pho), or a high-phosphorus diet plus calcitriol (10 ng/kg 3 day/wk ip, Nx-Pho + Cal) for 12 wk. Two groups of So rats received either a standard diet or a high-phosphorus diet (So-Pho) over the same period. A multivariate analysis encompassing all fiber-type characteristics indicated that Nx-Pho + Cal rats displayed skeletal muscle phenotypes intermediate between Nx-Pho and So-Pho rats and that uremia-induced skeletal muscle changes were of greater magnitude in Nx-Pho than in Nx-Sd rats. In uremic rats, treatment with calcitriol preserved fiber-type composition, cross-sectional size, myonuclear domain size, oxidative capacity, and capillarity of muscle fibers. These data demonstrate that a high-phosphorus diet potentiates and low-dose calcitriol attenuates adverse skeletal muscle changes in long-term uremic rats.

  10. High-phosphorus diet maximizes and low-dose calcitriol attenuates skeletal muscle changes in long-term uremic rats.

    PubMed

    Acevedo, Luz M; López, Ignacio; Peralta-Ramírez, Alan; Pineda, Carmen; Chamizo, Verónica E; Rodríguez, Mariano; Aguilera-Tejero, Escolástico; Rivero, José-Luis L

    2016-05-01

    Although disorders of mineral metabolism and skeletal muscle are common in chronic kidney disease (CKD), their potential relationship remains unexplored. Elevations in plasma phosphate, parathyroid hormone, and fibroblastic growth factor 23 together with decreased calcitriol levels are common features of CKD. High-phosphate intake is a major contributor to progression of CKD. This study was primarily aimed to determine the influence of high-phosphate intake on muscle and to investigate whether calcitriol supplementation counteracts negative skeletal muscle changes associated with long-term uremia. Proportions and metabolic and morphological features of myosin-based muscle fiber types were assessed in the slow-twitch soleus and the fast-twitch tibialis cranialis muscles of uremic rats (5/6 nephrectomy, Nx) and compared with sham-operated (So) controls. Three groups of Nx rats received either a standard diet (0.6% phosphorus, Nx-Sd), or a high-phosphorus diet (0.9% phosphorus, Nx-Pho), or a high-phosphorus diet plus calcitriol (10 ng/kg 3 day/wk ip, Nx-Pho + Cal) for 12 wk. Two groups of So rats received either a standard diet or a high-phosphorus diet (So-Pho) over the same period. A multivariate analysis encompassing all fiber-type characteristics indicated that Nx-Pho + Cal rats displayed skeletal muscle phenotypes intermediate between Nx-Pho and So-Pho rats and that uremia-induced skeletal muscle changes were of greater magnitude in Nx-Pho than in Nx-Sd rats. In uremic rats, treatment with calcitriol preserved fiber-type composition, cross-sectional size, myonuclear domain size, oxidative capacity, and capillarity of muscle fibers. These data demonstrate that a high-phosphorus diet potentiates and low-dose calcitriol attenuates adverse skeletal muscle changes in long-term uremic rats. PMID:26869708

  11. Effects of Uremic Toxins from the Gut Microbiota on Bone: A Brief Look at Chronic Kidney Disease.

    PubMed

    Black, Ana Paula; Cardozo, Ludmila F M F; Mafra, Denise

    2015-10-01

    Patients with chronic kidney disease (CKD) frequently have mineral and bone disorders (CKD-MBD) that are caused by several mechanisms. Recent research has suggested that uremic toxins from the gut such as p-cresyl sulfate (PCS) and indoxyl sulfate (IS) could also be involved in the development of bone disease in patients with CKD. IS and PCS are produced by microbiota in the gut, carried into the plasma bound to serum albumin, and are normally excreted into the urine. However, in patients with CKD, there is an accumulation of high levels of these uremic toxins. The exact mechanisms of action of uremic toxins in bone disease remain unclear. The purpose of this brief review is to discuss the link between uremic toxins (IS and PCS) and bone mineral disease in chronic kidney disease.

  12. Protein-bound uremic toxins: new culprits of cardiovascular events in chronic kidney disease patients.

    PubMed

    Ito, Shunsuke; Yoshida, Masayuki

    2014-02-20

    Chronic kidney disease (CKD) has been considered a major risk factor for cardiovascular diseases. Although great advances have recently been made in the pathophysiology and treatment of cardiovascular diseases, CKD remains a major global health problem. Moreover, the occurrence rates of cardiovascular events among CKD patients increase even in cases in which patients undergo hemodialysis, and the mechanisms underlying the so-called "cardiorenal syndrome" are not clearly understood. Recently, small-molecule uremic toxins have been associated with cardiovascular mortality in CKD and/or dialysis patients. These toxins range from small uncharged solutes to large protein-bound structures. In this review, we focused on protein-bound uremic toxins, such as indoxyl sulfate and p-cresyl sulfate, which are poorly removed by current dialysis techniques. Several studies have demonstrated that protein-bound uremic toxins, especially indoxyl sulfate, induce vascular inflammation, endothelial dysfunction, and vascular calcification, which may explain the relatively poor prognosis of CKD and dialysis patients. The aim of this review is to provide novel insights into the effects of indoxyl sulfate and p-cresyl sulfate on the pathogenesis of atherosclerosis.

  13. Mitochondrial dysfunction in uremic cardiomyopathy

    PubMed Central

    Taylor, David; Bhandari, Sunil

    2015-01-01

    Uremic cardiomyopathy (UCM) is characterized by metabolic remodelling, compromised energetics, and loss of insulin-mediated cardioprotection, which result in unsustainable adaptations and heart failure. However, the role of mitochondria and the susceptibility of mitochondrial permeability transition pore (mPTP) formation in ischemia-reperfusion injury (IRI) in UCM are unknown. Using a rat model of chronic uremia, we investigated the oxidative capacity of mitochondria in UCM and their sensitivity to ischemia-reperfusion mimetic oxidant and calcium stressors to assess the susceptibility to mPTP formation. Uremic animals exhibited a 45% reduction in creatinine clearance (P < 0.01), and cardiac mitochondria demonstrated uncoupling with increased state 4 respiration. Following IRI, uremic mitochondria exhibited a 58% increase in state 4 respiration (P < 0.05), with an overall reduction in respiratory control ratio (P < 0.01). Cardiomyocytes from uremic animals displayed a 30% greater vulnerability to oxidant-induced cell death determined by FAD autofluorescence (P < 0.05) and reduced mitochondrial redox state on exposure to 200 μM H2O2 (P < 0.01). The susceptibility to calcium-induced permeability transition showed that maximum rates of depolarization were enhanced in uremia by 79%. These results demonstrate that mitochondrial respiration in the uremic heart is chronically uncoupled. Cardiomyocytes in UCM are characterized by a more oxidized mitochondrial network, with greater susceptibility to oxidant-induced cell death and enhanced vulnerability to calcium-induced mPTP formation. Collectively, these findings indicate that mitochondrial function is compromised in UCM with increased vulnerability to calcium and oxidant-induced stressors, which may underpin the enhanced predisposition to IRI in the uremic heart. PMID:25587120

  14. Leptin as an uremic toxin: Deleterious role of leptin in chronic kidney disease.

    PubMed

    Alix, Pascaline M; Guebre-Egziabher, Fitsum; Soulage, Christophe O

    2014-10-01

    White adipose tissue secretes a large variety of compounds named adipokines amongst which, leptin exhibits pleiotropic metabolic actions. Leptin is an anorexigenic hormone, secreted in proportion of fat mass, with additional effects on the regulation of inflammation, cardiovascular system, immunity, hematopoiesis and bone metabolism. Chronic kidney disease (CKD) is characterized by an increase of plasma leptin concentration that may be explained by a lack of renal clearance. Hyperleptinemia plays a key role in the pathogenesis of complications associated with CKD such as cachexia, protein energy wasting, chronic inflammation, insulin resistance, cardiovascular damages and bone complications. Leptin is also involved in the progression of renal disease through its pro-fibrotic and pro-hypertensive actions. Most of the adverse effects of leptin have been documented both experimentally and clinically. Leptin may therefore be considered as an uremic toxin in CKD. The aim of this review is to summarize the pathophysiological and clinical role of leptin in in vitro studies, experimental models, as well as in patients suffering from CKD.

  15. The aryl hydrocarbon receptor-activating effect of uremic toxins from tryptophan metabolism: a new concept to understand cardiovascular complications of chronic kidney disease.

    PubMed

    Sallée, Marion; Dou, Laetitia; Cerini, Claire; Poitevin, Stéphane; Brunet, Philippe; Burtey, Stéphane

    2014-03-04

    Patients with chronic kidney disease (CKD) have a higher risk of cardiovascular diseases and suffer from accelerated atherosclerosis. CKD patients are permanently exposed to uremic toxins, making them good candidates as pathogenic agents. We focus here on uremic toxins from tryptophan metabolism because of their potential involvement in cardiovascular toxicity: indolic uremic toxins (indoxyl sulfate, indole-3 acetic acid, and indoxyl-β-d-glucuronide) and uremic toxins from the kynurenine pathway (kynurenine, kynurenic acid, anthranilic acid, 3-hydroxykynurenine, 3-hydroxyanthranilic acid, and quinolinic acid). Uremic toxins derived from tryptophan are endogenous ligands of the transcription factor aryl hydrocarbon receptor (AhR). AhR, also known as the dioxin receptor, interacts with various regulatory and signaling proteins, including protein kinases and phosphatases, and Nuclear Factor-Kappa-B. AhR activation by 2,3,7,8-tetrachlorodibenzo-p-dioxin and some polychlorinated biphenyls is associated with an increase in cardiovascular disease in humans and in mice. In addition, this AhR activation mediates cardiotoxicity, vascular inflammation, and a procoagulant and prooxidant phenotype of vascular cells. Uremic toxins derived from tryptophan have prooxidant, proinflammatory, procoagulant, and pro-apoptotic effects on cells involved in the cardiovascular system, and some of them are related with cardiovascular complications in CKD. We discuss here how the cardiovascular effects of these uremic toxins could be mediated by AhR activation, in a "dioxin-like" effect.

  16. Quantitative characteristics of calcitonin-producing cells in the thyroid and lungs of uremic rats.

    PubMed

    Kasacka, Irena

    2008-01-01

    Uremia leads to a number of metabolic and hormonal disorders induced by renal failure with definite biological and clinical sequels. For this reason and the absence of reports on influence of CRF on calcitonin (CT)-producing cells of the thyroid glands and airways, the author decided to investigate the behavior of neuroendocrine cells in experimental uremia, taking CT-producing cells as an example. The aim of the present study was to examine the number and distribution of CT-producing cells in the thyroid glands and lungs of uremic rats. Fragments of the thyroids and lungs were collected one week after nephrectomy. Paraffin-embedded sections were stained with H+E and by silver impregnation. To identify neuroendocrine cells, immunohistochemical reaction was performed with the use of a specific antibody against calcitonin. It was revealed that the number of CT-immunoreactive cells decrease in the thyroid and considerable increase in the lungs of rats, when compared to the value in the control animals. The results can be regarded as the morphological manifestation of calcitonin-producing endocrine cells in the rat thyroid and lungs to disorders in the internal environment of the body induced by the impairment of renal parenchyma functioning. PMID:19141408

  17. Uremic Itch Management.

    PubMed

    Mettang, Thomas

    2016-01-01

    Uremic itch is a frequent and sometimes very tormenting symptom in patients with advanced or end-stage renal failure, with a strong negative impact on the quality of life. According to a representative study, the point prevalence of chronic itch is 25% in hemodialysis patients but may reach more than 50% in single cohorts depending on the country and dialysis efficacy. Not much is known regarding the pathogenesis of uremic itch. Besides parathyroid hormone, histamine, tryptase, and alteration of the calcium-phosphate metabolism have been suspected. More recently, derangements in the opioid system and an inflammatory condition have been investigated as suspected players in the pathogenesis of uremic itch, but remain unproven so far. Treatment of chronic itch in dialysis patients remains difficult. Besides topical application of rehydrating or immunomodulating compounds, such as γ-linolenic acid or tacrolimus treatment with nalfurafine may be helpful. Apart from that, gabapentin and pregabalin are promising drugs to alleviate uremic itch. In many cases, UVB phototherapy is effective in reducing the intensity of itch. When treating patients, one should take into account that most of the drugs available are not licensed for the treatment of itch. Therefore, a deliberate use of therapeutic options aiming for a good risk-benefit relation should be adopted. In very severe and refractory cases, patients suitable for renal transplantation might be switched to 'high urgency' status, as successful renal transplantation cures uremic pruritus in most of the cases. PMID:27578082

  18. Exploring Protein Binding of Uremic Toxins in Patients with Different Stages of Chronic Kidney Disease and during Hemodialysis.

    PubMed

    Deltombe, Olivier; Van Biesen, Wim; Glorieux, Griet; Massy, Ziad; Dhondt, Annemieke; Eloot, Sunny

    2015-10-01

    As protein binding of uremic toxins is not well understood, neither in chronic kidney disease (CKD) progression, nor during a hemodialysis (HD) session, we studied protein binding in two cross-sectional studies. Ninety-five CKD 2 to 5 patients and ten stable hemodialysis patients were included. Blood samples were taken either during the routine ambulatory visit (CKD patients) or from blood inlet and outlet line during dialysis (HD patients). Total (CT) and free concentrations were determined of p-cresylglucuronide (pCG), hippuric acid (HA), indole-3-acetic acid (IAA), indoxyl sulfate (IS) and p-cresylsulfate (pCS), and their percentage protein binding (%PB) was calculated. In CKD patients, %PB/CT resulted in a positive correlation (all p < 0.001) with renal function for all five uremic toxins. In HD patients, %PB was increased after 120 min of dialysis for HA and at the dialysis end for the stronger (IAA) and the highly-bound (IS and pCS) solutes. During one passage through the dialyzer at 120 min, %PB was increased for HA (borderline), IAA, IS and pCS. These findings explain why protein-bound solutes are difficult to remove by dialysis: a combination of the fact that (i) only the free fraction can pass the filter and (ii) the equilibrium, as it was pre-dialysis, cannot be restored during the dialysis session, as it is continuously disturbed. PMID:26426048

  19. Protein-energy wasting and uremic failure to thrive in children with chronic kidney disease: they are not small adults.

    PubMed

    Nourbakhsh, Noureddin; Rhee, Connie M; Kalantar-Zadeh, Kamyar

    2014-12-01

    Protein-energy wasting (PEW), a condition of decreased body protein and fat mass, is highly prevalent in patients with chronic kidney disease (CKD) and a potent predictor of mortality in this population. In adults with CKD, PEW has typically been defined on the basis of (1) deranged biochemical parameters, (2) reduced body mass, (3) reduced muscle mass, and (4) decreased dietary protein intake. Emerging data suggest that PEW may also commonly afflict children with CKD and have a negative impact on growth and development ("uremic failure to thrive"), yet it remains comparatively understudied and less well characterized in these patients. Given the challenges of applying adult-defined PEW criteria to the pediatric population, the authors of a recent study entitled "Protein energy wasting in children with chronic kidney disease" [Abraham et al. (2014) Pediatr Nephrol 29:1231-1238] have sought to develop a scoring system and three alterative definitions for this condition using a combination of biochemical markers, clinical measurements, and subjective reporting in children in the CKiD cohort: (1) minimal PEW definition (≥2 adult-defined PEW criteria); (2) standard PEW definition (≥3 adult-defined PEW criteria); (3) modified PEW definition (≥3 adult-defined PEW criteria, plus short stature or poor growth). These authors observed that meeting the modified PEW definition was associated with a significantly increased risk of hospitalization in unadjusted analyses, i.e., a 2.2-fold higher risk, and trended towards increased risk in multivariable adjusted analyses, i.e., 2.0-fold higher risk. At the present time, future studies validating these findings and developing further refined definitions and/or scoring systems for the detection and management of PEW in children and uremic failure to thrive are urgently needed.

  20. Psychomotor functions at various weeks of chronic renal failure in rats.

    PubMed

    Chandanathil, Merin Iype; Upadhya, Subramanya; Upadhya, Sharmila; Bhat, Gopalakrishna

    2015-04-01

    In chronic renal failure there is a gradual retention of substances in the tissues and body fluids, called as uremic retention toxins, which can bring about a number of biochemical activities in the body. Chronic renal insufficiency also leads to progressive behavioural conflict. Uremic toxins can affect both the central and the peripheral nervous system. Uremic encephalopathy is also associated with problems in cognition and memory. To study the psychomotor functional disorders in rats with progressive chronic renal failure surgical nephrectomy was done by resection method. The animals were grouped into two control groups, Sham control (SC) and normal control (NC) and two uremic groups, moderate uremia (GM) and severe uremia (GS). Psychomotor analysis was done by passive avoidance and open field in these animals at 4, 8, 12, and 16 weeks. After the incubation period, the nephrectomised groups (GM and GS) showed significant changes in exploratory, locomotor and emotional behaviour when compared to the controls (NC and SC). Psychomotor changes involve poor cognition, reduced memory, reduced locomotor activity and decreased exploratory drive and emotional disturbance like increased fear during the initial stages. During the later stages a restless behaviour was noticed, associated with diminished fear.

  1. [Study of the binding characteristics of chlorophenoxyisobutyric acid to serum proteins in chronically uremic patients : influence of dialysis and heparine (author's transl)].

    PubMed

    Lacour, B; Di Giulio, S; Nicolaï, A; Drüeke, T; Debray, M; Boulu, R G

    1982-01-01

    The binding characteristics of chlorophenoxyisobutyric acid (CPIB) to serum proteins has been studied in 10 chronically uremic patients and 9 healthy subjects using the technique of equilibrium dialysis. Scatchard analysis of the results indicated a significant decrease in association constants for low as well as for high affinity sites. The number of binding sites however was not diminished thus suggesting the presence of competitive inhibitors. Such inhibitors were dializable, at least in part, as demonstrated by in vivo-hemodialysis and in vitro-dialysis experiments. The in vivo administration of 50 mg heparin intravenously led to a striking increase in the unbound fraction of serum CPIB whereas the addition of 10 IU/ml heparin in vitro induced no change of protein binding which is in favor of only an indirect effect of heparin. In conclusion, CPIB binding to serum proteins of chronically uremic patients as compared to normal volunteers was decreased leading to an increase of its unbound circulating fraction. The observed change of protein binding appeared to be due to the presence of competitive inhibitors in uremic serum. PMID:7088259

  2. Calcific uremic arteriolopathy

    PubMed Central

    Sowers, Kurt M

    2010-01-01

    Calcific uremic arteriolopathy (CUA)/calciphylaxis is an important cause of morbidity and mortality in patients with chronic kidney disease requiring renal replacement. Once thought to be rare, it is being increasingly recognized and reported on a global scale. The uremic milieu predisposes to multiple metabolic toxicities including increased levels of reactive oxygen species and inflammation. Increased oxidative stress and inflammation promote this arteriolopathy by adversely affecting endothelial function resulting in a prothrombotic milieu and significant remodeling effects on vascular smooth muscle cells. These arteriolar pathological effects include intimal hyperplasia, inflammation, endovascular fibrosis and vascular smooth muscle cell apoptosis and differentiation into bone forming osteoblast-like cells resulting in medial calcification. Systemic factors promoting this vascular condition include elevated calcium, parathyroid hormone and hyperphosphatemia with consequent increases in the calcium × phosphate product. The uremic milieu contributes to a marked increased in upstream reactive oxygen species—oxidative stress and subsequent downstream increased inflammation, in part, via activation of the nuclear transcription factor NFκB and associated downstream cytokine pathways. Consitutive anti-calcification proteins such as Fetuin-A and matrix GLA proteins and their signaling pathways may be decreased, which further contributes to medial vascular calcification. The resulting clinical entity is painful, debilitating and contributes to the excess morbidity and mortality associated with chronic kidney disease and end stage renal disease. These same histopathologic conditions also occur in patients without uremia and therefore, the term calcific obliterative arteriolopathy could be utilized in these conditions. PMID:20716935

  3. Uremic Leontiasis Ossea in a Patient With Chronic Renal Insufficiency Demonstrated on Bone Scintigraphy.

    PubMed

    Han, Yeon-Hee; Jeong, Hwan-Jeong; Lim, Seok Tae; Sohn, Myung-Hee

    2016-08-01

    A 37-year-old woman with chronic renal insufficiency underwent bone scintigraphy to evaluate renal osteodystrophy (ROD). Markedly increased uptakes were shown in the maxilla and the mandible, which suggested extensive maxillary and mandibular hypertrophy. CT image revealed that diffuse bony thickening and ground-glass appearance in the skull, maxilla, and mandible with poor distinction of the corticomedullary junction. Whole-body bone scintigraphy images also demonstrated various skeletal characteristics of ROD. This case emphasizes the utility of bone scintigraphy for the surveillance of the whole body in ROD. PMID:27276201

  4. Restoration of bone mineralization by cinacalcet is associated with a significant reduction in calcitriol-induced vascular calcification in uremic rats.

    PubMed

    De Schutter, Tineke M; Behets, Geert J; Jung, Susanne; Neven, Ellen; D'Haese, Patrick C; Querfeld, Uwe

    2012-11-01

    The present study investigated to what extent normalization of bone turnover goes along with a reduction of high-dose calcitriol-induced vascular calcifications in uremic rats. Five groups of male Sprague-Dawley rats were studied: sham-operated controls (n = 7), subtotally nephrectomized (SNX) uremic (CRF) animals (n = 12), CRF + calcitriol (vitD) (0.25 μg/kg/day) (n = 12), CRF + vitD + cinacalcet (CIN) (10 mg/kg/day) (n = 12), and CRF + vitD + parathyroidectomy (PTX) (n = 12). Treatment started 2 weeks after SNX and continued for the next 14 weeks. High-dose calcitriol treatment in hyperparathyroid rats went along with the development of distinct vascular calcification, which was significantly reduced by >50 %, in both CIN-treated and PTX animals. Compared to control animals and those of the CRF group, calcitriol treatment either in combination with CIN or PTX or not was associated with a significant increase in bone area comprising ±50 % of the total tissue area. However, whereas excessive woven bone accompanied by a dramatically increased osteoid width/area was seen in the CRF + vitD group, CIN treatment and PTX resulted in significantly reduced serum PTH level, which was accompanied by a distinct reduction of both the bone formation rate and the amount of osteoid. These data indicate that less efficient calcium and phosphorus incorporation in bone inherent to the severe hyperparathyroidism in vitamin D-treated uremic rats goes along with excessive vascular calcification, a process which is partially reversed by CIN treatment in combination with a more efficacious bone mineralization, thus restricting the availability of calcium and phosphate for being deposited in the vessel wall.

  5. A novel UPLC-MS-MS method for simultaneous determination of seven uremic retention toxins with cardiovascular relevance in chronic kidney disease patients.

    PubMed

    Boelaert, Jente; Lynen, Frédéric; Glorieux, Griet; Eloot, Sunny; Van Landschoot, Maria; Waterloos, Marie-Anne; Sandra, Pat; Vanholder, Raymond

    2013-02-01

    Chronic kidney disease (CKD) is a devastating illness characterized by accumulation of uremic retention solutes in the body. The objective of this study was to develop and validate a simple, rapid, and robust UPLC-MS-MS method for simultaneous determination, in serum, of seven organic acid uremic retention toxins, namely uric acid (UA), hippuric acid (HA), indoxylsulfate (IS), p-cresylglucuronide (pCG), p-cresylsulfate (pCS), indole-3-acetic acid (IAA), and 3-carboxy-4-methyl-5-propyl-2-furanpropionic acid (CMPF). Isotopically labeled internal standards (d(5)-HA; 1,3-(15)N(2)-UA, and d(5)-IAA) were used to correct for variations in sample preparation and system performance. Separation on a C18 column was followed by negative electrospray ionization and tandem mass spectrometric detection. Accuracy was below the 15 % threshold. Within-day precision varied from 0.60 to 4.54 % and between-day precision was below 13.33 % for all compounds. The applicability of the method was evaluated by analyzing 78 serum samples originating both from healthy controls and from patients at different stages of CKD. These results were compared with those obtained by use of conventional HPLC-PDA-FLD methods. A good correlation was obtained between both methods for all compounds. PMID:23307120

  6. Humoral inhibitors of the immune response in uremia. V. Induction of suppressor cells in vitro by uremic serum.

    PubMed Central

    Raskova, J.; Raska, K.

    1983-01-01

    The mechanism of inhibition of mixed lymphocyte reaction (MLR) by serum of chronically uremic rats has been studied. The inhibitory activity of the serum has been associated with a discrete subset of very low density lipoproteins (VLDL) of Sf 100-400. The degree of the inhibitory activity of uremic serum correlates with the severity of uremia. Spleen cells from normal rats incubated for 20 hours with uremic serum or its VLDL fraction suppress the response of control syngeneic cells in the MLR. Induction of such suppressor activity does not require cell proliferation because it is not inhibited by mitomycin C. although the exact identity of the induced suppressor cells has not been established, they may be macrophages. The suppressor activity of induced spleen cells can be markedly reduced by filtration of spleen cells on glass wool or on nylon wool columns. Reconstruction experiments show that the adherent cell fraction of spleen cells exposed to uremic serum suppresses the response of the nonadherent fraction of control spleen cells. These results indicate that the immunosuppressive effects of rat uremic serum in vitro involve the induction of suppressor cells. PMID:6221666

  7. Colon-derived uremic biomarkers induced by the acute toxicity of Kansui radix: A metabolomics study of rat plasma and intestinal contents by UPLC-QTOF-MS(E).

    PubMed

    Yang, Zhou; Hou, Jin-Jun; Qi, Peng; Yang, Min; Yan, Bing-Peng; Bi, Qi-Rui; Feng, Rui-Hong; Yang, Wen-Zhi; Wu, Wan-Ying; Guo, De-An

    2016-07-15

    Kansui radix (KR) is a poisonous Chinese herbal medicine recorded in the Chinese Pharmacopoeia, and the acute toxicity obstructs its clinical applications. To explore its acute toxicity mechanism to enhance clinical safety, a metabolomics study based on UPLC-ESI-QTOF-MS(E) was performed. Wistar rats were exposed for 4h to the aqueous and ethyl acetate extracts prepared from KR at a high dose (25g/kg). The contents of six different sections of rat intestine, including the duodenum, jejunum, ileum, cecum, colon, and rectum were collected as samples for the first time, as well as the rat plasma. The interesting results showed that only those rats exposed to the ethyl acetate extract showed a watery diarrhea, similar to the observed acute human toxicity. The identified biomarkers found in the plasma, such as phenol sulfate, indoxyl sulfate, and p-cresol sulfate were significantly perturbed in the rats. These biomarkers are known as colon-derived uremic compounds, which were first reported with respect to KR. The three essential amino acids which produced these biomarkers were only found in the contents of colon and rectum. A hypothesis was proposed that only the colon-derived uremic compounds induced by KR might be responsible for the acute toxicity. Three traditional process methods to reduce the toxicity of KR were compared based on these biomarkers, and different levels of toxicity modulation were observed. These results may be helpful to further understand the mechanism of acute toxicity, and the relevance of the traditional process methods to ameliorate the adverse effects of KR.

  8. Effects of Uremic Toxins on Transport and Metabolism of Different Biopharmaceutics Drug Disposition Classification System (BDDCS) Xenobiotics

    PubMed Central

    Reyes, Maribel; Benet, Leslie Z.

    2013-01-01

    Chronic kidney disease (CKD) is recognized to cause pharmacokinetic changes in renally excreted drugs; however, pharmacokinetic changes are also reported for drugs that are non-renally eliminated. Few studies have investigated how uremic toxins may affect drug transporters and metabolizing enzymes and how these may result in pharmacokinetic/metabolic changes in CKD. Here, we investigated the effects of uremic toxins and human uremic serum on the transport of the prototypical transporter substrate [3H]-estrone sulfate and three BDDCS drugs, propranolol, losartan, and eprosartan. We observed a significant decrease in [3H]-estrone sulfate, losartan, and eprosartan uptake with some uremic toxins in both transfected cells and rat hepatocytes. The uptake of losartan was decreased in rat and human hepatocytes (28%, and 48% respectively) in the presence of hemodialysis (HD) serum. Time-course studies of losartan showed a 27%, 65% and 68% increase in AUC in the presence of HD serum, rifampin, and sulfaphenazole respectively. Intracellular losartan AUC decreased significantly in the treatment groups and the metabolite AUC decreased by 41% and 26% in rifampin and sulfaphenazole treated group. The intracellular AUC of eprosartan increased 190% in the presence of HD serum. These studies indicate that the uremic toxins contained in HD serum play an important role in drug disposition through drug transporters, and that there would be differential effects depending on the BDDCS classification of the drug. PMID:21618544

  9. Distribution of purine nucleotides in uremic fluids and tissues.

    PubMed

    Rutkowski, Bolesław; Rutkowski, Przemysław; Słomińska, Ewa; Swierczyński, Julian

    2010-09-01

    There are almost 100 different substances called uremic toxins. In this study, we analyze all findings concerning the new family of uremic compounds--nicotinamide end products: N-methyl-2-pyridone-5-carboxamide (Met2PY), N-methyl-4-pyridone-5-carboxamide, newly described 4-pyridone-3-carboxamide-1-beta-D-ribonucleoside (4PYR) and 4-pyridone-3-carboxamide-1-beta-D-ribonucleoside triphosphate (4PYTP). After few years of studies, we have found that these substances have higher plasma concentration in patients with chronic renal failure (CRF) in comparison with the healthy population. We noted a 40-fold increase in plasma 4PYR concentration in patients with CRF. This increment correlates significantly with the decline of kidney function measured as an increase of serum creatinine concentration and decrease of estimated glomerular filtration rate. Tested compounds are present and measurable in physiological fluids and tissues. We found higher saliva Met2PY concentration in patients with CRF in comparison with controls. Saliva Met2PY correlated negatively with estimated glomerular filtration rate and positively with serum creatinine concentration. One-third of studied group had higher concentration of Met2PY in the saliva than in plasma, and this segment of patients may be called as "good excretors." In rats with experimental CRF, we found that both Met2PY and N-methyl-4-pyridone-5-carboxamide accumulated in selected tissues. We also demonstrated formation of 4PYTP in intact human erythrocytes during incubation with the precursor 4PYR. Incubation with 4PYR leads to lowering concentration of adenosine-5'-triphosphate. 4PYTP formation may be a way to remove 4PYR from the circulation and save adenosine-5'-triphosphate depletion. Summarizing, end products of the nicotinamide family are members of uremic toxins; however, exact pathophysiological role of these compounds in the development of uremic syndrome needs further studies. PMID:20797575

  10. Mechanisms of acute uremic encephalopathy: early activation of Fos and Fra-2 gene products in different nuclei/areas of the rat brain.

    PubMed

    Heidland, August; Sebekova, Katarina; Klassen, André; Palkovits, Miklós

    2010-09-01

    High levels of various uremic toxins such as guanidino compounds and advanced glycation endproducts, as well as an excess of parathyroid hormones, are involved in the pathogenesis of acute uremic encephalopathy. Moreover, distant effects of the damaged kidney with enhanced production of inflammatory mediators are implicated. Data on the pump activity of an abnormal Na-K-ATPase and inhibition of the organic anion transporter system in the brain have been published previously. Recently, the effect of an experimentally induced acute renal failure (ARF) on the neuronal cell activation of Fos and Fra-2 in the rat brain was investigated by immunohistochemistry. ARF was induced by using the following 3 rat models: bilateral nephrectomy, bilateral ureter ligation, and uranyl acetate injection with corresponding controls. The Fos and the Fra-2 immunoreactive neurons of the brain were determined in a total of 120 brain areas over a period of 3 days post bilateral nephrectomy and bilateral ureter ligation and 12 days after uranyl acetate. An activation response was observed in 73 of 120 areas of the brain. The responses were classified into 4 groups: (1) biogenic amines (noradrenaline, adrenaline, histamine, and 5-hydroxytryptamine), (2) stress-sensitive forebrain areas, (3) neuronal cell groups involved in the regulation of water and electrolyte homeostasis, and (4) central autonomic cell groups. In the uranyl acetate-induced ARF, activation of Fos and Fra-2 immunoreactivity took place at the earliest time-point (3 hours) which persisted even after improvement of ARF. This suggests the involvement of the toxic effects of uranium as a result of its accumulation in the brain.

  11. Effects of acute and chronic uremia on active cation transport in rat myocardium

    SciTech Connect

    Druml, W.; Kelly, R.A.; England, B.K.; O'Hara, D.S.; Mitch, W.E. )

    1990-12-01

    As abnormalities of active cation transport could contribute to the genesis of uremic cardiomyopathy, we investigated myocardial sodium pump function in rats with acute renal failure (ARF) and with a model of experimental chronic renal failure (CRF) that has metabolic similarities to advanced chronic uremia in humans. CRF rats were hypertensive and had left ventricular hypertrophy (33% higher heart:body weight ratio; P less than 0.01) at four weeks compared to pair-fed sham-operated rats. Importantly, both ouabain- and furosemide-sensitive 86Rb uptake rates were unchanged in left ventricular myocardial slices from CRF, and the intracellular sodium concentration was not different from that of control rats even though skeletal muscle sodium was increased, as we found previously. Insulin-stimulated, ouabain-sensitive 86Rb influx was also preserved. There also were no abnormalities in myocardium cation transport in rats with ARF. However, (3H)ouabain binding was decreased 45% in CRF rats (P less than 0.01); it was unchanged in acute uremia. Decreased ouabain binding in chronic uremia was due entirely to fewer low affinity (3H)ouabain binding sites (the binding affinity for ouabain was unaffected). We conclude that in chronic, (but not acute) renal failure, sodium pump number is reduced in myocardium but intracellular sodium is unchanged and active cation flux rates are maintained. These results emphasize that in rats with chronic uremia, intracellular sodium homeostasis is preserved in myocardium, despite the presence of marked abnormalities of active cation transport in skeletal muscle that are characteristic of chronic uremia.

  12. Emerging biomarkers for evaluating cardiovascular risk in the chronic kidney disease patient: how do new pieces fit into the uremic puzzle?

    PubMed

    Stenvinkel, Peter; Carrero, Juan Jesús; Axelsson, Jonas; Lindholm, Bengt; Heimbürger, Olof; Massy, Ziad

    2008-03-01

    Premature cardiovascular disease (CVD), including stroke, peripheral vascular disease, sudden death, coronary artery disease, and congestive heart failure, is a notorious problem in patients with chronic kidney disease (CKD). Because the presence of CVD is independently associated with kidney function decline, it appears that the relationship between CKD and CVD is reciprocal or bidirectional, and that it is this association that leads to the vicious circle contributing to premature death. As randomized, placebo-controlled trials have so far been disappointing and unable to show a survival benefit of various treatment strategies, such a lipid-lowering, increased dialysis dose and normalization of hemoglobin, the risk factor profile seems to be different in CKD compared with the general population. Indeed, seemingly paradoxical associations between traditional risk factors and cardiovascular outcome in patients with advanced CKD have complicated our efforts to identify the real cardiovascular culprits. This review focuses on the many new pieces that need to be fit into the complicated puzzle of uremic vascular disease, including persistent inflammation, endothelial dysfunction, oxidative stress, and vascular ossification. Each of these is not only highly prevalent in CKD but also more strongly linked to CVD in these patients than in the general population. However, a causal relationship between these new markers and CVD in CKD patients remains to be established. Finally, two novel disciplines, proteomics and epigenetics, will be discussed, because these tools may be helpful in the understanding of the discussed vascular risk factors.

  13. Rat growth during chronic centrifugation

    NASA Technical Reports Server (NTRS)

    Pitts, G. C.; Oyama, J.

    1978-01-01

    Female weanling rats were chronically centrifuged at 4.15 G with controls at terrestrial gravity. Samples were sacrificed for body composition studies at 0, 28, 63, 105 and 308 days of centrifugation. The centrifuged group approached a significantly lower mature body mass than the controls (251 and 318g) but the rate of approach was the same in both groups. Retirement to 1G on the 60th day resulted in complete recovery. Among individual components muscle, bone, skin, CNS, heart, kidneys, body water and body fat were changed in the centrifuged group. However, an analysis of the growth of individual components relative to growth of the total fat-free compartment revealed that only skin (which increased in mass) was responding to centrifugation per se.

  14. Future Avenues to Decrease Uremic Toxin Concentration.

    PubMed

    Vanholder, Raymond C; Eloot, Sunny; Glorieux, Griet L R L

    2016-04-01

    In this article, we review approaches for decreasing uremic solute concentrations in chronic kidney disease and in particular, in end-stage renal disease (ESRD). The rationale to do so is the straightforward relation between concentration and biological (toxic) effect for most toxins. The first section is devoted to extracorporeal strategies (kidney replacement therapy). In the context of high-flux hemodialysis and hemodiafiltration, we discuss increasing dialyzer blood and dialysate flows, frequent and/or extended dialysis, adsorption, bioartificial kidney, and changing physical conditions within the dialyzer (especially for protein-bound toxins). The next section focuses on the intestinal generation of uremic toxins, which in return is stimulated by uremic conditions. Therapeutic options are probiotics, prebiotics, synbiotics, and intestinal sorbents. Current data are conflicting, and these issues need further study before useful therapeutic concepts are developed. The following section is devoted to preservation of (residual) kidney function. Although many therapeutic options may overlap with therapies provided before ESRD, we focus on specific aspects of ESRD treatment, such as the risks of too-strict blood pressure and glycemic regulation and hemodynamic changes during dialysis. Finally, some recommendations are given on how research might be organized with regard to uremic toxins and their effects, removal, and impact on outcomes of uremic patients. PMID:26500179

  15. Exploiting the Nephrotoxic Effects of Venom from the Sea Anemone, Phyllodiscus semoni, to Create a Hemolytic Uremic Syndrome Model in the Rat

    PubMed Central

    Mizuno, Masashi; Ito, Yasuhiko; Morgan, B. Paul

    2012-01-01

    In the natural world, there are many creatures with venoms that have interesting and varied activities. Although the sea anemone, a member of the phylum Coelenterata, has venom that it uses to capture and immobilise small fishes and shrimp and for protection from predators, most sea anemones are harmless to man. However, a few species are highly toxic; some have venoms containing neurotoxins, recently suggested as potential immune-modulators for therapeutic application in immune diseases. Phyllodiscus semoni is a highly toxic sea anemone; the venom has multiple effects, including lethality, hemolysis and renal injuries. We previously reported that venom extracted from Phyllodiscus semoni induced acute glomerular endothelial injuries in rats resembling hemolytic uremic syndrome (HUS), accompanied with complement dysregulation in glomeruli and suggested that the model might be useful for analyses of pathology and development of therapeutic approaches in HUS. In this mini-review, we describe in detail the venom-induced acute renal injuries in rat and summarize how the venom of Phyllodiscus semoni could have potential as a tool for analyses of complement activation and therapeutic interventions in HUS. PMID:22851928

  16. Effects of Sucroferric Oxyhydroxide Compared to Lanthanum Carbonate and Sevelamer Carbonate on Phosphate Homeostasis and Vascular Calcifications in a Rat Model of Chronic Kidney Failure

    PubMed Central

    Phan, Olivier; Maillard, Marc; Malluche, Hartmut H.; Stehle, Jean-Christophe; Funk, Felix; Burnier, Michel

    2015-01-01

    Elevated serum phosphorus, calcium, and fibroblast growth factor 23 (FGF23) levels are associated with cardiovascular disease in chronic renal disease. This study evaluated the effects of sucroferric oxyhydroxide (PA21), a new iron-based phosphate binder, versus lanthanum carbonate (La) and sevelamer carbonate (Se), on serum FGF23, phosphorus, calcium, and intact parathyroid hormone (iPTH) concentrations, and the development of vascular calcification in adenine-induced chronic renal failure (CRF) rats. After induction of CRF, renal function was significantly impaired in all groups: uremic rats developed severe hyperphosphatemia, and serum iPTH increased significantly. All uremic rats (except controls) then received phosphate binders for 4 weeks. Hyperphosphatemia and increased serum iPTH were controlled to a similar extent in all phosphate binder-treatment groups. Only sucroferric oxyhydroxide was associated with significantly decreased FGF23. Vascular calcifications of the thoracic aorta were decreased by all three phosphate binders. Calcifications were better prevented at the superior part of the thoracic and abdominal aorta in the PA21 treated rats. In adenine-induced CRF rats, sucroferric oxyhydroxide was as effective as La and Se in controlling hyperphosphatemia, secondary hyperparathyroidism, and vascular calcifications. The role of FGF23 in calcification remains to be confirmed. PMID:26221597

  17. Effects of Sucroferric Oxyhydroxide Compared to Lanthanum Carbonate and Sevelamer Carbonate on Phosphate Homeostasis and Vascular Calcifications in a Rat Model of Chronic Kidney Failure.

    PubMed

    Phan, Olivier; Maillard, Marc; Malluche, Hartmut H; Stehle, Jean-Christophe; Funk, Felix; Burnier, Michel

    2015-01-01

    Elevated serum phosphorus, calcium, and fibroblast growth factor 23 (FGF23) levels are associated with cardiovascular disease in chronic renal disease. This study evaluated the effects of sucroferric oxyhydroxide (PA21), a new iron-based phosphate binder, versus lanthanum carbonate (La) and sevelamer carbonate (Se), on serum FGF23, phosphorus, calcium, and intact parathyroid hormone (iPTH) concentrations, and the development of vascular calcification in adenine-induced chronic renal failure (CRF) rats. After induction of CRF, renal function was significantly impaired in all groups: uremic rats developed severe hyperphosphatemia, and serum iPTH increased significantly. All uremic rats (except controls) then received phosphate binders for 4 weeks. Hyperphosphatemia and increased serum iPTH were controlled to a similar extent in all phosphate binder-treatment groups. Only sucroferric oxyhydroxide was associated with significantly decreased FGF23. Vascular calcifications of the thoracic aorta were decreased by all three phosphate binders. Calcifications were better prevented at the superior part of the thoracic and abdominal aorta in the PA21 treated rats. In adenine-induced CRF rats, sucroferric oxyhydroxide was as effective as La and Se in controlling hyperphosphatemia, secondary hyperparathyroidism, and vascular calcifications. The role of FGF23 in calcification remains to be confirmed.

  18. Uremic leontiasis ossea.

    PubMed

    Haroyan, Harut; Bos, Aron; Ginat, Daniel Thomas

    2015-01-01

    Uremic leontiasis ossea is a rare manifestation of renal osteodystrophy clinically characterized by jaw enlargement, widening of the nares, flattening of the nasal bridge, and increased interdental spacing. Computed tomography (CT) findings are particular characteristic and include serpiginous tunneling within the maxillofacial bones and cortical bone resorption. Nuclear medicine scans are also useful for demonstrating hyperplasia of the parathyroid glands. Ultimately, the diagnosis of uremic leontiasis ossea can be made non-invasively through a combination of clinical parameters and imaging findings, as described in this article. PMID:25224511

  19. Effect of Different Stages of Chronic Kidney Disease and Renal Replacement Therapies on Oxidant-Antioxidant Balance in Uremic Patients

    PubMed Central

    Tbahriti, Hadja Fatima; Kaddous, Abbou; Bouchenak, Malika; Mekki, Khedidja

    2013-01-01

    Oxidative stress seems to be involved in the path physiology of cardiovascular complications of chronic kidney disease (CKD). In this study, we determined the effect of different stages of CKD and substitutive therapies on oxidative stress. One hundred sixty-seven patients (age: 44 ± 06 years; male/female: 76/91) with CKD were divided into 6 groups according to the National Kidney Foundation classification. Prooxidant status was assessed by assaying thiobarbituric acid reactive substances, hydroperoxides, and protein carbonyls. Antioxidant defence was performed by analysis of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, vitamin E, Iron, and bilirubin. TBARS and LPO were higher in HD patients compared to other groups (P < 0.001), while protein carbonyls were more increased in PD patients. The antioxidant enzymes were declined already at severe stage of CKD and they were declined notably in HD patients (P < 0.001). Similar observation was found for vitamin E, Fe, and bilirubin where we observed a significant decrease in the majority of study groups, especially in HD patients (P < 0.001). The evolution of CKD was associated with elevated OS. HD accentuates lipid, while PD aggravates protein oxidation. However, the activity of antioxidant enzymes was altered by impaired renal function and by both dialysis treatments. PMID:24416590

  20. Thrombosis in the uremic milieu--emerging role of "thrombolome".

    PubMed

    Shashar, Moshe; Francis, Jean; Chitalia, Vipul

    2015-01-01

    Chronic kidney disease (CKD) is characterized by retention of a number of toxins, which unleash cellular damage. CKD environment with these toxins and a host of metabolic abnormalities (collectively termed as uremic milieu) is highly thrombogenic. CKD represents a strong and independent risk factor for both spontaneous venous and arterial (postvascular injury) thrombosis. Emerging evidence points to a previously unrecognized role of some of the prothrombotic uremic toxins. Here, we provide an overview of thrombosis in CKD and an update on indolic uremic toxins, which robustly increase tissue factor, a potent procoagulant, in several vascular cell types enhancing thrombosis. This panel of uremic toxins, which we term "thrombolome" (thrombosis and metabolome), represents a novel risk factor for thrombosis and can be further explored as biomarker for postvascular interventional thrombosis in patients with CKD.

  1. Uremic frost: a harbinger of impending renal failure.

    PubMed

    Saardi, Karl M; Schwartz, Robert A

    2016-01-01

    Uremic frost is a striking cutaneous finding seen in patients with severe kidney disease. Familiarity with this condition can be a life-saving signal to initiate urgent dialysis. Uremic frost generally occurs at blood urea nitrogen levels of approximately 200 mg/dl, although it may arise with less severe uremia. Recently confirmed urea transporters in the skin may play a role in the development of uremic frost. Alternatively, damage to the cutaneous microvasculature and pilosebaceous units, as seen in chronic kidney disease, could account for the high levels of urea deposited outside the skin. The treatment of uremic frost is largely aimed at correcting the underlying cause of uremia and the other life-threatening conditions associated with renal failure.

  2. The role of oxygen free radicals in the development of chronic renal failure

    SciTech Connect

    Trachtman, H.; Wilson, D.; Rao, P.S. )

    1992-01-01

    This study examined whether there is increased production of oxygen free radicals during chronic renal failure. Rats subjected to 3/4 nephrectomy and sham operated controls were killed after 3 weeks. Lipid extracts of plasma and renal tissue were examined by HPLC and kidney specimens were also analyzed by EPR spectroscopy. The redox capacity of blood was assessed using nitroblue tetrazolium and plasma ascorbate levels were measured with HPLC. There was no detectable renal production of oxygen free radicals in rats with chronic renal failure. Kidney parenchymal content of other oxidants and the oxidant: reductant ratio were similar in control and uremic animals. The plasma redox capacity and ascorbate levels were elevated in uremic rats. The authors conclude that early in the course of chronic renal failure, there is not excessive production of oxygen free radicals. There is accumulation of reductants, primarily ascorbate, in the plasma of uremic animals.

  3. Hemolytic uremic syndrome

    PubMed Central

    Canpolat, Nur

    2015-01-01

    Hemolytic uremic syndrome (HUS) is a clinical syndrome characterized by the triad of thrombotic microangiopathy, thrombocytopenia, and acute kidney injury. Hemolytic uremic syndrome represents a heterogeneous group of disorders with variable etiologies that result in differences in presentation, management and outcome. In recent years, better understanding of the HUS, especially those due to genetic mutations in the alternative complement pathway have provided an update on the terminology, classification, and treatment of the disease. This review will provide the updated classification of the disease and the current diagnostic and therapeutic approaches on the complement-mediated HUS in addition to STEC-HUS which is the most common cause of the HUS in childhood. PMID:26265890

  4. Does the uremic milieu affect the epigenotype?

    PubMed

    Stenvinkel, Peter; Ekström, Tomas J

    2009-01-01

    Epigenetics is a discipline that for many years has languished in the shadow of its genomic big brother. Because our understanding of the role played by epigenetics in chronic kidney disease remains in its infancy, further studies are needed to understand the associations, for instance, of aberrant DNA methylation in relation to uremic dysmetabolism, and its presumably very complex interactions in the development of premature uremic vascular disease. Further research is also needed to study the association between aberrant global DNA-methylation, gene-level methylation status, and the silencing (or activation) of candidate genes associated with atherosclerosis. Insofar as it seems possible to manipulate the epigenome, the effects of various epigenetic-targeted and pathway-targeted therapeutic approaches on unbalanced DNA methylation, gene silencing, and vascular health and outcomes should be explored further in uremia.

  5. The effect of activated charcoal on adenine-induced chronic renal failure in rats.

    PubMed

    Ali, Badreldin H; Alza'abi, Mohamed; Ramkumar, Aishwarya; Al-Lawati, Intisar; Waly, Mostafa I; Beegam, Sumaya; Nemmar, Abderrahim; Brand, Susanne; Schupp, Nicole

    2014-03-01

    Activated charcoal (AC) is a sorbent that has been shown to remove urinary toxins like urea and indoxyl sulfate. Here, the influence of AC on kidney function of rats with experimental chronic renal failure (CRF) is investigated. CRF was induced in rats by feeding adenine (0.75%) for four weeks. As an intervention, AC was added to the feed at concentrations of 10%, 15% or 20%. Adenine treatment impaired kidney function: it lowered creatinine clearance and increased plasma concentrations of creatinine, urea, neutrophil gelatinase-associated lipocalin and vanin-1. Furthermore, it raised plasma concentrations of the uremic toxins indoxyl sulfate, phosphate and uric acid. Renal morphology was severely damaged and histopathological markers of inflammation and fibrosis were especially increased. In renal homogenates, antioxidant indices, including superoxide dismutase and catalase activity, total antioxidant capacity and reduced glutathione were adversely affected. Most of these changes were significantly ameliorated by dietary administration of AC at a concentration of 20%, while effects induced by lower doses of dietary AC on adenine nephrotoxicity were not statistically significant. The results suggest that charcoal is a useful sorbent agent in dietary adenine-induced CRF in rats and that its usability as a nephroprotective agent in human kidney disease should be studied.

  6. Ameliorative Effect of Chrysin on Adenine-Induced Chronic Kidney Disease in Rats

    PubMed Central

    Ali, Badreldin H.; Adham, Sirin A.; Al Za’abi, Mohammed; Waly, Mostafa I.; Yasin, Javed; Nemmar, Abderrahim; Schupp, Nicole

    2015-01-01

    Chrysin (5, 7- dihydroxyflavone) is a flavonoid with several pharmacological properties that include antioxidant, anti-inflammatory and antiapoptotic activities. in this work, we investigated some effects of three graded oral doses of chrysin (10, 50 and 250 mg/kg) on kidney structure and function in rats with experimental chronic renal disease (CKD) induced by adenine (0.25% w/w in feed for 35 days), which is known to involve inflammation and oxidative stress. Using several indices in plasma, urine and kidney homogenates, adenine was found to impair kidney function as it lowered creatinine clearance and increased plasma concentrations of creatinine, urea, neutrophil gelatinase-associated lipocalin and N-Acetyl-beta-D-glucosaminidase activity. Furthermore, it raised plasma concentrations of the uremic toxin indoxyl sulfate, some inflammatory cytokines and urinary albumin concentration. Renal morphology was severely damaged and histopathological markers of inflammation and fibrosis were especially increased. In renal homogenates, antioxidant indices, including superoxide dismutase and catalase activities, total antioxidant capacity and reduced glutathione were all adversely affected. Most of these adenine – induced actions were moderately and dose -dependently mitigated by chrysin, especially at the highest dose. Chrysin did not cause any overt adverse effect on the treated rats. The results suggest that different doses of chrysin produce variable salutary effects against adenine-induced CKD in rats, and that, pending further pharmacological and toxicological studies, its usability as a possible ameliorative agent in human CKD should be considered. PMID:25909514

  7. Cardiovascular parameters in rat model of chronic renal failure induced by subtotal nephrectomy.

    PubMed

    Svíglerová, J; Kuncová, J; Nalos, L; Tonar, Z; Rajdl, D; Stengl, M

    2010-01-01

    Chronic renal failure (CRF) is associated with high incidence of cardiovascular complications. To clarify pathogenesis of CRF numerous animal models have been developed. The aim of our work was to describe methodology of subtotal surgical renal ablation in rat and to characterize some biochemical and cardiovascular parameters of this animal model. Male rats underwent 5/6 surgical nephrectomy or sham operations in two steps. The following parameters were measured on day 10 and in week 10 after the surgery: plasma concentrations of creatinine and urea, blood pressure, resting heart rate, chronotropic response to atropine and metipranol, heart ventricles weight, contraction parameters and action potential duration in the left ventricle. Increased serum concentrations of creatinine and urea, decreased creatinine clearance, polyuria and alteration of the remnant kidney tissue were found in CRF rats. Changes in cardiovascular parameters identified after subtotal nephrectomy resembled alterations of cardiovascular system in uremic patients and included hypertension, elevated resting heart rate, diminished parasympathetic cardiac tone, hypertrophy of the left ventricle associated with weakened force of contraction, prolonged contraction and relaxation and shortening of action potential duration. These data suggest that the present model can be a useful tool in the study of CRF and its cardiovascular complications.

  8. Altered material properties are responsible for bone fragility in rats with chronic kidney injury.

    PubMed

    Iwasaki, Yoshiko; Kazama, Junichiro J; Yamato, Hideyuki; Matsugaki, Aira; Nakano, Takayoshi; Fukagawa, Masafumi

    2015-12-01

    Chronic kidney disease (CKD) is associated with an increased risk of fragility fractures, but the underlying pathophysiological mechanism remains obscure. We performed an in vivo experimental study to examine the roles of uremia and abnormal mineral/parathyroid metabolism in the development of bone metabolic abnormalities in uremic rats. Male Sprague-Dawley rats were divided into four groups, comprising sham operation (high turnover bone control=HTB-Cont), 5/6-nephrectomy (high turnover bone nephrectomized=HTB-Nx), thyroparathyroidectomy (low turnover bone control=LTB-Cont), and thyroparathyroidectomy plus 5/6 nephrectomy (low turnover bone nephrectomized=LTB-Nx), and maintained for 16 weeks. Uremia was successfully created in the LTB-Nx and HTB-Nx groups, while hyperparathyroidism was only found in the HTB-Nx group. Cancellous bone histomorphometry revealed significantly higher bone turnover in the HTB-Nx group than in the LTB-Nx group. Storage modulus at 1 Hz and tan delta in cortical bone of the femur, which represent the viscoelastic mechanical properties, were significantly lower in both Nx groups than in the Cont groups regardless of bone metabolism. Pentosidine-to-matrix ratio was increased and crystallinity was decreased in both Nx groups regardless of bone turnover. Mineral-to-matrix ratio was significantly decreased in the HTB-Nx group, but increased in the LTB-Nx group. Enzymatic collagen crosslinks were decreased in the HTB-Nx group. The degree of orientation of the c-axis in carbonated hydroxyapatite (biological apatite=BAp) crystallites was decreased in both Nx groups regardless of bone metabolism. Stepwise multivariate regression revealed that pentosodine-to-matrix ratio and BAp preferential c-axis orientation were significantly associated with storage modulus and tan delta. In conclusion, bone elastic mechanical properties deteriorated regardless of bone metabolism or bone mass in rats with chronic kidney injury. Various changes in bone mineral

  9. Atypical Hemolytic Uremic Syndrome

    PubMed Central

    Kavanagh, David; Goodship, Tim H.; Richards, Anna

    2013-01-01

    Summary Hemolytic uremic syndrome (HUS) is a triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute renal failure. The atypical form of HUS is a disease characterized by complement overactivation. Inherited defects in complement genes and acquired autoantibodies against complement regulatory proteins have been described. Incomplete penetrance of mutations in all predisposing genes is reported, suggesting that a precipitating event or trigger is required to unmask the complement regulatory deficiency. The underlying genetic defect predicts the prognosis both in native kidneys and after renal transplantation. The successful trials of the complement inhibitor eculizumab in the treatment of atypical HUS will revolutionize disease management. PMID:24161037

  10. Effects of chronic renal failure on kidney drug transporters and cytochrome P450 in rats.

    PubMed

    Naud, Judith; Michaud, Josée; Beauchemin, Stéphanie; Hébert, Marie-Josée; Roger, Michel; Lefrancois, Stéphane; Leblond, Francois A; Pichette, Vincent

    2011-08-01

    Chronic renal failure (CRF) leads to decreased drug renal clearance due to a reduction in the glomerular filtration rate. However, little is known about how renal failure affects renal metabolism and elimination of drugs. Because both depend on the activity of uptake and efflux by renal transporters as well as enzymes in tubular cells, the purpose of this study was to investigate the effects of CRF on the expression and activity of select renal drug transporters and cytochrome P450. Two groups of rats were studied: control and CRF (induced by 5/6 nephrectomy). Compared with control rats, we observed reductions in the expression of both protein and mRNA of Cyp1a, sodium-dependent phosphate transport protein 1, organic anion transporter (Oat)1, 2, and 3, OatK1/K2, organic anion-transporting polypeptide (Oatp)1 and 4c1, P-glycoprotein, and urate transporter 1, whereas an induction in the protein and mRNA expression of Mrp2, 3, and 4 and Oatp2 and 3 was observed. Cyp3a expression remained unchanged. Similar results were obtained by incubating a human proximal tubule cell line (human kidney-2) with sera from CRF rats, suggesting the presence of uremic modulators. Finally, the renal elimination of [(3)H]digoxin and [(14)C]benzylpenicillin was decreased in CRF rats, compared with controls, as shown by a 4- and 9-fold accumulation, respectively, of these drugs in kidneys of rats in CRF. Our results demonstrate that CRF affects the expression and activity of several kidney drug transporters leading to the intrarenal accumulation of drugs and reduced renal clearance that could, at least partially, explain the tubular toxicity of many drugs.

  11. Chronic Paraspinal Muscle Injury Model in Rat

    PubMed Central

    Cho, Tack Geun; Kim, Young Baeg

    2016-01-01

    Objective The objective of this study is to establish an animal model of chronic paraspinal muscle injury in rat. Methods Fifty four Sprague-Dawley male rats were divided into experimental group (n=30), sham (n=15), and normal group (n=9). Incision was done from T7 to L2 and paraspinal muscles were detached from spine and tied at each level. The paraspinal muscles were exposed and untied at 2 weeks after surgery. Sham operation was done by paraspinal muscles dissection at the same levels and wound closure was done without tying. Kyphotic index and thoracolumbar Cobb's angle were measured at preoperative, 2, 4, 8, and 12 weeks after the first surgery for all groups. The rats were sacrificed at 4, 8, and 12 weeks after the first surgery, and performed histological examinations. Results At 4 weeks after surgery, the kyphotic index decreased, but, Cobb's angle increased significantly in the experimental group (p<0.05), and then that were maintained until the end of the experiment. However, there were no significant differences of the kyphotic index and Cobb's angle between sham and normal groups. In histological examinations, necrosis and fibrosis were observed definitely and persisted until 12 weeks after surgery. There were also presences of regenerated muscle cells which nucleus is at the center of cytoplasm, centronucleated myofibers. Conclusion Our chronic injury model of paraspinal muscles in rats shows necrosis and fibrosis in the muscles for 12 weeks after surgery, which might be useful to study the pathophysiology of the degenerative thoracolumbar kyphosis or degeneration of paraspinal muscles.

  12. Chronic Paraspinal Muscle Injury Model in Rat

    PubMed Central

    Cho, Tack Geun; Kim, Young Baeg

    2016-01-01

    Objective The objective of this study is to establish an animal model of chronic paraspinal muscle injury in rat. Methods Fifty four Sprague-Dawley male rats were divided into experimental group (n=30), sham (n=15), and normal group (n=9). Incision was done from T7 to L2 and paraspinal muscles were detached from spine and tied at each level. The paraspinal muscles were exposed and untied at 2 weeks after surgery. Sham operation was done by paraspinal muscles dissection at the same levels and wound closure was done without tying. Kyphotic index and thoracolumbar Cobb's angle were measured at preoperative, 2, 4, 8, and 12 weeks after the first surgery for all groups. The rats were sacrificed at 4, 8, and 12 weeks after the first surgery, and performed histological examinations. Results At 4 weeks after surgery, the kyphotic index decreased, but, Cobb's angle increased significantly in the experimental group (p<0.05), and then that were maintained until the end of the experiment. However, there were no significant differences of the kyphotic index and Cobb's angle between sham and normal groups. In histological examinations, necrosis and fibrosis were observed definitely and persisted until 12 weeks after surgery. There were also presences of regenerated muscle cells which nucleus is at the center of cytoplasm, centronucleated myofibers. Conclusion Our chronic injury model of paraspinal muscles in rats shows necrosis and fibrosis in the muscles for 12 weeks after surgery, which might be useful to study the pathophysiology of the degenerative thoracolumbar kyphosis or degeneration of paraspinal muscles. PMID:27651859

  13. Cardiorenal syndrome: role of protein-bound uremic toxins.

    PubMed

    Lekawanvijit, Suree; Krum, Henry

    2015-03-01

    Renal impairment is a strong independent risk factor associated with poor prognosis in cardiovascular disease patients. Renal dysfunction is likely contributed by progressive renal structural damage. Accurate detection of kidney injury in a timely manner as well as increased knowledge of the pathophysiology and mechanisms underlying this injury is of great importance in developing therapeutic interventions for combating renal complications at an early stage. Regarding the role of uremic solutes in the pathophysiology of cardiorenal syndrome, a number of further studies are warranted. There may be uremic solutes discovered from proteomics not yet chemically identified or tested for biological activity. Beyond Protein-bound uremic toxins, uremic solutes in other classes (according to the European Uraemic Toxin Work Group classification) may have adverse cardiorenal effects. Although most small water-soluble solutes and middle molecules can be satisfactorily removed by either conventional or newly developed dialysis strategies, targeting uremic toxins with cardiorenal toxicity at predialysis stage of chronic kidney disease may retard or prevent incident dialysis as well as the initiation/progression of cardiorenal syndrome. PMID:25556308

  14. The Influence of Prebiotic Arabinoxylan Oligosaccharides on Microbiota Derived Uremic Retention Solutes in Patients with Chronic Kidney Disease: A Randomized Controlled Trial

    PubMed Central

    Evenepoel, Pieter; de Loor, Henriette; Delcour, Jan A.; Courtin, Christophe M.; Kuypers, Dirk; Augustijns, Patrick; Verbeke, Kristin; Meijers, Björn

    2016-01-01

    The colonic microbial metabolism is a key contributor to uremic retention solutes accumulating in patients with CKD, relating to adverse outcomes and insulin resistance. Whether prebiotics can reduce intestinal generation of these microbial metabolites and improve insulin resistance in CKD patients not yet on dialysis remains unknown. We performed a randomized, placebo-controlled, double-blind, cross-over study in 40 patients with eGFR between 15 and 45 ml/min/1.73 m2. Patients were randomized to sequential treatment with prebiotic arabinoxylan oligosaccharides (AXOS) (10 g twice daily) and maltodextrin for 4 weeks, or vice versa, with a 4-week wash-out period between both intervention periods. Serum levels and 24h urinary excretion of p-cresyl sulfate, p-cresyl glucuronide, indoxyl sulfate, trimethylamine N-oxide and phenylacetylglutamine were determined at each time point using liquid chromatography—tandem mass spectrometry. In addition, insulin resistance was estimated by the homeostatic model assessment (HOMA-IR). A total of 39 patients completed the study. We observed no significant effect of AXOS on serum p-cresyl sulfate (P 0.42), p-cresyl glucuronide (P 0.59), indoxyl sulfate (P 0.70) and phenylacetylglutamine (P 0.41) and a small, albeit significant decreasing effect on serum trimethylamine N-oxide (P 0.04). There were neither effect of AXOS on 24h urinary excretion of p-cresyl sulfate (P 0.31), p-cresyl glucuronide (P 0.23), indoxyl sulfate (P 0.87) and phenylacetylglutamine (P 0.43), nor on 24h urinary excretion of trimethylamine N-oxide (P 0.97). In addition, we observed no significant change in HOMA-IR (P 0.93). In conclusion, we could not demonstrate an influence of prebiotic AXOS on microbiota derived uremic retention solutes and insulin resistance in patients with CKD not yet on dialysis. Further study is necessary to elucidate whether prebiotic therapy with other characteristics, higher cumulative exposure or in different patient populations may

  15. Damage of hippocampal neurons in rats with chronic alcoholism

    PubMed Central

    Du, Ailin; Jiang, Hongbo; Xu, Lei; An, Na; Liu, Hui; Li, Yinsheng; Zhang, Ruiling

    2014-01-01

    Chronic alcoholism can damage the cytoskeleton and aggravate neurological deficits. However, the effect of chronic alcoholism on hippocampal neurons remains unclear. In this study, a model of chronic alcoholism was established in rats that were fed with 6% alcohol for 42 days. Endogenous hydrogen sulfide content and cystathionine-beta-synthase activity in the hippocampus of rats with chronic alcoholism were significantly increased, while F-actin expression was decreased. Hippocampal neurons in rats with chronic alcoholism appeared to have a fuzzy nuclear membrane, mitochondrial edema, and ruptured mitochondrial crista. These findings suggest that chronic alcoholism can cause learning and memory decline in rats, which may be associated with the hydrogen sulfide/cystathionine-beta-synthase system, mitochondrial damage and reduced expression of F-actin. PMID:25368648

  16. [Atypical hemolytic uremic syndrome].

    PubMed

    Blasco Pelicano, Miquel; Rodríguez de Córdoba, Santiago; Campistol Plana, Josep M

    2015-11-20

    The hemolytic uremic syndrome (HUS) is a clinical entity characterized by thrombocytopenia, non-immune hemolytic anemia and renal impairment. Kidney pathology shows thrombotic microangiopathy (TMA) with endothelial cell injury leading to thrombotic occlusion of arterioles and capillaries. Traditionally, HUS was classified in 2 forms: Typical HUS, most frequently occurring in children and caused by Shiga-toxin-producing bacteria, and atypical HUS (aHUS). aHUS is associated with mutations in complement genes in 50-60% of patients and has worse prognosis, with the majority of patients developing end stage renal disease. After kidney transplantation HUS may develop as a recurrence of aHUS or as de novo disease. Over the last years, many studies have demonstrated that complement dysregulation underlies the endothelial damage that triggers the development of TMA in most of these patients. Advances in our understanding of the pathogenic mechanisms of aHUS, together with the availability of novel therapeutic options, will enable better strategies for the early diagnosis and etiological treatment, which are changing the natural history of aHUS. This review summarizes the aHUS clinical entity and describes the role of complement dysregulation in the pathogenesis of aHUS. Finally, we review the differential diagnosis and the therapeutic options available to patients with aHUS.

  17. Resistant starch alters gut microbiome and metabolomic profiles concurrent with amelioration of chronic kidney disease in rats.

    PubMed

    Kieffer, Dorothy A; Piccolo, Brian D; Vaziri, Nosratola D; Liu, Shuman; Lau, Wei L; Khazaeli, Mahyar; Nazertehrani, Sohrab; Moore, Mary E; Marco, Maria L; Martin, Roy J; Adams, Sean H

    2016-05-01

    Patients and animals with chronic kidney disease (CKD) exhibit profound alterations in the gut environment including shifts in microbial composition, increased fecal pH, and increased blood levels of gut microbe-derived metabolites (xenometabolites). The fermentable dietary fiber high amylose maize-resistant starch type 2 (HAMRS2) has been shown to alter the gut milieu and in CKD rat models leads to markedly improved kidney function. The aim of the present study was to identify specific cecal bacteria and cecal, blood, and urinary metabolites that associate with changes in kidney function to identify potential mechanisms involved with CKD amelioration in response to dietary resistant starch. Male Sprague-Dawley rats with adenine-induced CKD were fed a semipurified low-fiber diet or a high-fiber diet [59% (wt/wt) HAMRS2] for 3 wk (n = 9 rats/group). The cecal microbiome was characterized, and cecal contents, serum, and urine metabolites were analyzed. HAMRS2-fed rats displayed decreased cecal pH, decreased microbial diversity, and an increased Bacteroidetes-to-Firmicutes ratio. Several uremic retention solutes were altered in the cecal contents, serum, and urine, many of which had strong correlations with specific gut bacteria abundances, i.e., serum and urine indoxyl sulfate were reduced by 36% and 66%, respectively, in HAMRS2-fed rats and urine p-cresol was reduced by 47% in HAMRS2-fed rats. Outcomes from this study were coincident with improvements in kidney function indexes and amelioration of CKD outcomes previously reported for these rats, suggesting an important role for microbial-derived factors and gut microbe metabolism in regulating host kidney function.

  18. Creatine kinase reaction rates in rat brain during chronic ischemia.

    PubMed

    Mlynárik, V; Kasparová, S; Liptaj, T; Dobrota, D; Horecký, J; Belan, V

    1998-12-01

    Creatine kinase reaction rates were measured by magnetisation transfer technique in the brain of healthy adult and aged rats and in the rats with mild or severe chronic cerebral ischemia. These measurements indicated that the rate constant of the creatine kinase reaction is significantly reduced in the case of chronic brain ischemia in aged rats. In contrast, occlusion of both carotid arteries in adult rats produced a slight increase in the reaction rate 4 weeks after occlusion. At the same time, corresponding conventional phosphorus magnetic resonance spectra showed negligible changes in signal intensities. PMID:10050942

  19. Uremic toxins originating from colonic microbial metabolism.

    PubMed

    Evenepoel, Pieter; Meijers, Bjorn K I; Bammens, Bert R M; Verbeke, Kristin

    2009-12-01

    Numerous molecules, which are either excreted or metabolized by the kidney, accumulate in patients with chronic kidney disease (CKD). These uremic retention molecules (URMs), contributing to the syndrome of uremia, may be classified according to their site of origin, that is, endogenous metabolism, microbial metabolism, or exogenous intake. It is increasingly recognized that bacterial metabolites, such as phenols, indoles, and amines, may contribute to uremic toxicity. In vitro studies have implicated bacterial URMs in CKD progression, cardiovascular disease, and bone and mineral disorders. Furthermore, several observational studies have demonstrated a link between serum levels of bacterial URMs and clinical outcomes. Bacterial metabolism may therefore be an important therapeutic target in CKD. There is evidence that besides reduced renal clearance, increased colonic generation and absorption explain the high levels of bacterial URMs in CKD. Factors promoting URM generation and absorption include an increased ratio of dietary protein to carbohydrate due to insufficient intake of fiber and/or reduced intestinal protein assimilation, as well as prolonged colonic transit time. Two main strategies exist to reduce bacterial URM levels: interventions that modulate intestinal bacterial growth (e.g., probiotics, prebiotics, dietary modification) and adsorbent therapies that bind bacterial URMs in the intestines to reduce their absorption (e.g., AST-120, sevelamer). The efficacy and clinical benefit of these strategies are currently an active area of interest. PMID:19946322

  20. Renal Response to Chronic Centrifugation in Rats

    NASA Technical Reports Server (NTRS)

    Ortiz, Rudy M.; Wang, T. J.; Corbin, B. J.; Wade, C. E.; Hargens, Alan R. (Technical Monitor)

    1996-01-01

    Previously reported effects of chronic centrifugation on renal function in mammals are contradictory. The present study was conducted as an effort to provide a comprehensive analysis of renal response to chronic centrifugation (12 days at +2 Gz). Sixteen male Sprague-Dawley rats (210-230 g) were used: eight centrifuged (EC) and eight off centrifuge controls (OCC). During centrifugation EC had lower body weight and food consumption. EC showed a decrease (72%) in water intake for the first two days (T1 and T2) followed by significant increases from T4-T6. EC urine output increased two-fold over the first four days, returning to baseline by T9. EC urea excretion was elevated on T3 through T5. Creatinine, Na(+), K(+), and osmolar excretion were lower than OCC over the last four days of the study. Assuming constant plasma osmolarity and creatinine levels, EC free water clearance (C(sub H2O)) was elevated significantly on T4 when the peak urine output was exhibited. EC also had a greater C(sub H2O) over the last four days, associated with a significantly lower osmolar clearance and GFR. The initial diuresis exhibited during centrifugation can be attributed to a reduced water resorption and increased urea excretion. This diuresis was mediated independent of changes in GFR over the first eight days. However, differences in excretion seen after eight days of centrifugation are probably GFR mediated which would imply animals established a new homeostatic setpoint by that time. Centrifugation elicites an acute alteration in fluid homeostasis followed by adaptation within a week.

  1. [Hemolytic uremic syndrome. Treatment of secondary glomerulopathy].

    PubMed

    Caletti, María G; Gallo, Guillermo

    2005-01-01

    Chronic renal failure (CRF) is the most severe complication of hemolytic uremic syndrome (HUS). In 1996, the histological sequence of changes in patients with long lasting oligoanuric periods was clarified. In the last years different therapeutic schemes have been proposed in order to slacken the development of terminal CRF in different renal conditions secondary to diabetes and other diseases. Some of these cases can suffer the onset of renal failure at adolescence. In this review, response to two treatment schemes in different patients with HUS and proteinuria with or without hypertension or renal failure is commented. Early indication of poor sodium diet and strict control of protein intake at the very moment of hospital discharge is strongly recommended, as well as angiotensin II conversion inhibiting enzymes (iACE) at the appearance of proteinuria.

  2. Atypical hemolytic uremic syndrome

    PubMed Central

    2011-01-01

    Hemolytic uremic syndrome (HUS) is defined by the triad of mechanical hemolytic anemia, thrombocytopenia and renal impairment. Atypical HUS (aHUS) defines non Shiga-toxin-HUS and even if some authors include secondary aHUS due to Streptococcus pneumoniae or other causes, aHUS designates a primary disease due to a disorder in complement alternative pathway regulation. Atypical HUS represents 5 -10% of HUS in children, but the majority of HUS in adults. The incidence of complement-aHUS is not known precisely. However, more than 1000 aHUS patients investigated for complement abnormalities have been reported. Onset is from the neonatal period to the adult age. Most patients present with hemolytic anemia, thrombocytopenia and renal failure and 20% have extra renal manifestations. Two to 10% die and one third progress to end-stage renal failure at first episode. Half of patients have relapses. Mutations in the genes encoding complement regulatory proteins factor H, membrane cofactor protein (MCP), factor I or thrombomodulin have been demonstrated in 20-30%, 5-15%, 4-10% and 3-5% of patients respectively, and mutations in the genes of C3 convertase proteins, C3 and factor B, in 2-10% and 1-4%. In addition, 6-10% of patients have anti-factor H antibodies. Diagnosis of aHUS relies on 1) No associated disease 2) No criteria for Shigatoxin-HUS (stool culture and PCR for Shiga-toxins; serology for anti-lipopolysaccharides antibodies) 3) No criteria for thrombotic thrombocytopenic purpura (serum ADAMTS 13 activity > 10%). Investigation of the complement system is required (C3, C4, factor H and factor I plasma concentration, MCP expression on leukocytes and anti-factor H antibodies; genetic screening to identify risk factors). The disease is familial in approximately 20% of pedigrees, with an autosomal recessive or dominant mode of transmission. As penetrance of the disease is 50%, genetic counseling is difficult. Plasmatherapy has been first line treatment until presently

  3. Thyroid hormone receptor binding to DNA and T3-dependent transcriptional activation are inhibited by uremic toxins

    PubMed Central

    Santos, Guilherme M; Pantoja, Carlos J; Costa e Silva, Aluízio; Rodrigues, Maria C; Ribeiro, Ralff C; Simeoni, Luiz A; Lomri, Noureddine; Neves, Francisco AR

    2005-01-01

    Background There is a substantial clinical overlap between chronic renal failure (CRF) and hypothyroidism, suggesting the presence of hypothyroidism in uremic patients. Although CRF patients have low T3 and T4 levels with normal thyroid-stimulating hormone (TSH), they show a higher prevalence of goiter and evidence for blunted tissue responsiveness to T3 action. However, there are no studies examining whether thyroid hormone receptors (TRs) play a role in thyroid hormone dysfunction in CRF patients. To evaluate the effects of an uremic environment on TR function, we investigated the effect of uremic plasma on TRβ1 binding to DNA as heterodimers with the retinoid X receptor alpha (RXRα) and on T3-dependent transcriptional activity. Results We demonstrated that uremic plasma collected prior to hemodialysis (Pre-HD) significantly reduced TRβ1-RXRα binding to DNA. Such inhibition was also observed with a vitamin D receptor (VDR) but not with a peroxisome proliferator-activated receptor gamma (PPARγ). A cell-based assay confirmed this effect where uremic pre-HD ultrafiltrate inhibited the transcriptional activation induced by T3 in U937 cells. In both cases, the inhibitory effects were reversed when the uremic plasma and the uremic ultrafiltrate were collected and used after hemodialysis (Post-HD). Conclusion These results suggest that dialyzable toxins in uremic plasma selectively block the binding of TRβ1-RXRα to DNA and impair T3 transcriptional activity. These findings may explain some features of hypothyroidism and thyroid hormone resistance observed in CRF patients. PMID:15807894

  4. Hypothalamic circuit regulating colonic transit following chronic stress in rats.

    PubMed

    Yoshimoto, Sazu; Cerjak, Diana; Babygirija, Reji; Bulbul, Mehmet; Ludwig, Kirk; Takahashi, Toku

    2012-03-01

    Although acute stress accelerates colonic transit, the effect of chronic stress on colonic transit remains unclear. In this study, rats received repeated restraint stress (chronic homotypic stress) or various types of stress (chronic heterotypic stress) for 5 and 7 days, respectively. Vehicle saline, oxytocin (OXT), OXT receptor antagonist or corticotropin-releasing factor (CRF) receptor antagonists were administered by intracerebroventricular (ICV) injection prior to restraint stress for 90 min. Immediately after the stress exposure, the entire colon was removed and the geometric center (GC) of Na51CrO4 (a nonabsorbable radioactive marker; 0.5 μCi) distribution was calculated to measure the transit. Gene expression of OXT and CRF in the paraventricular nucleus (PVN) was evaluated by in situ hybridization. Accelerated colonic transit with the acute stressor was no longer observed following chronic homotypic stress. This restored colonic transit was reversed by ICV injection of an OXT antagonist. In contrast, chronic heterotypic stress significantly accelerated colonic transit, which was attenuated by ICV injection of OXT and by a CRF receptor 1 antagonist. OXT mRNA expression in the PVN was significantly increased following chronic homotypic stress, but not chronic heterotypic stress. However, CRF mRNA expression in the PVN was significantly increased following acute and chronic heterotypic stress, but not chronic homotypic stress. These results indicate that central OXT and CRF play a pivotal role in mediating the colonic dysmotility following chronic stress in rats.

  5. Chronic administration of sildenafil improves erectile function in a rat model of chronic renal failure.

    PubMed

    Gurbuz, Nilgun; Kol, Arif; Ipekci, Tumay; Ates, Erhan; Baykal, Asli; Usta, Mustafa F

    2015-01-01

    The relationship between erectile dysfunction (ED) and chronic renal failure (CRF) has been reported in several studies. This study aimed to investigate whether the chronic use of sildenafil could enhance the erectile capacity in CRF-induced rats. In addition, we assessed the effect of that treatment on certain molecules, which have been suggested to play crucial roles in erectile physiology and CRF-related ED as well. Three groups of animals were utilized: (1) age-matched control rats, (2) CRF-induced rats, (3) CRF-induced rats treated with chronic administration of sildenafil (5 mg kg-1 p.o. for 6 weeks [treatment started after 6 weeks of CRF induction]). At 3 months, all animals underwent cavernosal nerve stimulation (CNS) to assess erectile function. Penile tissue advanced glycation end products (AGE's)/5-hydroxymethyl-2-furaldehyde, malondialdehyde (MDA), cGMP (ELISA), inducible nitric oxide synthase (iNOS) and neuronal NOS (nNOS) (Western blot) analyses were performed in all rat groups. CRF-induced rats had a significant decrease in erectile function when compared to control rats (P < 0.05). The increase in both intracavernosal pressure (ICP) and area under the curve of CRF-induced rats treated with sildenafil (Group 3) was greater than CRF-induced rats (Group 2). Additionally, sildenafil treatment decreased AGE, MDA and iNOS levels, while it preserved nNOS and cGMP contents in CRF-induced penile tissue. Decreased AGE, MDA, iNOS and increased nNOS, cGMP levels at the sildenafil-treated group increased both ICP and Total ICP to CNS, which led to improve erectile function in CRF-induced rats. The results of the present study revealed the therapeutic effect of chronic sildenafil administration on erectile function in CRF-induced rats.

  6. [The uremic toxin, indoxyl sulfate, signifies cardio-renal risk and intestinal-renal relationship].

    PubMed

    Kiss, István

    2011-10-23

    Uremic syndrome and condition is primarily a result of kidney failure in which uremic toxins are accumulated. More and more attention is paid to possibilities for removal of uremic toxins, which not only means dialysis, but also takes into account special dietary considerations and treatments, which aim to absorb the toxins or reduce their production. These uremic toxins, which also increase the cardiovascular risks, play a major part in morbidity and mortality of patients suffering from chronic renal failure and those receiving renal replacement therapy. One of them is a member of the indol group, the indoxyl sulfate. This toxin is difficult to remove with dialysis and is an endogenous protein-bound uremic toxin. Today we know that indoxyl sulfate is a vascular-nephrotoxic agent, which is able to enhance progression of cardiovascular and renal diseases. It is of particular importance that because of its redox potency, this toxin causes oxidative stress and antioxidant effects at the same time and, on top of that, it is formed in the intestinal system. Its serum concentration depends on the nutrition and the tubular function and, therefore, it can also signal the progression of chronic renal failure independently of glomerular filtration rate. Successful removal of indoxyl sulfate reduces the morbidity and mortality and improves survival. Therefore, it could be a possible target or area to facilitate the reduction of uremia in chronic renal failure. The use of probiotics and prebiotics with oral adsorbents may prove to be a promising opportunity to reduce indoxyl sulfate accumulation. PMID:21983398

  7. Chronic effects of mercuric chloride ingestion on rat adrenocortical function

    SciTech Connect

    Agrawal, R.; Chansouria, J.P.N. )

    1989-09-01

    Mercurial contamination of environment has increased. Mercury accumulates in various organs and adversely affects their functions. Some of the most prominent toxic effects of inorganic mercury compounds include neurotoxicity, hepatotoxicity and nephrotoxicity. Besides this, mercury has also been reported to affect various endocrine glands like pituitary, thyroid, gonadal and adrenal glands. There have been no reports on the toxic effects of chronic oral administration of varying doses of mercuric chloride on adrenocortical function in albino rats. The present work was undertaken to study the adrenocortical response to chronic oral administration of mercuric chloride of varying dose and duration in albino rats.

  8. Experimental rat models of chronic allograft nephropathy: a review

    PubMed Central

    Shrestha, Badri; Haylor, John

    2014-01-01

    Chronic allograft nephropathy (CAN) is the leading cause of late allograft loss after renal transplantation (RT), which continues to remain an unresolved problem. A rat model of CAN was first described in 1969 by White et al. Although the rat model of RT can be technically challenging, it is attractive because the pathogenesis of CAN is similar to that following human RT and the pathological features of CAN develop within months as compared with years in human RT. The rat model of RT is considered as a useful investigational tool in the field of experimental transplantation research. We have reviewed the literature on studies of rat RT reporting the donor and recipient strain combinations that have investigated resultant survival and histological outcomes. Several different combinations of inbred and outbred rat combinations have been reported to investigate the multiple aspects of transplantation, including acute rejection, cellular and humoral rejection mechanisms and their treatments, CAN, and potential targets for its prevention. PMID:25092995

  9. Chronic inhalation exposure of rats to nitromethane.

    PubMed

    Griffin, T B; Coulston, F; Stein, A A

    1996-07-01

    Male and female Long-Evans rats were housed in inhalation chambers and exposed to vapors of nitromethane (NM) at either 100 or 200 ppm. The animals were exposed 7 hr per day, 5 days per week for 2 years. Control groups of rats were also housed in a similar inhalation chamber, but NM was not introduced into the chamber. The animals were observed daily for signs of pharmacologic or toxicologic effect and body weights were recorded periodically. At the 2-year termination of the exposure period, clinical laboratory examinations (serum chemistry and hematology) were performed on selected animals and all surviving animals were sacrificed. All animals were necropsied and subjected to a thorough histopathologic examination. During the study there were no pharmacologic effects from exposure to NM at either 100 or 200 ppm. There was no effect on mortality on either sex at either exposure level. Body weights of male rats exposed to NM were not significantly different from those of control rats, but the body weights of female rats of both exposure groups were slightly less than their controls. There was no effect of exposure of rats of either sex to either level of NM on hematology. There were no clinically significant effects on serum chemistry. There were no effects of exposure to NM on organ weights. There were no significant differences in the nonneoplastic or neoplastic pathology related to exposure to NM. PMID:8812175

  10. Epigenetics and the uremic phenotype: a matter of balance.

    PubMed

    Stenvinkel, Peter; Ekström, Tomas J

    2008-01-01

    Epigenetics, which is the study of changes in gene expression that occur without changes in DNA sequence, is a novel discipline that has languished in the shadow of its genomic big brother. So far, studies of the epigenome have attracted little interest in nephrology. Chronic kidney disease is an example of complex disease in which the phenotype arises from a combination of environmental and heritable factors. Evidence suggests that the contribution made by the environment may be mediated via modifications of the epigenome. In the uremic milieu, several features such as inflammation, dyslipidemia, hyperhomocysteinema, oxidative stress as well as vitamin and nutritional deficiencies may affect aberrant global DNA methylation. However, as hyperhomocysteinemia seems to promote global DNA hypomethylation and persistent inflammation DNA hypermethylation, the effects of the uremic milieu on aberrant global DNA methylation may be complex and context-sensitive. It should be emphasized that in analogy to the unspecific nature of fever, aberrant global DNA methylation is only a sign of a generalized epigenetic dysregulation. Thus, to provide better understanding of the effects of aberrant DNA methylation on the uremic phenotype, further studies evaluating site-specific information on methylation in various candidate genes are needed. The science of epigenetics may not only uncover etiologic and pathogenic mechanisms in uremia, but may also be of help to develop novel treatment strategies targeting the unacceptable high death risk in cardiovascular complications in this patient population.

  11. Effect of chronic hypoxia on penile erectile function in rats.

    PubMed

    Yu, D P; Liu, X H; Wei, A Y

    2015-09-08

    We examined the relationship between chronic hypoxia and erectile dysfunction in rat and its possible pathogenic mechanism. Forty-eight white male adult Sprague-Dawley rats were randomly divided into a test group and a control group. In accordance with the experimental time (2, 6, and 10 weeks), each group was divided into 3 subgroups, with 8 rats in each subgroup. Rats in the test group were fed in an airtight hypoxia cabin, while rats in the control group were maintained in a normal environment, with other conditions kept the same. At 2, 6, and 10 weeks, the rats in each group were observed for erectile function. Affinity purification was used to detect neural nitric oxide synthase (nNOS)-positive nerve fibers and endothelial nitric oxide synthase (eNOS) expression. After hypoxia, erectile frequency decreased significantly compared to before hypoxia (P < 0.001). Comparison of the test group and control group revealed a significant difference in the quantity of nNOS-positive nerve fiber and eNOS protein expression (P < 0.01). Hypoxia may influence erectile function and nNOS and eNOS expression in rats. The decrease in the quantity of nNOS nerve fibers and expression of eNOS may contribute to erectile dysfunction under hypoxic conditions in rats.

  12. Brain perfusion in acute and chronic hyperglycemia in rats

    SciTech Connect

    Kikano, G.E.; LaManna, J.C.; Harik, S.I. )

    1989-08-01

    Recent studies show that acute and chronic hyperglycemia cause a diffuse decrease in regional cerebral blood flow and that chronic hyperglycemia decreases the brain L-glucose space. Since these changes can be caused by a decreased density of perfused brain capillaries, we used 30 adult male Wistar rats to study the effect of acute and chronic hyperglycemia on (1) the brain intravascular space using radioiodinated albumin, (2) the anatomic density of brain capillaries using alkaline phosphatase histochemistry, and (3) the fraction of brain capillaries that are perfused using the fluorescein isothiocyanate-dextran method. Our results indicate that acute and chronic hyperglycemia do not affect the brain intravascular space nor the anatomic density of brain capillaries. Also, there were no differences in capillary recruitment among normoglycemic, acutely hyperglycemic, and chronically hyperglycemic rats. These results suggest that the shrinkage of the brain L-glucose space in chronic hyperglycemia is more likely due to changes in the blood-brain barrier permeability to L-glucose.

  13. A new apparatus for chronic intravenous infusion in unrestrained rats.

    PubMed

    Takeyama, H; Yura, J; Miyaike, H; Ishikawa, M; Mizuno, H; Taniguchi, M; Hanai, T; Mizuno, A; Shinagawa, N; Kato, F

    1988-01-01

    A new apparatus incorporating a unique type of swivel device was devised for chronic intravenous infusion in unrestrained rats. The swivel requires very little torque for rotation, ie, one-fourth that of the standard swivel, yet is 1/30 as expensive. A coil spring tube, located between the swivel and the catheter, allows the rat unhampered movement within the metabolic cage. Because the catheter follows the rats' movements freely, only two silk sutures are required to secure it to the animal. No statistically significant differences between experimental and control rats were observed in terms of body weight gain, food intake, nitrogen balance, or caloric efficiency. This apparatus should prove useful in many areas of research.

  14. [Establishment of a rat chronic asthma model and its evaluation].

    PubMed

    Liu, Zhong-Cheng; Zhang, Yan-Fen

    2010-06-01

    This study is to establish a rat chronic asthma model. Sensitive SD rats were selected through histamine challenge. The asthmatic groups were sensitized by ih and ip with OVA, aluminium hydroxide gel and inactivated bacillus pertussis on day 1 and 14. From day 21, acute asthmatic group was aerosolized 1% OVA for 1 week, chronic asthmatic group was aerosolized 0.1% OVA for 12 weeks. The control groups received saline as the substitution of OVA. Twenty four hours after the last provocation, physiological monitoring equipment was used to detect the pulmonary function, then the rats were sacrificed. Bronchoalveolar lavage fluid (BALF) was collected to calculate the ratio of different inflammatory cells. ELISA was used to detect total IgE and OVA-specific IgE in serum. Microscopy was conducted to observe the histopathology of lung stained with haematoxylin and eosin staining. Collagen fibers were detected using Picric acid-Sirius red staining technique. The optical density at 610 nm of extractive from locus caeruleus was detected by passive cutaneous anaphylaxis (PCA). The results showed that the asthmatic characteristics were significantly developed in model groups, but not in control groups. Chronic asthmatic group had significantly higher indexes than acute asthmatic group, including the thickness of airway smooth muscle and bronchial basement membrane, and goblet cell hyperplasia, the area of collagen in airways, A610 of extractive from locus caeruleus, the concentration of total IgE and OVA-specific IgE in serum. However, inflammatory cell infiltrate in lungs and the percentage of eosinophils of white blood cells in BALF were lower in chronic asthmatic group than those in acute asthmatic group. Respiratory rate and respiratory flow showed no significant difference in both model groups. In conclusion, the rat chronic asthma model is established by the way in this study, which is comparable to the physiopathologic characteristics of human asthma.

  15. Effects of Mild Chronic Intermittent Cold Exposure on Rat Organs.

    PubMed

    Wang, Xiaohui; Che, Honglei; Zhang, Wenbin; Wang, Jiye; Ke, Tao; Cao, Rui; Meng, Shanshan; Li, Dan; Weiming, Ouyang; Chen, Jingyuan; Luo, Wenjing

    2015-01-01

    Cold adaptation is a body's protective response to cold stress. Mild chronic intermittent cold (CIC) exposure has been used to generate animal models for cold adaptation studies. However, the effects of mild CIC exposure on vital organs are not completely characterized. In the present study, we exposed rats to mild CIC for two weeks, and then measured the body weights, the weights of brown adipose tissue (BAT), the levels of ATP and reactive oxygen species (ROS) in the brains, livers, hearts, muscles and BATs. Rats formed cold adaptation after exposure to CIC for two weeks. Compared to rats of the control group that were hosted under ambient temperature, rats exposed to mild CIC showed a lower average body weight, but a higher weight of brown adipose tissue (BAT). Rats exposed to CIC for two weeks also exhibited higher levels of ATP and ROS in all examined organs as compared to those of the control group. In addition, we determined the expression levels of cold-inducible RNA binding protein (Cirbp) and thioredoxin (TRX) in rat tissues after 2 weeks of CIC exposure. Both Cirbp and TRX were increased, suggesting a role of these two proteins for establishment of cold adaptation. Together, this study reveals the effects of mild CIC exposure on vital organs of rats during CIC exposure.

  16. Effects of Mild Chronic Intermittent Cold Exposure on Rat Organs

    PubMed Central

    Wang, Xiaohui; Che, Honglei; Zhang, Wenbin; Wang, Jiye; Ke, Tao; Cao, Rui; Meng, Shanshan; Li, Dan; Weiming, Ouyang; Chen, Jingyuan; Luo, Wenjing

    2015-01-01

    Cold adaptation is a body's protective response to cold stress. Mild chronic intermittent cold (CIC) exposure has been used to generate animal models for cold adaptation studies. However, the effects of mild CIC exposure on vital organs are not completely characterized. In the present study, we exposed rats to mild CIC for two weeks, and then measured the body weights, the weights of brown adipose tissue (BAT), the levels of ATP and reactive oxygen species (ROS) in the brains, livers, hearts, muscles and BATs. Rats formed cold adaptation after exposure to CIC for two weeks. Compared to rats of the control group that were hosted under ambient temperature, rats exposed to mild CIC showed a lower average body weight, but a higher weight of brown adipose tissue (BAT). Rats exposed to CIC for two weeks also exhibited higher levels of ATP and ROS in all examined organs as compared to those of the control group. In addition, we determined the expression levels of cold-inducible RNA binding protein (Cirbp) and thioredoxin (TRX) in rat tissues after 2 weeks of CIC exposure. Both Cirbp and TRX were increased, suggesting a role of these two proteins for establishment of cold adaptation. Together, this study reveals the effects of mild CIC exposure on vital organs of rats during CIC exposure. PMID:26327811

  17. Uremic pruritus treated successfully with the Goeckerman Program.

    PubMed

    Nakamura, Mio; Koo, John; Bhutani, Tina

    2016-01-01

    Uremic pruritus (UP) is a common condition among patients with chronic kidney disease (CKD) on hemodialysis (HD). We report 19 a case of severe UP recalcitrant to conventional therapy including topical corticosteroids, anti-histamines, and phototherapy, 20 which was treated successfully with the Goeckerman regimen consisting of topical coal tar, topical corticosteroids, and broadband 21 UVB (BB-UVB). Little is known about the pathophysiology of UP, and there is currently no consensus or evidence-based 22 treatments for UP. Although further studies are necessary, Goeckerman therapy may be a promising treatment option when 23 available for severe UP intractable to conventional therapies. PMID:27617950

  18. Uremic pruritus treated successfully with the Goeckerman Program.

    PubMed

    Nakamura, Mio; Koo, John; Bhutani, Tina

    2016-01-01

    Uremic pruritus (UP) is a common condition among patients with chronic kidney disease (CKD) on hemodialysis (HD). We report 19 a case of severe UP recalcitrant to conventional therapy including topical corticosteroids, anti-histamines, and phototherapy, 20 which was treated successfully with the Goeckerman regimen consisting of topical coal tar, topical corticosteroids, and broadband 21 UVB (BB-UVB). Little is known about the pathophysiology of UP, and there is currently no consensus or evidence-based 22 treatments for UP. Although further studies are necessary, Goeckerman therapy may be a promising treatment option when 23 available for severe UP intractable to conventional therapies.

  19. Chronic administration of quercetin prevent spatial learning and memory deficits provoked by chronic stress in rats.

    PubMed

    Mohammadi, Hadis Said; Goudarzi, Iran; Lashkarbolouki, Taghi; Abrari, Kataneh; Elahdadi Salmani, Mahmoud

    2014-08-15

    There are several reports that cognitive impairment is observed in stress related disorders and chronic stress impairs learning and memory. However, very few studies have looked into the possible ways of preventing this stress-induced deficit. This research study was conducted to evaluate the effects of quercetin, a natural flavonoid, with strong antioxidant and free radical scavenger properties, on chronic stress induced learning and memory deficits and oxidative stress in hippocampus. For chronic stress, rats were restrained daily for 6h/day (from 9:00 to 15:00) for 21 days in well-ventilated plexiglass tubes without access to food and water. The animals were injected with quercetin or vehicle 60 min before restraint stress over a period of 21 days. Then, rats trained with six trials per day for 6 consecutive days in the water maze. On day 28, a probe test was done to measure memory retention. In addition, oxidative stress markers in the hippocampus were evaluated. Results of this study demonstrated that chronic stress exposure rats exhibited higher escape latency during training trials and reduced time spent in target quadrant, higher escape location latency and average proximity in probe trial test. Quercetin (50mg/kg) treatment during restraint stress (21 days) markedly decreased escape latency and increased time spent in target quadrant during Morris water maze task. In comparison to vehicle treated group, chronic-stress group had significantly higher malondialdehyde (MDA) levels, significantly higher superoxide dismutase (SOD) activity and significantly lower glutathione peroxidase (GPx) activity in the hippocampus. Quercetin treatment caused a significant decrease in the hippocampus MDA levels and improves SOD and GPx activities in stressed animals. Finally, quercetin significantly decreased plasma corticosterone levels in stressed animals. Based on results of this study, chronic stress has detrimental effects on learning and memory and quercetin treatment

  20. The impact of chronic stress on the rat brain lipidome.

    PubMed

    Oliveira, T G; Chan, R B; Bravo, F V; Miranda, A; Silva, R R; Zhou, B; Marques, F; Pinto, V; Cerqueira, J J; Di Paolo, G; Sousa, N

    2016-01-01

    Chronic stress is a major risk factor for several human disorders that affect modern societies. The brain is a key target of chronic stress. In fact, there is growing evidence indicating that exposure to stress affects learning and memory, decision making and emotional responses, and may even predispose for pathological processes, such as Alzheimer's disease and depression. Lipids are a major constituent of the brain and specifically signaling lipids have been shown to regulate brain function. Here, we used a mass spectrometry-based lipidomic approach to evaluate the impact of a chronic unpredictable stress (CUS) paradigm on the rat brain in a region-specific manner. We found that the prefrontal cortex (PFC) was the area with the highest degree of changes induced by chronic stress. Although the hippocampus presented relevant lipidomic changes, the amygdala and, to a greater extent, the cerebellum presented few lipid changes upon chronic stress exposure. The sphingolipid and phospholipid metabolism were profoundly affected, showing an increase in ceramide (Cer) and a decrease in sphingomyelin (SM) and dihydrosphingomyelin (dhSM) levels, and a decrease in phosphatidylethanolamine (PE) and ether phosphatidylcholine (PCe) and increase in lysophosphatidylethanolamine (LPE) levels, respectively. Furthermore, the fatty-acyl profile of phospholipids and diacylglycerol revealed that chronic stressed rats had higher 38 carbon(38C)-lipid levels in the hippocampus and reduced 36C-lipid levels in the PFC. Finally, lysophosphatidylcholine (LPC) levels in the PFC were found to be correlated with blood corticosterone (CORT) levels. In summary, lipidomic profiling of the effect of chronic stress allowed the identification of dysregulated lipid pathways, revealing putative targets for pharmacological intervention that may potentially be used to modulate stress-induced deficits.

  1. Daily water and electrolyte balance in chronically hyperprolactinaemic rats.

    PubMed

    Kaufman, S; Mackay, B J; Scott, J Z

    1981-12-01

    1. Chronic hyperprolactinaemia was induced in eight male rats by implantation of anterior pituitary glands from inbred female rats. The ten control rats underwent sham operations. 2. The spontaneous 24 hr water intake of hyperprolactinaemic rats was greater than that of the controls. Intake was increased only at night. 3. The increased water intake was independent of food intake and was not secondary to increased salt intake. 4. When prolactin secretion was inhibited with bromocriptine, there was a parallel fall in water intake and plasma prolactin levels in the experimental animals to the levels observed in the controls. 5. Urine volume was greater and urine osmolality lower in the hyperprolactinaemic rats than in the controls during both day and night. 6. In the evening, plasma osmolality was lower in the hyperprolactinaemic animals than in the controls. No such difference was observed in the morning. 7. Blood volume was greater in the hyperprolactinaemic rats than in the controls, but the haematocrits were the same. 8. These findings indicate prolactin may have a primary dipsogenic activity.

  2. An Enlarged Profile of Uremic Solutes

    PubMed Central

    Tanaka, Hisae; Sirich, Tammy L.; Plummer, Natalie S.; Weaver, Daniel S.; Meyer, Timothy W.

    2015-01-01

    Better knowledge of the uremic solutes that accumulate when the kidneys fail could lead to improved renal replacement therapy. This study employed the largest widely available metabolomic platform to identify such solutes. Plasma and plasma ultrafiltrate from 6 maintenance hemodialysis (HD) patients and 6 normal controls were first compared using a platform combining gas and liquid chromatography with mass spectrometry. Further studies compared plasma from 6 HD patients who had undergone total colectomy and 9 with intact colons. We identified 120 solutes as uremic including 48 that had not been previously reported to accumulate in renal failure. Combination of the 48 newly identified solutes with those identified in previous reports yielded an extended list of more than 270 uremic solutes. Among the solutes identified as uremic in the current study, 9 were shown to be colon-derived, including 6 not previously identified as such. Literature search revealed that many uremic phenyl and indole solutes, including most of those shown to be colon-derived, come from plant foods. Some of these compounds can be absorbed directly from plant foods and others are produced by colon microbial metabolism of plant polyphenols that escape digestion in the small intestine. A limitation of the metabolomic method was that it underestimated the elevation in concentration of uremic solutes which were measured using more quantitative assays. PMID:26317986

  3. Regulation of body mass in rats exposed to chronic acceleration

    NASA Technical Reports Server (NTRS)

    Pitts, G. C.; Bull, L. S.; Oyama, J.

    1975-01-01

    Female rats approximately 6 mo old were chronically centrifuged for up to 30 days at 2.76 G or 3.18 G and sacrificed at intervals for body-composition study. Both fat and the fat-free body mass (FFBM) were reduced during the 1st wk of centrifugation, with the fat showing considerably more variation both within and between groups. The FFBM was reduced below control level to the same extent in rats fed commercial chow, a high-fat diet, or a high-protein diet or in rats prefasted to produce a body-mass deficit at the start of centrifugation. There were no centrifugation-associated changes in body water content. It was concluded that body fat showed no evidence of regulation, FFBM is regulated at any constant level of acceleration between 1 and 4.15 G, and the change in FFBM induced by a change in acceleration is probably not regulated.

  4. Effects of chronic stress on sleep in rats.

    PubMed

    Kant, G J; Pastel, R H; Bauman, R A; Meininger, G R; Maughan, K R; Robinson, T N; Wright, W L; Covington, P S

    1995-02-01

    The present study was conducted to determine the effects of chronic stress on sleep using a rodent paradigm of around-the-clock signalled intermittent foot shock in which some rats can pull a chain to avoid/escape shock while another group of rats is yoked to the first group. We measured sleep using telemetry; four-channel EEG was collected 24 h/day in rats during 2 prestress days; days 1, 2, 3, 7, and 14 during chronic stress; and 3 poststress days. States of REM sleep, non-REM (NREM) sleep, and waking were scored for each 15-s period of the EEG recordings. During the prestress period, rats slept (REM plus NREM) 55% of available time during the light hours and 34% of the dark hours with the remainder represented by waking. On the first day of stress, total sleep and, especially REM sleep, decreased markedly. By the second day of stress, only REM sleep in the controllable stress group (but not the uncontrollable stress group) was still significantly decreased compared to prestress levels, and REM sleep returned to baseline levels by day 7 of stress. The recovery of sleep quantity was accomplished by increased sleep during the dark hours, resulting in a long-lasting disruption of normal circadian sleep patterning.

  5. Sex differences in chronic stress effects on memory in rats.

    PubMed

    Luine, Victoria

    2002-09-01

    Recent studies in rodent models and in humans have shown that the status of both the gonadal and adrenal axes (hypothalamic-pituitary-gonadal, HPG and hypothalamic-pituitary-adrenal, HPA, respectively) can influence learning and memory function. In this article, the effects of activating the HPA axis (stress) on performance of memory tasks in rats are reviewed. More importantly, results are presented which show that chronic stress has a different impact on performance of these tasks depending upon the sex of the rat. These observations are novel and potentially important since few studies, animal or human, have utilized females as subjects in studies of the stress response. Sex differences in the effects of chronic stress on memory were investigated in rats using an object recognition task and two spatial memory tasks, radial arm maze and object location. Given the same chronic stress--21 days of restraint for 6 h each day--males were impaired in all of the memory tests while females showed enhanced performance of the spatial memory tasks and no changes in object recognition performance. Levels of neurotransmitters and metabolites were measured in brain areas important for cognition in the subjects in order to determine neural systems that may respond to stress and mediate the cognitive responses. These results show that responses of monoamine and amino acid containing neural systems may contribute to or underlie sex differences in stress effects on cognition. Stress decreased dopaminergic activity in the frontal cortex and amygdala of males but not females; whereas, in CA3 of the hippocampus, stress increased levels of 5-HT and norepinephrine in females, but not males, and increased GABA in males, but not females. Finally, a possible role for estradiol in mediating sexually differentiated responses to stress was examined. Behavioral and neurochemical evaluations in ovariectomized, stressed females, with or without estrogen replacement, suggest that sex differences

  6. Chronic Methamphetamine Effects on Brain Structure and Function in Rats.

    PubMed

    Thanos, Panayotis K; Kim, Ronald; Delis, Foteini; Ananth, Mala; Chachati, George; Rocco, Mark J; Masad, Ihssan; Muniz, Jose A; Grant, Samuel C; Gold, Mark S; Cadet, Jean Lud; Volkow, Nora D

    2016-01-01

    Methamphetamine (MA) addiction is a growing epidemic worldwide. Chronic MA use has been shown to lead to neurotoxicity in rodents and humans. Magnetic resonance imaging (MRI) studies in MA users have shown enlarged striatal volumes and positron emission tomography (PET) studies have shown decreased brain glucose metabolism (BGluM) in the striatum of detoxified MA users. The present study examines structural changes of the brain, observes microglial activation, and assesses changes in brain function, in response to chronic MA treatment. Rats were randomly split into three distinct treatment groups and treated daily for four months, via i.p. injection, with saline (controls), or low dose (LD) MA (4 mg/kg), or high dose (HD) MA (8 mg/kg). Sixteen weeks into the treatment period, rats were injected with a glucose analog, [18F] fluorodeoxyglucose (FDG), and their brains were scanned with micro-PET to assess regional BGluM. At the end of MA treatment, magnetic resonance imaging at 21T was performed on perfused rats to determine regional brain volume and in vitro [3H]PK 11195 autoradiography was performed on fresh-frozen brain tissue to measure microglia activation. When compared with controls, chronic HD MA-treated rats had enlarged striatal volumes and increases in [3H]PK 11195 binding in striatum, the nucleus accumbens, frontal cortical areas, the rhinal cortices, and the cerebellar nuclei. FDG microPET imaging showed that LD MA-treated rats had higher BGluM in insular and somatosensory cortices, face sensory nucleus of the thalamus, and brainstem reticular formation, while HD MA-treated rats had higher BGluM in primary and higher order somatosensory and the retrosplenial cortices, compared with controls. HD and LD MA-treated rats had lower BGluM in the tail of the striatum, rhinal cortex, and subiculum and HD MA also had lower BGluM in hippocampus than controls. These results corroborate clinical findings and help further examine the mechanisms behind MA

  7. Chronic Methamphetamine Effects on Brain Structure and Function in Rats

    PubMed Central

    Thanos, Panayotis K.; Kim, Ronald; Delis, Foteini; Ananth, Mala; Chachati, George; Rocco, Mark J.; Masad, Ihssan; Muniz, Jose A.; Grant, Samuel C.; Gold, Mark S.; Cadet, Jean Lud; Volkow, Nora D.

    2016-01-01

    Methamphetamine (MA) addiction is a growing epidemic worldwide. Chronic MA use has been shown to lead to neurotoxicity in rodents and humans. Magnetic resonance imaging (MRI) studies in MA users have shown enlarged striatal volumes and positron emission tomography (PET) studies have shown decreased brain glucose metabolism (BGluM) in the striatum of detoxified MA users. The present study examines structural changes of the brain, observes microglial activation, and assesses changes in brain function, in response to chronic MA treatment. Rats were randomly split into three distinct treatment groups and treated daily for four months, via i.p. injection, with saline (controls), or low dose (LD) MA (4 mg/kg), or high dose (HD) MA (8 mg/kg). Sixteen weeks into the treatment period, rats were injected with a glucose analog, [18F] fluorodeoxyglucose (FDG), and their brains were scanned with micro-PET to assess regional BGluM. At the end of MA treatment, magnetic resonance imaging at 21T was performed on perfused rats to determine regional brain volume and in vitro [3H]PK 11195 autoradiography was performed on fresh-frozen brain tissue to measure microglia activation. When compared with controls, chronic HD MA-treated rats had enlarged striatal volumes and increases in [3H]PK 11195 binding in striatum, the nucleus accumbens, frontal cortical areas, the rhinal cortices, and the cerebellar nuclei. FDG microPET imaging showed that LD MA-treated rats had higher BGluM in insular and somatosensory cortices, face sensory nucleus of the thalamus, and brainstem reticular formation, while HD MA-treated rats had higher BGluM in primary and higher order somatosensory and the retrosplenial cortices, compared with controls. HD and LD MA-treated rats had lower BGluM in the tail of the striatum, rhinal cortex, and subiculum and HD MA also had lower BGluM in hippocampus than controls. These results corroborate clinical findings and help further examine the mechanisms behind MA

  8. Impact of Iodinated Contrast on Renal Function and Hemodynamics in Rats with Chronic Hyperglycemia and Chronic Kidney Disease.

    PubMed

    Fernandes, Sheila Marques; Martins, Daniel Malisani; da Fonseca, Cassiane Dezoti; Watanabe, Mirian; Vattimo, Maria de Fátima Fernandes

    2016-01-01

    Iodinated contrast (IC) is clinically used in diagnostic and interventional procedures, but its use can result in contrast-induced acute kidney injury (CI-AKI). Chronic kidney disease (CKD) and chronic hyperglycemia (CH) are important predisposing factors to CI-AKI. The aim of this study was to investigate the impact of iodinated contrast on the renal function and hemodynamics in rats with chronic hyperglycemia and chronic kidney disease. A total of 30 rats were divided into six groups; Sham: control of chronic renal disease; Citrate: control of chronic hyperglycemia (CH); Nx5/6: rats with 5/6 nephrectomy; Chronic Hyperglycemia: rats receiving Streptozotocin 65 mg/kg; Nx5/6 + IC: rats Nx5/6 received 6 mL/kg of IC; CH + IC: Chronic hyperglycemia rats receiving 6 mL/kg of IC. Renal function (inulin clearance; urinary neutrophil gelatinase-associated lipocalin, NGAL) and hemodynamics (arterial blood pressure; renal blood flow; renal vascular resistance) were evaluated. Iodinated contrast significantly increased urinary NGAL and reduced inulin clearance, while the hemodynamics parameters showed changes in arterial blood pressure, renal blood flow, and renal vascular resistance in both CKD and CH groups. The results suggest that the iodinated contrast in risk factors models has important impact on renal function and hemodynamics. NGAL was confirmed to play a role of highlight in diagnosis of CI-AKI. PMID:27034930

  9. Oral hydrogen water prevents chronic allograft nephropathy in rats.

    PubMed

    Cardinal, Jon S; Zhan, Jianghua; Wang, Yinna; Sugimoto, Ryujiro; Tsung, Allan; McCurry, Kenneth R; Billiar, Timothy R; Nakao, Atsunori

    2010-01-01

    Reactive oxygen species (ROS) contribute to the development of interstitial fibrosis and tubular atrophy seen in chronic allograft nephropathy (CAN). As molecular hydrogen gas can act as a scavenger of ROS, we tested the effect of treatment with hydrogen water (HW) in a model of kidney transplantation, in which allografts from Lewis rats were orthotopically transplanted into Brown Norway recipients that had undergone bilateral nephrectomy. Molecular hydrogen was dissolved in water and recipients were given HW from day 0 until day 150. Rats that were treated with regular water (RW) gradually developed proteinuria and their creatinine clearance declined, ultimately leading to graft failure secondary to CAN. In contrast, treatment with HW improved allograft function, slowed the progression of CAN, reduced oxidant injury and inflammatory mediator production, and improved overall survival. Inflammatory signaling pathways, such as mitogen-activated protein kinases, were less activated in renal allografts from HW-treated rats as compared with RW-treated rats. Hence, oral HW is an effective antioxidant and antiinflammatory agent that prevented CAN, improved survival of rat renal allografts, and may be of therapeutic value in the setting of transplantation. PMID:19907413

  10. Chronic ethanol consumption results in deficient bone repair in rats.

    PubMed

    Chakkalakal, Dennis A; Novak, Jerzy R; Fritz, Edward D; Mollner, Teresa J; McVicker, Daniel L; Lybarger, Denise L; McGuire, Michael H; Donohue, Terrence M

    2002-01-01

    There is evidence that ethanol inhibits osteoblast function and that chronic ethanol consumption induces systemic bone loss and increases the risk of fracture in humans. The purpose of the present study was to determine whether chronic ethanol consumption also compromises the healing of injured bone. Male Sprague-Dawley rats, 8-10 weeks old, were placed into four feeding groups: group A received ethanol (36% of calories) as part of a liquid diet; group B was pair-fed to group A and received an isocaloric control diet containing maltodextrin; group C was fed the AIN-93M standard semi-purified liquid diet ad libitum; group D was fed the same ethanol diet as group A before bone injury, but after surgery (see below) these rats were given isocaloric control diet ad libitum. After 6 weeks on their respective diets, a bone repair model was surgically created at the midshaft in both fibulae of each rat. Seven weeks after injury the animals were euthanized and bone healing was evaluated by determining rigidity of the fibula by three-point bending, flexural modulus of the repair tissue and mineral content of the repair tissue. Rigidity of fibula in ethanol-fed rats and their pair-fed controls (groups A and B) were respectively 48 and 47% lower than in group C. Flexural modulus of the repair tissue in ethanol-fed rats had a 55% (P = 0.046) deficiency compared with their pair-fed controls. The mineral contents in groups A and B were respectively 16 and 13% lower than in group C. There were no significant differences in the results between groups C and D. Thus, the outcome of bone repair in ethanol-fed rats was deficient compared with rats receiving a standard maintenance diet. The repair tissue in ethanol-fed rats was mechanically inferior to that in pair-fed controls. This deficiency could not be attributed to the reduced food consumption of these animals. On the other hand, the restoration of normal bone healing in group D cannot be attributed solely to the cessation of

  11. Effect of alveolar pressure on pulmonary artery pressure in chronically hypoxic rats.

    PubMed

    Wach, R; Emery, C J; Bee, D; Barer, G R

    1987-02-01

    The effect on pulmonary artery pressure of a rise in alveolar pressure differed in chronically hypoxic rats (10% O2 for 3-5 weeks) compared with control rats. Chronically hypoxic rats have newly muscularised walls in arterioles in the alveolar region. Isolated lungs of chronically hypoxic and control rats were perfused with blood under conditions in which alveolar pressure was greater than left atrial pressure during both normoxia and hypoxia. Alveolar pressure was the effective downstream pressure. Pressure-flow lines were measured at low and high alveolar pressure (5 and 15 mmHg). During normoxia pressure-flow lines of chronically hypoxic rats had a steeper slope (higher resistance) and greater extrapolated intercept on the pressure axis (effective downstream pressure) than control rats. In both groups of rats the change from low to high alveolar pressure during normoxia caused an approximately parallel shift in the pressure-flow line similar to the change in alveolar pressure. During hypoxia, which led to an increase in slope and intercept in both groups of rats, the effect of a rise in alveolar pressure differed in chronically hypoxic from control rats. In control rats there was a small parallel shift in the pressure-flow line that was much less than the increase in alveolar pressure; in chronically hypoxic rats there was a large parallel shift in the pressure-flow line that was greater than the increase in alveolar pressure. Thus in chronically hypoxic rats hypoxic vasoconstriction probably occurred mainly in muscular alveolar vessels, whereas in control rats it probably occurred upstream in extra-alveolar vessels. At constant blood flow the relation between pulmonary artery pressure and alveolar pressure was measured while alveolar pressure was reduced from approximately 15 mmHg to zero during both normoxia and hypoxia. In control and chronically hypoxic rats the slope of this line was less than 1. At an alveolar pressure of 2-3 mmHg there was an inflection

  12. Sodium Hydrosulfide Relieves Neuropathic Pain in Chronic Constriction Injured Rats

    PubMed Central

    Lin, Jian-qing; Luo, Hui-qin; Lin, Cai-zhu; Chen, Jin-zhuan; Lin, Xian-zhong

    2014-01-01

    Aberrant neuronal activity in injured peripheral nerves is believed to be an important factor in the development of neuropathic pain (NPP). Channel protein pCREB of that activity has been shown to mitigate the onset of associated molecular events in the nervous system, and sodium hydrosulfide (NaHS) could inhibit the expression of pCREB. However, whether NaHS could relieve the pain, it needs further experimental research. Furthermore, the clinical potential that NaHS was used to relieve pain was limited so it would be required. To address these issues, the rats of sciatic nerve chronic constriction injury (CCI) were given intraperitoneal injection of NaHS containing hydrogen sulfide (H2S). The experimental results showed that NaHS inhibited the reduction of paw withdrawal thermal latency (PWTL), mechanical withdrawal threshold (MWT), and the level of pCREB in CCI rats in a dose-dependent manner and they were greatly decreased in NaHSM group (P < 0.05). NaHS alleviates chronic neuropathic pain by inhibiting expression of pCREB in the spinal cord of Sprague-Dawley rats. PMID:25506383

  13. Sodium hydrosulfide relieves neuropathic pain in chronic constriction injured rats.

    PubMed

    Lin, Jian-Qing; Luo, Hui-Qin; Lin, Cai-Zhu; Chen, Jin-Zhuan; Lin, Xian-Zhong

    2014-01-01

    Aberrant neuronal activity in injured peripheral nerves is believed to be an important factor in the development of neuropathic pain (NPP). Channel protein pCREB of that activity has been shown to mitigate the onset of associated molecular events in the nervous system, and sodium hydrosulfide (NaHS) could inhibit the expression of pCREB. However, whether NaHS could relieve the pain, it needs further experimental research. Furthermore, the clinical potential that NaHS was used to relieve pain was limited so it would be required. To address these issues, the rats of sciatic nerve chronic constriction injury (CCI) were given intraperitoneal injection of NaHS containing hydrogen sulfide (H2S). The experimental results showed that NaHS inhibited the reduction of paw withdrawal thermal latency (PWTL), mechanical withdrawal threshold (MWT), and the level of pCREB in CCI rats in a dose-dependent manner and they were greatly decreased in NaHSM group (P < 0.05). NaHS alleviates chronic neuropathic pain by inhibiting expression of pCREB in the spinal cord of Sprague-Dawley rats.

  14. Chronic cola drinking induces metabolic and cardiac alterations in rats

    PubMed Central

    Milei, José; Losada, Matilde Otero; Llambí, Hernán Gómez; Grana, Daniel R; Suárez, Daniel; Azzato, Francisco; Ambrosio, Giuseppe

    2011-01-01

    AIM: To investigate the effects of chronic drinking of cola beverages on metabolic and echocardiographic parameters in rats. METHODS: Forty-eight male Wistar rats were divided in 3 groups and allowed to drink regular cola (C), diet cola (L), or tap water (W) ad libitum during 6 mo. After this period, 50% of the animals in each group were euthanized. The remaining rats drank tap water ad libitum for an additional 6 mo and were then sacrificed. Rat weight, food, and beverage consumption were measured regularly. Biochemical, echocardiographic and systolic blood pressure data were obtained at baseline, and at 6 mo (treatment) and 12 mo (washout). A complete histopathology study was performed after sacrifice. RESULTS: After 6 mo, C rats had increased body weight (+7%, P < 0.01), increased liquid consumption (+69%, P < 0.001), and decreased food intake (-31%, P < 0.001). C rats showed mild hyperglycemia and hypertriglyceridemia. Normoglycemia (+69%, P < 0.01) and sustained hypertriglyceridemia (+69%, P < 0.01) were observed in C after washout. Both cola beverages induced an increase in left ventricular diastolic diameter (C: +9%, L: +7%, P < 0.05 vs W) and volumes (diastolic C: +26%, L: +22%, P < 0.01 vs W; systolic C: +24%, L: +24%, P < 0.05 vs W) and reduction of relative posterior wall thickness (C: -8%, L: -10%, P < 0.05 vs W). Cardiac output tended to increase (C: +25%, P < 0.05 vs W; L: +17%, not significant vs W). Heart rate was not affected. Pathology findings were scarce, related to aging rather than treatment. CONCLUSION: This experimental model may prove useful to investigate the consequences of high consumption of soft drinks. PMID:21526048

  15. Neuroprotective effect of escitalopram oxalate in rats with chronic hypoperfusion.

    PubMed

    Ma, Li; Lu, Zu-Neng; Hu, Pei; Yao, Chang-Jiang

    2015-08-01

    The neuroprotective effects of escitalopram oxalate in rats with chronic hypoperfusion and the possible mechanism were explored. Chronic hypoperfusion (2-VO) model was prepared and given escitalopram oxalate (experimental group) or PBS (control group) after 6 weeks. Eight weeks after the operation, Morris water maze test was carried out to evaluate the learning and memory ability of the rats. The cell proliferation, three-dimensional vascular distribution, cell morphological changes in ischemic area and the plasma vascular endothelial growth factor (VEGF) were detected to explore the possible mechanisms. (1) Morris water maze test showed that the escape latency in the experimental group was significantly shorter than in the control group, while the first quadrant swimming time in the experimental group was significantly longer than the control group (both P<0.01). (2) Cerebrovascular confocal detection results showed that the inside diameter of capillaries was significantly less in the experimental group than in the control group; the vascular density was significantly increased in the experimental group and the total area of capillaries was also significantly increased in the experimental group as compared with the control group. (3) There was statistically significant difference in BrdU-positive cells in the ischemic brain tissue between the experimental group and the control group (P=0.003<0.01). (4) VEGF concentrations in the plasma and the ischemic area were higher in the experimental group than in the control group (P<0.05). It was concluded that escitalopram oxalate could significantly improve the learning and memory ability of the rats with chronic cerebral ischemia probably by the VEGF-mediated angiogenesis. PMID:26223919

  16. Neuroprotective effect of escitalopram oxalate in rats with chronic hypoperfusion.

    PubMed

    Ma, Li; Lu, Zu-Neng; Hu, Pei; Yao, Chang-Jiang

    2015-08-01

    The neuroprotective effects of escitalopram oxalate in rats with chronic hypoperfusion and the possible mechanism were explored. Chronic hypoperfusion (2-VO) model was prepared and given escitalopram oxalate (experimental group) or PBS (control group) after 6 weeks. Eight weeks after the operation, Morris water maze test was carried out to evaluate the learning and memory ability of the rats. The cell proliferation, three-dimensional vascular distribution, cell morphological changes in ischemic area and the plasma vascular endothelial growth factor (VEGF) were detected to explore the possible mechanisms. (1) Morris water maze test showed that the escape latency in the experimental group was significantly shorter than in the control group, while the first quadrant swimming time in the experimental group was significantly longer than the control group (both P<0.01). (2) Cerebrovascular confocal detection results showed that the inside diameter of capillaries was significantly less in the experimental group than in the control group; the vascular density was significantly increased in the experimental group and the total area of capillaries was also significantly increased in the experimental group as compared with the control group. (3) There was statistically significant difference in BrdU-positive cells in the ischemic brain tissue between the experimental group and the control group (P=0.003<0.01). (4) VEGF concentrations in the plasma and the ischemic area were higher in the experimental group than in the control group (P<0.05). It was concluded that escitalopram oxalate could significantly improve the learning and memory ability of the rats with chronic cerebral ischemia probably by the VEGF-mediated angiogenesis.

  17. Chronic administration of isocarbophos induces vascular cognitive impairment in rats.

    PubMed

    Li, Peng; Yin, Ya-Ling; Zhu, Mo-Li; Pan, Guo-Pin; Zhao, Fan-Rong; Lu, Jun-Xiu; Liu, Zhan; Wang, Shuang-Xi; Hu, Chang-Ping

    2016-04-01

    Vascular dementia, being the most severe form of vascular cognitive impairment (VCI), is caused by cerebrovascular disease. Whether organophosphorus causes VCI remains unknown. Isocarbophos (0.5 mg/kg per 2 days) was intragastrically administrated to rats for 16 weeks. The structure and function of cerebral arteries were assayed. The learning and memory were evaluated by serial tests of step-down, step-through and morris water maze. Long-term administration of isocarbophos reduced the hippocampal acetylcholinesterase (AChE) activity and acetylcholine (ACh) content but did not alter the plasma AChE activity, and significantly damaged the functions of learning and memory. Moreover, isocarbophos remarkably induced endothelial dysfunction in the middle cerebral artery and the expressions of ICAM-1 and VCAM-1 in the posterior cerebral artery. Morphological analysis by light microscopy and electron microscopy indicated disruptions of the hippocampus and vascular wall in the cerebral arteries from isocarbophos-treated rats. Treatment of isocarbophos injured primary neuronal and astroglial cells isolated from rats. Correlation analysis demonstrated that there was a high correlation between vascular function of cerebral artery and hippocampal AChE activity or ACh content in rats. In conclusion, chronic administration of isocarbophos induces impairments of memory and learning, which is possibly related to cerebral vascular dysfunction. PMID:26818681

  18. Chronic Kidney Disease Impairs Bone Defect Healing in Rats

    PubMed Central

    Liu, Weiqing; Kang, Ning; Seriwatanachai, Dutmanee; Dong, Yuliang; Zhou, Liyan; Lin, Yunfeng; Ye, Ling; Liang, Xing; Yuan, Quan

    2016-01-01

    Chronic kidney disease (CKD) has been regarded as a risk for bone health. The aim of this study was to evaluate the effect of CKD on bone defect repair in rats. Uremia was induced by subtotal renal ablation, and serum levels of BUN and PTH were significantly elevated four weeks after the second renal surgery. Calvarial defects of 5-mm diameter were created and implanted with or without deproteinized bovine bone mineral (DBBM). Micro-CT and histological analyses consistently revealed a decreased newly regenerated bone volume for CKD rats after 4 and 8 weeks. In addition, 1.4-mm-diameter cortical bone defects were established in the distal end of femora and filled with gelatin sponge. CKD rats exhibited significantly lower values of regenerated bone and bone mineral density (BMD) within the cortical gap after 2 and 4 weeks. Moreover, histomorphometric analysis showed an increase in both osteoblast number (N.Ob/B.Pm) and osteoclast number (N.Oc/B.Pm) in CKD groups due to hyperparathyroidism. Notably, collagen maturation was delayed in CKD rats as verified by Masson’s Trichrome staining. These data indicate that declined renal function negatively affects bone regeneration in both calvarial and femoral defects. PMID:26955758

  19. Effect of chronic centrifugation on body composition in the rat.

    NASA Technical Reports Server (NTRS)

    Pitts, G. C.; Bull, L. S.; Oyama, J.

    1972-01-01

    Two groups of adult female rats were chronically centrifuged for 60 days (2.76 G, 4.15 G, controls at 1.00 G). Live weights of centrifugal rats decreased about 20 g (6%) per Delta 1 G above control. This weight loss comprised reductions in both body fat and fat-free body weight (FFBW) as determined by body-composition studies on eight rats per group killed at the end of centrifugation. Of nine components constituting the FFBW, only skeletal muscle, liver, and heart changed significantly in weight. Chemical composition showed reductions (compared with controls) in the fat fraction of most components and increases in the water fraction of liver and gut. Identical measurements were made on the remaining eight rats per group killed 43 days after return to 1 G. Neither centrifuged group had reached the control body-weight level at this time. No statistically significant effect of previous G level was found in any of the body-composition parameters. The possible involvment of physiological regulation was considered.

  20. Hemodynamic alterations in chronically conscious unrestrained diabetic rats

    SciTech Connect

    Carbonell, L.F.; Salmon, M.G.; Garcia-Estan, J.; Salazar, F.J.; Ubeda, M.; Quesada, T.

    1987-05-01

    Important cardiovascular dysfunctions have been described in streptozotocin (STZ)-diabetic rats. To determine the influence of these changes on the hemodynamic state and whether insulin treatment can avoid them, different hemodynamic parameters, obtained by the thermodilution method, were studied in STZ-induced (65 mg/kg) diabetic male Wistar rats, as well as in age-control, weight-control, and insulin-treated diabetic ones. Plasma volume was measured by dilution of radioiodinated (/sup 125/I) human serum albumin. All rats were examined in the conscious, unrestrained state 12 wk after induction of diabetes or acidified saline (pH 4.5) injection. At 12 wk of diabetic state most important findings were normotension, high blood volume, bradycardia, increase in stroke volume, cardiac output, and cardiosomatic ratio, and decrease in total peripheral resistance and cardiac contractility and relaxation (dP/dt/sub max/ and dP/dt/sub min/ of left ventricular pressure curves). The insulin-treated diabetic rats did not show any hemodynamic differences when compared with the control animals. These results suggest that important hemodynamic alterations are present in the chronic diabetic states, possibly conditioning congestive heart failure. These alterations can be prevented by insulin treatment.

  1. Chronic Kidney Disease Impairs Bone Defect Healing in Rats.

    PubMed

    Liu, Weiqing; Kang, Ning; Seriwatanachai, Dutmanee; Dong, Yuliang; Zhou, Liyan; Lin, Yunfeng; Ye, Ling; Liang, Xing; Yuan, Quan

    2016-03-09

    Chronic kidney disease (CKD) has been regarded as a risk for bone health. The aim of this study was to evaluate the effect of CKD on bone defect repair in rats. Uremia was induced by subtotal renal ablation, and serum levels of BUN and PTH were significantly elevated four weeks after the second renal surgery. Calvarial defects of 5-mm diameter were created and implanted with or without deproteinized bovine bone mineral (DBBM). Micro-CT and histological analyses consistently revealed a decreased newly regenerated bone volume for CKD rats after 4 and 8 weeks. In addition, 1.4-mm-diameter cortical bone defects were established in the distal end of femora and filled with gelatin sponge. CKD rats exhibited significantly lower values of regenerated bone and bone mineral density (BMD) within the cortical gap after 2 and 4 weeks. Moreover, histomorphometric analysis showed an increase in both osteoblast number (N.Ob/B.Pm) and osteoclast number (N.Oc/B.Pm) in CKD groups due to hyperparathyroidism. Notably, collagen maturation was delayed in CKD rats as verified by Masson's Trichrome staining. These data indicate that declined renal function negatively affects bone regeneration in both calvarial and femoral defects.

  2. Effects of acute and chronic administration of methylprednisolone on oxidative stress in rat lungs* **

    PubMed Central

    Torres, Ronaldo Lopes; Torres, Iraci Lucena da Silva; Laste, Gabriela; Ferreira, Maria Beatriz Cardoso; Cardoso, Paulo Francisco Guerreiro; Belló-Klein, Adriane

    2014-01-01

    Objective: To determine the effects of acute and chronic administration of methylprednisolone on oxidative stress, as quantified by measuring lipid peroxidation (LPO) and total reactive antioxidant potential (TRAP), in rat lungs. Methods: Forty Wistar rats were divided into four groups: acute treatment, comprising rats receiving a single injection of methylprednisolone (50 mg/kg i.p.); acute control, comprising rats i.p. injected with saline; chronic treatment, comprising rats receiving methylprednisolone in drinking water (6 mg/kg per day for 30 days); and chronic control, comprising rats receiving normal drinking water. Results: The levels of TRAP were significantly higher in the acute treatment group rats than in the acute control rats, suggesting an improvement in the pulmonary defenses of the former. The levels of lung LPO were significantly higher in the chronic treatment group rats than in the chronic control rats, indicating oxidative damage in the lung tissue of the former. Conclusions: Our results suggest that the acute use of corticosteroids is beneficial to lung tissue, whereas their chronic use is not. The chronic use of methylprednisolone appears to increase lung LPO levels. PMID:25029646

  3. Chronic Stress Decreases Cerebrovascular Responses During Rat Hindlimb Electrical Stimulation

    PubMed Central

    Lee, Sohee; Kang, Bok-Man; Shin, Min-Kyoo; Min, Jiwoong; Heo, Chaejeong; Lee, Yubu; Baeg, Eunha; Suh, Minah

    2015-01-01

    Repeated stress is one of the major risk factors for cerebrovascular disease, including stroke, and vascular dementia. However, the functional alterations in the cerebral hemodynamic response induced by chronic stress have not been clarified. Here, we investigated the in vivo cerebral hemodynamic changes and accompanying cellular and molecular changes in chronically stressed rats. After 3 weeks of restraint stress, the elicitation of stress was verified by behavioral despair in the forced swimming test and by physical indicators of stress. The evoked changes in the cerebral blood volume and pial artery responses following hindpaw electrical stimulation were measured using optical intrinsic signal imaging. We observed that, compared to the control group, animals under chronic restraint stress exhibited a decreased hemodynamic response, with a smaller pial arterial dilation in the somatosensory cortex during hindpaw electrical stimulation. The effect of chronic restraint stress on vasomodulator enzymes, including neuronal nitric oxide synthase (nNOS) and heme oxygenase-2 (HO-2), was assessed in the somatosensory cortex. Chronic restraint stress downregulated nNOS and HO-2 compared to the control group. In addition, we examined the subtypes of cells that can explain the environmental changes due to the decreased vasomodulators. The expression of parvalbumin in GABAergic interneurons and glutamate receptor-1 in neurons were decreased, whereas the microglial activation was increased. Our results suggest that the chronic stress-induced alterations in cerebral vascular function and the modulations of the cellular expression in the neuro-vasomodulatory system may be crucial contributing factors in the development of various vascular-induced conditions in the brain. PMID:26778944

  4. Bone disease in uremic patients: advances in PTH suppression.

    PubMed

    Brancaccio, Diego; Cozzolino, Mario; Gorio, Alfredo; Di Giulio, Anna Maria; Gallieni, Maurizio

    2002-01-01

    Chronic renal failure is often complicated by altered calcium and phosphate omeostasis. Many patients develop secondary hyperparathyroidism during the course of the disease. Therefore, both prevention and treatment of secondary hyperparathyroidism are central issues in the treatment of uremic patients. Active vitamin D metabolites are important agents in uremic patients, who have a defective activity of the renal 1alpha-hydroxylase responsible for calcitriol synthesis. Howewer, treatment with calcitriol has some limitations, namely an increase in intestinal phosphate absorption, a possible calcium overload and therefore an increase in CaxP ion product. These limitations stimulated an active research on the development of vitamin D analogs with reduced effects on intestinal transport as well as on bone mobilization of calcium and phosphate. Three vitamin D analogs, which have been used in humans, are reviewed in this article: 22-oxacalcitriol (Maxacalcitol), 19-nor-1alpha,25(OH)2 vitamin D2 (Paricalcitol), and 1alpha(OH) Vitamin D2 (Doxercalciferol). In addition, a new pharmacologic approach to the treatment of secondary hyperparathyroidism has been developed: the use of agonists for the parathyroid calcium sensing receptor, or calcimimetics. AMG O73, a second generation agent, is now under clinical evaluation in phase 3 studies, and it will soon be available in clinical practice. Given the different mechanism of action, it will be possible to use it along with vitamin D analogs and non calcemic phosphate binders. A broader spectrum of therapeutic approaches will enable the nephrologist to individually tailor the treatment of secondary hyperparathyroidism. PMID:12515379

  5. Gender differences in the development of uremic cardiomyopathy following partial nephrectomy: Role of progesterone.

    PubMed

    Drummond, Christopher A; Buddny, George; Haller, Steven T; Liu, Jiang; Yan, Yanling; Xie, Zijian; Malhotra, Deepak; Shapiro, Joseph I; Tian, Jiang

    2013-01-31

    Gender difference has been suggested as a risk factor for developing cardiovascular and renal diseases in humans and experimental animals. As a major sex hormone, progesterone was reported to compete with cardiotonic steroid binding to Na/K-ATPase. Our previous publication demonstrated that cardiotonic steroids (e.g., marinobufagenin) play an important role in the development of experimental uremic cardiomyopathy. We also observed that the putative mineralocorticoid antagonists, spironolactone and its major metabolite canrenone, antagonize binding of cardiotonic steroids to Na/K-ATPase in a competitive manner and also ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy. In the following studies, we noted that progesterone displayed competitive inhibition of cardiotonic steroid binding to Na/K-ATPase and partially inhibited collagen synthesis induced by marinobufagenin in cultured cardiac fibroblasts. Therefore, we sought to examine whether female rats displayed less uremic cardiomyopathy than male rats when subjected to partial nephrectomy. Although partial nephrectomy caused the induction of smaller increases in blood pressure of female rats, they appeared to be similarly susceptible to cardiac remodeling induced by partial nephrectomy in terms of hypertrophy and fibrosis as age-matched male rats. The possible explanations for our findings are therefore discussed. PMID:24404431

  6. Gender differences in the development of uremic cardiomyopathy following partial nephrectomy: Role of progesterone

    PubMed Central

    Drummond, Christopher A; Buddny, George; Haller, Steven T; Liu, Jiang; Yan, Yanling; Xie, Zijian; Malhotra, Deepak; Shapiro, Joseph I; Tian, Jiang

    2013-01-01

    Gender difference has been suggested as a risk factor for developing cardiovascular and renal diseases in humans and experimental animals. As a major sex hormone, progesterone was reported to compete with cardiotonic steroid binding to Na/K-ATPase. Our previous publication demonstrated that cardiotonic steroids (e.g., marinobufagenin) play an important role in the development of experimental uremic cardiomyopathy. We also observed that the putative mineralocorticoid antagonists, spironolactone and its major metabolite canrenone, antagonize binding of cardiotonic steroids to Na/K-ATPase in a competitive manner and also ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy. In the following studies, we noted that progesterone displayed competitive inhibition of cardiotonic steroid binding to Na/K-ATPase and partially inhibited collagen synthesis induced by marinobufagenin in cultured cardiac fibroblasts. Therefore, we sought to examine whether female rats displayed less uremic cardiomyopathy than male rats when subjected to partial nephrectomy. Although partial nephrectomy caused the induction of smaller increases in blood pressure of female rats, they appeared to be similarly susceptible to cardiac remodeling induced by partial nephrectomy in terms of hypertrophy and fibrosis as age-matched male rats. The possible explanations for our findings are therefore discussed. PMID:24404431

  7. Bone metabolism of male rats chronically exposed to cadmium.

    PubMed

    Brzóska, Malgorzata M; Moniuszko-Jakoniuk, Janina

    2005-09-15

    Recently, based on a female rat model of human exposure, we have reported that low-level chronic exposure to cadmium (Cd) has an injurious effect on the skeleton. The purpose of the current study was to investigate whether the exposure may also affect bone metabolism in a male rat model and to estimate the gender-related differences in the bone effect of Cd. Young male Wistar rats received drinking water containing 0, 1, 5, or 50 mg Cd/l for 12 months. The bone effect of Cd was evaluated using bone densitometry and biochemical markers of bone turnover. Renal handling of calcium (Ca) and phosphate, and serum concentrations of vitamin D metabolites, calcitonin, and parathormone were estimated as well. At treatment with 1 mg Cd/l, corresponding to the low environmental exposure in non-Cd-polluted areas, the bone mineral content (BMC) and density (BMD) at the femur and lumbar spine (L1-L5) and the total skeleton BMD did not differ compared to control. However, from the 6th month of the exposure, the Z score BMD indicated osteopenia in some animals and after 12 months the bone resorption very clearly tended to an increase. The rats' exposure corresponding to human moderate (5 mg Cd/l) and especially relatively high (50 mg Cd/l) exposure dose- and duration-dependently disturbed the processes of bone turnover and bone mass accumulation leading to formation of less dense than normal bone tissue. The effects were accompanied by changes in the serum concentration of calciotropic hormones and disorders in Ca and phosphate metabolism. It can be concluded that low environmental exposure to Cd may be only a subtle risk factor for skeletal demineralization in men. The results together with our previous findings based on an analogous model using female rats give clear evidence that males are less vulnerable to the bone effects of Cd compared to females.

  8. Influence of imipramine on the duration of immobility in chronic forced-swim-stressed rats.

    PubMed

    Kitamura, Yoshihisa; Araki, Hiroaki; Nagatani, Tadashi; Takao, Katsuyuki; Shibata, Kazuhiko; Gomita, Yutaka

    2004-12-01

    We studied the influence of imipramine on the duration of immobility in chronic forced-swim-stressed rats. Both single and chronic administration of imipramine potently shortened immobility in naive rats during forced-swim testing. However, chronic, 14-day forced-swim stress testing blocked the immobility-decreasing effect induced by a single administration of imipramine. When imipramine was administered for 14 days concurrently with forced-swim stress testing, immobility was shortened significantly. From the viewpoint of imipramine's effect, these findings suggest that chronic forced-swim stress testing in rats may be an effective animal model for depression.

  9. Chronic kidney disease aggravates arteriovenous fistula damage in rats.

    PubMed

    Langer, Stephan; Kokozidou, Maria; Heiss, Christian; Kranz, Jennifer; Kessler, Tina; Paulus, Niklas; Krüger, Thilo; Jacobs, Michael J; Lente, Christina; Koeppel, Thomas A

    2010-12-01

    Neointimal hyperplasia (NIH) and impaired dilatation are important contributors to arteriovenous fistula (AVF) failure. It is unclear whether chronic kidney disease (CKD) itself causes adverse remodeling in arterialized veins. Here we determined if CKD specifically triggers adverse effects on vascular remodeling and assessed whether these changes affect the function of AVFs. For this purpose, we used rats on a normal diet or on an adenine-rich diet to induce CKD and created a fistula between the right femoral artery and vein. Fistula maturation was followed noninvasively by high-resolution ultrasound (US), and groups of rats were killed on 42 and 84 days after surgery for histological and immunohistochemical analyses of the AVFs and contralateral femoral vessels. In vivo US and ex vivo morphometric analyses confirmed a significant increase in NIH in the AVFs of both groups with CKD compared to those receiving a normal diet. Furthermore, we found using histological evaluation of the fistula veins in the rats with CKD that the media shrank and their calcification increased significantly. Afferent artery dilatation was significantly impaired in CKD and the downstream fistula vein had delayed dilation after surgery. These changes were accompanied by significantly increased peak systolic velocity at the site of the anastomosis, implying stenosis. Thus, CKD triggers adverse effects on vascular remodeling in AVFs, all of which contribute to anatomical and/or functional stenosis.

  10. Water balance in rats exposed to chronic centrifugation.

    PubMed

    Ortiz, R M; Wade, C E

    2000-07-01

    Changes in gravitational load have been shown to alter renal function, which could potentially affect water balance. Therefore, the present study was conducted to determine the effects of chronic centrifugation on water balance. Eight Sprague-Dawley rats were centrifuged (12 days at 2 G), and eight rats were used as a control group. Water balance over the course of the study was determined by quantifying the percentage (%) of total body water [TBW; (TBW/body mass)] and water flux (water consumption - urine volume). TBW was estimated, by means of deuterium oxide dilution, before the study and after 3 days of centrifugation and by means of desiccation after 12 days of centrifugation. %TBW did not change in the centrifuged rats from initial levels or relative to controls over the course of the study. Differences between the sum of water consumption and sum of urine volume for the 12-day period were the same in both groups. Although an initial period of negative water balance was observed, the lack of a change in %TBW among the three measurement periods or in water flux over the 12 days of centrifugation suggests that water balance is not negatively affected as a result of centrifugation at 2 G.

  11. Separation of uremic toxins from urine with resorcinarene-based ion chromatography columns.

    PubMed

    Panahi, Tayyebeh; Weaver, Douglas J; Lamb, John D; Harrison, Roger G

    2015-01-01

    People with chronic kidney disease suffer from uremic toxins which accumulate in their bodies. Detection and quantification of uremic toxins help diagnose kidney problems and start patient care. The aim of this research was to seek a new method to assist this diagnosis by trace level detection and separation of guanidine containing uremic toxins in water and urine. To detect and quantify the uremic toxins, new stationary phases for ion chromatography (IC) columns based on glutamic acid functionalized resorcinarenes bound to divinylbenzene macroporous resin were prepared. The new column packing material afforded separation of the five compounds: guanidinoacetic acid, guanidine, methylguanidine, creatinine, and guanidinobenzoic acid in 30min. Peak resolutions ranged from 7.6 to 1.3. Gradient elutions at ambient temperature with methanesulfonic acid (MSA) solution as eluent resulted in detection levels in water from 10 to 47ppb and in synthetic urine from 28 to 180ppb. Limits of quantification for the analytes using pulsed amperometric detection were 30-160ppb in water and 93-590ppb in urine. Trace levels of creatinine (1ppm) were detected in the urine of a healthy individual using the columns.

  12. Escherichia coli O 157:H7-associated hemolytic-uremic syndrome after ingestion of contaminated hamburgers.

    PubMed

    Brandt, J R; Fouser, L S; Watkins, S L; Zelikovic, I; Tarr, P I; Nazar-Stewart, V; Avner, E D

    1994-10-01

    We conducted a retrospective analysis of 37 children with Escherichia coli O157:H7-associated hemolytic-uremic syndrome. The infection was traced to contaminated hamburgers at a fast-food restaurant chain. Within 5 days of the first confirmed case, the Washington State Department of Health identified the source and interrupted transmission of infection. Ninety-five percent of the children initially had severe hemorrhagic colitis. Nineteen patients (51%) had significant extrarenal abnormalities, including pancreatitis, colonic necrosis, glucose intolerance, coma, stroke, seizures, myocardial dysfunction, pericardial effusions, adult respiratory disease syndrome, and pleural effusions. Three deaths occurred, each in children with severe multisystem disease. At follow-up two children have significant impairment of renal function (glomerular filtration rate < 80 ml/min/per 1.73 Hm2); both of these children have a normal serum creatinine concentration. Hemolytic-uremic syndrome is the most common cause of acute renal failure in children, and this experience emphasizes the systemic nature of this disease. Clinicians should anticipate that multisystem involvement may occur in these patients, necessitating acute intervention or chronic follow-up. This outbreak of Hemolytic-uremic syndrome also highlights the microbiologic hazards of inadequately prepared food and emphasizes the importance of public health intervention in controlling Hemolytic-uremic syndrome.

  13. Deficiency of Soluble α-Klotho as an Independent Cause of Uremic Cardiomyopathy.

    PubMed

    Xie, J; Wu, Y-L; Huang, C-L

    2016-01-01

    Cardiovascular disease (CVD) is the major cause of mortality for patients with chronic kidney disease (CKD). Cardiac hypertrophy, occurring in up to 95% patients with CKD (also known as uremic cardiomyopathy), increases their risk for cardiovascular death. Many CKD-specific risk factors of uremic cardiomyopathy have been recognized, such as secondary hyperparathyroidism, indoxyl sulfate (IS)/p-cresyl, and vitamin D deficiency. However, several randomized controlled trials have recently shown that these risk factors have little impact on the mortality of CVD. Klotho is a type 1 membrane protein predominantly produced in the kidney, and CKD is known to be a Klotho-deficient state. Because of its important role in FGF23 and phosphate metabolism, Klotho is believed to affect cardiac growth and function indirectly through FGF23 and phosphate. Recent studies showed that soluble Klotho protects the heart against stress-induced cardiac hypertrophy by inhibiting TRPC6 channel-mediated abnormal Ca(2+) signaling in the heart, and the decreased level of circulating soluble Klotho in CKD is an important cause of uremic cardiomyopathy independent of FGF23 and phosphate. These new evidence suggested that Klotho is an independent contributing factor for uremic cardiomyopathy and a possible new target for treatment of this disease. PMID:27125747

  14. Cerebro-renal interactions: impact of uremic toxins on cognitive function.

    PubMed

    Watanabe, Kimio; Watanabe, Tsuyoshi; Nakayama, Masaaki

    2014-09-01

    Cognitive impairment (CI) associated with chronic kidney disease (CKD) has received attention as an important problem in recent years. Causes of CI with CKD are multifactorial, and include cerebrovascular disease, renal anemia, secondary hyperparathyroidism, dialysis disequilibrium, and uremic toxins (UTs). Among these causes, little is known about the role of UTs. We therefore selected 21 uremic compounds, and summarized reports of cerebro-renal interactions associated with UTs. Among the compounds, uric acid, indoxyl sulfate, p-cresyl sulfate, interleukin 1-β, interleukin 6, TNF-α, and PTH were most likely to affect the cerebro-renal interaction dysfunction; however, sufficient data have not been obtained for other UTs. Notably, most of the data were not obtained under uremic conditions; therefore, the impact and mechanism of each UT on cognition and central nervous system in uremic state remains unknown. At present, impacts and mechanisms of UT effects on cognition are poorly understood. Clarifying the mechanisms and establishing novel therapeutic strategies for cerebro-renal interaction dysfunction is expected to be subject of future research.

  15. Energy expenditures & physical activity in rats with chronic suboptimal nutrition

    PubMed Central

    Rising, Russell; Lifshitz, Fima

    2006-01-01

    Background Sub-optimally nourished rats show reduced growth, biochemical and physiological changes. However, no one has assessed metabolic rate adaptations in rats subjected to chronic suboptimal nutrition (CSN). In this study energy expenditure (EE; kcal/100 g body weight) and physical activity (PA; oscillations in weight/min/kg body weight) were assessed in rats subjected to three levels of CSN. Results Body weight gain was diminished (76.7 ± 12.0 and 61.6 ± 11.0 g) in rats fed 70 and 60% of the ad-libitum fed controls which gained more weight (148.5 ± 32.3 g). The rats fed 80% gained weight similarly to controls (136.3 ± 10.5 g). Percent Fat-free body mass was reduced (143.8 ± 8.7 and 142.0 ± 7.6 g) in rats fed 70 and 60% of ad-libitum, but not in those fed 80% (200.8 ± 17.5 g) as compared with controls (201.6 ± 33.4 g). Body fat (g) decreased in rats fed 80% (19.7 ± 5.3), 70% (15.3 ± 3.5) and 60% (9.6 ± 2.7) of ad-libitum in comparison to controls (26.0 ± 6.7). EE and PA were also altered by CSN. The control rats increased their EE and PA during the dark periods by 1.4 ± 0.8 and 1.7 ± 1.1 respectively, as compared with light the period; whereas CSN rats fed 80 and 70% of ad-libitum energy intake had reduced EE and PA during the dark periods as compared with the light period EE(7.5 ± 1.4 and 7.8 ± 0.6 vs. 9.0 ± 1.2 and 9.7 ± 0.8; p < 0.05, respectively), PA(3.1 ± 0.8 and 1.6 ± 0.4 vs. 4.1 ± 0.9 and 2.4 ± 0.4; p < 0.05) and RQ (0.87 ± 0.04 and 0.85 ± 0.5; vs. 0.95 ± 0.03 and 0.91 ± 0.05 p < 0.05). In contrast, both light (7.1 ± 1.4) and dark period (6.2 ± 1.0) EE and PA (3.4 ± 0.9 and 2.5 ± 0.5 respectively) were reduced in rats fed 60% of ad-libitum energy intake. Conclusion CSN rats adapt to mild energy restriction by reducing body fat, EE and PA mainly during the dark period while growth proceeds and lean body mass is preserved. At higher levels of energy restrictions there is decreased growth, body fat and lean mass. Moreover EE

  16. Pharmacological attenuation of chronic alcoholic pancreatitis induced hypersensitivity in rats

    PubMed Central

    McIlwrath, Sabrina L; Westlund, Karin N

    2015-01-01

    AIM: To characterize an alcohol and high fat diet induced chronic pancreatitis rat model that mimics poor human dietary choices. METHODS: Experimental rats were fed a modified Lieber-DeCarli alcohol (6%) and high-fat (65%) diet (AHF) for 10 wk while control animals received a regular rodent chow diet. Weekly behavioral tests determined mechanical and heat sensitivity. In week 10 a fasting glucose tolerance test was performed, measuring blood glucose levels before and after a 2 g/kg bodyweight intraperitoneal (i.p.) injection of glucose. Post mortem histological analysis was performed by staining pancreas and liver tissue sections with hematoxylin and eosin. Pancreas sections were also stained with Sirius red and fast green to quantify collagen content. Insulin-expressing cells were identified immunohistochemically in separate sections. Tissue staining density was quantified using Image J software. After mechanical and heat sensitivity became stable (weeks 6-10) in the AHF-fed animals, three different drugs were tested for their efficacy in attenuating pancreatitis associated hypersensitivity: a Group II metabotropic glutamate receptor specific agonist (2R,4R)-4-Aminopyrrolidine-2,4-dicarboxylate (APDC, 3 mg/kg, ip; Tocris, Bristol, United Kingdom), nociceptin (20, 60, 200 nmol/kg, ip; Tocris), and morphine sulfate (3 mg/kg, μ-opioid receptor agonist; Baxter Healthcare, Deerfield, IL, United States). RESULTS: Histological analysis of pancreas and liver determined that unlike control rats, AHF fed animals had pancreatic fibrosis, acinar and beta cell atrophy, with steatosis in both organs. Fat vacuolization was significantly increased in AHF fed rats (6.4% ± 1.1% in controls vs 23.8% ± 4.2%, P < 0.05). Rats fed the AHF diet had reduced fasting glucose tolerance in week 10 when peak blood glucose levels reached significantly higher concentrations than controls (127.4 ± 9.2 mg/dL in controls vs 161.0 ± 8.6 mg/dL, P < 0.05). This concurred with a 3.5 fold higher

  17. Chronic toxicity study of cyclohexanone in rats and mice.

    PubMed

    Lijinsky, W; Kovatch, R M

    1986-10-01

    A 2-year chronic toxicity assay of cyclohexanone (CAS: 108-94-1) was conducted in F344 rats and (C57BL/6 X C3H)F1 mice by administering a solution of cyclohexanone in drinking water. Two concentrations were given to rats, 6,500 and 3,300 ppm (wt/vol). Male mice received 13,000 and 6,500 ppm, while female mice were given three concentrations, 25,000, 13,000, and 6,500 ppm. Each treatment group consisted of 50 or 52 male and 50 or 52 female rats or mice, except 47 male mice treated with the highest dose and 41 female mice treated with the highest dose, and there was a group of untreated controls of each species. Survival and weight gain were similar to those of controls at the lowest cyclohexanone dose in both sexes of both species, but weight gain was depressed at all of the higher doses. Survival was good (greater than 80% at 90 wk) in all groups except in female mice at the 2 highest doses; at 25,000 ppm of cyclohexanone, only 50% of mice lived beyond 1 year. Most of the neoplasms in the treated groups did not differ significantly in number from those in the controls. Male rats receiving 3,300 ppm cyclohexanone had a 13% incidence of adrenal cortex adenomas (7 animals) compared with an incidence of 2% in controls; the incidence of this neoplasm did not increase in the male rats receiving 6,500 ppm or in the female rats given either dose. The mice had a statistically significant increase in incidence of lymphomas-leukemias among the females given 6,500 ppm, but not among the groups given higher doses of cyclohexanone. Male mice given 6,500 ppm cyclohexanone showed an increased incidence of hepatocellular adenomas and carcinomas, 50% versus 32.5% in controls, but the incidence of these neoplasms was only 37% in the male mice given 13,000 ppm cyclohexanone. The incidence of lymphomas in male mice and of hepatocellular neoplasms in female mice given cyclohexanone did not differ from that in the controls. The evidence for carcinogenic activity of cyclohexanone is

  18. Hemolytic uremic syndrome: pathogenesis and update of interventions.

    PubMed

    Palermo, Marina S; Exeni, Ramón A; Fernández, Gabriela C

    2009-08-01

    The typical form of hemolytic uremic syndrome (HUS) is the major complication of Shiga toxin-producing Escherichia coli infections. HUS is a critical health problem in Argentina since it is the main cause of acute renal failure in children and the second cause of chronic renal failure, accounting for 20% of renal transplants in children and adolescents in Argentina. Despite extensive research in the field, the mainstay of treatment for patients with HUS is supportive therapy, and there are no specific therapies preventing or ameliorating the disease course. In this review, we present the current knowledge about pathogenic mechanisms and discuss traditional and innovative therapeutic approaches, with special focus in Argentinean contribution. The hope that a better understanding of transmission dynamics and pathogenesis of this disease will produce better therapies to prevent the acute mortality and the long-term morbidity of HUS is the driving force for intensified research.

  19. Reversible visual evoked potential abnormalities in uremic children.

    PubMed

    Ethier, Audrey-Anne; Lippé, Sarah; Mérouani, Aicha; Lassonde, Maryse; Saint-Amour, Dave

    2012-06-01

    In this case study, two cystinosis-related uremic children were followed at the Department of Nephrology, University of Montreal Hospital Center Sainte-Justine. Pattern-reversal visual evoked potentials were recorded at two time points, during dialysis treatment (time 1) and after renal transplant (time 2). Data were compared with those obtained from a control group (n = 6). The P1 component was selected and analyzed as the electrophysiologic marker of interest. At time 1, P1 latency was delayed, and P1 amplitude was reduced compared with control subjects. Both responses fell within normal range after kidney transplantation. These results indicate that renal failure and dialysis are associated with abnormal visual evoked potentials in children with chronic renal failure, but such alterations of visual processing are reversible after kidney transplant. PMID:22633636

  20. Speckle tracking echocardiography detects uremic cardiomyopathy early and predicts cardiovascular mortality in ESRD.

    PubMed

    Kramann, Rafael; Erpenbeck, Johanna; Schneider, Rebekka K; Röhl, Anna B; Hein, Marc; Brandenburg, Vincent M; van Diepen, Merel; Dekker, Friedo; Marx, Nicolaus; Floege, Jürgen; Becker, Michael; Schlieper, Georg

    2014-10-01

    Cardiovascular mortality is high in ESRD, partly driven by sudden cardiac death and recurrent heart failure due to uremic cardiomyopathy. We investigated whether speckle-tracking echocardiography is superior to routine echocardiography in early detection of uremic cardiomyopathy in animal models and whether it predicts cardiovascular mortality in patients undergoing dialysis. Using speckle-tracking echocardiography in two rat models of uremic cardiomyopathy soon (4-6 weeks) after induction of kidney disease, we observed that global radial and circumferential strain parameters decreased significantly in both models compared with controls, whereas standard echocardiographic readouts, including fractional shortening and cardiac output, remained unchanged. Furthermore, strain parameters showed better correlations with histologic hallmarks of uremic cardiomyopathy. We then assessed echocardiographic and clinical characteristics in 171 dialysis patients. During the 2.5-year follow-up period, ejection fraction and various strain parameters were significant risk factors for cardiovascular mortality (primary end point) in a multivariate Cox model (ejection fraction hazard ratio [HR], 0.97 [95% confidence interval (95% CI), 0.95 to 0.99; P=0.012]; peak global longitudinal strain HR, 1.17 [95% CI, 1.07 to 1.28; P<0.001]; peak systolic and late diastolic longitudinal strain rates HRs, 4.7 [95% CI, 1.23 to 17.64; P=0.023] and 0.25 [95% CI, 0.08 to 0.79; P=0.02], respectively). Multivariate Cox regression analysis revealed circumferential early diastolic strain rate, among others, as an independent risk factor for all-cause mortality (secondary end point; HR, 0.43; 95% CI, 0.25 to 0.74; P=0.002). Together, these data support speckle tracking as a postprocessing echocardiographic technique to detect uremic cardiomyopathy and predict cardiovascular mortality in ESRD.

  1. Ciproxifan differentially modifies cognitive impairment evoked by chronic stress and chronic corticosterone administration in rats.

    PubMed

    Trofimiuk, Emil; Braszko, Jan J

    2015-04-15

    Despite the development of neuroscience and spectacular discoveries, the clear functions and the role of histamine are still not fully understood, especially in the context of the negative impact of prolonged stress exposure on the cognition. The purpose of this study was to evaluate the participation of hypercortisolemia in the detrimental effect of stress on cognitive function and their preclusion by affecting the histaminergic system with ciproxifan. Specifically, we attempted to characterize the preventive action of a single dose of ciproxifan (3mg/kg, i.p.) against an impairment caused by chronic restraint stress as well as parallel exogenous corticosterone (equivalent to that seen in chronically stressed rats), and show differences in the interaction on reference and working memories tested in both aversive (Morris water maze - MWM) and appetitive (Barnes maze-BM) incentives. We found that administration of ciproxifan potently prevented equally deleterious effects of chronic restraint stress (p<0.01) as well as prolonged administration of corticosterone (p<0.01), especially in the tests, which themselves generate high levels of stress. As it turns out, test provided in the less stressful conditions (BM) showed that administration of the H3 receptor antagonist to naïve rats resulted in even memory impairment (p<0.01, in some aspects of reference memory). These data support the idea that modulation of H3 receptors represents a novel and viable therapeutic strategy in the treatment but rather not for prevention of stress-evoked cognitive impairments. Even a single dose abolishes the effect of prolonged exposure to stress or steroids.

  2. Chronic Psychological Stress Enhances Nociceptive Processing in the Urinary Bladder in High-Anxiety Rats

    PubMed Central

    Robbins, M.T.; DeBerry, J.; Ness, T.J.

    2007-01-01

    This study sought to determine whether acute and/or chronic psychological stress produce changes in urinary bladder nociception. Female Sprague-Dawley (SD; low/moderate anxiety) or Wistar-Kyoto (WK; high-anxiety) rats were exposed to either an acute (1 day) or a chronic (10 days) water avoidance stress paradigm or a sham stress paradigm. Paw withdrawal thresholds to mechanical and thermal stimuli and fecal pellet output, were quantified at baseline and after the final stress or sham stress exposure. Rats were then sedated, and visceromotor responses (VMRs) to urinary bladder distension (UBD) were recorded. While acute stress exposure did not significantly alter bladder nociceptive responses in either strain of rats, WK rats exposed to a chronic stress paradigm exhibited enhanced responses to UBD. These high-anxiety rats also exhibited somatic analgesia following acute, but not chronic, stress. Furthermore, WK rats had greater fecal pellet output than SD rats when stressed. Significant stress-induced changes in nociceptive responses to mechanical stimuli were observed in SD rats. That chronic psychological stress significantly enhanced bladder nociceptive responses only in high-anxiety rats provides further support for a critical role of genetics, stress and anxiety as exacerbating factors in painful urogenital disorders such as interstitial cystitis (IC). PMID:17521683

  3. Denver Potable Water Reuse Demonstration Project: comprehensive chronic rat study.

    PubMed

    Condie, L W; Lauer, W C; Wolfe, G W; Czeh, E T; Burns, J M

    1994-11-01

    The health effects testing program for the Denver Water Department's Potable Water Reuse Demonstration Project was designed to evaluate the relative health effects of highly treated reclaimed water derived from secondary wastewater in comparison with Denver's present high-quality drinking water. The 1 x 10(6) gal/day treatment plant provided 500-fold concentrates of water that had been treated by multiple processes to remove microbial and chemical contaminants. Fischer 344 rats were exposed to the complex mixture solutions for up to 2 yr to evaluate chronic toxicity and oncogenicity effects. The following parameters were evaluated: clinical observations, survival rate, growth, food and water consumption, haematology, clinical chemistry, urinalysis, organ weights, gross autopsy and histopathological examination of all lesions, major tissues and organs. Clinical pathology, gross pathology, and microscopic pathology conducted at wk 26 and 65 and at the end of the study did not reveal any findings that could be considered to be treatment related. Administration of drinking water concentrates at up to 500 times the original concentration in the original water samples to F344 rats for up to 104 wk did not result in any overt toxicological or carcinogenic effects. PMID:7959456

  4. Chronic cadmium exposure-induced renal anemia in ovariectomized rats.

    PubMed

    Hiratsuka, H; Katsuta, O; Toyota, N; Tsuchitani, M; Umemura, T; Marumo, F

    1996-04-01

    Cadmium (Cd) chloride was intravenously injected at doses of 0.05 and 0.5 mg/kg/day in ovariectomized rats for 50 weeks, and the chronic Cd exposure-induced nephrotoxicity and anemia were investigated. The rats treated with 0.05 mg/kg Cd showed no apparent hematological, urinary, and histopathological abnormalities. In the 0.5-mg/kg group, renal tubular disorders became marked at 16 weeks, and cortical fibrosis with glomerular dysfunction appeared at 50 weeks. Anemia occurred at 12 weeks in the 0.5-mg/kg group and became increasingly marked with time. The mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were decreased at 12 and 25 weeks; however, the decreases of MCV and MCH disappeared at 50 weeks. A slight decrease in mean corpuscular hemoglobin concentration was noted at 50 weeks. The blood chemistry from the same group revealed a decrease in plasma iron levels and an increase in total iron binding capacity throughout the administration period. The erythropoietin (EPO) level was increased as the hemoglobin level decreased at 12 weeks, whereas the EPO level was not elevated even when the hemoglobin level was decreased at 50 weeks. These findings showed that renal anemia also occurred in addition to the iron deficiency anemia at 50 weeks.

  5. Acute and chronic tramadol administration impair spatial memory in rat

    PubMed Central

    Hosseini-Sharifabad, Ali; Rabbani, Mohammad; Sharifzadeh, Mohammad; Bagheri, Narges

    2016-01-01

    Tramadol hydrochloride, a synthetic opioid, acts via a multiple mechanism of action. Tramadol can potentially change the behavioral phenomena. The present study evaluates the effect of tramadol after single or multiple dose/s on the spatial memory of rat using object recognition task (ORT). Tramadol, 20 mg/kg, was injected intraperitoneally (i.p) as a single dose or once a day for 21 successive days considered as acute or chronic treatment respectively. After treatment, animals underwent two trials in the ORT. In the first trial (T1), animals encountered with two identical objects for exploration in a five-minute period. After 1 h, in the T2 trial, the animals were exposed to a familiar and a nonfamiliar object. The exploration times and frequency of the exploration for any objects were recorded. The results showed that tramadol decreased the exploration times for the nonfamiliar object in the T2 trial when administered either as a single dose (P<0.001) or as the multiple dose (P<0.05) compared to the respective control groups. Both acute and chronic tramadol administration eliminated the different frequency of exploration between the familiar and nonfamiliar objects. Our findings revealed that tramadol impaired memory when administered acutely or chronically. Single dose administration of tramadol showed more destructive effect than multiple doses of tramadol on the memory. The observed data can be explained by the inhibitory effects of tramadol on the wide range of neurotransmitters and receptors including muscarinic, N-methyl D-aspartate, AMPA as well as some second messenger like cAMP and cGMP or its stimulatory effect on the opioid, gama amino butyric acid, dopamine or serotonin in the brain. PMID:27051432

  6. Acute and chronic tramadol administration impair spatial memory in rat.

    PubMed

    Hosseini-Sharifabad, Ali; Rabbani, Mohammad; Sharifzadeh, Mohammad; Bagheri, Narges

    2016-01-01

    Tramadol hydrochloride, a synthetic opioid, acts via a multiple mechanism of action. Tramadol can potentially change the behavioral phenomena. The present study evaluates the effect of tramadol after single or multiple dose/s on the spatial memory of rat using object recognition task (ORT). Tramadol, 20 mg/kg, was injected intraperitoneally (i.p) as a single dose or once a day for 21 successive days considered as acute or chronic treatment respectively. After treatment, animals underwent two trials in the ORT. In the first trial (T1), animals encountered with two identical objects for exploration in a five-minute period. After 1 h, in the T2 trial, the animals were exposed to a familiar and a nonfamiliar object. The exploration times and frequency of the exploration for any objects were recorded. The results showed that tramadol decreased the exploration times for the nonfamiliar object in the T2 trial when administered either as a single dose (P<0.001) or as the multiple dose (P<0.05) compared to the respective control groups. Both acute and chronic tramadol administration eliminated the different frequency of exploration between the familiar and nonfamiliar objects. Our findings revealed that tramadol impaired memory when administered acutely or chronically. Single dose administration of tramadol showed more destructive effect than multiple doses of tramadol on the memory. The observed data can be explained by the inhibitory effects of tramadol on the wide range of neurotransmitters and receptors including muscarinic, N-methyl D-aspartate, AMPA as well as some second messenger like cAMP and cGMP or its stimulatory effect on the opioid, gama amino butyric acid, dopamine or serotonin in the brain. PMID:27051432

  7. Acute and chronic tianeptine treatments attenuate ethanol withdrawal syndrome in rats.

    PubMed

    Uzbay, Tayfun; Kayir, Hakan; Celik, Turgay; Yüksel, Nevzat

    2006-05-01

    Effects of acute and chronic tianeptine treatments on ethanol withdrawal syndrome were investigated in rats. Ethanol (7.2% v/v) was given to adult male Wistar rats by a liquid diet for 30 days. Acute or chronic (twice daily) tianeptine (5, 10 and 20 mg/kg) and saline were administered to rats intraperitoneally. Acute and last chronic tianeptine injections and saline were done 30 min before ethanol withdrawal testing. After 2nd, 4th and 6th hours of ethanol withdrawal, rats were observed for 5 min, and withdrawal signs which included locomotor hyperactivity, agitation, tremor, wet dog shakes, stereotyped behavior and audiogenic seizures were recorded or rated. Locomotor activity in naive (no ethanol-dependent rats) was also tested after acute tianeptine treatments. Acute but not chronic tianeptine treatment attenuated locomotor hyperactivity and agitation in ethanol-dependent rats. Both acute and chronic tianeptine treatment produced some significant inhibitory effects on tremor, wet dog shakes, stereotyped behaviors and audiogenic seizures during the ethanol withdrawal. Our results suggest that acute or chronic tianeptine treatment attenuates ethanol withdrawal syndrome in ethanol-dependent rats and this drug may be useful for treatment of ethanol-type dependence.

  8. Chronic ethanol consumption depresses hypothalamic-pituitary-adrenal function in aged rats

    SciTech Connect

    Nolan, C.J.; Bestervelt, L.L.; Mousigian, C.A.; Maimansomsuk, P.; Yong Cai; Piper, W.N. )

    1991-01-01

    In separate experiments, nine (n=20) and fifteen (n=12) month old rats were treated with either 6% ethanol or 12% sucrose in the drinking water to examine the effect of chronic ethanol consumption on the hypothalamic-pituitary-adrenal axis of aged rats. Blood was collected and plasma concentrations of adrenocorticotropin (ACTH) and corticosterone were determined by radioimmunoassay. Adrenal glands were cleaned, quartered and used to test in vitro responsiveness to ACTH. Anterior pituitary glands from all 15 month old rats and one half of the nine month old rats were collected, frozen and extracted for measurement of tissue ACTH concentration. The remaining anterior pituitary glands from the nine month old rats were challenged with corticotropin releasing hormone (CRH) to test in vitro responsiveness. In nine month old rats, chronic ethanol consumption decreased plasma ACTH and corticosterone. Pituitary ACTH concentrations were unchanged in treated nine month old rats, but the amount of pituitary ACTH released in response to CRH was decreased in rats consuming ethanol. In vitro responsiveness of the adrenal gland to ACTH in nine month old rats consuming ethanol was unchanged. Plasma ACTH and corticosterone concentrations were also decreased in 15 month old rats chronically consuming ethanol. No differences were noted in responsiveness of the adrenal gland or in the amount of pituitary ACTH due to ethanol consumptions in 15 month old rats.

  9. Probiotic amelioration of azotemia in 5/6th nephrectomized Sprague-Dawley rats.

    PubMed

    Ranganathan, Natarajan; Patel, Beena; Ranganathan, Pari; Marczely, Joseph; Dheer, Rahul; Chordia, Tushar; Dunn, Stephen R; Friedman, Eli A

    2005-08-24

    The present study was to test the hypothesis that, selected bacteria instilled into the gastrointestinal tract could help in converting nitrogenous wastes accumulated due to renal insufficiency into non-toxic compounds; thereby, ameliorating the biochemical imbalance. Herein we describe a prospective, blinded, placebo controlled pilot-study, using 5/6th nephrectomized Sprague Dawley rat, as a chronic renal failure model. The study group consisted of 36 nephrectomized and 7 non-nephrectomized (control) rats. After two-week nephrectomy stabilization, cohorts of six nephrectomized rats were fed casein-based diet plus one of the following regimens: (A) Control, (B) Placebo (casein-based diet without probiotics), (C) Bacillus pasteurii, (D) Sporolac(R), (E) Kibow cocktail, (F) CHR Hansen Cocktail, and (G) ECONORM. Subsequently, blood (retro-orbital) and urine (collected for measurements of blood urea-nitrogen and creatinine respectively), body weight and bacterial counts (feces) were obtained at regular intervals. The study end-points were to determine if any of the probiotic dietary supplements facilitated, (1) decreased blood concentrations of uremic toxins, (2) altered renal function, and (3) prolonged survival. After 16 weeks of treatment, regimens C and D significantly prolonged the life span of uremic rats, in addition to showing a reduction in blood urea-nitrogen levels, concluding that supplementation of probiotic formulation to uremic rats slows the progression of azotemia, which may correlate with prolonged life span of uremic rats. Derivative trials of probiotic treatment of larger animals and humans will further assess the potential role of probiotic formulations in delaying the onset and clinical severity of clinical illness at different stages of renal failure. PMID:16127597

  10. Functional Genomic Analysis Identifies Indoxyl Sulfate as a Major, Poorly Dialyzable Uremic Toxin in End-Stage Renal Disease

    PubMed Central

    Jhawar, Sachin; Singh, Prabhjot; Torres, Daniel; Ramirez-Valle, Francisco; Kassem, Hania; Banerjee, Trina; Dolgalev, Igor; Heguy, Adriana; Zavadil, Jiri; Lowenstein, Jerome

    2015-01-01

    Background Chronic renal failure is characterized by progressive renal scarring and accelerated arteriosclerotic cardiovascular disease despite what is considered to be adequate hemodialysis or peritoneal dialysis. In rodents with reduced renal mass, renal scarring has been attributed to poorly filtered, small protein-bound molecules. The best studied of these is indoxyl sulfate (IS). Methods We have attempted to establish whether there are uremic toxins that are not effectively removed by hemodialysis. We examined plasma from patients undergoing hemodialysis, employing global gene expression in normal human renal cortical cells incubated in pre- and post- dialysis plasma as a reporter system. Responses in cells incubated with pre- and post-dialysis uremic plasma (n = 10) were compared with responses elicited by plasma from control subjects (n = 5). The effects of adding IS to control plasma and of adding probenecid to uremic plasma were examined. Plasma concentrations of IS were measured by HPLC (high pressure liquid chromatography). Results Gene expression in our reporter system revealed dysregulation of 1912 genes in cells incubated with pre-dialysis uremic plasma. In cells incubated in post-dialysis plasma, the expression of 537 of those genes returned to baseline but the majority of them (1375) remained dysregulated. IS concentration was markedly elevated in pre- and post-dialysis plasma. Addition of IS to control plasma simulated more than 80% of the effects of uremic plasma on gene expression; the addition of probenecid, an organic anion transport (OAT) inhibitor, to uremic plasma reversed the changes in gene expression. Conclusion These findings provide evidence that hemodialysis fails to effectively clear one or more solutes that effect gene expression, in our reporter system, from the plasma of patients with uremia. The finding that gene dysregulation was simulated by the addition of IS to control plasma and inhibited by addition of an OAT inhibitor to

  11. Managing atypical hemolytic uremic syndrome: chapter 2.

    PubMed

    Nester, Carla M

    2015-05-01

    Licht et al. present the 2-year follow-up data of the landmark trials studying the efficacy of eculizumab in the treatment of atypical hemolytic uremic syndrome (aHUS). They report sustained improvements in hematologic parameters, continued safety, and additional improvements in kidney function with extended treatment. This report adds a layer of comfort to our care of patients with this rare disease; however, it is unlikely to be the final chapter in the treatment of aHUS.

  12. Effect of acute and chronic hypernatremia on myoinositol and sorbitol concentration in rat brain and kidney.

    PubMed

    Lohr, J W; McReynolds, J; Grimaldi, T; Acara, M

    1988-01-01

    In animal models of hypernatremia, increases in brain electrolyte content account for the entire increase in osmolality in acute but not chronic hypernatremia, suggesting that there is generation of additional intracellular solutes ("idiogenic osmoles") in chronic hypernatremic states. In the present study, the concentration of the polyols myoinositol and sorbitol and water content were determined in the brain and kidneys of rats made acutely (2 hours) and chronically (72 hours) hypernatremic by intraperitoneal injection of NaCl and water restriction. Both the brain and the kidney responded to chronic hypernatremia with increased levels of myoinositol. Sorbitol levels increased in the kidney in response to both acute and chronic hypernatremia. Water content dropped in acute hypernatremia, but remained unchanged during chronic hyperosmolar challenge. We conclude that the polyols, myoinositol and sorbitol, may play a significant role in cellular osmoregulation in brain and kidney during chronic hypernatremia in the rat.

  13. Bioengineered kidney tubules efficiently excrete uremic toxins

    PubMed Central

    Jansen, J.; Fedecostante, M.; Wilmer, M. J.; Peters, J. G.; Kreuser, U. M.; van den Broek, P. H.; Mensink, R. A.; Boltje, T. J.; Stamatialis, D.; Wetzels, J. F.; van den Heuvel, L. P.; Hoenderop, J. G.; Masereeuw, R.

    2016-01-01

    The development of a biotechnological platform for the removal of waste products (e.g. uremic toxins), often bound to proteins in plasma, is a prerequisite to improve current treatment modalities for patients suffering from end stage renal disease (ESRD). Here, we present a newly designed bioengineered renal tubule capable of active uremic toxin secretion through the concerted action of essential renal transporters, viz. organic anion transporter-1 (OAT1), breast cancer resistance protein (BCRP) and multidrug resistance protein-4 (MRP4). Three-dimensional cell monolayer formation of human conditionally immortalized proximal tubule epithelial cells (ciPTEC) on biofunctionalized hollow fibers with maintained barrier function was demonstrated. Using a tailor made flow system, the secretory clearance of human serum albumin-bound uremic toxins, indoxyl sulfate and kynurenic acid, as well as albumin reabsorption across the renal tubule was confirmed. These functional bioengineered renal tubules are promising entities in renal replacement therapies and regenerative medicine, as well as in drug development programs. PMID:27242131

  14. Salivary Alterations in Rats with Experimental Chronic Kidney Disease

    PubMed Central

    Romero, Ana Carolina; Bergamaschi, Cassia Toledo; de Souza, Douglas Nesadal; Nogueira, Fernando Neves

    2016-01-01

    Objective This study aimed to analyze changes in saliva composition and salivary secretion process of rats with chronic kidney disease induced by 5/6 nephrectomy to set the foundation for salivary studies related to CKD. Methods CKD was induced in Wistar rats via 5/6 nephrectomy. Blood and saliva samples were collected from Control, Sham and CKD groups at 8 and 12 weeks after the surgery. Salivation was stimulated via intraperitoneal injections of pilocarpine (1.0 mg/Kg body weight) or isoproterenol (5.0 mg/Kg body weight). Saliva was collected and immediately stored at -80°C until analysis. The salivary flow rate, total protein, amylase and peroxidase activities, and urea concentrations were measured. The blood urea nitrogen (BUN) and serum creatinine concentrations were also evaluated. Results Increases in BUN and serum creatinine concentrations were observed in the CKD groups. Amylase activity was significantly reduced in response to both stimuli in the CKD groups at 8 weeks and increased in the CKD groups at 12 weeks in response to isoproterenol stimulus. The peroxidase activities of the CKD groups were significantly reduced in response to isoproterenol stimulation and were increased at 12 weeks in response to pilocarpine stimulation. Salivary urea was significantly increased in the CKD groups at 8 weeks in response to the isoproterenol stimuli and at 12 weeks in response to both salivary agonists. Conclusions The pattern of alterations observed in this experimental model is similar to those observed in patients and clearly demonstrates the viability of 5/6 nephrectomy as an experimental model in future studies to understand the alterations in salivary compositions and in salivary glands that are elicited by CKD. PMID:26859883

  15. Proteomic analysis of liver in rats chronically exposed to fluoride.

    PubMed

    Pereira, Heloísa Aparecida Barbosa da Silva; Leite, Aline de Lima; Charone, Senda; Lobo, Janete Gualiume Vaz Madureira; Cestari, Tania Mary; Peres-Buzalaf, Camila; Buzalaf, Marília Afonso Rabelo

    2013-01-01

    Fluoride (F) is a potent anti-cariogenic element, but when ingestion is excessive, systemic toxicity may be observed. This can occur as acute or chronic responses, depending on both the amount of F and the time of exposure. The present study identified the profile of protein expression possibly associated with F-induced chronic hepatotoxicity. Weanling male Wistar rats (three-weeks old) were divided into three groups and treated with drinking water containing 0, 5 or 50 mg/L F for 60 days (n=6/group). At this time point, serum and livers were collected for F analysis, which was done using the ion-sensitive electrode, after hexamethyldisiloxane-facilitated diffusion. Livers were also submitted to histological and proteomic analyses (2D-PAGE followed by LC-MS/MS). Western blotting was done for confirmation of the proteomic data A dose-response was observed in serum F levels. In the livers, F levels were significantly increased in the 50 mg/L F group compared to groups treated with 0 and 5 mg/L F. Liver morphometric analysis did not reveal alterations in the cellular structures and lipid droplets were present in all groups. Proteomic quantitative intensity analysis detected 33, 44, and 29 spots differentially expressed in the comparisons between control vs. 5 mg/L F, control vs. 50 mg/L F, and 5 mg/L vs. 50 mg/L F, respectively. From these, 92 proteins were successfully identified. In addition, 18, 1, and 5 protein spots were shown to be exclusive in control, 5, and 50 mg/L F, respectively. Most of proteins were related to metabolic process and pronounced alterations were seen for the high-F level group. In F-treated rats, changes in the apolipoprotein E (ApoE) and GRP-78 expression may account for the F-induced toxicity in the liver. This can contribute to understanding the molecular mechanisms underlying hepatoxicity induced by F, by indicating key-proteins that should be better addressed in future studies.

  16. Green tea polyphenols attenuate deterioration of bone microarchitecture in female rats with systemic chronic inflammation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Our previous study demonstrated that green tea polyphenols (GTP) benefit bone health in female rats with chronic inflammation, because of GTP’s antioxidant capacity. The current study further evaluates whether GTP can restore bone microstructure along with related mechanism in rats wit...

  17. Sympathoadrenal responses to acute and chronic hypoxia in the rat.

    PubMed Central

    Johnson, T S; Young, J B; Landsberg, L

    1983-01-01

    The sympathoadrenal responses to acute and chronic hypoxic exposure at 10.5 and 7.5% oxygen were determined in the rat. Cardiac norepinephrine (NE) turnover was used to assess sympathetic nervous system (SNS) activity, and urinary excretion of epinephrine (E) was measured as an index of adrenal medullary activity. The responses of the adrenal medulla and SNS were distinct and dependent upon the degree and duration of hypoxic exposure. Chronic hypoxia at 10.5% oxygen increased cardiac NE turnover by 130% after 3, 7, and 14 d of hypoxic exposure. Urinary excretion of NE was similarly increased over this time interval, while urinary E excretion was marginally elevated. In contrast, acute exposure to moderate hypoxia at 10.5% oxygen was not associated with an increase in SNS activity; in fact, decreased SNS activity was suggested by diminished cardiac NE turnover and urinary NE excretion over the first 12 h of hypoxic exposure, and by a rebound increase in NE turnover after reexposure to normal oxygen tension. Adrenal medullary activity, on the other hand, increased substantially during acute exposure to moderate hypoxia (2-fold increase in urinary E excretion) and severe hypoxia (greater than 10-fold). In distinction to the lack of effect of acute hypoxic exposure (10.5% oxygen), the SNS was markedly stimulated during the first day of hypoxia exposure at 7.5% oxygen, an increase that was sustained throughout at least 7 d at 7.5% oxygen. These results demonstrate that chronic exposure to moderate and severe hypoxia increases the activity of the SNS and adrenal medulla, the effect being greater in severe hypoxic exposure. The response to acute hypoxic exposure is more complicated; during the first 12 h of exposure at 10.5% oxygen, the SNS is not stimulated and appears to be restrained, while adrenal medullary activity is enhanced. Acute exposure to a more severe degree of hypoxia (7.5% oxygen), however, is associated with stimulation of both the SNS and adrenal medulla

  18. Brain vasopressin V(1) receptors contribute to enhanced cardiovascular responses to acute stress in chronically stressed rats and rats with myocardial infarcton.

    PubMed

    Cudnoch-Jedrzejewska, Agnieszka; Szczepanska-Sadowska, Ewa; Dobruch, Jakub; Gomolka, Ryszard; Puchalska, Liana

    2010-03-01

    The present study was designed to determine the role of central vasopressin 1 receptors (V(1)R) in the regulation of cardiovascular parameters in chronically stressed infarcted rats and sham-operated rats under resting conditions and during exposure to acute alarming stress. The experiments were performed on four groups of conscious sham-operated and four groups of infarcted rats subjected to intraventricular infusion of either vehicle or a V(1)R antagonist (V(1)RANT). Two groups of infarcted and two groups of sham-operated rats were subjected to mild chronic stressing. Mean arterial blood pressure (MABP) and heart rate (HR) were determined under resting conditions and after exposure to acute stress (air jet). During vehicle infusion, MABP and HR increases in response to acute stress in the infarcted rats not subjected to chronic stress, and in the infarcted and sham-operated chronically stressed rats, were significantly greater than in the sham-operated rats not exposed to chronic stress. However, MABP and HR responses to acute stress in the chronically stressed infarcted rats and chronically stressed sham-operated rats did not differ. V(1)RANT abolished differences in cardiovascular responses to acute stress between the experimental groups. Resting cardiovascular parameters were not affected by any of the experimental treatments. It is concluded that chronic stressing enhances the pressor and tachycardic responses to acute stress in the sham-operated rats but does not further intensify these responses in infarcted rats.The results provide evidence that central V(1)Rs are involved in potentiation of cardiovascular responses to acute stress in chronically stressed rats, infarcted rats, and chronically stressed infarcted rats.

  19. Green tea polyphenols avert chronic inflammation-induced myocardial fibrosis of female rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: Green tea proposes anti-inflammatory properties which may attenuate chronic inflammation-induced fibrosis of vessels. This study evaluated whether green tea polyphenols (GTP) can avert fibrosis or vascular disruption along with mechanisms in rats with chronic inflammation. Treatments: Fo...

  20. Effects of chronic cocaine in rat C6 astroglial cells

    PubMed Central

    BADISA, RAMESH B.; GOODMAN, CARL B.

    2012-01-01

    Investigations with astroglial cells carry equal importance as those with neurons in drug abuse studies. The present study was aimed to investigate the effect of chronic cocaine administration on cell viability, nitric oxide (NO) production, general respiratory status of mitochondria and total protein levels in rat astroglioma cells after 24 h of treatment. In addition, the effect of cocaine was assessed for 24 h on brine shrimp larvae in order to study their sensitivity to the drug. It was observed that cocaine caused a significant dose-dependent decrease in astroglial cell viability with an LC50 of 4.717 mM. It was found that cocaine did not induce or inhibit NO production in the cells. Evaluation of mitochondrial dehydrogenase activity in terms of formazan production in astroglial cells indicated that cocaine significantly interfered with the general respiratory status of mitochondria with an ED50 of 6.153 mM. Furthermore, cocaine was shown to deplete the total protein levels in the cells with an ED50 of 5.435 mM. In vivo study with brine shrimp larvae showed that these larvae were highly sensitive to cocaine with an ED50 of 2.41 mM. In summary, our findings suggest that cocaine-induced cytotoxicity in the cells was non-specific. The cumulative effect arising from the significant loss of respiration and total cellular proteins is the cause of astroglial cell death. PMID:22735768

  1. Effects of chronic cocaine in rat C6 astroglial cells.

    PubMed

    Badisa, Ramesh B; Goodman, Carl B

    2012-09-01

    Investigations with astroglial cells carry equal importance as those with neurons in drug abuse studies. The present study was aimed to investigate the effect of chronic cocaine administration on cell viability, nitric oxide (NO) production, general respiratory status of mitochondria and total protein levels in rat astroglioma cells after 24 h of treatment. In addition, the effect of cocaine was assessed for 24 h on brine shrimp larvae in order to study their sensitivity to the drug. It was observed that cocaine caused a significant dose-dependent decrease in astroglial cell viability with an LC(50) of 4.717 mM. It was found that cocaine did not induce or inhibit NO production in the cells. Evaluation of mitochondrial dehydrogenase activity in terms of formazan production in astroglial cells indicated that cocaine significantly interfered with the general respiratory status of mitochondria with an ED(50) of 6.153 mM. Furthermore, cocaine was shown to deplete the total protein levels in the cells with an ED(50) of 5.435 mM. In vivo study with brine shrimp larvae showed that these larvae were highly sensitive to cocaine with an ED(50) of 2.41 mM. In summary, our findings suggest that cocaine-induced cytotoxicity in the cells was non-specific. The cumulative effect arising from the significant loss of respiration and total cellular proteins is the cause of astroglial cell death. PMID:22735768

  2. Endogenous cardiotonic steroids in chronic renal failure

    PubMed Central

    Kolmakova, Elena V.; Haller, Steven T.; Kennedy, David J.; Isachkina, Alina N.; Budny, George V.; Frolova, Elena V.; Piecha, Grzegorz; Nikitina, Elena R.; Malhotra, Deepak; Fedorova, Olga V.; Shapiro, Joseph I.

    2011-01-01

    Background. Previous reports demonstrated that digitalis-like cardiotonic steroids (CTS) contribute to the pathogenesis of end-stage renal disease. The goal of the present study was to define the nature of CTS in patients with chronic kidney disease (CKD) and in partially nephrectomized (PNx) rats. Methods. In patients with CKD and in healthy controls, we determined plasma levels of marinobufagenin (MBG) and endogenous ouabain (EO) and erythrocyte Na/K-ATPase activity in the absence and in the presence of 3E9 anti-MBG monoclonal antibody (mAb) and Digibind. Levels of MBG and EO were also determined in sham-operated Sprague–Dawley rats and in rats following 4 weeks of PNx. Results. In 25 patients with CKD plasma, MBG but not EO was increased (0.86 ± 0.07 versus 0.28 ± 0.02 nmol/L, P < 0.01) and erythrocyte Na/K-ATPase was inhibited (1.24 ± 0.10 versus 2.80 ± 0.09 μmol Pi/mL/h, P < 0.01) as compared to that in 19 healthy subjects. Ex vivo, 3E9 mAb restored Na/K-ATPase in erythrocytes from patients with CKD but did not affect Na/K-ATPase from control subjects. Following chromatographic fractionation of uremic versus normal plasma, a competitive immunoassay based on anti-MBG mAb detected a 3-fold increase in the level of endogenous material having retention time similar to that seen with MBG. A similar pattern of CTS changes was observed in uremic rats. As compared to sham-operated animals, PNx rats exhibited 3-fold elevated levels of MBG but not that of EO. Conclusions. In chronic renal failure, elevated levels of a bufadienolide CTS, MBG, contribute to Na/K-ATPase inhibition and may represent a potential target for therapy. PMID:21292813

  3. Zeta Inhibitory Peptide as a Novel Therapy to Control Chronic Visceral Hypersensitivity in a Rat Model

    PubMed Central

    Chen, Yu; Guo, Lixia; Dai, Hengfen; Huang, Yang; Chen, Qianqian; Lin, Chun

    2016-01-01

    Background The pathogenesis of multiple chronic visceral pain syndromes, such as irritable bowel syndrome (IBS), is not well known, and as a result current therapies are ineffective. The objective of this study was to investigate the effect of spinal protein kinase M zeta (PKMζ) on visceral pain sensitivity in rats with IBS to better understand the pathogenesis and investigate the effect of zeta inhibitory peptide (ZIP) as a therapy for chronic visceral pain. Methods Visceral hypersensitivity rats were produced by neonatal maternal separation (NMS). Visceral pain sensitivity was assessed by electromyographic (EMG) responses of abdominal muscles to colorectal distention (CRD). Spinal PKMζ and phosphorylated PKMζ (p-PKMζ) were detected by western blot. Varying doses of ZIP were intrathecally administered to investigate the role of spinal PKMζ in chronic visceral hypersensitivity. The open field test was used to determine if ZIP therapy causes spontaneous motor activity side effects. Results Graded CRD pressure significantly increased EMG responses in NMS rats compared to control rats (p < 0.05). p-PKMζ expression increased in the thoracolumbar and lumbosacral spinal cord in the IBS-like rats with notable concomitant chronic visceral pain compared to control rats (p < 0.05). EMG data revealed that intrathecal ZIP injection (1, 5, and 10 μg) dose-dependently attenuated visceral pain hypersensitivity in IBS-like rats. Conclusions Phosphorylated PKMζ may be involved in the spinal central sensitization of chronic visceral hypersensitivity in IBS, and administration of ZIP could effectively treat chronic visceral pain with good outcomes in rat models. PMID:27776136

  4. Both acute and chronic buspirone treatments have different effects on regional 5-HT synthesis in Flinders Sensitive Line rats (a rat model of depression) than in control rats

    PubMed Central

    Nishi, Kyoko; Kanemaru, Kazuya; Hasegawa, Shu; Watanabe, Arata; Diksic, Mirko

    2009-01-01

    The main objective of this investigation was to evaluate the effects of buspirone, a 5-HT1A agonist with some partial agonist properties and also an antidepressant, on regional 5-HT synthesis in Flinders Sensitive Line (FSL) rats (“depressed”), and to compare the effects to the Flinders Resistant Line (FRL) control rats (not “depressed”). In addition results were compared to those previously reported in normal Sprague-Dawley (SPD) rats (normal control). Serotonin synthesis in both FSL and FRL rats was measured following acute and chronic treatments with buspirone. Both of these strains were derived from the SPD rats. No direct comparison was done between the FSL saline and FRL saline groups, or the FSL buspirone and FRL buspirone groups, because the objective of the studies was to evaluate effects of buspirone in these two strains. The results show that acute treatment with buspirone elevates 5-HT synthesis throughout the brain in the FRL rats. In the FSL rats, there were reductions in some brain regions (e.g., dorsal and median raphe, amygdala, anterior olfactory nucleus, substantia nigra reticulate), while in other regions, there were increases in the synthesis observed (e.g., frontal, parietal, visual and somatosensory cortices, ventral hippocampus). In twenty out of the thirty brain regions investigated in the FSL rats, there was no significant change in the synthesis following acute buspirone treatment. During the chronic treatment, buspirone produced a significant reduction of 5-HT synthesis in fifteen out of thirty brain regions in the FRL rats. In the FSL rats, buspirone produced a significant elevation of the synthesis in ten out of thirty brain regions. In both the FSL and FRL rats, buspirone produced rather different effects than those reported previously for SPD (normal) rats. The acute effect in the FSL rats was somewhat similar to the effect reported previously for the SPD rats, while in the FRL rats, the acute buspirone treatment produced an

  5. Protective effect of oxymatrine on chronic rat heart failure.

    PubMed

    Hu, Shu-Ting; Tang, Ying; Shen, Ya-Feng; Ao, Hai-Hang; Bai, Jie; Wang, Yong-Liang; Yang, Yong-Ji

    2011-09-01

    Oxymatrine is one of the alkaloids extracted from the Chinese herb Sophora japonica (Sophora flavescens Ait.) with anti-inflammatory, immune reaction inhibiting, antiviral, and hepatocyte and antihepatic fibrosis protective activities. However, the effect of oxymatrine on heart failure is not yet known. In this study, the effect of oxymatrine on heart failure was investigated using a Sprague-Dawley rat model of chronic heart failure. Morphological findings showed that in the group treated with 50 and 100 mg/kg of oxymatrine; intermyofibrillar lysis disappeared, myofilaments were orderly, closely and evenly arranged; and mitochondria contained tightly packed cristae compared with the heart failure group. We investigated the cytosolic Ca(2+) transients and sarcoplasmic reticulum (SR) Ca(2+) content, and assessed the expression of ryanodine receptor (RyR2), SR-Ca(2+) ATPase (SERCA2a), and L-type Ca(2+) channel (dihydropyridine receptor, DHPR). We found that the cytosolic Ca(2+) transients were markedly increased in amplitude in the medium- (ΔF/F (0) = 26.22 ± 2.01) and high-dose groups (ΔF/F (0) = 29.49 ± 1.17) compared to the heart failure group (ΔF/F (0) = 12.12 ± 1.35, P < 0.01), with changes paralleled by a significant increase in the SR Ca(2+) content (medium-dose group: ΔF/F (0) = 32.20 ± 1.67, high-dose group: ΔF/F (0) = 32.57 ± 1.29, HF: ΔF/F (0) = 17.26 ± 1.05, P < 0.01). Moreover, we demonstrated that the expression of SERCA2a and cardiac DHPR was significantly increased in the medium- and high-dose group compared with the heart failure rats. These findings suggest that oxymatrine could improve heart failure by improving the cardiac function and that this amelioration is associated with upregulation of SERCA2a and DHPR. PMID:21691940

  6. A Brain Signature to Differentiate Acute and Chronic Pain in Rats

    PubMed Central

    Guo, Yifei; Wang, Yuzheng; Sun, Yabin; Wang, Jin-Yan

    2016-01-01

    The transition from acute pain to chronic pain entails considerable changes of patients at multiple levels of the nervous system and in psychological states. An accurate differentiation between acute and chronic pain is essential in pain management as it may help optimize analgesic treatments according to the pain state of patients. Given that acute and chronic pain could modulate brain states in different ways and that brain states could greatly shape the neural processing of external inputs, we hypothesized that acute and chronic pain would show differential effects on cortical responses to non-nociceptive sensory information. Here by analyzing auditory-evoked potentials (AEPs) to pure tones in rats with acute or chronic pain, we found opposite influences of acute and chronic pain on cortical responses to auditory inputs. In particular, compared to no-pain controls, the N100 wave of rat AEPs was significantly enhanced in rats with acute pain but significantly reduced in rats with chronic pain, indicating that acute pain facilitated cortical processing of auditory information while chronic pain exerted an inhibitory effect. These findings could be justified by the fact that individuals suffering from acute or chronic pain would have different vigilance states, i.e., the vigilance level to external sensory stimuli would be increased with acute pain, but decreased with chronic pain. Therefore, this auditory response holds promise of being a brain signature to differentiate acute and chronic pain. Instead of investigating the pain system per se, the study of pain-induced influences on cortical processing of non-nocicpetive sensory information might represent a potential strategy to monitor the progress of pain chronification in clinical applications. PMID:27199727

  7. Alterations in trace elements and oxidative stress in uremic patients with dementia.

    PubMed

    Guo, Chih-Hung; Ko, Wang-Sheng; Chen, Pei-Chung; Hsu, Guoo-Shyng W; Lin, Chia-Yeh; Wang, Chia-Liang

    2009-10-01

    The present study was conducted to compare the trace elements and oxidative status between uremic patients with and without dementia. Chronic hemodialysis patients with dementia (n = 20) and without dementia (n = 25), and age-matched healthy volunteers (n = 20) were enrolled. The nutritional status, blood levels of trace elements aluminum (Al), zinc (Zn), copper (Cu), magnesium (Mg) and iron (Fe), malondialdehyde (MDA), and protein carbonyl production, antioxidant enzymes glutathione peroxidase (GPx), and glutathione reductase (GR) activities were measured. No significant difference in nutritional status or clinical characteristics was observed between nondementia and dementia patients. However, uremic patients with dementia have significantly higher Al, Cu, and Mg and lower Zn concentrations, as well as increased Cu/Zn ratio in comparison to nondementia patients. There were statistically significant increased MDA and carbonyl production and decreased GPx and GR activities in dementia patients. Furthermore, the significant associations of Al, Mg, and Cu/Zn ratio with oxidative status in patients with dementia were noted. The dementia may initially worsen with abnormal metabolism of trace elements and oxidative stress occurrence. Our results suggest that abnormalities in trace element levels are associated with oxidative stress and may be a major risk factor in the dementia development of uremic patients.

  8. The effect of acute and chronic hypoxia on thoracic gas volume in anaesthetized rats.

    PubMed Central

    Barer, G R; Herget, J; Sloan, P J; Suggett, A J

    1978-01-01

    1. Thoracic gas volume at end expiration (functional residual capacity, FRC) was measured in chronically and acutely hypoxic anaesthetized rats by a plethysmograph method. 2. FRC, measured during air breathing, was 34-62% larger in rats which had been kept in an environmental chamber in 8, 10 or 12% O2 for 3 weeks than in littermate controls. FRC returned to normal after the rats had returned to air for 9 days. There was no constant difference in the pattern of breathing between control and chronically hypoxic rats. 3. Pressure-volume curves measured post mortem showed no difference in the volume of the lung at 25 cm H2O pressure or in the compliance of the lung between chronically hypoxic and control rats. Thus there was no gross mechanical change in the lung to account for the increase in FRC. 4. Acute hypoxia caused by breathing 12% O2 increased FRC in control but not in chronically hypoxic rats. The increase in FRC in control rats was abolished by combined blockade of the vagus nerves and carotid bodies (with procaine) but not by vagal blockade alone. 5. The combined vagal and carotid body blockade reduced FRC significantly in rats which had been in 10% O2 for 3 days but not in those which had been in 10% O2 for 21 days. 6. Lung area measured from radiographs was not reduced by a muscle relaxant in chronically hypoxic rats. Electromyograms from anterior intercostal muscles and the diaphragm showed no electrical activity in expiration in chronically hypoxic rats which might indicate an active muscular basis for their increased FRC. However when FRC was raised by acute hypoxia in control animals there was also no increase in electrical activity in expiration which could have explained their increase in lung volume. 7. We concluded that the increase in FRC during acute hypoxia in control rats was probably due to a reflex from the carotid body. The increase in FRC in chronically hypoxic rats, which was present while they breathed air, may have had an active

  9. Shiga toxin associated hemolytic uremic syndrome.

    PubMed

    Keir, Lindsay Susan

    2015-06-01

    Shiga toxin associated hemolytic uremic syndrome (Stx HUS), a thrombotic microangiopathy, is the most common cause of pediatric acute kidney injury but has no direct treatment. A better understanding of disease pathogenesis may help identify new therapeutic targets. For this reason, the role of complement is being actively studied while eculizumab, the C5 monoclonal antibody, is being used to treat Stx HUS but with conflicting results. A randomized controlled trial would help properly evaluate its use in Stx HUS while more research is required to fully evaluate the role complement plays in the disease pathogenesis.

  10. Acetyl-L-Carnitine: chronic treatment improves spatial acquisition in a new environment in aged rats.

    PubMed

    Caprioli, A; Markowska, A L; Olton, D S

    1995-07-01

    Chronic Acetyl-L-Carnitine (ALCAR) treatment prevents some age-related memory impairment. The present experiment examined the effects of aging and ALCAR in Fischer 344 rats on retention of spatial discrimination test in a familiar environment (FE), and on the acquisition of a spatial discrimination in a novel environment (NE). Rats 18 months or 3 months old were trained with a new procedure to assess spatial discrimination in the Morris water maze. Performance during acquisition in FE was used to assign each old rat to one of two classes: Good Performers (GP) and Poor Performers (PP) based on their swim time to reach the platform. The old rats displayed heterogeneous performance and a spatial discrimination deficit. Chronic ALCAR treatment enhanced spatial acquisition in the NE of rats with age-related behavioral impairments and had a slight effect on retention of the spatial discrimination in the FE.

  11. Effects of Chronic Electroacupuncture on Depression- and Anxiety-Like Behaviors in Rats with Chronic Neuropathic Pain

    PubMed Central

    Li, Qian; Yue, Na; Liu, Shen-Bin; Wang, Zhi-Fu; Mi, Wen-Li; Jiang, Jian-Wei; Wu, Gen-Cheng; Yu, Jin; Wang, Yan-Qing

    2014-01-01

    Growing evidence indicates that chronic neuropathic pain is frequently accompanied by an array of psychiatric diseases, such as depression and anxiety. Electroacupuncture (EA), as one therapy of traditional Chinese medicine, has displayed potent antidepressant-like effects in numerous clinical studies. The present study was designed to examine the possible effects of EA on the depressive and anxiety disorders induced by neuropathic pain. A classic rat model of neuropathic pain was produced by chronic constriction injury (CCI) of the sciatic nerve. EA was performed on acupoints “Bai-Hui” (GV20) and unilateral “Yang-Ling-Quan” (GB34). The antidepressive and anxiolytic effects of EA treatment were analyzed using the forced swimming test (FST) and the elevated plus maze (EPM) test, respectively. CCI resulted in remarkable depression- and anxiety-like behaviors, whereas the chronic EA treatment significantly improved the behavioral deficits of CCI rats. Moreover, the phosphorylation level of the NMDA receptor type 1 (NR1) subunit was decreased in the hippocampus of CCI rats. Intriguingly, continuous EA treatment effectively blocked this decrease in the levels of pNR1. These results suggested that EA has antidepressive and anxiolytic effects on rats with neuropathic pain and that this might be associated with restoring the phosphorylation of NR1 in the hippocampus. PMID:24795763

  12. Octreotide ameliorates gastric lesions in chronically mild stressed rats

    PubMed Central

    Nassar, Noha N; Schaalan, Mona F; Zaki, Hala F; Abdallah, Dalaal M

    2011-01-01

    AIM: To evaluate the effect of chronic mild stress (CMS) on the emergence of gastric ulcers and possible modulation by octreotide, a synthetic somatostatin analogue. METHODS: Adult male Wistar rats were subjected to nine different unpredictable random stress procedures for 21 d, a multifactorial interactional animal model for CMS. Octreotide was administered daily for 21 d at two dose levels (50 and 90 μg/kg) before exposure to stress procedure. Macro- and microscopical assessments were made, in addition to quantification of plasma corticosterone and gastric mucosal inflammatory, oxidative stress, and apoptotic biomarkers. RESULTS: Exposure to CMS elevated plasma corticosterone (28.3 ± 0.6 μg/dL, P = 0.002), an event that was accompanied by gastric lesions (6.4 ± 0.16 mm, P = 0.01) and confirmed histopathologically. Moreover, the insult elevated gastric mucosal lipid peroxides (13 ± 0.5 nmol/g tissue, P = 0.001), tumor necrosis factor-α (3008.6 ± 78.18 pg/g tissue, P < 0.001), prostaglandin E2 (117.1 ± 4.31 pg/g tissue, P = 0.002), and caspase-3 activity (2.4 ± 0.14 OD/mg protein, P = 0.002). Conversely, CMS mitigated interleukin-10 (627.9 ± 12.82 pg/g tissue, P = 0.001). Furthermore, in animals exposed to CMS, octreotide restored plasma corticosterone (61% and 71% from CMS, P = 0.002) at both dose levels. These beneficial effects were associated with a remarkable suppression of gastric lesions (38% and 9% from CMS, P = 0.01) and reversal of derangements in gastric mucosa. CONCLUSION: The current investigation provides evidence that exposure to CMS induces gastric ulceration, which was alleviated by administration of octreotide possibly possessing antioxidant, anti-inflammatory, and anti-apoptotic actions. PMID:21448417

  13. Middle cerebral artery alterations in a rat chronic hypoperfusion model

    PubMed Central

    Márquez-Martín, Ana; Jiménez-Altayó, Francesc; Dantas, Ana P.; Caracuel, Laura; Planas, Anna M.

    2012-01-01

    Chronic cerebral hypoperfusion (CHP) induces microvascular changes that could contribute to the progression of vascular cognitive impairment and dementia in the aging brain. This study aimed to analyze the effects of CHP on structural, mechanical, and myogenic properties of the middle cerebral artery (MCA) after bilateral common carotid artery occlusion (BCCAO) in adult male Wistar rats. Sham animals underwent a similar surgical procedure without carotid artery (CA) ligation. After 15 days of occlusion, MCA and CA were dissected and MCA structural, mechanical, and myogenic properties were assessed by pressure myography. Collagen I/III expression was determined by immunofluorescence in MCA and CA and by Western blot in CA. mRNA levels for 1A1, 1A2, and 3A1 collagen subunits were quantified by quantitative real-time PCR in CA. Matrix metalloproteinase (MMP-1, MMP-2, MMP-9, and MMP-13) and hypoxia-inducible factor-1α (HIF-1α) protein expression were determined in CA by Western blot. BCCAO diminished cross-sectional area, wall thickness, and wall-to-lumen ratio. Nevertheless, whereas wall stress was increased, stiffness was not modified and myogenic response was diminished. Hypoperfusion triggered HIF-1α expression. Collagen I/III protein expression diminished in MCA and CA after BCCAO, despite increased mRNA levels for 1A1 and 3A1 collagen subunits. Therefore, the reduced collagen expression might be due to proteolytic degradation, since the expression of MMP-1 and MMP-9 increased in the CA. These data suggest that BCCAO induces hypotrophic remodeling by a mechanism that involves a reduction of collagen I/III in association with increased MMP-1 and MMP-9 and that decreases myogenic tone in major arteries supplying the brain. PMID:22096118

  14. The effects of sildenafil after chronic L-NAME administration in male rat sexual behavior.

    PubMed

    Ferraz, Marcia M D; Quintella, Suelen L; Parcial, André L N; Ferraz, Marcos R

    2016-01-01

    Ferraz MMD, Quintella SL, Parcial ALN, Ferraz MR. The effects of sildenafil citrate and L-NAME on male rat sexual behaviour. PHARMACOL BIOCHEM BEHAV. Erectile dysfunction (ED) affects up to 50% of men between 40 and 70years of age. Significant advances in the pharmacological treatment of ED occurred in recent years, most notably the introduction of the first oral selective phosphodiesterase type-5 inhibitor, sildenafil. This study investigated the effectiveness of chronic oral treatment with L-NAME in rats as an experimental model of erectile dysfunction to evaluate new pharmacological agents that affect the sexual response. The effects of chronic oral L-NAME treatment, separately or in combination with sildenafil, on the sexual behaviour of male rats were evaluated. Filtered water was used as a control. Acute administration of L-NAME did not alter the sexual response compared with control, but sildenafil administration facilitated sexual behaviour after acute and chronic administration. Chronic L-NAME treatment inhibited motivational and consummatory measures of male rat sexual behaviour. Sildenafil prevented the inhibitory effects of L-NAME. The present results confirm that chronic oral treatment with a nitric oxide synthase inhibitor may be a relevant peripheral ED model to evaluate the effects of drugs on erectile function of male rats. PMID:27132237

  15. Pharmacological TLR4 Inhibition Protects against Acute and Chronic Fat-Induced Insulin Resistance in Rats

    PubMed Central

    Zhang, Ning; Liang, Hanyu; Farese, Robert V.; Li, Ji

    2015-01-01

    Aims To evaluate whether pharmacological TLR4 inhibition protects against acute and chronic fat-induced insulin resistance in rats. Materials and Methods For the acute experiment, rats received a TLR4 inhibitor [TAK-242 or E5564 (2x5 mg/kg i.v. bolus)] or vehicle, and an 8-h Intralipid (20%, 8.5 mg/kg/min) or saline infusion, followed by a two-step hyperinsulinemic-euglycemic clamp. For the chronic experiment, rats were subcutaneously implanted with a slow-release pellet of TAK-242 (1.5 mg/d) or placebo. Rats then received a high fat diet (HFD) or a low fat control diet (LFD) for 10 weeks, followed by a two-step insulin clamp. Results Acute experiment; the lipid-induced reduction (18%) in insulin-stimulated glucose disposal (Rd) was attenuated by TAK-242 and E5564 (the effect of E5564 was more robust), suggesting improved peripheral insulin action. Insulin was able to suppress hepatic glucose production (HGP) in saline- but not lipid-treated rats. TAK-242, but not E5564, partially restored this effect, suggesting improved HGP. Chronic experiment; insulin-stimulated Rd was reduced ~30% by the HFD, but completely restored by TAK-242. Insulin could not suppress HGP in rats fed a HFD and TAK-242 had no effect on HGP. Conclusions Pharmacological TLR4 inhibition provides partial protection against acute and chronic fat-induced insulin resistance in vivo. PMID:26196892

  16. Effects of chronic ethanol administration on hepatic glycoprotein secretion in the rat

    SciTech Connect

    Sorrell, M.F.; Nauss, J.M.; Donohue, T.M. Jr.; Tuma, D.J.

    1983-03-01

    The effects of chronic ethanol feeding on protein and glycoprotein synthesis and secretion were studied in rat liver slices. Liver slices from rats fed ethanol for 4-5 wk showed a decreased ability to incorporate (/sup 14/C)glucosamine into medium trichloracetic acid-precipitable proteins when compared to the pair-fed controls; however, the labeling of hepatocellular glycoproteins was unaffected by chronic ethanol treatment. Immunoprecipitation of radiolabeled secretory (serum) glycoproteins with antiserum against rat serum proteins showed a similar marked inhibition in the appearance of glucosamine-labeled proteins in the medium of slices from ethanol-fed rats. Minimal effects, however, were noted in the labeling of intracellular secretory glycoproteins. Protein synthesis, as determined by measuring (/sup 14/C)leucine incorporation into medium and liver proteins, was decreased in liver slices from ethanol-fed rats as compared to the pair-fed controls. This was the case for both total proteins as well as immunoprecipitable secretory proteins, although the labeling of secretory proteins retained in the liver slices was reduced to a lesser extent than total radiolabeled hepatic proteins. When the terminal sugar, (/sup 14/C)fucose, was employed as a precursor in order to more closely focus on the final steps of hepatic glycoprotein secretion, liver slices obtained from chronic ethanol-fed rats exhibited impaired secretion of fucose-labeled proteins into the medium. When ethanol (5 or 10 mM) was added to the incubation medium containing liver slices from the ethanol-fed rats, the alterations in protein and glycoprotein synthesis and secretion caused by the chronic ethanol treatment were further potentiated. The results of this study indicate that liver slices prepared from chronic ethanol-fed rats exhibit both impaired synthesis and secretion of proteins and glycoproteins, and these defects are further potentiated by acute ethanol administration.

  17. Chronic studies evaluating the carcinogenicity of monomethylarsonic acid in rats and mice.

    PubMed

    Arnold, Lora L; Eldan, Michal; van Gemert, Marcia; Capen, Charles C; Cohen, Samuel M

    2003-08-28

    Monomethylarsonic acid (MMA) was administered in the diet of male and female Fischer F344 rats and B6C3F1 mice in 2-year feeding studies according to US EPA guidelines. Rats were treated with 50, 400, or 1300 ppm MMA and mice were treated with 10, 50, 200, or 400 ppm MMA based on preliminary short-term studies. The highest dose in the male and female rat groups was reduced to 1000 ppm during week 53 and then further reduced to 800 ppm during week 60 due to high mortality in the male rats. There was no treatment-related mortality in the mice. The primary target organ for MMA-induced toxicity in rats and mice was the large intestine. Toxicity was more severe in rats compared to mice and in male rats compared to female rats. The maximum tolerated dose for chronic dietary administration of MMA in rats and mice was assessed as 400 ppm, and the no effect level with regard to intestinal toxicity was assessed as 50 ppm for rats and female mice and 200 ppm for male mice. There were no treatment-related neoplastic effects detected in either the rat or the mouse.

  18. Drinking and blood pressure during sodium depletion or ANG II infusion in chronic cholestatic rats.

    PubMed

    Fitts, D A; Lane, J R; Starbuck, E M; Li, C P

    1999-01-01

    After a chronic ligation of the common bile duct (BDL), Long-Evans rats are hypotensive and have elevated saline intake during both sodium-depleted and nondepleted conditions. We tested whether BDL rats have exaggerated hypotension during sodium depletion or an elevated dipsogenic response to angiotensin II (ANG II) that might help to explain the saline intake. After 4 wk of BDL, rats were hypotensive at baseline and developed exaggerated hypotension during acute furosemide-induced diuresis. Without saline to drink, BDL rats increased water intake during depletion equal to sham-ligated rats. However, with saline solution available at 22 h after sodium depletion, the BDL rats drank more water and saline than did sham-ligated rats. This rapid intake temporarily increased their mean arterial pressure to equal that of sham-ligated rats. Intravenous infusion of ANG II induced equal drinking responses despite reduced pressor responses in the BDL rats relative to sham-ligated rats during both ad libitum and sodium-depleted conditions. Thus BDL rats have exaggerated hypotension during diuresis, and their hypotension is corrected by drinking an exaggerated volume of saline, but they do not have an increased drinking response to ANG II. PMID:9887174

  19. Chronic stress affects the expression of brain-derived neurotrophic factor in rat salivary glands.

    PubMed

    Saruta, Juri; Lee, Taeki; Shirasu, Masayoshi; Takahashi, Takeshi; Sato, Chikatoshi; Sato, Sadao; Tsukinoki, Keiichi

    2010-01-01

    Plasma brain-derived neurotrophic factor (BDNF) levels are associated with several neural disorders. Previously, we reported that BDNF is produced from salivary glands under acute immobilization stress. Additionally, salivary glands are the origin of plasma BDNF during stress; however, the association between the expression of BDNF by the salivary glands under chronic stress conditions is not known. In the present study, we investigated whether plasma BDNF levels in chronic stress depend on the salivary glands. Expression of BDNF mRNA and protein were identified in the submandibular glands when male rats were exposed to chronic restraint stress (12 h daily for 22 days). Chronic stress significantly increased plasma BDNF concentration, as well as adrenocorticotropic hormone and corticosterone levels, but was not altered under chronic stress in bilaterally sialoadenectomized rats. Since chronic stress increases plasma BDNF levels in the sialoadenectomized rat model, the plasma BDNF level was not dependent on BDNF from the salivary glands. Although the salivary glands were the source of plasma BDNF in acute stress conditions in our previous study, it seems that that the increased BDNF expression in the salivary glands in chronic stress does not contribute importantly to the increased circulating BDNF level. The increased plasma BDNF levels may play important roles in homeostasis under stress conditions.

  20. Case report of atypical hemolytic uremic syndrome with retinal arterial and venous occlusion treated with eculizumab

    PubMed Central

    Greenwood, Gregory T

    2015-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a rare disease caused by chronic, uncontrolled activation of the alternative complement pathway, leading to thrombotic microangiopathy. Renal impairment and progression to end-stage renal disease are common in untreated patients with aHUS, and extrarenal manifestations are being increasingly characterized in the literature. Ocular involvement remains rare in aHUS. This report describes a patient with aHUS with bilateral central retinal artery and vein occlusion, vitreous hemorrhage, and blindness in addition to renal impairment. The patient’s hematologic and renal parameters and ocular manifestation improved following initiation of eculizumab therapy. PMID:26508891

  1. Salt-induced changes in cardiac phosphoproteome in a rat model of chronic renal failure.

    PubMed

    Su, Zhengxiu; Zhu, Hongguo; Zhang, Menghuan; Wang, Liangliang; He, Hanchang; Jiang, Shaoling; Hou, Fan Fan; Li, Aiqing

    2014-01-01

    Heart damage is widely present in patients with chronic kidney disease. Salt diet is the most important environmental factor affecting development of chronic renal failure and cardiovascular diseases. The proteins involved in chronic kidney disease -induced heart damage, especially their posttranslational modifications, remain largely unknown to date. Sprague-Dawley rats underwent 5/6 nephrectomy (chronic renal failure model) or sham operation were treated for 2 weeks with a normal-(0.4% NaCl), or high-salt (4% NaCl) diet. We employed TiO2 enrichment, iTRAQ labeling and liquid-chromatography tandem mass spectrometry strategy for phosphoproteomic profiling of left ventricular free walls in these animals. A total of 1724 unique phosphopeptides representing 2551 non-redundant phosphorylation sites corresponding to 763 phosphoproteins were identified. During normal salt feeding, 89 (54%) phosphopeptides upregulated and 76 (46%) phosphopeptides downregulated in chronic renal failure rats relative to sham rats. In chronic renal failure rats, high salt intake induced upregulation of 84 (49%) phosphopeptides and downregulation of 88 (51%) phosphopeptides. Database searches revealed that most of the identified phospholproteins were important signaling molecules such as protein kinases, receptors and phosphatases. These phospholproteins were involved in energy metabolism, cell communication, cell differentiation, cell death and other biological processes. The Search Tool for the Retrieval of Interacting Genes analysis revealed functional links among 15 significantly regulated phosphoproteins in chronic renal failure rats compared to sham group, and 23 altered phosphoproteins induced by high salt intake. The altered phosphorylation levels of two proteins involved in heart damage, lamin A and phospholamban were validated. Expression of the downstream genes of these two proteins, desmin and SERCA2a, were also analyzed.

  2. Binding and biologic activity of glucagon in liver cell membranes of chronically hyperglucagonemic rats.

    PubMed

    Srikant, C B; Freeman, D; McCorkle, K; Unger, R H

    1977-11-10

    Glucagon binding by liver cell membranes was examined in rats with chronically elevated plasma levels of immunoreactive glucagon (IRG) resulting from insulin deficiency, starvation, or twice daily glucagon injections. The concentration of specific glucagon binding sites was significantly reduced in the three chronically hyperglucagonemic (IRG greater than 125 pg/ml) groups as compared with nondiabetic controls and insulin-treated diabetic control rats with only mild hyperglucagonemia. A reduction in glucagon binding sites did not occur with hyperglucagonemia of 12 h or less. Despite the reduced binding of glucagon in the three chronically hyperglucagonemic groups, the ability of glucagon to stimulate cAMP production was not reduced. It is concluded that while decreased glucagon binding occures in the forms of chronic hyperglucagonemia studied, it is not associated with a reduction in the ability of glucagon to stimulate cAMP production.

  3. Recessive mutations in DGKE cause atypical hemolytic-uremic syndrome

    PubMed Central

    Lemaire, Mathieu; Frémeaux-Bacchi, Véronique; Schaefer, Franz; Choi, Murim; Tang, Wai Ho; Le Quintrec, Moglie; Fakhouri, Fadi; Taque, Sophie; Nobili, François; Martinez, Frank; Ji, Weizhen; Overton, John D.; Mane, Shrikant M.; Nürnberg, Gudrun; Altmüller, Janine; Thiele, Holger; Morin, Denis; Deschenes, Georges; Baudouin, Véronique; Llanas, Brigitte; Collard, Laure; Majid, Mohammed A.; Simkova, Eva; Nürnberg, Peter; Rioux-Leclerc, Nathalie; Moeckel, Gilbert W.; Gubler, Marie Claire; Hwa, John; Loirat, Chantal; Lifton, Richard P.

    2013-01-01

    Pathologic thrombosis is a major cause of mortality. Hemolytic-uremic syndrome (HUS) features episodes of small vessel thrombosis resulting in microangiopathic hemolytic anemia, thrombocytopenia and renal failure1. Atypical HUS (aHUS) can result from genetic or autoimmune factors2 that lead to pathologic complement cascade activation3. By exome sequencing we identify recessive mutations in DGKE (diacylglycerol kinase epsilon) that co-segregate with aHUS in 9 unrelated kindreds, defining a distinctive Mendelian disease. Affected patients present with aHUS before age 1, have persistent hypertension, hematuria and proteinuria (sometimes nephrotic range), and develop chronic kidney disease with age. DGKE is found in endothelium, platelets, and podocytes. Arachidonic acid-containing diacylglycerols (DAG) activate protein kinase C, which promotes thrombosis. DGKE normally inactivates DAG signaling. We infer that loss of DGKE function results in a pro-thrombotic state. These findings identify a new mechanism of pathologic thrombosis and kidney failure and have immediate implications for treatment of aHUS patients. PMID:23542698

  4. Uremic pruritus. Clinical and experimental studies.

    PubMed

    Ståhle-Bäckdahl, M

    1989-01-01

    The aim of the study was to investigate clinical aspects of pruritus in maintenance hemodialysis patients and to evaluate factors of putative pathogenic importance. 60-65% of the patients in a maintenance hemodialysis program during a two-year period suffered from itching. Patients with pruritus tended to have been on dialysis treatment longer than those without pruritus (p = 0.05), otherwise there was no difference in clinical data or routine laboratory tests. Measurement of itch intensity continuously over one week in 28 patients using a computerized method showed that itching peaked at night after two days without dialysis, was relatively high during treatment and lowest during the day following dialysis. Our results suggest that the accumulation of pruritogens between dialysis sessions influences the intensity of itching. Most patients had "dry" skin. Recording of the stratum corneum water content by measurement of electrical capacitance, in 31 patients (19 with pruritus) and 12 controls, disclosed no significant difference between dialysis patients and controls, but a tendency that pruritic patients had a lower water content than the other subjects. In different body areas, there was a positive correlation in all groups between the clinical estimation of xerosis and hydration. Serum concentrations of parathyroid hormone (PTH) were significantly higher in dialysis patients with pruritus than in those without, but there was no correlation between the degree of symptoms and the PTH level. Indirect immunohistochemistry revealed no immunoreactivity for different parts of the PTH molecule in skin biopsies from uremic patients. Intradermal injections of PTH fragments did not evoke itching or other cutaneous reactions in patients or controls. Our results do not support PTH as a peripheral mediator of uremic itching. Flare reactions induced by intradermal histamine injections were significantly smaller in 26 dialysis patients (18 with pruritus) than in 9 healthy

  5. Chronic unpredictable stress regulates visceral adipocyte‐mediated glucose metabolism and inflammatory circuits in male rats

    PubMed Central

    Karagiannides, Iordanes; Golovatscka, Viktoriya; Bakirtzi, Kyriaki; Sideri, Aristea; Salas, Martha; Stavrakis, Dimitris; Polytarchou, Christos; Iliopoulos, Dimitrios; Pothoulakis, Charalabos; Bradesi, Sylvie

    2014-01-01

    Abstract Chronic psychological stress is a prominent risk factor involved in the pathogenesis of many complex diseases, including major depression, obesity, and type II diabetes. Visceral adipose tissue is a key endocrine organ involved in the regulation of insulin action and an important component in the development of insulin resistance. Here, we examined for the first time the changes on visceral adipose tissue physiology and on adipocyte‐associated insulin sensitivity and function after chronic unpredictable stress in rats. Male rats were subjected to chronic unpredictable stress for 35 days. Total body and visceral fat was measured. Cytokines and activated intracellular kinase levels were determined using high‐throughput multiplex assays. Adipocyte function was assessed via tritiated glucose uptake assay. Stressed rats showed no weight gain, and their fat/lean mass ratio increased dramatically compared to control animals. Stressed rats had significantly higher mesenteric fat content and epididymal fat pad weight and demonstrated reduced serum glucose clearing capacity following glucose challenge. Alterations in fat depot size were mainly due to changes in adipocyte numbers and not size. High‐throughput molecular screening in adipocytes isolated from stressed rats revealed activation of intracellular inflammatory, glucose metabolism, and MAPK networks compared to controls, as well as significantly reduced glucose uptake capacity in response to insulin stimulation. Our study identifies the adipocyte as a key regulator of the effects of chronic stress on insulin resistance, and glucose metabolism, with important ramifications in the pathophysiology of several stress‐related disease states. PMID:24819750

  6. Impaired acclimatization to chronic hypoxia in adult male and female rats following neonatal hypoxia.

    PubMed

    Lumbroso, Delphine; Joseph, Vincent

    2009-08-01

    We tested the hypothesis that neonatal exposure to hypoxia alters acclimatization to chronic hypoxia later in life. Rat pups were exposed to normobaric hypoxia (12% O(2); nHx group) in a sealed chamber, or to normoxia (21% O(2); nNx group) from the day before birth to postnatal day 10. The animals were then raised in normal conditions until reaching 12 wk of age. At this age, we assessed ventilatory and hematological acclimatization to chronic hypoxia by exposing male and female nHx and nNx rats for 2 wk to 10% O(2). Minute ventilation, metabolic rate, hypoxic ventilatory response, hematocrit, and hemoglobin levels were measured both before and after acclimatization. We also quantified right ventricular hypertrophy as an index of pulmonary hypertension both before and after acclimatization. There was a significant effect of neonatal hypoxia that decreases ventilatory response (relative to metabolic rate, VE/VCO(2)) to acute hypoxia before acclimatization in males but not in females. nHx rats had an impaired acclimatization to chronic hypoxia characterized by altered respiratory pattern and elevated hematocrit and hemoglobin levels after acclimatization, in both males and females. Right ventricular hypertrophy was present before and after acclimatization in nHx rats, indicating that neonatal hypoxia results in pulmonary hypertension in adults. We conclude that neonatal hypoxia impairs acclimatization to chronic hypoxia in adults and may be a factor contributing to the establishment of chronic mountain sickness in humans living at high altitude.

  7. Chronic variable stress exposure in male Wistar rats affects the first step of olfactory detection.

    PubMed

    Raynaud, Aurélien; Meunier, Nicolas; Acquistapace, Adrien; Bombail, Vincent

    2015-09-15

    For most animal species, olfaction plays a paramount role in their perception of the environment. Odours are initially detected in neurons located in the olfactory mucosa. This tissue is regulated by several physiological signals and can be altered in pathology. A number of clinical studies suggest an association between depressive disorders and olfactory sensory loss. In rodents, depressive-like states can be observed in models of chronic stress. We tested the hypothesis that olfactory function might be altered in a rat model of depression, induced by chronic variable stress (CVS). While CVS rats exhibited several symptoms consistent with chronic stress exposure and depressive-like states (increased sucrose intake in sucrose preference test, increased immobility in forced swim test, hyperlocomotion), their odorant responses recorded at the olfactory mucosa level by electro-olfactogram were decreased. In addition we observed increased apoptosis markers in the olfactory mucosa using Western Blot. Our data are consistent with reduced olfactory capacities in a laboratory rat model of chronic stress and depression, in agreement with human clinical data; this warrants further mechanistic studies. Furthermore, this works raises the possibility that altered olfactory function might be a confounding factor in the behavioural testing of chronically stressed or depressed rats.

  8. Effects of chronic normobaric hypoxic and hypercapnic exposure in rats: Prevention of experimental chronic mountain sickness by hypercapnia

    NASA Astrophysics Data System (ADS)

    Lincoln, B.; Bonkovsky, H. L.; Ou, Lo-Chang

    1987-09-01

    A syndrome of experimental chronic mountain sickness can be produced in the Hilltop strain of Sprague-Dawley rats by chronic hypobaric hypoxic exposure. This syndrome is characterized by polycythemia, plasma hemoglobinemia, pulmonary hypertension and right ventricular hypertrophy with eventual failure and death. It has generally been assumed that these changes are caused by chronic hypoxemia, not by hypobaric exposure per se. We have now confirmed this directly by showing that chronic normobaric hypoxic exposure (10.5% O2) produces similar hematologic and hemodynamic changes. Further, the addition of hypercapnic exposure to the hypoxic exposure blunted or prevented the effects of the hypoxic exposure probably by stimulating respiration, thus increasing the rate of oxygen delivery to the cells. Changes in the rate-controlling enzymes of hepatic heme metabolism, 5-aminolevulinate synthase and heme oxygenase, and in cytochrome(s) P-450, the major hepatic hemoprotein(s), were also measured in hypoxic and hypercapnic rats. Hypoxia decreased 5-aminolevulinate synthase and increased cytochrome(s) P-450, probably by increasing the size of a “regulatory” heme pool within hepatocytes. These changes were also prevented by the addition of hypercapnic to hypoxic exposure.

  9. Chronic selective serotonin reuptake inhibition modulates endothelial dysfunction and oxidative state in rat chronic mild stress model of depression.

    PubMed

    Matchkov, Vladimir V; Kravtsova, Violetta V; Wiborg, Ove; Aalkjaer, Christian; Bouzinova, Elena V

    2015-10-15

    Major depression is known to be associated with cardiovascular abnormalities, and oxidative stress has been suggested to play a role. We tested the hypothesis that antidepressant treatment reduces oxidative stress and endothelial dysfunctions in the chronic mild stress (CMS) model of depression in rats. Rats with >30% reduction in sucrose intake after 4 wk of CMS were defined in the study as CMS-susceptible and compared with unstressed controls. Sixteen CMS-susceptible and eight unstressed rats were treated during weeks 5 to 8 of the CMS protocol with escitalopram. Escitalopram-treated rats with >20% recovery in the sucrose consumption during the last 2 wk of treatment were defined as escitalopram responders. Rats that did not reach these criteria were defined as escitalopram nonresponders. In the open field test, escitalopram responders demonstrated anxiolytic effect of treatment. In mesenteric small arteries, escitalopram affected neither NO nor cyclooxygenase-1 (COX-1)-mediated vasodilation. Escitalopram potentiated endothelium-dependent hyperpolarization-like response, which was suppressed in the vehicle-treated CMS-susceptible rats and reduced COX-2-dependent relaxation, which was elevated in the vehicle-treated CMS-susceptible rats. Escitalopram did not affect blood pressure and heart rate, which were elevated in the vehicle-treated CMS-susceptible rats. Oxidative stress markers were changed in association with CMS in liver, heart, and brain. Escitalopram normalized oxidative stress markers in the majority of tissues. This study demonstrates that the antidepressant effect of escitalopram is associated with partial improvement of endothelial function in small arteries affecting COX-2 and endothelium-dependent hyperpolarization-like pathways. PMID:26269522

  10. Hypercaloric diet modulates effects of chronic stress: a behavioral and biometric study on rats.

    PubMed

    Oliveira, Carla de; Oliveira, Cleverson Moraes de; de Macedo, Isabel Cristina; Quevedo, Alexandre S; Filho, Paulo Ricardo Marques; Silva, Fernanda Ribeiro da; Vercelino, Rafael; de Souza, Izabel C Custodio; Caumo, Wolnei; Torres, Iraci L S

    2015-01-01

    Obesity is a chronic disease that has been associated with chronic stress and hypercaloric diet (HD) consumption. Increased ingestion of food containing sugar and fat ingredients (comfort food) is proposed to "compensate" chronic stress effects. However, this eating habit may increase body fat depositions leading to obesity. This study evaluated behavioral/physiological parameters seeking to establish whether there is an association between the effects of HD intake and stress, and to test the hypothesis that the development of anxious behavior and obesity during chronic stress periods depends on the type of diet. Sixty-day-old male Wistar rats (n = 100) were divided into four groups: standard chow, hypercaloric diet, chronic stress/standard chow and chronic stress/hypercaloric diet. Chronic stress was induced by restraint stress exposure for 1 h/day, for 80 d. At the end of this period, rat behavior was evaluated using open-field and plus-maze tests. The results showed that HD alone increased weight gain and adipose deposition in subcutaneous and mesenteric areas. However, stress reduced weight gain and adipose tissue in these areas. HD also increased naso-anal length and concurrent stress prevented this. Behavioral data indicated that stress increased anxiety-like behaviors and comfort food reduced these anxiogenic effects; locomotor activity increased in rats fed with HD. Furthermore, HD decreased corticosterone levels and stress increased adrenal weight. The data indicate that when rats are given HD and experience chronic stress this association reduces the pro-obesogenic effects of HD, and decreases adrenocortical activity.

  11. Chronic variable stress improves glucose tolerance in rats with sucrose-induced prediabetes

    PubMed Central

    Packard, Amy E. B.; Ghosal, Sriparna; Herman, James P.; Woods, Stephen C.; Ulrich-Lai, Yvonne M.

    2014-01-01

    The incidence of type-2 diabetes (T2D) and the burden it places on individuals, as well as society as a whole, compels research into the causes, factors and progression of this disease. Epidemiological studies suggest that chronic stress exposure may contribute to the development and progression of T2D in human patients. To address the interaction between chronic stress and the progression of T2D, we developed a dietary model of the prediabetic state in rats utilizing unlimited access to 30% sucrose solution (in addition to unlimited access to normal chow and water), which led to impaired glucose tolerance despite elevated insulin levels. We then investigated the effects of a chronic variable stress paradigm (CVS; twice daily exposure to an unpredictable stressor for 2 weeks) on metabolic outcomes in this prediabetic model. Chronic stress improved glucose tolerance in prediabetic rats following a glucose challenge. Importantly, pair-fed control groups revealed that the beneficial effect of chronic stress did not result from the decreased food intake or body weight gain that occurred during chronic stress. The present work suggests that chronic stress in rodents can ameliorate the progression of diet-induced prediabetic disease independent of chronic stress-induced decreases in food intake and body weight. PMID:25001967

  12. Chronic behavioral and cognitive deficits in a rat survival model of paraoxon toxicity.

    PubMed

    Deshpande, Laxmikant S; Phillips, Kristin; Huang, Beverly; DeLorenzo, Robert J

    2014-09-01

    Organophosphate (OP) compounds, including paraoxon (POX), are similar to nerve agents such as sarin. There is a growing concern that OP agents could be weaponized to cause mass civilian causalities. We have developed a rodent survival model of POX toxicity that is being used to evaluate chronic morbidity and to screen for medical countermeasures against severe OP exposure. It is well known that the survivors of nerve gas and chronic OP exposure exhibit neurobehavioral deficits such as mood changes, depression, and memory impairments. In this study we investigated whether animals surviving severe POX exposure exhibited long-term neurological impairments. POX exposure produced overt signs of cholinergic toxicity. Rats were rescued using an optimized atropine, 2-PAM and diazepam therapy. Surviving rats were studied using established behavioral assays for identifying symptoms of depression and memory impairment 3-months after POX exposure. In the forced swim test, POX rats exhibited increased immobility time indicative of a despair-like state. In the sucrose preference test, POX rats consumed significantly less sucrose water indicating anhedonia-like condition. POX rats also displayed increased anxiety as characterized by significantly lower performance in the open arm of the elevated plus maze. Further, when tested with a novel object recognition paradigm, POX rats exhibited a negative discrimination ratio indicative of impaired recognition memory. The results indicate that this model of survival from severe POX exposure can be employed to study some of the molecular bases for OP-induced chronic behavioral and cognitive comorbidities and develop therapies for their treatment.

  13. Simultaneous impairment of passive avoidance learning and nociception in rats following chronic swim stress

    PubMed Central

    Nazeri, Masoud; Shabani, Mohammad; Parsania, Shahrnaz; Golchin, Leila; Razavinasab, Moazamehosadat; Abareghi, Fatemeh; Kermani, Moein

    2016-01-01

    Background: Stress can alter response to nociception. Under certain circumstances stress enhances nociception, a phenomenon which is called stress-induced hyperalgesia (SIH). While nociception has been studied in this paradigm, possible alterations occurring in passive avoidance (PA) learning after exposing rats to this type of stress has not been studied before. Materials and Methods: In the current study, we evaluated the effect of chronic swim stress (FS) or sham swim (SS) on nociception in both spinal (tail-flick) and supraspinal (53.5°C hot-pate) levels. Furthermore, PA task was performed to see whether chronic swim stress changes PA learning or not. Mobility of rats and anxiety-like behavior were assessed using open-field test (OFT). Results: Supraspinal pain response was altered by swim stress (hot-plate test). PA learning was impaired by swim stress, rats in SS group did not show such impairments. Rats in the FS group showed increased mobility (rearing, velocity, total distant moved (TDM) and decreased anxiety-like behavior (time spent in center and grooming) compared to SS rats. Conclusions: This study demonstrated the simultaneous impairment of PA and nociception under chronic swim stress, whether this is simply a co-occurrence or not is of special interest. This finding may implicate a possible role for limbic structures, though this hypothesis should be studied by experimental lesions in different areas of rat brain to assess their possible role in the pathophysiology of SIH. PMID:27308265

  14. Rat Model of Chronic Recurrent Airway Obstructions to Study the Sleep Apnea Syndrome

    PubMed Central

    Farré, Ramon; Nácher, Maria; Serrano-Mollar, Anna; Gáldiz, Juan B; Alvarez, Francisco J; Navajas, Daniel; Montserrat, Josep M.

    2007-01-01

    Study Objectives: To implement a chronic rat model of recurrent airway obstructions to study the obstructive sleep apnea (OSA) syndrome. Design: Prospective controlled animal study. Setting: University laboratory. Patients or Participants: 24 male Sprague-Dawley rats (250–300 g). Interventions: The rats were placed in a setup consisting of a body chamber and a head chamber separated by a neck collar specially designed to apply recurrent airway obstructions with OSA patterns. Rats in the Obstruction group (n=8) were subjected to 5-s obstructions at a rate of 60 per hour, 6 h/day during 4 weeks. Sham rats (n=8) were placed in the setup but no obstructions were applied. Naive rats (n=8) were subjected to no intervention. Measurements and Results: Breathing flow, pressure, CO2 air concentration, and SpO2 showed that the model mimicked OSA respiratory events (obstructive apneas, increased respiratory efforts, and oxygen saturation dips). Animal stress, assessed by body weight and plasma corticosterone, was not significantly different across Obstruction and Sham groups. This supports the concept that this novel model does not introduce a significant burden of stress in the rat after acclimatization to the chamber. Thromboxane-B2/6-keto-Prostaglandin-F1α ratio in plasma, which is an index of vasoconstriction, was significantly increased in the rats subjected to obstructions. Conclusions: The designed animal model of chronic recurrent airway obstructions is feasible and potentially useful to study the mechanisms involved in the cardiovascular consequences of OSA. Citation: Farré R; Nácher M; Serrano-Mollar A et al. Rat model of chronic recurrent airway obstructions to study the sleep apnea syndrome. SLEEP 2007;30(7):930-933. PMID:17682665

  15. Female cotton rats (Sigmodon hispidus) develop chronic anemia with renal inflammation and cystic changes.

    PubMed

    Ichii, Osamu; Nakamura, Teppei; Irie, Takao; Kouguchi, Hirokazu; Nakamura, Daisuke; Nakamura, Saori; Sato, Shinobu; Yokoyama, Keisuke; Horino, Taro; Sunden, Yuji; Elewa, Yaser Hosny Ali; Kon, Yasuhiro

    2016-09-01

    The cotton rat (Sigmodon hispidus) is a laboratory rodent that has been used for studies on human infectious diseases. In the present study, we observed that female cotton rats, not the male cotton rats, developed chronic anemia characterized by reduced red blood cell, hemoglobin, and hematocrit levels from 5 to 9 months of age without any changes in the mean corpuscular hemoglobin and volume levels. In peripheral blood, the reticulocyte count did not increase in response to anemia in female cotton rats, and no extramedullary hematopoiesis was observed in the liver or spleen. Further, the serum levels of urea nitrogen and creatinine increased from 5 to 9 months of age in female cotton rats compared to male cotton rats, and these increases became more prominent from 10 months of age onward, indicating chronic kidney disease. Histopathologically, female cotton rats manifested tubulointerstitial lesions characterized by the infiltration of mononuclear cells, including plasma cells and CD3(+) T-cells, as well as the dilation of calbindin-D28k(+) distal tubules from 5 to 9 months of age. The severity of these lesions progressed from 10 months of age onward, and renal fibrotic features and numerous tubular cysts appeared without any obvious glomerular lesions. A significant decrease in the erythropoietin protein levels was observed in the kidney of aged female cotton rats, and significant correlations were detected between anemia and tubulointerstitial damage. These results suggest that aged female cotton rats chronically develop renal anemia, and this rodent may serve as a novel model to elucidate its pathogenesis. PMID:27099161

  16. Chronic inhalation exposure of rats to vapors of nitroethane.

    PubMed

    Griffin, T B; Stein, A A; Coulston, F

    1988-08-01

    Male and female Long-Evans rats were exposed in inhalation chambers to vapors of nitroethane at concentrations of 100 or 200 ppm, 7 hr per day, 5 days per week for 2 years. During the study, general observations were made daily and body weights were obtained weekly for the first 6 months of the study and biweekly thereafter. Any rats that were found dead or sacrificed moribund during the 2-year exposure phase of the study were given a thorough gross examination and tissues were retained for microscopic examination. After 2 years of inhalation of nitroethane, all surviving rats were sacrificed and subjected to the same thorough gross examination. Blood samples were obtained from representative groups of animals for hematology and serum chemistry studies. All rats were examined histopathologically. Exposure of the rats to nitroethane had no pharmacologic effects nor were there any effects on mortality of rats of either sex at either level of exposure. Throughout most of the investigation, body weights of both sexes of both exposed groups were slightly less than those of respective controls, but lack of a well-defined dose-response relationship suggested the involvement of factors other than just exposure to nitroethane. There were no effects of exposure to nitroethane on hematology nor were there any biologically significant effects of exposure to nitroethane on clinical chemistry or on organ weights. No significant nonneoplastic or neoplastic pathology was found as a consequence of exposure of the rats to nitroethane. PMID:3181065

  17. Maximal conservative therapy of calcific uremic ateriolopathy.

    PubMed

    Van Noten, Charlotte; Janssen van Doorn, Karin; Vermander, Evert; Vlayen, Sonja; Verpooten, Gert A; Couttenye, Marie-Madeleine

    2012-07-01

    We present the case of a 61-year- old female patient in long-term hemodialysis who developed calcific uremic arteriolopathy (CUA) upon administration of the oral calcimimetic agent cinacalcet for treatment of secondary hyperparathyroidism. In May 2009, the baseline serum values were parathormone (PTH) 310 pg/ml, calcium 9.1 mg/dl and phosphorous 6.9 mg/dl. Necrotic wounds in the suprapubic fat tissue were successfully treated first, by correcting the calcium phosphorous product; second, through treatment with sodium thiosulfate and third, through intensive wound care with hyperbaric oxygen therapy and vacuum-assisted closure therapy, with no need for parathyroidectomy. Multiple factors have been described to play a role in the development of CUA. Based on the findings of this case, the treatment of CUA should be aimed at correcting different causes simultaneously.

  18. Prepubertal chronic stress and ketamine administration to rats as a neurodevelopmental model of schizophrenia symptomatology.

    PubMed

    Ram, Edward; Raphaeli, Shani; Avital, Avi

    2013-11-01

    Increased vulnerability to psychiatric disorders, such as schizophrenia, has been associated with higher levels of stress. In the early development of the central nervous system, changes in function of glutamatergic N-Methyl-D-aspartate (NMDA) receptors can possibly result in the development of psychosis, cognitive impairment and emotional dysfunction in adulthood. Thus, in this study we examined the behavioural consequences of the exposure of male rats to chronic stress (postnatal days 30-60) and ketamine administration (postnatal days 41-45); both during a sensitive developmental time window. We found that the locomotor activity of both ketamine and ketamine+chronic stress groups was significantly higher compared with that of the control rats. In contrast, the locomotor activity of the chronic stress group was significantly lower compared with all other groups. Examining anhedonia in the sucrose preference test we found a significantly decreased sucrose intake in both ketamine+chronic stress and the chronic stress groups compared with the control rats. No significant differences were observed in sucrose intake between the control and the ketamine group. The object recognition test revealed that the attention to the novel object was significantly impaired in the ketamine+chronic stress group. Similarly, the ketamine+chronic stress group showed the poorest learning ability in the eight-arm radial maze, starting on the 8th day. Finally, throughout the different pre-pulse intensities, the ketamine+chronic stress group showed impaired PPI compared with all other groups. The results indicate that the combination of prepubertal onset of chronic stress and ketamine may serve as a valid novel animal model for schizophrenia-like symptoms. PMID:23915719

  19. Prepubertal chronic stress and ketamine administration to rats as a neurodevelopmental model of schizophrenia symptomatology.

    PubMed

    Ram, Edward; Raphaeli, Shani; Avital, Avi

    2013-11-01

    Increased vulnerability to psychiatric disorders, such as schizophrenia, has been associated with higher levels of stress. In the early development of the central nervous system, changes in function of glutamatergic N-Methyl-D-aspartate (NMDA) receptors can possibly result in the development of psychosis, cognitive impairment and emotional dysfunction in adulthood. Thus, in this study we examined the behavioural consequences of the exposure of male rats to chronic stress (postnatal days 30-60) and ketamine administration (postnatal days 41-45); both during a sensitive developmental time window. We found that the locomotor activity of both ketamine and ketamine+chronic stress groups was significantly higher compared with that of the control rats. In contrast, the locomotor activity of the chronic stress group was significantly lower compared with all other groups. Examining anhedonia in the sucrose preference test we found a significantly decreased sucrose intake in both ketamine+chronic stress and the chronic stress groups compared with the control rats. No significant differences were observed in sucrose intake between the control and the ketamine group. The object recognition test revealed that the attention to the novel object was significantly impaired in the ketamine+chronic stress group. Similarly, the ketamine+chronic stress group showed the poorest learning ability in the eight-arm radial maze, starting on the 8th day. Finally, throughout the different pre-pulse intensities, the ketamine+chronic stress group showed impaired PPI compared with all other groups. The results indicate that the combination of prepubertal onset of chronic stress and ketamine may serve as a valid novel animal model for schizophrenia-like symptoms.

  20. Chronic stress sensitizes rats to pancreatitis induced by cerulein: Role of TNF-α

    PubMed Central

    Binker, Marcelo G; Binker-Cosen, Andres A; Richards, Daniel; Gaisano, Herbert Y; de Cosen, Rodica H; Cosen-Binker, Laura I

    2010-01-01

    AIM: To investigate chronic stress as a susceptibility factor for developing pancreatitis, as well as tumor necrosis factor-α (TNF-α) as a putative sensitizer. METHODS: Rat pancreatic acini were used to analyze the influence of TNF-α on submaximal (50 pmol/L) cholecystokinin (CCK) stimulation. Chronic restraint (4 h every day for 21 d) was used to evaluate the effects of submaximal (0.2 μg/kg per hour) cerulein stimulation on chronically stressed rats. RESULTS: In vitro exposure of pancreatic acini to TNF-α disorganized the actin cytoskeleton. This was further increased by TNF-α/CCK treatment, which additionally reduced amylase secretion, and increased trypsin and nuclear factor-κB activities in a protein-kinase-C δ and ε-dependent manner. TNF-α/CCK also enhanced caspases’ activity and lactate dehydrogenase release, induced ATP loss, and augmented the ADP/ATP ratio. In vivo, rats under chronic restraint exhibited elevated serum and pancreatic TNF-α levels. Serum, pancreatic, and lung inflammatory parameters, as well as caspases’activity in pancreatic and lung tissue, were substantially enhanced in stressed/cerulein-treated rats, which also experienced tissues’ ATP loss and greater ADP/ATP ratios. Histological examination revealed that stressed/cerulein-treated animals developed abundant pancreatic and lung edema, hemorrhage and leukocyte infiltrate, and pancreatic necrosis. Pancreatitis severity was greatly decreased by treating animals with an anti-TNF-α-antibody, which diminished all inflammatory parameters, histopathological scores, and apoptotic/necrotic markers in stressed/cerulein-treated rats. CONCLUSION: In rats, chronic stress increases susceptibility for developing pancreatitis, which involves TNF-α sensitization of pancreatic acinar cells to undergo injury by physiological cerulein stimulation. PMID:21105189

  1. Ketamine treatment reverses behavioral and physiological alterations induced by chronic mild stress in rats.

    PubMed

    Garcia, Lêda S B; Comim, Clarissa M; Valvassori, Samira S; Réus, Gislaine Z; Stertz, Laura; Kapczinski, Flávio; Gavioli, Elaine C; Quevedo, João

    2009-04-30

    Several studies have supported the idea that ionotropic glutamate N-methyl-d-aspartate receptor (NMDA) is an important player in the etiology of psychopathologies, such as anxiety disorders and major depression. Additionally, studies have shown that ketamine induces antidepressant effects in humans as well as in rodents subjected to animal models of depression. In this context, the present study was aimed to evaluate behavioral and physiological effects of acute and chronic administration of ketamine, a NMDA receptor antagonist, in rats exposed to chronic mild stress (CMS). After 40 days of CMS, rats were treated with ketamine (15 mg/kg) and sweet food consumption, body and adrenal gland weight, corticosterone and adrenocorticotropic (ACTH) hormone levels, and hippocampal BDNF protein levels were assessed. Our findings demonstrated that CMS evoked anhedonia, induced hypertrophy of adrenal gland, impaired gain of body weight and increased corticosterone and ACTH circulating levels in rats. Acute and chronic treatment with ketamine reversed the increase in adrenal gland weight, promoted regain of body weight, and normalized corticosterone and ACTH circulating levels. Repeated, but not acute, administration of ketamine reversed anhedonia-like behavior, although the treatment with ketamine per se increased sweet food consumption in non-stressed rats. Finally, acute and chronic ketamine treatment did not alter hippocampal BDNF protein levels in stressed rats. In conclusion, these findings support the idea of a putative role of NMDA receptors in mood-related symptoms, and rapid and robust effects of ketamine in reverting mainly physiological alterations induced by chronic mild stressful situations in rats.

  2. Histological effects of chronic consumption of soda pop drinks on kidney of adult Wister rats

    PubMed Central

    Adjene, Josiah Obaghwarhievwo; Ezeoke, Joseph Chigozie; Nwose, Ezekiel Uba

    2010-01-01

    Background: Health concerns over soda pop drinks have been severally report. However, histological perspectives are not very common. Aim: The objective of this study is to investigate histological effect of chronic consumption of soda pop drinks on the kidney of adult Wistar rats. Materials and methods: The rats of both sexes (n = 24), with average weight of 200g were randomly assigned into two treatment (A & B) (n=16) and Control (c) (n=8) groups. The rats in the treatment group (A) received a brand of soda pop drink on a daily basis for thirty days. The rats in treatment group (B) received another brand of soda drink, while the control group (C) received equal amount of water for the same period. The rats were given the drinks as well as feeds liberally for thirty days, and sacrificed by cervical dislocation on the thirty-first day of the experiment. The kidney was carefully dissected out and quickly fixed in 10% formal saline for histological study. Results: The findings indicate that rats in the treated groups (A&B) showed some varying degree of distortion and disruption of the renal structure. There are observable diffuse signs of glomerulonephritis with some congestion and tubular necrosis as compared to the control group. Conclusion: Chronic consumption of soda pop drinks may affect the microanatomy of the kidney of adult Wistar rats. Further study aimed at corroborating these observations in humans is warranted. PMID:22574291

  3. Histological effects of chronic administration of Phyllanthus amarus on the kidney of adult Wistar rat

    PubMed Central

    Adjene, Josiah Obaghwarhieywo; Nwose, Ezekiel Uba

    2010-01-01

    Background: Phyllanthus amarus is commonly used for treatment such as in gastro, urogenital diseases and infection. However, it is speculated to have some toxic effects such as renal tubular damage. Aims: This study was to investigate the histological effects of chronic administration of the herb on kidney of adult Wistar rats. Material and Methods: Rats of both sexes (n = 24), with average weight of 200g were randomly assigned into two treatments (A and B) and control (C) groups of 8 rats each. Rats in treatment groups (A) and (B) respectively received daily administration of 400mg and 800mg of aqueous Phyllanthus amarus, per 70kg body weight for 30days through the orogastric tube. The control group received distilled water through the same route. All rats were fed with grower's mash and given water liberally. The rats were sacrificed by cervical dislocation on the thirty-first day of the experiment and the kidneys were carefully dissected out and quickly fixed in 10% formal saline for histological study. Results: The observations indicate that rats in the treated groups showed some varying degree of distortion and disruption in microanatomy of the kidney including interstitial oedema and tubular necrosis, when compared to the control section. Conclusion: This report provides further evidence that medicinal use of Phyllanthus amarus has a potential adverse effect. This warrants further studies to establish or rule out any untoward side-effect of chronic renal dysfunctions. PMID:22624139

  4. Tianeptine exerts neuroprotective effects in the brain tissue of rats exposed to the chronic stress model.

    PubMed

    Della, Franciela P; Abelaira, Helena M; Réus, Gislaine Z; Antunes, Altamir R; Dos Santos, Maria Augusta B; Zappelinni, Giovanni; Steckert, Amanda V; Vuolo, Francieli; Galant, Letícia S; Dal-Pizzol, Felipe; Kapczinski, Flávio; Quevedo, João

    2012-12-01

    Animal models of chronic stress represent valuable tools by which to investigate the behavioral, endocrine and neurobiological changes underlying stress-related psychopathologies, such as major depression, and the efficacy of antidepressant therapies. The present study was aimed at investigating the neurochemical effects of the antidepressant tianeptine in rats exposed to the chronic stress model. To this aim, rats were subjected to 40days of chronic unpredictable stressful stimuli, after which the animals received saline or tianeptine (15mg/kg) once a day for 7days. Additionally, IL-6, IL-1, TNF-α levels and oxidative stress parameters were assessed in the prefrontal cortex (PFC), hippocampus (HPC), amygdala (AMY) and nucleus accumbens (NAc) in all of the experimental groups studied. The results indicated that chronic mild stress and tianeptine did not exercise any effects on cytokines in all of the structures studied; in the PFC and AMY thiobarbituric acid reactive substances (TBARS) levels were decreased in control rats treated with tianeptine in the HPC; superoxide dismutase (SOD) activity was found to have decreased in stressed rats treated with saline in the PFC, HPC, AMY and NAc, and tianeptine reversed this effect; catalase (CAT) activity was found to have decreased in the PFC, HPC and NAc of stressed rats treated with saline, but was shown to have increased in stressed rats treated with tianeptine, and tianeptine also reversed the decreases in CAT activity in stressed rats treated with saline, suggesting that tianeptine exerted antioxidant activity. In conclusion, the present findings open new vistas on the pharmacological activity of tianeptine, in particular, concerning its ability to attenuate oxidative stress.

  5. Different adaptation of the motor activity rhythm to chronic phase shifts between adolescent and adult rats.

    PubMed

    Albert, Nerea; da Silva, Crhistiane; Díez-Noguera, Antoni; Cambras, Trinitat

    2013-09-01

    Chronic phase shifts is a common feature in modern societies, which may induce sleep alterations and other health problems. The effects of phase shift on the circadian rhythms have been described to be more pronounced in old than in young animals. However, few works address the effects of chronic phase shifts during adolescence. Here we tested the development of the motor activity circadian rhythm of young rats under chronic phase shifts, which consisted on 6-h advances (A), 6h delays (D) or 6h advances and delays alternated every 5 days (AD) during the first 60 days after weaning. Moreover, the rhythmic pattern was compared to that of adult rats under the same lighting conditions. Results indicate that adolescent rats, independently on the lighting environment, developed a clear circadian rhythm, whose amplitude increased the first 50 days after weaning and showed a more stable circadian rhythm than adults under the same lighting conditions. In the case of A and AD groups, circadian disruption was observed only in adult rats. In all groups, the offset of activity correlated with light pattern better than the onset, and this correlation was always higher in the case of the rhythm of the pubertal rats. When AD groups were transferred to constant darkness, the group submitted to this condition during adolescence showed shorter period than that submitted in their adulthood. In conclusion, differently from adult rats, adolescent rats submitted to chronic phase shifts did not show circadian disruption and developed a single circadian rhythm, suggesting permanent changes in the circadian system.

  6. Different adaptation of the motor activity rhythm to chronic phase shifts between adolescent and adult rats.

    PubMed

    Albert, Nerea; da Silva, Crhistiane; Díez-Noguera, Antoni; Cambras, Trinitat

    2013-09-01

    Chronic phase shifts is a common feature in modern societies, which may induce sleep alterations and other health problems. The effects of phase shift on the circadian rhythms have been described to be more pronounced in old than in young animals. However, few works address the effects of chronic phase shifts during adolescence. Here we tested the development of the motor activity circadian rhythm of young rats under chronic phase shifts, which consisted on 6-h advances (A), 6h delays (D) or 6h advances and delays alternated every 5 days (AD) during the first 60 days after weaning. Moreover, the rhythmic pattern was compared to that of adult rats under the same lighting conditions. Results indicate that adolescent rats, independently on the lighting environment, developed a clear circadian rhythm, whose amplitude increased the first 50 days after weaning and showed a more stable circadian rhythm than adults under the same lighting conditions. In the case of A and AD groups, circadian disruption was observed only in adult rats. In all groups, the offset of activity correlated with light pattern better than the onset, and this correlation was always higher in the case of the rhythm of the pubertal rats. When AD groups were transferred to constant darkness, the group submitted to this condition during adolescence showed shorter period than that submitted in their adulthood. In conclusion, differently from adult rats, adolescent rats submitted to chronic phase shifts did not show circadian disruption and developed a single circadian rhythm, suggesting permanent changes in the circadian system. PMID:23792134

  7. Protection of Chinese herbs against adenine-induced chronic renal failure in rats.

    PubMed

    Tong, Yanqing; Han, Bing; Guo, Hongyang; Liu, Yanru

    2010-01-01

    The aim of the study is to evaluate the efficacy of Chinese herbs (Angelica sinensis, Ligusticum wallichii, Salvia miltiorrhiza, Rhizoma dioscoreae, Rhodiola crenilata, Astragalus membranaceus and Angelica sinensis) on adenine-induced chronic renal failure in rats. 30 age-matched male Wistar rats were divided into three groups. Rats in group A (n = 10), B (n = 10) and C (n = 10) were fed a standard laboratory chow and allowed tap water ad libitum. In group B and C, renal failure was induced by the administration of a diet containing 0.75% adenine for 28 days which began at day 0. Rats in group C were given Chinese herbs (40 ml/kg with drug concentration 1.75 g/ml) beginning at day 0. Urine albumin, blood urea nitrogen (BUN) and creatinine were determined at days 0, 14 and 28. At day 28, the animals were killed and their kidneys removed for light microscope evaluation. Body weight in Group B decreased more significantly than that in Group C (p = 0.032) at day 28. The rats in group B demonstrated more severe proteinuria and higher Serum creatinine and BUN levels than group C at day 14 and day 28 (P < 0.05, 0.01). All rats given adenine developed marked structural renal damage involving the tubule and interstitium. The values were much less severe in group C than those in group B. In adenine-induced chronic renal failure rats, the protective effects of these Chinese herbs were of a significant nature. Our results do support the notion that these Chinese herbs are useful in deferring the advance of chronic renal failure. We recommend Chinese herbs as a beneficial treatment for pre-end stage chronic renal failure.

  8. Tianeptine exerts neuroprotective effects in the brain tissue of rats exposed to the chronic stress model.

    PubMed

    Della, Franciela P; Abelaira, Helena M; Réus, Gislaine Z; Antunes, Altamir R; Dos Santos, Maria Augusta B; Zappelinni, Giovanni; Steckert, Amanda V; Vuolo, Francieli; Galant, Letícia S; Dal-Pizzol, Felipe; Kapczinski, Flávio; Quevedo, João

    2012-12-01

    Animal models of chronic stress represent valuable tools by which to investigate the behavioral, endocrine and neurobiological changes underlying stress-related psychopathologies, such as major depression, and the efficacy of antidepressant therapies. The present study was aimed at investigating the neurochemical effects of the antidepressant tianeptine in rats exposed to the chronic stress model. To this aim, rats were subjected to 40days of chronic unpredictable stressful stimuli, after which the animals received saline or tianeptine (15mg/kg) once a day for 7days. Additionally, IL-6, IL-1, TNF-α levels and oxidative stress parameters were assessed in the prefrontal cortex (PFC), hippocampus (HPC), amygdala (AMY) and nucleus accumbens (NAc) in all of the experimental groups studied. The results indicated that chronic mild stress and tianeptine did not exercise any effects on cytokines in all of the structures studied; in the PFC and AMY thiobarbituric acid reactive substances (TBARS) levels were decreased in control rats treated with tianeptine in the HPC; superoxide dismutase (SOD) activity was found to have decreased in stressed rats treated with saline in the PFC, HPC, AMY and NAc, and tianeptine reversed this effect; catalase (CAT) activity was found to have decreased in the PFC, HPC and NAc of stressed rats treated with saline, but was shown to have increased in stressed rats treated with tianeptine, and tianeptine also reversed the decreases in CAT activity in stressed rats treated with saline, suggesting that tianeptine exerted antioxidant activity. In conclusion, the present findings open new vistas on the pharmacological activity of tianeptine, in particular, concerning its ability to attenuate oxidative stress. PMID:23036485

  9. Protective effect of Xingnaojia formulation on rats with brain and liver damage caused by chronic alcoholism

    PubMed Central

    LI, SHUANG; WANG, SU; GUO, ZHI-GANG; HUANG, NING; ZHAO, FAN-RONG; ZHU, MO-LI; MA, LI-JUAN; LIANG, JIN-YING; ZHANG, YU-LIN; HUANG, ZHONG-LIN; WAN, GUANG-RUI

    2015-01-01

    The aim of this study was to observe the effect of a formulation of traditional Chinese medicine extracts known as Xingnaojia (XNJ) on the liver function, learning ability and memory of rats with chronic alcoholism and to verify the mechanism by which it protects the brain and liver. A rat model of chronic alcoholism was used in the study. The spatial learning ability and memory of the rats were tested. The rats were then sacrificed and their brains and hepatic tissues were isolated. The activity of superoxide dismutase (SOD) and levels of glutamate (Glu), N-methyl D-aspartate receptor subtype 2B (NR2B), cyclin-dependent kinase 5 (CDK5) and cannabinoid receptor 1 (CB1) in the hippocampus were analyzed. The ultrastructure of the hepatic tissue was observed by electron microscopy. In addition, the activities of alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in serum were tested and the levels of low-density lipoprotein (LDL), high-density lipoprotein (HDL), triglycerides (TG) and total cholesterol (TCHOL) were analyzed. XNJ enhanced the learning and memory of rats with chronic alcoholism. Treatment with XNJ increased the activity of SOD, and decreased the expression levels of NR2B mRNA and NR2B, CB1 and CDK5 proteins in the brain tissues compared with those in the model rats. It also increased the activity of ALDH in the serum and liver, decreased the serum levels of LDL, TG and TCHOL and increased the serum level of HDL. These results indicate that XNJ exhibited a protective effect against brain and liver damage in rats with chronic alcoholism. PMID:26640531

  10. Development of chronic allograft rejection and arterial hypertension in Brown Norway rats after renal transplantation.

    PubMed

    Vaskonen, T; Mervaala, E; Nevala, R; Soots, A; Krogerus, L; Lähteenmäki, T; Karppanen, H; Vapaatalo, H; Ahonen, J

    2000-01-01

    The cardiovascular and renal pathophysiology associated with chronic renal allograft rejection under triple drug immunosuppressive treatment was studied using a recently developed model (Brown Norway (BN) rats) in a 6-week experiment. Renal transplantation was performed to 10-week-old rats in a rat strain combination of Dark Agouti (DA) --> BN. The right kidney was removed from another group of BN rats (uninephrectomized). A triple drug treatment comprising cyclosporine (10 mg/kg subcutaneously, s.c.), azathioprine (2 mg/kg s.c.) and methylprednisolone (1.6 mg/kg s.c.) was given to each rat daily for 6 weeks. A control group underwent no operations nor drug treatment. After the transplantation, the systolic blood pressure in this group was increased from 116 +/- 2 to 166 +/- 2 mmHg, while in the uninephrectomized group the rise was from 115 +/- 4 to 146 +/- 4 mmHg, and no change was observed in the blood pressures of the control group. The vascular relaxation responses of mesenteric arterial rings in vitro to acetylcholine were inhibited in both the transplantation group and the uninephrectomized group as compared with the control group, but few significant differences were found in the contraction responses to noradrenaline and potassium chloride. Graft histology was examined after 6 weeks, quantified by using the chronic allograft damage index (CADI). Changes specific to a chronic rejection reaction were observed in the allografts (CADI mean 6.0) but no injuries were seen in the rats' own kidneys (CADI mean 1.2). Our findings show that allograft rejection in BN rats after renal transplantation is associated with the development of arterial hypertension. The combination of cyclosporine, methylprednisolone and azathioprine also rises blood pressure in uninephrectomized BN rats. The hypertensive effects of the drug treatment and graft rejection are associated with endothelial dysfunction.

  11. EFFECTS OF CHRONIC EXERCISE CONDITIONING ON THERMAL RESPONSES TO LIPOPOLYSACCHARIDE AND TURPENTINE ABSCESS IN FEMALE RATS.

    EPA Science Inventory

    Chronic exercise conditioning has been shown to alter basal thermoregulatory processes as well as the response to inflammatory agents. Two such agents, lipopolysaccharide (LPS) and turpentine (TPT) are inducers of fever in rats. LPS, given intraperitoneally (i.p.), involves a sys...

  12. CHRONIC TOXICITY OF 1,3,5-TRINITROBENZENE IN FISCHER 344 RATS

    EPA Science Inventory

    The chronic toxicity of 1,3,5-trinitrobenzene (TNB) in male and female Fischer 344 (F344) rats was evaluated by feeding a diet containing 0, 5, 60 and 300 ppm of TNB for 2 years. The calculated average TNB intake over 2 years for males and females was 0.22, 2.64, 13.44 and 0.23,...

  13. THERMOREGULATION IN THE RAT DURING CHRONIC, DIETARY EXPOSURE TO CHLORPYRIFOS, AN ORGANOPHOSPHATE INSECTICIDE.

    EPA Science Inventory

    Administration of chlorpyrifos (CHP) at a dose of 25 to 80 mg/kg (p.o.) To rats results in hypothermia followed by a fever lasting for several days. To understand if chronic, low level exposure to CHP affects thermoregulation in a comparable manner to acute administration, male L...

  14. Naked mole rats exhibit metabolic but not ventilatory plasticity following chronic sustained hypoxia.

    PubMed

    Chung, Danielle; Dzal, Yvonne A; Seow, Allison; Milsom, William K; Pamenter, Matthew E

    2016-03-30

    Naked mole rats are among the most hypoxia-tolerant mammals identified and live in chronic hypoxia throughout their lives. The physiological mechanisms underlying this tolerance, however, are poorly understood. Most vertebrates hyperventilate in acute hypoxia and exhibit an enhanced hyperventilation following acclimatization to chronic sustained hypoxia (CSH). Conversely, naked mole rats do not hyperventilate in acute hypoxia and their response to CSH has not been examined. In this study, we explored mechanisms of plasticity in the control of the hypoxic ventilatory response (HVR) and hypoxic metabolic response (HMR) of freely behaving naked mole rats following 8-10 days of chronic sustained normoxia (CSN) or CSH. Specifically, we investigated the role of the major inhibitory neurotransmitter γ-amino butyric acid (GABA) in mediating these responses. Our study yielded three important findings. First, naked mole rats did not exhibit ventilatory plasticity following CSH, which is unique among adult animals studied to date. Second, GABA receptor (GABAR) antagonism altered breathing patterns in CSN and CSH animals and modulated the acute HVR in CSN animals. Third, naked mole rats exhibited GABAR-dependent metabolic plasticity following long-term hypoxia, such that the basal metabolic rate was approximately 25% higher in normoxic CSH animals than CSN animals, and GABAR antagonists modulated this increase.

  15. Chronic ethanol inhibits receptor-stimulated phosphoinositide hydrolysis in rat liver slices

    SciTech Connect

    Gonzales, R.A.; Crews, F.T. )

    1991-03-01

    The effects of chronic ethanol feeding on norepinephrine (NE)- and arginine-vasopressin (AVP)-stimulated phosphoinositide (PI) hydrolysis in rat liver slices was determined. The maximum NE-stimulated PI response was significantly reduced by 40% in liver slices from 8-month-old rats which had been treated for 5 months with a liquid diet containing ethanol compared to pair-fed controls. The maximum AVP-stimulated PI response was decreased by 39% in liver slices from the ethanol-fed rats compared to control. EC50 values for NE- and AVP-stimulated PI hydrolysis in liver slices were not affected by the chronic ethanol treatment. Similar reductions in the maximal NE- and AVP-stimulated PI hydrolysis (28% and 27%, respectively) were found in 22-month-old rats which had been maintained on an ethanol containing diet for 5 months compared to pair-fed controls. The binding of (3H)prazosin and (3H)AVP to liver plasma membranes from 8-month-old ethanol-fed rats was not significantly different from binding to liver membranes from sucrose-fed controls. Our data suggest that chronic ethanol ingestion may lead to a reduction in PI-linked signal transduction in liver.

  16. Very-low-density lipoprotein triglyceride kinetics in acute and chronic carbohydrate-fed rats

    SciTech Connect

    Hirano, T.; Mamo, J.; Poapst, M.; Steiner, G.

    1988-09-01

    Very-low-density lipoprotein (VLDL)-triglyceride (TG) kinetics were examined in rats maintained on either chow and water (control) or chow and a 10% carbohydrate drinking solution (fructose or glucose). The hexose solutions were available for an acute (16 h) or chronic (14 day) period. The acute fructose (AF), acute glucose (AG), and chronic fructose (CF) groups were hypertriglyceridemic (HTG) compared with control. Plasma TG concentration in chronic glucose (CG)-fed rats was similar to control. VLDL-TG was endogenously radiolabeled in donor rats with (2-3H)-glycerol. The fractional catabolic rate (FCR) was then determined by monitoring the clearance of plasma (3H)VLDL-TG in recipient animals. Donors and recipients were treated in an identical manner. AF and CF groups had an FCR significantly lower than rats given glucose for comparable periods. Both fructose groups and the AG group also had a lower FCR than control. In contrast, FCR in the CG group was significantly higher than controls. TG production rate (TGPR) in both AF and CF fed rats did not significantly differ from controls, suggesting that the HTG observed in these animals was solely from a catabolic defect. AG- and CG-treated glucose animals both had TGPR significantly higher than controls. Therefore, overproduction of VLDL-TG contributed to the HTG associated with this carbohydrate.

  17. Impact of chronic stressors on the anxiety profile of pregnant rats.

    PubMed

    de Brito Guzzo, Soliani Flaviane Cristina; Rafael, Cabbia; Matheus Fitipaldi, Batistela; Amarylis Garcia, Almeida; Vinícius Dias, Kümpel; Luiz, Yamauchi Junior; Fernando, Frei; Telma Gonçalves Carneiro Spera de, Andrade

    2015-04-01

    The manifestation of anxiety during pregnancy can be caused by multiple factors and may have emotional and physical consequences for both the mother and the fetus. The prevalence of gestational anxiety has grown in recent years, making the development of studies for its comprehension essential. Thus, the aim of this investigation was to evaluate the effects of predictable and unpredictable chronic stressors on the anxiety profile of rats in three distinct stages of pregnancy (1st, 2nd and 3rd weeks). Wistar dams were divided into three groups: control, social separation and unpredictable chronic stress. Behavioral assessments were conducted in the Elevated Plus-Maze at the end of the 1st, 2nd and 3rd weeks of gestation. The results showed that there was increased anxiety in the proximity of parturition in control dams. Chronic stressors differentially affected the behavior of pregnant rats according to the gestational period where they were applied: social separation decreased anxiety at the end of the 3rd week, while unpredictable chronic stress caused increased anxiety, especially at the end of the 2nd gestational week. These results show that there is a critical time during pregnancy for the onset of anxiety in control rats, depending on the gestational stage. The exposure to different types of chronic stressors may result in distinct behaviors related to this disorder. PMID:25665962

  18. Effects of chronic delta-9-THC treatment on cardiac beta-adrenoceptors in rats

    SciTech Connect

    Evans, E.B.; Seifen, E.; Kennedy, R.H.; Kafiluddi, R.; Paule, M.G.; Scallet, A.C.; Ali, S.F.; Slikker, W. Jr.

    1987-10-01

    This study was designed to determine if chronic treatment with delta-9-tetrahydrocannabinol (THC) alters cardiac beta-adrenoceptors in the rat. Following daily oral administration of 10 or 20 mg/kg THC or an equivalent volume of control solvent for 90 days, rats were sacrificed, and sarcolemmal membranes were prepared from ventricular myocardium. Beta-adrenoceptor density and binding affinity estimated with (-)(/sup 3/H)dihydroalprenolol; a beta-adrenergic antagonist, were not significantly affected by treatment with THC when compared to vehicle controls. These results suggest that the tolerance to cardiovascular effects of THC which develops during chronic exposure in the rat is not associated with alterations in cardiac beta-adrenoceptors as monitored by radiolabeled antagonist binding.

  19. In vitro and in vivo assessment of intraintestinal bacteriotherapy in chronic kidney disease.

    PubMed

    Ranganathan, Natarajan; Patel, Beena G; Ranganathan, Pari; Marczely, Joseph; Dheer, Rahul; Pechenyak, Bohdan; Dunn, Stephen R; Verstraete, Willy; Decroos, Karel; Mehta, Raj; Friedman, Eli A

    2006-01-01

    Chronic kidney disease may progress to end-stage renal disease, which requires dialysis or kidney transplantation. No generally applicable therapies to slow progression of renal disease are available. Bacteriotherapy affords a promising approach to mitigate uremic intoxication by ingestion of live microbes able to catabolize uremic solutes in the gut. The present study evaluates the nonpathogenic soil-borne alkalophilic urease-positive bacterium Sporosarcina pasteurii (Sp) as a potential urea-targeted component for such "enteric dialysis" formulation. Data presented herein suggest that Sp survives through exposure to gastric juice retaining the ability to hydrolyze urea. In vitro, 10 cfu (colony forming units) of Sp removed from 21 +/- 4.7 mg to 228 +/- 6.7 mg urea per hour, depending on pH, urea concentration, and nutrient availability. Beneficial effects of Sp on fermentation parameters in the intestine were demonstrated in vitro in the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) inoculated with fecal microbiota. Enumeration of marker organisms suggested that presence of Sp does not disturb microbial community of the SHIME. Additionally, a pilot study in 5/6th nephrectomized rats fed 10 cfu of live Sp daily throughout the study demonstrated that the tested regimen reduced blood urea-nitrogen levels and significantly prolonged the lifespan of uremic animals.

  20. In vitro and in vivo assessment of intraintestinal bacteriotherapy in chronic kidney disease.

    PubMed

    Ranganathan, Natarajan; Patel, Beena G; Ranganathan, Pari; Marczely, Joseph; Dheer, Rahul; Pechenyak, Bohdan; Dunn, Stephen R; Verstraete, Willy; Decroos, Karel; Mehta, Raj; Friedman, Eli A

    2006-01-01

    Chronic kidney disease may progress to end-stage renal disease, which requires dialysis or kidney transplantation. No generally applicable therapies to slow progression of renal disease are available. Bacteriotherapy affords a promising approach to mitigate uremic intoxication by ingestion of live microbes able to catabolize uremic solutes in the gut. The present study evaluates the nonpathogenic soil-borne alkalophilic urease-positive bacterium Sporosarcina pasteurii (Sp) as a potential urea-targeted component for such "enteric dialysis" formulation. Data presented herein suggest that Sp survives through exposure to gastric juice retaining the ability to hydrolyze urea. In vitro, 10 cfu (colony forming units) of Sp removed from 21 +/- 4.7 mg to 228 +/- 6.7 mg urea per hour, depending on pH, urea concentration, and nutrient availability. Beneficial effects of Sp on fermentation parameters in the intestine were demonstrated in vitro in the Simulator of the Human Intestinal Microbial Ecosystem (SHIME) inoculated with fecal microbiota. Enumeration of marker organisms suggested that presence of Sp does not disturb microbial community of the SHIME. Additionally, a pilot study in 5/6th nephrectomized rats fed 10 cfu of live Sp daily throughout the study demonstrated that the tested regimen reduced blood urea-nitrogen levels and significantly prolonged the lifespan of uremic animals. PMID:16436893

  1. Airway hyperresponsiveness in a rat model of chronic bronchitis: role of C fibers.

    PubMed

    Long, N C; Martin, J G; Pantano, R; Shore, S A

    1997-04-01

    We evaluated the role of C fibers in the development of airway hyperresponsiveness in a rat model of chronic bronchitis. Neonatal rats were treated with capsaicin (50 mg/kg, subcutaneously), a procedure which results in permanent depletion of tachykinins from the lungs and airways as well as degeneration of C fibers. Control rats were treated with the vehicle used to dissolve capsaicin. Three months later, rats from both groups were exposed either to SO2 gas (250 ppm, 5 h/d, 5 d/wk for 4 wk) or to filtered air for the same period of time. One day after the last exposure, rats were anesthetized and instrumented for the measurement of pulmonary resistance (R(L)), dynamic compliance (Cdyn), and airway responsiveness to inhaled aerosolized methacholine. There was a small (30%) but significant increase in R(L) in neonatal capsaicin- but not vehicle-treated rats exposed to SO2. Chronic exposure to SO2 resulted in increased airway responsiveness in both groups of rats, but the effect was more pronounced in the neonatal capsaicin-treated animals in which the doses of methacholine required to double R(L) or decrease Cdyn by 50% decreased 6.3-fold and 4.6-fold, respectively, compared with only 2.2- and 1.3-fold decreases in vehicle-treated rats. Morphometric analysis of histologic sections of airways demonstrated that the average area of smooth muscle in the airway wall, normalized by the length of basement membrane, was significantly greater in SO2 compared with air-exposed capsaicin-treated rats, but not in vehicle-treated control rats (p < 0.012). The maximal tension generated by tracheal rings in response to cholinergic agonists was also significantly increased by SO2 exposure in neonatal capsaicin-treated, but not vehicle-treated rats (p < 0.002). These results support the hypothesis that rather than contributing to the pathophysiologic manifestations of bronchitis, C fibers limit the development of airway obstruction and airway hyperresponsiveness during induction of

  2. [Effect of chronic consumption of alcohol on the hypothalamo-pituitary-testicular axis in the rat].

    PubMed

    Mateos, A; Fermoso, J; Agrasal, C; Martín, I; Paz-Bouza, J; Tresguerres, J A; Esquifino, A I

    1987-03-01

    An experimental model of chronic alcohol abuse is developed, in order to study the hypothalamic-pituitary testicular axis in the rat. For this purpose basal plasma prolactin, gonadotropins, testosterone and estradiol have been measured. Also these hormones were studied after LHRH or hCG stimulation. This experimental model allows us to study the role of alcohol in hypogonadism induction. Chronic alcohol administration resulted in an inconstant decrease in plasma testosterone levels and very diminished response of it to hCG. Along with these modifications, there was an increase in basal plasma estrogen levels, as has been shown in the human. The decrease in plasma LH levels in alcoholic rats together with a normal response to LHRH suggest a toxic role of alcohol at higher levels than the pituitary. The existence of a hyperprolactinemic state under chronic alcohol ingestion is confirmed. The decrease in plasma prolactin levels after LHRH administration suggests that prolactin and gonadotropin secretion are very closely related.

  3. Evaluation of Krebs cycle enzymes in the brain of rats after chronic administration of antidepressants.

    PubMed

    Scaini, Giselli; Santos, Patricia M; Benedet, Joana; Rochi, Natália; Gomes, Lara M; Borges, Lislaine S; Rezin, Gislaine T; Pezente, Daiana P; Quevedo, João; Streck, Emilio L

    2010-05-31

    Several works report brain impairment of metabolism as a mechanism underlying depression. Citrate synthase and succinate dehydrogenase are enzymes localized within cells in the mitochondrial matrix and are important steps of Krebs cycle. In addition, citrate synthase has been used as a quantitative enzyme marker for the presence of intact mitochondria. Thus, we investigated citrate synthase and succinate dehydrogenase activities from rat brain after chronic administration of paroxetine, nortriptiline and venlafaxine. Adult male Wistar rats received daily injections of paroxetine (10mg/kg), nortriptiline (15mg/kg), venlafaxine (10mg/kg) or saline in 1.0mL/kg volume for 15 days. Twelve hours after the last administration, the rats were killed by decapitation, the hippocampus, striatum and prefrontal cortex were immediately removed, and activities of citrate synthase and succinate dehydrogenase were measured. We verified that chronic administration of paroxetine increased citrate synthase activity in the prefrontal cortex, hippocampus, striatum and cerebral cortex of adult rats; cerebellum was not affected. Chronic administration of nortriptiline and venlafaxine did not affect the enzyme activity in these brain areas. Succinate dehydrogenase activity was increased by chronic administration of paroxetine and nortriptiline in the prefrontal cortex, hippocampus, striatum and cerebral cortex of adult rats; cerebellum was not affected either. Chronic administration of venlafaxine increased succinate dehydrogenase activity in prefrontal cortex, but did not affect the enzyme activity in cerebellum, hippocampus, striatum and cerebral cortex. Considering that metabolism impairment is probably involved in the pathophysiology of depressive disorders, an increase in these enzymes by antidepressants may be an important mechanism of action of these drugs.

  4. The effect of chronic calcium treatment on thyroid C cells in ovariectomized rats.

    PubMed

    Filipović, B; Jurjević, B Sosić; Stojanoski, M Manojlović; Nestorović, N; Milosević, V; Sekulić, M

    2005-05-27

    The purpose of this study was to investigate the influence of chronic calcium treatment on the structure and function of thyroid C cells in ovariectomzed adult female rats. Eighteen 3-month-old, female Wistar rats were divided into three groups. The first group was used as the sham-operated control, and the other two were surgically ovariectomized (Ovx). One month after gonadectomy, one group of Ovx rats was injected with 28.55 mg Ca-glucoheptonate (Ca)/kg b.w., while the other two groups were chronically treated with vehicle alone (Ovx and sham control). Two months after surgery, the animals were killed. In the thyroid C cells, calcitonin (CT) was localized with the peroxidase-antiperoxidase method. Stereology was used to evaluate morphometric changes in the volume of C cells, their nuclei and relative volume density. The number of C cells per unit area was calculated. Serum CT content was determined by radioimmunoassay. After chronic Ca treatment C cells were numerous with darker cytoplasm than in C cells of sham-operated control animals, but more degranulated than the corresponding cells of Ovx rats. Their volume was significantly decreased by 14% (p < 0.05), while the number was increased by 47% (p < 0.05) in comparison with corresponding controls. Serum CT concentration was decreased by 27% (n.s.) in comparison to sham-operated control. Calcium treatment of Ovx rats led to a 32% increase of serum CT concentration in relation to untreated Ovx animals. These results suggest that chronic Ca treatment of Ovx female rats positively affected CT release from thyroid C cells, without any significant changes in morphometric parameters.

  5. Contribution of airway closure to chronic postbronchiolitis airway dysfunction in rats.

    PubMed

    Sorkness, Ronald L; Tuffaha, Amjad

    2004-03-01

    Genetically susceptible Brown Norway rats develop a chronic asthmalike syndrome after recovering from viral bronchiolitis at an early age. We hypothesized that airway closure is an important mechanism of airflow obstruction in postbronchiolitis rats. Rats were studied 8-12 wk after inoculation with Sendai virus or sterile vehicle at 3-4 wk of age. Under light pentobarbital anesthesia, rats were instrumented with an orotracheal catheter and an esophageal pressure monitor and placed in a total body plethysmograph. Lung volumes and forced-expiratory maneuvers were measured using the Boyle's law method and software-controlled valving of positive and negative pressures to elicit lung inflations and rapid deflations; pulmonary resistance was measured during spontaneous tidal breathing; and quasi-static pressure-volume curves were obtained with passive inflations and deflations in fully anesthetized, paralyzed rats. Compared with controls, the postbronchiolitis rats had elevated pulmonary resistance and reduced forced-expiratory volume in 0.2 s. Most of the reduced forced-expiratory volume in 0.2 s was associated with reduced forced vital capacity, indicating premature airway closure as a prominent mechanism. The reduced airflow in postbronchiolitis rats was highly dependent on lung volume, being nearly normal at 70% lung capacity, but sevenfold less than normal at 30% lung capacity. Increased respiratory system hysteresis between functional reserve capacity and total lung capacity was evidence for increased airway closure at normal end-expiratory lung volumes in postbronchiolitis rats. We conclude that airway instability and closure is a prominent mechanism of the chronic airway dysfunction in rats that have recovered from viral bronchiolitis at an early age. PMID:14594863

  6. Neonatal capsaicin treatment in rats induces chronic hyperthermia resulting in infectious disease

    PubMed Central

    JEONG, KEUN-YEONG; KIM, HWAN MOOK

    2015-01-01

    Treatment of neonatal animals with capsaicin has previously been associated with long-lasting hyperthermia and severe cutaneous lesions. The present study analyzed the effects of capsaicin-induced hyperthermia on the occurrence of infectious disease and pruritic dermatitis in a rat model. Pregnant Sprague-Dawley (SD) rats were obtained 1 week prior to parturition. Pups from each litter were randomly assigned to the following experimental groups: Capsaicin-treated (cap-treated; n=10) or vehicle-treated (n=5). Capsaicin (50 mg/kg) or vehicle were systemically administered to the SD rat pups (age, 48 h), after which body temperature was measured using a biotelemetry system, and the effects of hyperthermia on the ability of the rat pups to resist bacterial infection were analyzed. Furthermore, pruritus-induced scratching behavior and dermatitis were assessed, and changes in interleukin (IL)-4- and IL-13-induced immunoglobulin E expression were measured. Treatment of neonatal rats with capsaicin resulted in chronic hyperthermia, which had negative effects on the host immune defense response. The expression levels of T-helper type 2 cell-associated cytokines were significantly increased (P<0.01) in the cap-treated rats following bacterial infection with Staphylococcus aureus or Streptococcus agalactiae. Furthermore, cap-treated rats exhibited pruritus-induced scratching behavior and dermatitis. The results of the present study suggested that treatment of neonatal rats with capsaicin induces chronic hyperthermia and decreases the effectiveness of the host defense system. Therefore, a cap-treated neonatal rat model may be considered useful when investigating the association between hyperthermia and infectious disease. PMID:26668650

  7. Expression of Melanocortin-4 Receptor mRNA in Male Rat Hypothalamus During Chronic Stress

    PubMed Central

    Karami Kheirabad, Maryam; Namavar Jahromi, Bahia; Tamadon, Amin; Ramezani, Amin; Ahmadloo, Somayeh; Sabet Sarvestan, Fatemeh; Koohi-Hosseinabadi, Omid

    2015-01-01

    The effects of chronic stress and glucocorticoids receptor antagonist (RU486) on expression of melanocortin 4 receptor (MC4R) mRNA in arcuate nucleus (ARC) of male rats were evaluated. In this study, adult male Sprague Dawley rats were placed into four groups (n=6/group); stress, RU486, stress/RU486, and control groups. In stress group, the rats were restrained, 1 h/day, for 12 days. In RU486 group, the rats were injected RU486 for 12 days. In stress/RU486 group, the rats were injected RU486 1 h before the stress process for 12 days. Relative expression of MC4R mRNA was determined using real-time PCR. Relative expression of MC4R mRNA in the stress group was higher than that of the control rats (P<0.05). Relative expressions of MC4R mRNA were not different between the stress, RU486 and stress/RU486 groups (P>0.05). Chronic restraint stress causes increase in mRNA expression of MC4R in ARC and blockade of glucocorticoid receptors has no effect on this up-regulation. PMID:26629487

  8. Metabolic and behavioral effects of chronic olanzapine treatment and cafeteria diet in rats.

    PubMed

    Muller, Alexandre P; Tort, Ana H; Gnoatto, Jussânia; Moreira, Julia D; Vinadé, Elsa R; Perry, Marcos L; Souza, Diogo O; Lara, Diogo R; Portela, Luis V

    2010-10-01

    Olanzapine and highly palatable diets can alter metabolism and brain function. We investigated the interaction of chronic treatment (4 months) with olanzapine and a cafeteria diet on metabolic parameters, memory tasks (spatial and aversive), the elevated plus maze and locomotor activity induced by d-amphetamine. Male Wistar rats were separated into the following groups: standard diet vehicle, standard diet and olanzapine, cafeteria diet vehicle and cafeteria diet and olanzapine. Olanzapine was administered in the drinking water (approximately 1.5 mg/kg/day), and after 3 days of treatment, the rats exhibited an expected anxiolytic effect and reduced amphetamine-induced hyperlocomotion. After 4 months of treatment, cafeteria diet vehicle and cafeteria diet olanzapine rats exhibited an increased body weight and heavier fat pads compared with the standard diet groups. Olanzapine increased only the epididymal and mesenteric fat pads. The cafeteria diet and olanzapine group showed greater glucose intolerance compared with all other groups. The cafeteria diet altered the effects of chronic olanzapine on the performance in the water maze and inhibitory avoidance tasks. Chronic olanzapine treatment failed to affect amphetamine-induced locomotion and to produce anxiolytic effects in the elevated plus maze task, regardless of the diet. Our results suggest that chronic olanzapine caused an increase in fat pads, which is putatively involved in the etiology of many metabolic diseases. Rats on the cafeteria diet were overweight and exhibited glucose intolerance. We did not observe these effects with olanzapine treatment with the standard diet. Moreover, the chronic treatment regimen caused tolerance to the antipsychotic and anxiolytic effects of olanzapine and seemed to potentiate some of the metabolic effects of the cafeteria diet. The cafeteria diet also modified the effects of chronic treatment with olanzapine on cognitive tasks, which may represent an undesirable effect of

  9. Effects of milnacipran on cognitive flexibility following chronic stress in rats.

    PubMed

    Naegeli, Kale J; O'Connor, Joann A; Banerjee, Pradeep; Morilak, David A

    2013-03-01

    Cognitive dysfunction is a component of affective disorders, including depression. Chronic stress is a risk factor for depression, and we have shown that exposing rats to chronic unpredictable stress (CUS) induces a deficit of cognitive flexibility, the ability to modify behavior based on feedback from a changing environment. Deficits of cognitive flexibility, measured by extra-dimensional set-shifting on the Attentional Set-shifting Test (AST), are consistent with dysregulation of prefrontal cortical function, also characteristic of depression. We have shown that increasing norepinephrine in the medial prefrontal cortex facilitated set-shifting, and chronic treatment with the selective norepinephrine reuptake blocker, desipramine, restored cognitive flexibility in rats that had been compromised by CUS. Serotonin reuptake blockade also prevented CUS-induced deficits in cognitive flexibility, suggesting a role for both monoamines in this process. Milnacipran is a serotonin-norepinephrine reuptake inhibitor (SNRI) with moderate preference for blocking norepinephrine reuptake. In this study, we tested the effects of chronic milnacipran treatment on cognitive set-shifting after CUS. Male Sprague-Dawley rats were treated chronically by minipump with milnacipran (30 mg/kg/day), the positive control drug, desipramine (5mg/kg/day), or vehicle, and exposed to CUS or unstressed control conditions. For CUS, a different acute stressor was presented daily for 14 days. On Day 17, rats were tested on the AST. Consistent with previous results, CUS impaired cognitive set-shifting. Further, chronic treatment with either milnacipran or desipramine preserved cognitive flexibility after CUS, suggesting that milnacipran may have efficacy in the management of cognitive dysfunction as a component of stress-related illnesses, including fibromyalgia and depression. PMID:23422875

  10. Impact of aluminum sub-chronic toxicity on body weight and recognition memory of wistar rat.

    PubMed

    Azzaoui, F Z; Ahami, A O T; Khadmaoui, A

    2008-07-15

    The aims of this study was to investigate the impact of aluminum nitrate administered in drinking water during 90 days (sub-chronic toxicity), on body weight gain, motor activity, brain aluminum accumulation and especially in recognition memory of wistar rats. Two groups of young female wistar rats were used. Treated rats received (80 mg L(-1)) of aluminum nitrate diluted in drinking water, while control rats received a drinking water only, for 3 months. An evolution of body weight, a motor activity, object recognition memory (NOR) and brain aluminum concentration has been evaluated. The body weight was taken weekly, whereas the memory abilities and the motor activity are measured once every fortnight alternatively, by submitting rats to the open field test and to the novel object recognizing memory test. The results have showed a significant decrease in rats' body weight (p < 0.05). Though, no significance was registered for motor activity. Nevertheless, a high significance is showed for recognition memory compared to control rats (p < 0.01), especially at the end of testing period, even the difference between control and aluminium treated rats in brain aluminum levels was not significant.

  11. Chronic Loss of Melanin-Concentrating Hormone Affects Motivational Aspects of Feeding in the Rat

    PubMed Central

    Mul, Joram D.; la Fleur, Susanne E.; Toonen, Pim W.; Afrasiab-Middelman, Anthonieke; Binnekade, Rob; Schetters, Dustin; Verheij, Michel M. M.; Sears, Robert M.; Homberg, Judith R.; Schoffelmeer, Anton N. M.; Adan, Roger A. H.; DiLeone, Ralph J.; De Vries, Taco J.; Cuppen, Edwin

    2011-01-01

    Current epidemic obesity levels apply great medical and financial pressure to the strenuous economy of obesity-prone cultures, and neuropeptides involved in body weight regulation are regarded as attractive targets for a possible treatment of obesity in humans. The lateral hypothalamus and the nucleus accumbens shell (AcbSh) form a hypothalamic-limbic neuropeptide feeding circuit mediated by Melanin-Concentrating Hormone (MCH). MCH promotes feeding behavior via MCH receptor-1 (MCH1R) in the AcbSh, although this relationship has not been fully characterized. Given the AcbSh mediates reinforcing properties of food, we hypothesized that MCH modulates motivational aspects of feeding. Here we show that chronic loss of the rat MCH-precursor Pmch decreased food intake predominantly via a reduction in meal size during rat development and reduced high-fat food-reinforced operant responding in adult rats. Moreover, acute AcbSh administration of Neuropeptide-GE and Neuropeptide-EI (NEI), both additional neuropeptides derived from Pmch, or chronic intracerebroventricular infusion of NEI, did not affect feeding behavior in adult pmch+/+ or pmch−/− rats. However, acute administration of MCH to the AcbSh of adult pmch−/− rats elevated feeding behavior towards wild type levels. Finally, adult pmch−/− rats showed increased ex vivo electrically evoked dopamine release and increased limbic dopamine transporter levels, indicating that chronic loss of Pmch in the rat affects the limbic dopamine system. Our findings support the MCH-MCH1R system as an amplifier of consummatory behavior, confirming this system as a possible target for the treatment of obesity. We propose that MCH-mediated signaling in the AcbSh positively mediates motivational aspects of feeding behavior. Thereby it provides a crucial signal by which hypothalamic neural circuits control energy balance and guide limbic brain areas to enhance motivational or incentive-related aspects of food consumption. PMID

  12. Effect of chronic stress on spatial memory in rats is attenuated by lithium treatment.

    PubMed

    Vasconcellos, A P S; Tabajara, A S; Ferrari, C; Rocha, E; Dalmaz, C

    2003-07-01

    Stress is known to alter cognitive functions, such as memory, and it has been linked to the pathophysiology of mood and anxiety disorders. Chronic lithium treatment is used in some psychiatric disorders and has been suggested to act upon mechanisms which can enhance neuronal viability. The purpose of this work is to investigate a possible effect of lithium treatment in a chronic stress model. Adult male Wistar rats were divided in two groups, control and chronically stressed, treated either with normal chow or with chow containing LiCl for 40 days. Stress treatment was a chronic variable stress model, consisting of different stressors which were applied in a random fashion, once a day, every day. Memory was assessed by using the water maze task. The results demonstrated a marked decrease in reference memory in the water maze task in chronically stressed rats. This effect was attenuated by lithium treatment in all the parameters considered. No effect was observed in the working memory. These results indicate that lithium treatment may counteract some effects of chronic stress situations, particularly concerning spatial memory.

  13. Exploring the potential of telmisartan in chronic constriction injury-induced neuropathic pain in rats.

    PubMed

    Jaggi, Amteshwar Singh; Singh, Nirmal

    2011-09-30

    The present study was designed to investigate the potential of telmisartan, an angiotensin AT(1) receptor, in chronic constriction injury-induced neuropathic pain in rats. Four loose ligatures were placed around the sciatic nerve to induce chronic constriction injury and neuropathic pain. Acetone drop, pin-prick, hot plate and paint brush tests were performed to assess cold allodynia; mechanical and heat hyperalgesia; and dynamic mechanical allodynia, respectively along with assessment of spontaneous pain and postural index in terms of foot deformity. The levels of TNF-α were measured in the sciatic nerve as an index of inflammation. Chronic constriction injury was associated with development of cold allodynia; mechanical and heat hyperalgesia; dynamic mechanical allodynia; and spontaneous pain and foot deformity along with rise in the levels of TNF-α. Telmisartan (1, 2, 5 mg/kg, p.o.) was administered for 14 days in chronic constriction injury subjected rats. Administration of telmisartan (2, 5 mg/kg) significantly attenuated chronic constriction injury-induced pain related behavior, foot deformity and rise in TNF-α level. It may be concluded that telmisartan has a potential in attenuating neuropathic pain behavior in chronic constriction injury model which may possibly be attributed to its anti-inflammatory properties. PMID:21741378

  14. Expression of Serotonin Receptors in the Colonic Tissue of Chronic Diarrhea Rats

    PubMed Central

    Zhu, Tong; Qiu, Juanjuan; Wan, Jiajia; Wang, Fengyun; Tang, Xudong; Guo, Huishu

    2016-01-01

    Background/Aims: This study aimed to investigate the difference among the expression of serotonin receptors (5-HT3, 5-HT4, and 5-HT7 receptors) in colonic tissue of chronic diarrhea rats. Materials and Methods: A rat model of chronic diarrhea was established by lactose diet. The expression of 5-HT3, 5-HT4, and 5-HT7 receptors in the colonic tissue was detected using immunohistochemistry, real-time PCR and Western blotting techniques. Results: There is no significant difference on the protein expression of 5-HT3 receptor between the normal group and the chronic diarrhea model group. The mRNA expression of 5-HT3 receptor in the chronic diarrhea model group was significantly lower than that in the normal group (n = 10; P < 0.01). The protein and mRNA expression of 5-HT4 receptor in the chronic diarrhea model group were significantly higher than those in the normal group (n = 10; P < 0.05, P < 0.01). On the contrary, the protein and mRNA expressions of 5-HT7 receptor in the chronic diarrhea model group were significantly decreased compared with the normal group (n = 10; P < 0.01, P < 0.01). Conclusions: The results suggested the receptors of 5-HT4 and 5-HT7 may be involved in inducing diarrhea by lactose diet. PMID:27184643

  15. Insulin resistance in SD rats chronically treated with ethanol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We have previously demonstrated that hepatic insulin signaling is disrupted in Sprague-Dawley (SD) rats fed EtOH-containing diets by total enteral nutrition (TEN). To determine if whole body insulin resistance could be demonstrated in the TEN model, we conducted euglycemic-hyperinsulinemic clamp st...

  16. A cognitive deficit induced in rats by chronic intermittent cold stress is reversed by chronic antidepressant treatment

    PubMed Central

    Danet, M.; Lapiz-Bluhm, S.; Morilak, David A.

    2010-01-01

    We have previously reported that 14-days of chronic intermittent cold (CIC) stress induced a cognitive deficit in reversal learning on the rat attentional set-shifting test. This effect may be related to dysregulation of 5-HT function in orbitofrontal cortex, as a model of cognitive dysfunction in depression. To test the ability of chronic antidepressant drug treatment to reverse the cognitive deficit induced by CIC, it was first necessary to assess the temporal characteristics of the CIC-induced cognitive deficit. Thus, in the first study, we assessed the duration of the cognitive deficit following 2-weeks CIC stress. Replicating previous experiments, CIC induced a reversal learning deficit tested 3 days after the last cold exposure. However, cognitive performance of CIC-stressed rats was no different from unstressed controls when tested 7, 14 or 21 days after termination of the stress treatment. We next compared behavior 3 days after 2-weeks CIC to that seen 3 days after 5-weeks CIC, and found similar deficits in reversal learning. Thus, in the final study, antidepressant drug treatment was initiated after 2-weeks of CIC stress, and was maintained for 3 weeks, concurrent with the continuation of CIC stress. Both chronic and acute treatment with the selective serotonin reuptake inhibitor, citalopram, but not the norepinephrine reuptake blocker, desipramine, reversed the cognitive deficit induced by CIC stress. Thus, this stress-induced cognitive deficit may be a useful model for cognitive deficits related to prefrontal cortical hypoactivity in depression, and for investigating neurobiological mechanisms underlying the beneficial effects of chronic antidepressant drug treatment. PMID:20149267

  17. Suppression of serum gonadal steroids in rats by chronic treatment with dopamine and serotonin reuptake inhibitors.

    PubMed

    Rehavi, M; Attali, G; Gil-Ad, I; Weizman, A

    2000-05-01

    The impact of chronic administration (3 weeks) of dopamine and serotonin reuptake inhibitors on serum gonadal steroid hormones and prolactin was studied in intact male and female rats. Both the dopamine and the serotonin reuptake inhibitors lowered serum estradiol and progesterone levels in the female rats. The dopamine transporter blockers suppressed testosterone serum levels in the male rats, whereas serotonin reuptake inhibitors induced only a non-significant reduction (30%) of this hormone. In contrast to the decrease in gonadal steroids, none of the serotonin or the dopamine reuptake blockers altered prolactin serum levels in either the male or female rats. It seems that the effect of these agents on ovarian and testicular hormones is related to the impact of the monoamine reuptake inhibitors on the hypothalamic-pituitary-gonadal axis.

  18. Chronic Oral Pelargonidin Alleviates Learning and Memory Disturbances in Streptozotocin Diabetic Rats

    PubMed Central

    Mirshekar, Mohammadali; Roghani, Mehrdad; Khalili, Mohsen; Baluchnejadmojarad, Tourandokht

    2011-01-01

    Diabetes mellitus is accompanied with disturbances in learning, memory, and cognitive skills in the humans and experimental animals. Due to the anti-diabetic and antioxidant activity of pelargonidin (PG), this research study was conducted to evaluate the efficacy of chronic oral PG on alleviating learning and memory disturbance in streptozotocin-diabetic rats. Male Wistar rats were divided into control, diabetic, PG-treated control and PG (single-and/or multiple-dose)-treated diabetic groups. PG was administered p.o. once at a dose of 10 mg/kg and/or multiple doses on alternate days for 8 weeks. For induction of diabetes, streptozotocin (STZ) was injected IP in a single dose of 60 mg/kg. For the evaluation of learning and memory, initial latency (IL) and step-through latency (STL) were determined at the end of study using a passive avoidance test. Meanwhile, spatial memory was assessed in a Y-maze task. It was found that the alternation score of the diabetic rats was lower than the control (p < 0.05) and that single dose PG-treated diabetic rats (p < 0.05) showed a higher alternation score in comparison with the diabetic group. Regarding initial latency, there was no significant difference among the groups. In addition, diabetic and single-dose PG-treated diabetic rats developed a significant impairment in retention and recall in the passive avoidance test (p < 0.01), as was evident by a lower STL. Furthermore, the retention and recall of multiple-dose PG-treated diabetic rats was significantly higher in comparison with diabetic rats (p < 0.05). Therefore, it can be concluded that single-dose oral PG may attenuate spatial memory in the Y maze paradigm and multiple-dose chronic PG could improve retention and recall capability in the passive avoidance test in STZ-diabetic rats. PMID:24250390

  19. Chronic biliary obstruction induces pulmonary intravascular phagocytosis and endotoxin sensitivity in rats.

    PubMed Central

    Chang, S W; Ohara, N

    1994-01-01

    Endotoxin sensitivity varies among animal species and appears to correlate with the presence of pulmonary intravascular macrophage (PIM). In rats, which lack PIM, we investigated the hypothesis that chronic cholestatic liver injury leads to induction of PIM and endotoxin sensitivity. Rats were randomized to either common bile duct ligation (BDL) or sham-surgery and studied at 1 wk (acute cholestasis), 2 wk (cholestasis, early cirrhosis), and 4 wk (cholestasis, established cirrhosis) after surgery. Intravascularly injected fluorescent latex microspheres (1 micron diameter) were taken up by large phagocytic cells in lung parenchyma of BDL rats (at 2 and 4 wk), while no uptake was observed in lungs from control rats. Electronmicroscopy revealed accumulation of large, mononuclear, macrophage-like cells containing ingested latex particles within the pulmonary capillaries. Pulmonary intravascular phagocytosis, as reflected in lung uptake of 99mTc microaggregated albumin (Microlite, mean particle diameter = 1 micron), averaged 0.7 +/- 0.1% (mean +/- SEM) of total injected dose in 13 control rats and progressively increased with time after BDL (1 wk, 1.7 +/- 0.2%; 2 wk, 10.0 +/- 3.0%; 4 wk 35.1 +/- 5.9%). Rats with biliary cirrhosis were markedly sensitive to the lethal effects of low dose endotoxin and demonstrated marked lung edema at the time of death. Furthermore, the lung uptake of intravascular 125I-lipopolysaccharide was increased five-fold in cirrhotic rats. We conclude that chronic biliary obstruction leads to the induction of pulmonary intravascular phagocytes and enhances endotoxin sensitivity in rats. Pulmonary intravascular phagocytosis in patients with advanced cirrhosis may account for their increased susceptibility to sepsis-induced adult respiratory distress syndrome. Images PMID:7962547

  20. Effect of chronic exposure to aspartame on oxidative stress in the brain of albino rats.

    PubMed

    Iyyaswamy, Ashok; Rathinasamy, Sheeladevi

    2012-09-01

    This study was aimed at investigating the chronic effect of the artificial sweetener aspartame on oxidative stress in brain regions of Wistar strain albino rats. Many controversial reports are available on the use of aspartame as it releases methanol as one of its metabolite during metabolism. The present study proposed to investigate whether chronic aspartame (75 mg/kg) administration could release methanol and induce oxidative stress in the rat brain. To mimic the human methanol metabolism, methotrexate (MTX)-treated rats were included to study the aspartame effects. Wistar strain male albino rats were administered with aspartame orally and studied along with controls and MTX-treated controls. The blood methanol level was estimated, the animal was sacrificed and the free radical changes were observed in brain discrete regions by assessing the scavenging enzymes, reduced glutathione, lipid peroxidation (LPO) and protein thiol levels. It was observed that there was a significant increase in LPO levels, superoxide dismutase (SOD) activity, GPx levels and CAT activity with a significant decrease in GSH and protein thiol. Moreover, the increases in some of these enzymes were region specific. Chronic exposure of aspartame resulted in detectable methanol in blood. Methanol per se and its metabolites may be responsible for the generation of oxidative stress in brain regions.

  1. Effects of chronic crocin treatment on desoxycorticosterone acetate (doca)-salt hypertensive rats

    PubMed Central

    Imenshahidi, Mohsen; Razavi, Bibi Marjan; Faal, Ayyoob; Gholampoor, Ali; Mousavi, Seyed Mehran; Hosseinzadeh, Hossein

    2014-01-01

    Objective(s): In this study, the effects of chronic administration of crocin, an active constituent of saffron, on blood pressures of normotensive and desoxycorticosterone acetate (DOCA) - salt induced hypertensive rats, were investigated. Materials and Methods: Five week administration of three doses of crocin (50, 100 and 200 mg/kg/day) and spironolactone (50 mg/kg/day) in different groups of normotensive and hypertensive rats (at the end of 4 weeks treatment by DOCA-salt) was carried out and their effects on mean systolic blood pressure (MSBP) and heart rate (HR) were evaluated using tail cuff method. The duration of effect of crocin on SBP, was also evaluated. Results: Our results indicated that chronic administration of crocin could reduce the MSBP in DOCA salt treated rats in a dose dependent manner. Crocin did not decrease the MSBP in normotensive rats. The data also showed that antihypertensive effects of crocin did not persist. Conclusion: It is concluded that crocin possesses antihypertensive and normalizing effect on BP in chronic administration. PMID:24592301

  2. Interaction between vitamin E and glutathione in rat brain: Effect of chronic ethanol administration.

    PubMed

    Marcus, S R; Chandrakala, M V; Nadiger, H A

    1998-12-01

    The protection against ethanol-induced lipid peroxidation is rendered by antioxidants such as vitamin E and glutathione (GSH) interacting with each other and also functioning independently. A study of the levels of GSH and activities of glutathione peroxidase (GP), glutathione reductase (GR) and glutathione transferase (GST) in the cerebral cortex (CC), cerebellum (CB) and brain stem (BS) of vitamin E-supplemented and -deficient rats subjected to ethanol administration for 30 days was carried out. Chronic ethanol administration to vitamin E-supplemented rats elevated GP, GR and GST activities in the three regions and GSH levels in the CB. Chronic ethanol administration to vitamin E-deficient rats elevated GR activity in the three regions and GP activity in the CC and CB, decreased GST activity in the CC and CB, but did not alter GSH levels compared with normal rats subjected to chronic ethanol administration. The results indicate that vitamin E helps to maintain GSH levels to combat increased peroxidation while its absence has a deleterious effect.

  3. Role of intestinal microflora in chronic inflammation and ulceration of the rat colon.

    PubMed Central

    Videla, S; Vilaseca, J; Guarner, F; Salas, A; Treserra, F; Crespo, E; Antolín, M; Malagelada, J R

    1994-01-01

    Bacteria and their products stimulate inflammatory responses. The effects of different antimicrobial regimens (amoxicillin/clavulanic acid, tobramycin, imipenem, vancomycin, metronidazole) were investigated on the course of experimental colitis induced by trinitrobenzenesulphonic acid (TNB) in the rat. On day 7 and 21 after the induction of colitis, matched groups of control and antibiotic treated rats were subjected to colonic dialysis to measure eicosanoid release, and killed for morphological assessment of the colonic lesions (macro and microscopic scores). Stool samples were cultured. Selective antibiotic treatment against Gram positive, Gram negative or anaerobic bacteria had no effect on colonic lesion scores. By contrast, certain broad spectrum antibiotics (amoxicillin/clavulanic acid or the association of imipenem plus vancomycin) significantly reduced macro and microscopic scores. Rats receiving these antibiotics did not develop chronic colitis as shown by the virtual absence of colonic strictures, adhesions, fibrosis, and granulomas. On day 21 after TNB, the intracolonic release of prostaglandin E2, thromboxane B2, and leukotriene B4 was significantly higher in control than in antibiotic treated rats. Control stool cultures showed abundant colony forming units of both aerobic and anaerobic bacteria. Amoxicillin/clavulanic acid and imipenem plus vancomycin induced appreciable reductions in luminal bacteria. In conclusion, certain broad spectrum antibiotics prevent chronic colitis. The normal colonic flora seems to play an important pathogenetic part in the progression of inflammatory colonic lesions to chronicity. PMID:7926912

  4. Chronic postnatal ornithine administration to rats provokes learning deficit in the open field task.

    PubMed

    Viegas, Carolina Maso; Busanello, Estela Natacha Brandt; Tonin, Anelise Miotti; Grings, Mateus; Moura, Alana Pimentel; Ritter, Luciana; Zanatta, Angela; Knebel, Lisiane Aurélio; Lobato, Vannessa Araujo; Pettenuzzo, Letícia Ferreira; Vargas, Carmen Regla; Leipnitz, Guilhian; Wajner, Moacir

    2012-12-01

    Hyperornithinemia is the biochemical hallmark of hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome, an inherited metabolic disease clinically characterized by mental retardation whose pathogenesis is still poorly known. In the present work, we produced a chemical animal model of hyperornithinemia induced by a subcutaneous injection of saline-buffered Orn (2-5 μmol/g body weight) to rats. High brain Orn concentrations were achieved, indicating that Orn is permeable to the blood brain barrier. We then investigated the effect of early chronic postnatal administration of Orn on physical development and on the performance of adult rats in the open field, the Morris water maze and in the step down inhibitory avoidance tasks. Chronic Orn treatment had no effect on the appearance of coat, eye opening or upper incisor eruption, nor on the free-fall righting reflex and on the adult rat performance in the Morris water maze and in the inhibitory avoidance tasks, suggesting that physical development, aversive and spatial localization were not changed by Orn. However, Orn-treated rats did not habituate to the open field apparatus, implying a deficit of learning/memory. Motor activity was the same for Orn- and saline- injected animals. We also verified that Orn subcutaneous injections provoked lipid peroxidation in the brain, as determined by a significant increase of thiobarbituric acid-reactive substances levels. Our results indicate that chronic early postnatal hyperornithinemia may impair the central nervous system, causing minor disabilities which result in specific learning deficiencies. PMID:22699997

  5. Immunohistochemical changes and atrophy after chronic ethanol intoxication in rat salivary glands.

    PubMed

    Fernandes, Luanna Melo Pereira; Teixeira, Francisco Bruno; Alves-Junior, Sergio Melo; Pinheiro, João de Jesus Viana; Maia, Cristiane Socorro Ferraz; Lima, Rafael Rodrigues

    2015-09-01

    Alcoholism in humans is a chronic and progressive disease, characterized by loss of ethanol consumption control. Previous studies have reported that prolonged exposure to ethanol was responsible for alterations in glandular tissues of human and rodents. However, the interrelationship between ethanol and the glandular system is still the subject of numerous investigations, including the possible resistance of the submandibular gland (SG). In the present study, we investigated whether chronic ethanol exposure during adolescence may affect the parotid gland (PG) and SG in female rats. Female rats (n=16) were treated with distilled water or ethanol (dose of 6.5 g/kg/day, 22.5% w/v) through gavage for 55 days. Glands were collected, weighed and submitted to histological processing. Morphometric analysis was assessed by parenchymal and stromal area measurements. Smooth muscle actin (α-SMA), cytokeratin-19 (CK19) and apoptotic caspase-3 (CAS) were measured using ImageJ® software. Chronic ethanol administration did not alter the body weight of rats after treatment, although it increased glandular weight (p<0.001), reduced the parenchyma area (p<0.001) and decreased CK19 and α-SMA immunostainning in the PG. Besides, ethanol induced CK19 and CAS overexpression, and the occurrence of duct-like structures in SG. These results suggest that ethanol induces histological and morphometric changes in salivary glands of female rats intoxicated with ethanol during adolescence. Furthermore, the mechanism underlying these alterations needs to be investigated but may be not related to the inflammatory process.

  6. The Effect of Chronic Administration of Safranal on Systolic Blood Pressure in Rats

    PubMed Central

    Imenshahidi, Mohsen; Razavi, Bibi Marjan; Faal, Ayyoob; Gholampoor, Ali; Mousavi, Seyed Mehran; Hosseinzadeh, Hossein

    2015-01-01

    Safranal, the main component of Crocus sativus essential oil, exhibits different pharmacological activities. In this study, the effects of safranal, on blood pressure of normotensive and desoxycorticosterone acetate (DOCA) - salt induced hypertensive rats in chronic administration were investigated. Three doses of safranal (1, 2 and 4 mg/Kg/day) and spironolactone (50 mg/Kg/day) were administrated to the different groups of normotensive and hypertensive rats (at the end of 4 weeks treatment by DOCA-salt) for Five weeks. Then the effects of safranal on mean systolic blood pressure (MSBP) and heart rate (HR) were evaluated using tail cuff method. The duration of effect of safranal on SBP, was also evaluated. Our results indicated that chronic administration of safranal could reduce the MSBP in DOCA salt treated rats in a dose dependent manner. Safranal did not decrease the MSBP in normotensive rats. The data also showed that antihypertensive effects of safranal did not persist. In summary, our results showed that safranal exhibits antihypertensive and normalizing effect on BP in chronic administration. PMID:25901167

  7. Chronic Psychosocial Stress Impairs Bone Homeostasis: A Study in the Social Isolation Reared Rat.

    PubMed

    Schiavone, Stefania; Morgese, Maria G; Mhillaj, Emanuela; Bove, Maria; De Giorgi, Angelo; Cantatore, Francesco P; Camerino, Claudia; Tucci, Paolo; Maffulli, Nicola; Cuomo, Vincenzo; Trabace, Luigia

    2016-01-01

    Chronic psychosocial stress is a key player in the onset and aggravation of mental diseases, including psychosis. Although a strong association between this psychiatric condition and other medical co-morbidities has been recently demonstrated, few data on the link between psychosis and bone homeostasis are actually available. The aim of this study was to investigate whether chronic psychosocial stress induced by 4 or 7 weeks of social isolation in drug-naïve male Wistar rats could alter bone homeostasis in terms of bone thickness, mineral density and content, as well as markers of bone formation and resorption (sclerostin, cathepsin K, and CTX-I). We found that bone mineral density was increased in rats exposed to 7 weeks of social isolation, while no differences were detected in bone mineral content and area. Moreover, 7 weeks of social isolation lead to increase of femur thickness with respect to controls, suggesting the development of a hyperostosis condition. Isolated rats showed no changes in sclerostin levels, a marker of bone formation, compared to grouped animals. Conversely, bone resorption markers were significantly altered after 7 weeks of social isolation in terms of decrease in cathepsin K and increase of CTX-I. No alterations were found after 4 weeks of isolation rearing. Our observations suggest that chronic psychosocial stress might affect bone homeostasis, more likely independently from drug treatment. Thus, the social isolation model might help to identify possible new therapeutic targets to treat the burden of chronic psychosocial stress and to attempt alternative therapy choices.

  8. Chronic psychosocial stress makes rats more 'pessimistic' in the ambiguous-cue interpretation paradigm.

    PubMed

    Papciak, Justyna; Popik, Piotr; Fuchs, Eberhard; Rygula, Rafal

    2013-11-01

    Human decisions are often biased by emotions. Stressed and depressed individuals tend to make negative, pessimistic judgements while those in positive affective states are often more optimistic. Chronic psychosocial stress has previously been shown to induce a spectrum of behavioural and physiological changes in rats that are considered the correlates of depressive symptoms in humans. In this study, we investigate whether chronic social defeat makes animals more 'pessimistic'. To measure the changes in cognitive judgement bias, we applied the ambiguous-cue interpretation paradigm. In the operant boxes, the rats were trained to press one lever in response to one tone to receive a reward and to press another lever in response to a different tone to avoid punishment. Cognitive bias was tested by measuring the pattern of animals' responses to a tone of intermediate frequency (ambiguous-cue). To induce chronic psychosocial stress, we subjected the animals to daily social defeat in the resident-intruder paradigm for 3 weeks. We report that chronic psychosocial stress makes rats more pessimistic.

  9. Quality of life in predialytic uremic patients.

    PubMed

    Klang, B; Björvell, H; Clyne, N

    1996-02-01

    This study describes and analyses how 38 predialytic uremic patients perceived their sense of well-being, functional ability, level of anxiety and sense of coherence. The patients in this study reported decreased sense of well-being, considerable functional disabilities, and a high level of anxiety when compared to a healthy reference group. These observations were independent of laboratory data with the exception of hemoglobin concentration which showed a significant negative correlation to the SIP scale work. There was a significant negative correlation between the scores of sense of coherence and anxiety. Patients with a weak sense of coherence and a high level of anxiety perceived their well-being as being worse than those with higher scores in the sense of coherence test and lower scores in the level of anxiety test. Sense of well-being in turn influenced functional ability in daily life. Social and marital status also affected the results. These results indicate that the investigated group of predialytic patients have a decrease in quality of life. The results obtained provide a useful instrument showing in which areas care should be concentrated and in what way patients' own resources need to be strengthened while preparing for dialysis treatment.

  10. Effect of chronic stress on synaptic currents in rat hippocampal dentate gyrus neurons.

    PubMed

    Karst, Henk; Joëls, Marian

    2003-01-01

    We investigated the effect of chronic stress on synaptic responses of rat dentate granule cells to perforant path stimulation. Rats were subjected for 3 wk to unpredictable stressors twice daily or to control handling. One day after the last stressor, hippocampal slices were prepared and synaptic responses were determined with whole-cell recording. At that time, adrenal weight was found to be increased and thymus weight as well as gain in body weight were decreased in the stressed versus control animals, indicative of corticosterone hypersecretion during the stress period. In slices from rats with basal corticosteroid levels (at the circadian trough, under rest), no effect of prior stress exposure was observed on synaptic responses. However, synaptic responses of dentate granule cells from chronically stressed and control rats were differently affected by in vitro activation of glucocorticoid receptors, i.e., 1-4 h after administration of 100 nM corticosterone for 20 min. Thus the maximal response to synaptic activation of dentate cells at holding potential of -70 mV [when N-methyl-D-aspartate (NMDA) receptors are blocked by magnesium] was significantly enhanced after corticosterone administration in chronically stressed but not in control animals. In accordance, the amplitude of alpha-amino-3-hydroxy-5-methylisolazole-4-propionic acid (AMPA) but not of NMDA receptor-mediated currents was increased by corticosterone in stressed rats, over the entire voltage range. Corticosterone treatment also decreased the time to peak of AMPA currents, but this effect did not depend on prior stress exposure. The data indicate that following chronic stress exposure synaptic excitation of dentate granule cells may be enhanced when corticosterone levels rise. This enhanced synaptic flow could contribute to enhanced excitation of projection areas of the dentate gyrus, most notably the CA3 hippocampal region.

  11. Chronic intracerebral cannula can affect feeding behavior in the rat.

    PubMed

    Larue-Achagiotis, C; Louis-Sylvestre, J

    1989-04-01

    Intracerebral cannulae were placed in the lateral ventricle of rats. It was shown that the cannulae per se can affect feeding behavior. After recovery from surgery, rats displayed an unusual eating rate which consisted of very long, slow and large meals. This slow eating rate led to a modification of the circadian pattern; it induced a decrease in night-time and increase in day-time cumulative intakes. This phenomenon appeared when cannulae crossed the cortical motor area concerned with forelimb movements. Different stereotaxic coordinates had to be used in order to place cannulae in the lateral ventricle without disturbing the feeding pattern. This observation underlines the importance of recording feeding pattern before any surgery in any study of feeding behavior.

  12. Estradiol valerate elicits antidepressant-like effects in middle-aged female rats under chronic mild stress.

    PubMed

    Romano-Torres, Mónica; Fernández-Guasti, Alonso

    2010-03-01

    The purpose of this study was to analyze the antidepressant-like actions of estradiol valerate (1 or 2 mg/rat, single injection) or citalopram (5 or 10 mg/kg, chronically administered for 21 days) given independently or combined at low doses, to middle-aged ovariectomized female rats, as a model of human menopause. Animals were exposed to chronic mild stress, a model of depression that mimics anhedonia as revealed by diminished sucrose solution intake. Stressed rats decreased their sucrose preference 1 week after chronic stress and treatment with vehicle did not reverse this reduction. A single injection of estradiol valerate (2 mg/rat) produced an antidepressant-like action, evidenced as an increase in sucrose preference specific to stressed rats. Chronic citalopram (10 mg/kg) produced an antidepressant-like effect after 1 week. A single low-dose of estradiol valerate (1 mg/rat) did not potentiate or shorten the latency of action of chronic citalopram (5 mg/kg). These results reveal the antidepressant-like action of estrogens in middle-aged rats exposed to chronic stress. These data may be of importance for clinical depression in menopausal women. PMID:20168212

  13. Effect of chronic lithium administration on endothelium-dependent relaxation of rat mesenteric bed: role of nitric oxide.

    PubMed

    Afsharimani, Banafsheh; Moezi, Leila; Sadeghipour, Hamed; Rahimzadeh-Rofouyi, Bahareh; Nobakht, Maliheh; Sanatkar, Mehdi; Ghahremani, Mohammad Hosein; Dehpour, Ahmad R

    2007-10-01

    The mechanism of action of lithium, an effective treatment for bipolar disease, is still unknown. In this study, the mesenteric vascular beds of control rats and rats that were chronically treated with lithium were prepared by the McGregor method, and the mesenteric vascular bed vasorelaxation responses were examined. NADPH-diaphorase histochemistry was used to determine the activity of NOS (nitric oxide synthase) in mesenteric vascular beds. We demonstrated that ACh-induced vasorelaxation increased in the mesenteric vascular bed of rats treated with lithium. Acute No-nitro-L-arginine methyl ester (L-NAME) administration in the medium blocked ACh-induced vasorelaxation in the control group more effectively than in lithium-treated rats, while the vasorelaxant response to sodium nitroprusside, a NO donor, was not different between lithium-treated and control groups. Acute aminoguanidine administration blocked ACh-induced vasorelaxation of lithium-treated rats, but had no effect in the control rats. Furthermore, NOS activity, determined by NADPH-diaphorase staining, was significantly greater in the mesenteric vascular beds from chronic lithium-treated rats than in those from control rats. These data suggest that the enhanced ACh-induced endothelium-derived vasorelaxation in rat mesenteric bed from chronic lithium-treated rats might be associated with increased NOS activity, likely via iNOS. Simultaneous acute L-NAME and indomethacin administration suggests the possible upregulation of EDHF (endothelium-derived hyperpolarizing factor) in lithium-treated rats.

  14. Combined prenatal and chronic postnatal vitamin D deficiency in rats impairs prepulse inhibition of acoustic startle.

    PubMed

    Burne, Thomas H J; Féron, François; Brown, Jillanne; Eyles, Darryl W; McGrath, John J; Mackay-Sim, Alan

    2004-06-01

    There is growing evidence that 1,25-dihydroxyvitamin D3 is involved in normal brain development. The aim of this study was to examine the impact of prenatal and postnatal hypovitaminosis D on prepulse inhibition (PPI) of acoustic startle in adult rats. We compared six groups of rats: control rats with normal vitamin D throughout life and normal litter size (Litter); control rats with normal vitamin D but with a reduced litter size of two (Control); offspring from reduced litters of vitamin D deplete mothers who were repleted at birth (Birth), repleted at weaning (Weaning) or remained on a deplete diet until 10 weeks of age (Life); or control rats that were placed on a vitamin D-deficient diet from 5 to 10 weeks of age (Adult). All rats were tested in acoustic startle chambers at 5 and 10 weeks of age for acoustic startle responses and for PPI. There were no significant group differences at 5 weeks of age on the acoustic startle response or on PPI. At 10 weeks of age, rats in the Life group only had impaired PPI despite having normal acoustic startle responses. We conclude that combined prenatal and chronic postnatal hypovitaminosis D, but not early life hypovitaminosis D, alters PPI. PMID:15178159

  15. Cognitive dysfunction and histological findings in rats with chronic-stage contusion and diffuse axonal injury.

    PubMed

    Yamaki, T; Murakami, N; Iwamoto, Y; Sakakibara, T; Kobori, N; Ueda, S; Uwahodo, Y; Kikuchi, T

    1998-09-01

    The Morris water maze (MWM) technique is well known as a prominent method of evaluating learning acquisition and memory retention impairments in rats. We previously reported on a modified fluid percussion device that is able to consistently produce experimental cortical contusion (CC) and diffuse axonal injury (DAI) in separate groups of rats. The purpose of the present protocol is to evaluate the differences in learning acquisition and memory retention impairments between these two types of injured rats in the chronic stage using the MWM technique. CC and DAI rats are respectively induced by lateral and midline fluid percussion. We also compare the histological differences between these two different types of traumatic brain injury. The results show statistically significant differences in learning acquisition impairment between the sham and CC rats and between the sham and DAI rats. However, a difference in memory retention impairment was expected to be seen only between the sham and DAI rats. Histologically, the loss of CA3 pyramidal cells in the hippocampus was observed ipsilaterally in the CC and bilaterally in DAI. Neuronal cell loss was observed in bilaterally in layer II of the entorhinal cortex in DAI, but not in CC.

  16. Role of neovibsanin scaffold in preservation of spatial cognitive functions of rats with chronic epilepsy

    PubMed Central

    Dong, Li-Quan; Yan, Li-Li; Pan, Xu-Dong; Hu, Jin-Hua; Zhang, Jun-Wei

    2015-01-01

    The effect of neovibsanin scaffold (NS) on the spatial cognitive functions of rats with lobal cerebrovascular hypoperfusion was investigated. Rats were divided into long-term memory (LTM) and short-term memory (STM) groups with 15 rats in each group. The groups were subdivided into 3 groups: control group comprised of 5 rats without surgery, untreated group of 5 rats left without treatment after 2OV, and NS treatment group with 5 rats receiving 5 mg/kg daily for 12 weeks of 2VO operation. NS-treatment caused a marked decrease in the escape latency time and total distance travelled in the treatment group compared to untreated group which was evident from the working memory test. The animals of treatment group also showed significant improvement over that of untreated group in maze test performance. Furthermore, NS treatment also resulted in significant improvement in the probe memory test performance in treatment group compared to untreated group. These findings suggest that NS exhibits therapeutic effect on the spatial cognitive preservation in rats with chronic epilepsy. PMID:26339458

  17. Extracorporeal removal of uremic toxins: can we still do better?

    PubMed

    Eloot, Sunny; Ledebo, Ingrid; Ward, Richard A

    2014-03-01

    Improving outcomes by manipulating the prescription of renal replacement therapy to increase the removal of uremic toxins has had limited success. Failure to achieve better outcomes can be attributed to the heterogenic nature of uremic toxins, the complex distribution of some toxins in the body, and the predominant regimen of thee times weekly, in-center hemodialysis. This review summarizes the various mechanisms and kinetics of removal for the three major classes of uremic toxin-small water-soluble solutes, middle molecules, and protein-bound solutes-from both a theoretical and an experimental perspective. Taken together, the available data suggest that contemporary dialyzers are not a significant impediment to the removal of water-soluble uremic toxins, particularly when combined with commonly used blood and dialysis fluid flow rates and in online convective therapies. Enhancing the removal of those solutes will require a change in paradigm to longer and more frequent treatment sessions. Whether or not such a strategy also would improve the removal of protein-bound uremic toxins is less clear; that goal might require the development of different, more complex devices than those currently used for renal replacement therapy.

  18. Behavioral and neurochemical effects of chronic administration of reserpine and SKF-38393 in rats

    SciTech Connect

    Neisewander, J.L.; Lucki, I.; McGonigle, P. )

    1991-05-01

    Alterations in the density of dopamine receptor subtypes and behaviors mediated by the D1-selective agonist SKF-38393 were examined in rats treated chronically with reserpine, SKF-38393 or the combination of these drugs. Animals received either vehicle or reserpine (1 mg/kg s.c.) on days 1 to 28 and, in addition, half of each of these groups were treated with vehicle and half were treated with SKF-38393 (5-10 mg/kg s.c.) on days 15 to 29. Quantitative autoradiographic measurement of D1 receptors labeled with ({sup 3}H)SCH-23390 and D2 receptors labeled with ({sup 3}H)spiroperidol revealed that chronic administration of reserpine increased the density of both receptor subtypes in the nucleus accumbens and caudate-putamen, but not in the substantia nigra. Chronic administration of SKF-38393 alone did not alter D1 receptor density in any of these regions. However, chronic administration of the agonist in reserpinized animals decreased D1 receptor density in the nucleus accumbens, but not in the caudate-putamen or substantia nigra, demonstrating that this partial agonist can selectively down-regulate D1 receptors when endogenous dopaminergic tone is removed. The chronic drug treatments also altered behavioral responses. Chronic administration of SKF-38393 alone produced sensitization of the oral dyskinesia response elicited by a challenge injection of the agonist, but no significant change in the grooming response. Acute administration of SKF-38393 in rats treated with reserpine for 14 days produced stereotypy which was not altered after chronic administration of the agonist. Surprisingly, chronic administration of reserpine alone produced a spontaneous oral dyskinesia, which was blocked dose-dependently by the D2-selective antagonist spiroperidol. These findings are discussed in terms of their relevance to Parkinson's disease and tardive dyskinesia.

  19. Oxidation of ethanol in the rat brain and effects associated with chronic ethanol exposure.

    PubMed

    Wang, Jie; Du, Hongying; Jiang, Lihong; Ma, Xiaoxian; de Graaf, Robin A; Behar, Kevin L; Mason, Graeme F

    2013-08-27

    It has been reported that chronic and acute alcohol exposure decreases cerebral glucose metabolism and increases acetate oxidation. However, it remains unknown how much ethanol the living brain can oxidize directly and whether such a process would be affected by alcohol exposure. The questions have implications for reward, oxidative damage, and long-term adaptation to drinking. One group of adult male Sprague-Dawley rats was treated with ethanol vapor and the other given room air. After 3 wk the rats received i.v. [2-(13)C]ethanol and [1, 2-(13)C2]acetate for 2 h, and then the brain was fixed, removed, and divided into neocortex and subcortical tissues for measurement of (13)C isotopic labeling of glutamate and glutamine by magnetic resonance spectroscopy. Ethanol oxidation was seen to occur both in the cortex and the subcortex. In ethanol-naïve rats, cortical oxidation of ethanol occurred at rates of 0.017 ± 0.002 µmol/min/g in astroglia and 0.014 ± 0.003 µmol/min/g in neurons, and chronic alcohol exposure increased the astroglial ethanol oxidation to 0.028 ± 0.002 µmol/min/g (P = 0.001) with an insignificant effect on neuronal ethanol oxidation. Compared with published rates of overall oxidative metabolism in astroglia and neurons, ethanol provided 12.3 ± 1.4% of cortical astroglial oxidation in ethanol-naïve rats and 20.2 ± 1.5% in ethanol-treated rats. For cortical astroglia and neurons combined, the ethanol oxidation for naïve and treated rats was 3.2 ± 0.3% and 3.8 ± 0.2% of total oxidation, respectively. (13)C labeling from subcortical oxidation of ethanol was similar to that seen in cortex but was not affected by chronic ethanol exposure.

  20. Chronic behavioral and cognitive deficits in a rat survival model of paraoxon toxicity

    PubMed Central

    Deshpande, Laxmikant S.; Phillips, Kristin; Huang, Beverly; DeLorenzo, Robert J.

    2014-01-01

    Organophosphate (OP) compounds, including paraoxon (POX), are similar to nerve agents such as sarin. There is a growing concern that OP agents could be weaponized to cause mass civilian causalities. We have developed a rodent survival model of POX toxicity that is being used to evaluate chronic morbidity and to screen for medical countermeasures against severe OP exposure. It is well known that the survivors of nerve gas and chronic OP exposure exhibit neurobehavioral deficits such as mood changes, depression, and memory impairments. In this study we investigated whether animals surviving severe POX exposure exhibited long-term neurological impairments. POX exposure produced overt signs of cholinergic toxicity. Rats were rescued using an optimized atropine, 2-PAM and diazepam therapy. Surviving rats were studied using established behavioral assays for identifying symptoms of depression and memory impairment 3-months after POX exposure. In the forced swim test, POX rats exhibited increased immobility time indicative of a despair-like state. In the sucrose preference test, POX rats consumed significantly less sucrose water indicating anhedonia-like condition. POX rats also displayed increased anxiety as characterized by significantly lower performance in the open arm of the elevated plus maze. Further, when tested with a novel object recognition paradigm, POX rats exhibited a negative discrimination ratio indicative of impaired recognition memory. The results indicate that this model of survival from severe POX exposure can be employed to study some of the molecular bases for OP-induced chronic behavioral and cognitive comorbidities and develop therapies for their treatment. PMID:25172410

  1. Chronic dietary toxicity and carcinogenicity study with ammonium perfluorooctanoate in Sprague-Dawley rats.

    PubMed

    Butenhoff, John L; Kennedy, Gerald L; Chang, Shu-Ching; Olsen, Geary W

    2012-08-16

    In order to assess the potential chronic toxicity and tumorigenicity of ammonium perfluorooctanoate (APFO), a 2-year dietary study was conducted with male and female rats fed 30 ppm or 300 ppm (approximately 1.5 and 15 mg/kg). In males fed 300 ppm, mean body weights were lower across most of the test period and survival in these rats was greater than that seen either in the 30 ppm or the control group. Non-neoplastic effects were observed in liver in rats fed 300 ppm and included elevated liver weight, an increase in the incidence of diffuse hepatocellular hypertrophy, portal mononuclear cell infiltration, and mild hepatocellular vacuolation without an increase in hepatocellular necrosis. Mean serum activities of alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase were elevated up to three times the control means, primarily at the 300 ppm dose. A significant increase in Leydig cell tumors of the testes was seen in the males fed 300 ppm, and tumors of the liver and acinar pancreas, which are often observed in rats from chronic exposure to peroxisome proliferating agents, were not observed in this study. All other tumor types were those seen spontaneously in rats of this stock and age and were not associated with feeding of APFO. PMID:22531602

  2. Urinary folate excretion in chronic ethanol- and diet-treated rats

    SciTech Connect

    Collins, T.D.; McMartin, K.E.; Bairnsfather, L.

    1986-03-05

    Acute ethanol treatment of rats produces a marked increase in urinary folate excretion, which accumulates in correlation with the duration of ethanol treatment. In order to study the role of excess urinary folate excretion in the development of folate deficiency by chronic ethanol feeding, groups of male Sprague-Dawley rats were maintained for four months on one of the following liquid diets: ethanol, pair-fed control, ethanol minus folic acid, and pair-fed control minus folic acid. A fifth group was provided a control chow diet ad libitum. Blood ethanol levels were generally maintained between 80-150 mg/dl at various times of the day. Decrease in plasma and tissue folate levels occurred within four weeks in all liquid diet groups compared to chow rats and within two weeks for urinary folate levels. Greater effects were generally observed in both folate-deficient groups than in the control or ethanol group. Acute ethanol treatment of rats from the various diet groups produced increases in urinary folate excretion in all groups except the ethanol minus folic acid diet group. When the folate system of rats are compromised by dietary deprivation and/or chronic ethanol treatment, these results suggest that urinary folate excretion is greatly reduced as a conservation measure.

  3. Effect of chronic alcohol feeding on the ultrastructure of rat peripheral blood neutrophils: a morphometric study.

    PubMed

    Todorović, V; Koko, V; Lacković, V; Milin, J; Varagić, J

    1994-03-01

    Morphometric methods were used to analyze the ultrastructural characteristics of peripheral blood polymorphonuclear neutrophils (PMN) in 10 rats chronically consuming ethanol and 20 rats fed an isoenergetic standard diet (10 ad libitum and 10 pair fed control rats). Morphometric measurements were made, after a 4-month experimental period, of the following: the profile area of the cell, nucleus and cytoplasm; nucleus to cell profile area; volume density of the nucleus, cytoplasm, mitochondria, Golgi system, endoplasmic reticulum and cytoplasmic granules; number of mitochondria per cell profile; number of cytoplasmic granules per cell profile and per micron2 of cytoplasm, as well as the azurophilic to specific granule ratio and mean diameter of granules. A significant decrease in cell profile area and cytoplasm profile area was shown in ethanol-treated rats. The volume density of mitochondria and endoplasmic reticulum nearly doubled during ethanol abuse. The results also showed that there were highly significant effects of ethanol on the total number of cytoplasmic granules per cell. In addition, changes were observed in mitochondria such as clumping, elongation, swelling and disruption of cristae, as well as changes in the topographic distribution of granules in the cytoplasm such as registration of cytoplasmic areas with numerous granules and areas with a smaller number or without any granules. Some neutrophils of ethanol-treated rats had autophagic vacuoles. The results indicate some ultrastructural abnormalities of PMN in chronic experimental alcoholism that may be related to polymorphonuclear phagocyte dysfunction. PMID:8189745

  4. Serine dehydratase expression decreases in rat livers injured by chronic thioacetamide ingestion.

    PubMed

    López-Flores, Inmaculada; Barroso, Juan B; Valderrama, Raquel; Esteban, Francisco J; Martínez-Lara, Esther; Luque, Francisco; Peinado, M Angeles; Ogawa, Hirofumi; Lupiáñez, José A; Peragón, Juan

    2005-01-01

    Serine dehydratase (SerDH) is a gluconeogenic enzyme involved in the catabolism of serine, which is regulated by the composition of their diet and their hormonal status in rats. This study examines how chronic injury caused to the liver of rats by the ingestion of thioacetamide (TAA) affects SerDH protein, mRNA levels, enzyme kinetics and its tissue location. After 97 days' oral intake of TAA, the activity of SerDH at all substrate concentrations assayed was about 60% lower than in controls. No significant differences in Km values were found between the treated group and controls. Immunoblotting and immunohistochemistry revealed a significant reduction in the level of SerDH protein in the livers of the treated rats. SerDH was detected specifically in the periportal zone of the hepatic acinus and this location did not change in response to TAA treatment. The level of SerDH mRNA, quantified by reverse transcription and polymerase chain reaction, was significantly lower in treated rats than in the controls. The present findings suggest that the SerDH expression is rendered to be down regulatory during chronic liver injury induced by TAA. These results enhance our understanding about the biochemical mechanisms implied in the control and integration of serine catabolism during liver injury in rat.

  5. Mesenchymal Stem Cells Improve Heart Rate Variability and Baroreflex Sensitivity in Rats with Chronic Heart Failure

    PubMed Central

    de Morais, Sharon Del Bem Velloso; da Silva, Luiz Eduardo Virgilio; Lataro, Renata Maria; Silva, Carlos Alberto Aguiar; de Oliveira, Luciano Fonseca Lemos; de Carvalho, Eduardo Elias Vieira; Simões, Marcus Vinicius; da Silva Meirelles, Lindolfo; Fazan, Rubens

    2015-01-01

    Heart failure induced by myocardial infarct (MI) attenuates the heart rate variability (HRV) and baroreflex sensitivity, which are important risk factors for life-threatening cardiovascular events. Therapies with mesenchymal stem cells (MSCs) have shown promising results after MI. However, the effects of MSCs on hemodynamic (heart rate and arterial pressure) variability and baroreflex sensitivity in chronic heart failure (CHF) following MI have not been evaluated thus far. Male Wistar rats received MSCs or saline solution intravenously 1 week after ligation of the left coronary artery. Control (noninfarcted) rats were also evaluated. MI size was assessed using single-photon emission computed tomography (SPECT). The left ventricular ejection fraction (LVEF) was evaluated using radionuclide ventriculography. Four weeks after MSC injection, the animals were anesthetized and instrumented for chronic ECG recording and catheters were implanted in the femoral artery to record arterial pressure. Arterial pressure and HRVs were determined in time and frequency domain (spectral analysis) while HRV was also examined using nonlinear methods: DFA (detrended fluctuation analysis) and sample entropy. The initial MI size was the same among all infarcted rats but was reduced by MSCs. CHF rats exhibited increased myocardial interstitial collagen and sample entropy combined with the attenuation of the following cardiocirculatory parameters: DFA indices, LVEF, baroreflex sensitivity, and HRV. Nevertheless, MSCs hampered all these alterations, except the LVEF reduction. Therefore, 4 weeks after MSC therapy was applied to CHF rats, MI size and myocardial interstitial fibrosis decreased, while baroreflex sensitivity and HRV improved. PMID:26059001

  6. The effect of chronic ethanol on glutamate binding in human and rat brain

    SciTech Connect

    Cummins, J.T.; Sack, M.; von Hungen, K. Univ. of California School of Medicine, Los Angeles )

    1990-01-01

    Quantitative autoradiographic techniques demonstrate that chronic alcohol administration causes a decrease in ({sup 3}H)-glutamate binding to hippocampal N-methyl-D-aspartate (NMDA) receptors. A 14% decrease in ({sup 3}H)-glutamate binding in the hippocampal CA{sub 1} region is seen both in the rat after five days of ethanol administration and in postmortem hippocampal tissues from alcoholics. In the rat, 24 hr ethanol withdrawal values are intermediate between control and alcohol binding levels. There was no significant effect of ethanol on ({sup 3}H)-glutamate binding in the cortex or caudate.

  7. Neuroinflammation and Behavior in HIV-1 Transgenic Rats Exposed to Chronic Adolescent Stress

    PubMed Central

    Rowson, Sydney A.; Harrell, Constance S.; Bekhbat, Mandakh; Gangavelli, Apoorva; Wu, Matthew J.; Kelly, Sean D.; Reddy, Renuka; Neigh, Gretchen N.

    2016-01-01

    Highly active antiretroviral therapy (HAART) has improved prognosis for people living with HIV (PLWH) and dramatically reduced the incidence of AIDS. However, even when viral load is controlled, PLWH develop psychiatric and neurological disorders more frequently than those living without HIV. Adolescents with HIV are particularly susceptible to the development of psychiatric illnesses and neurocognitive impairments. While both psychiatric and neurocognitive disorders have been found to be exacerbated by stress, the extent to which chronic stress and HIV-1 viral proteins interact to impact behavior and relevant neuroinflammatory processes is unknown. Determination of the individual contributions of stress and HIV to neuropsychiatric disorders is heavily confounded in humans. In order to isolate the influence of HIV-1 proteins and chronic stress on behavior and neuroinflammation, we employed the HIV-1 transgenic (Tg) rat model, which expresses HIV-1 proteins with a gag and pol deletion, allowing for viral protein expression without viral replication. This Tg line has been characterized as a model of HAART-controlled HIV-1 infection due to the lack of viral replication but continued presence of HIV-1 proteins. We exposed male and female adolescent HIV-1 Tg rats to a mixed-modality chronic stress paradigm consisting of isolation, social defeat and restraint, and assessed behavior, cerebral vascularization, and neuroinflammatory endpoints. Stress, sex, and presence of the HIV-1 transgene impacted weight gain in adolescent rats. Female HIV-1 Tg rats showed decreases in central tendency during the light cycle in the open field regardless of stress exposure. Both male and female HIV-1 Tg rats exhibited decreased investigative behavior in the novel object recognition task, but no memory impairments. Adolescent stress had no effect on the tested behaviors. Microglia in female HIV-1 Tg rats exhibited a hyper-ramified structure, and gene expression of complement factor B was

  8. Chronic mild stress generates clear depressive but ambiguous anxiety-like behaviour in rats.

    PubMed

    Kompagne, Hajnalka; Bárdos, György; Szénási, Gábor; Gacsályi, István; Hársing, László G; Lévay, György

    2008-11-21

    A 3-week chronic mild stress (CMS) protocol decreased sucrose preference of rats and increased immobility in the forced swim test. It also induced social avoidance and increased grooming, but acted as if reducing anxiety in the plus-maze. Sucrose preference and social avoidance, but not other measures of the behaviour, showed significant correlation. We conclude that CMS-induced depression-like behaviour is associated with social avoidance, a seemingly anxiety-related measure, but not with other anxiety-like traits in rats.

  9. Neuroinflammation and Behavior in HIV-1 Transgenic Rats Exposed to Chronic Adolescent Stress.

    PubMed

    Rowson, Sydney A; Harrell, Constance S; Bekhbat, Mandakh; Gangavelli, Apoorva; Wu, Matthew J; Kelly, Sean D; Reddy, Renuka; Neigh, Gretchen N

    2016-01-01

    Highly active antiretroviral therapy (HAART) has improved prognosis for people living with HIV (PLWH) and dramatically reduced the incidence of AIDS. However, even when viral load is controlled, PLWH develop psychiatric and neurological disorders more frequently than those living without HIV. Adolescents with HIV are particularly susceptible to the development of psychiatric illnesses and neurocognitive impairments. While both psychiatric and neurocognitive disorders have been found to be exacerbated by stress, the extent to which chronic stress and HIV-1 viral proteins interact to impact behavior and relevant neuroinflammatory processes is unknown. Determination of the individual contributions of stress and HIV to neuropsychiatric disorders is heavily confounded in humans. In order to isolate the influence of HIV-1 proteins and chronic stress on behavior and neuroinflammation, we employed the HIV-1 transgenic (Tg) rat model, which expresses HIV-1 proteins with a gag and pol deletion, allowing for viral protein expression without viral replication. This Tg line has been characterized as a model of HAART-controlled HIV-1 infection due to the lack of viral replication but continued presence of HIV-1 proteins. We exposed male and female adolescent HIV-1 Tg rats to a mixed-modality chronic stress paradigm consisting of isolation, social defeat and restraint, and assessed behavior, cerebral vascularization, and neuroinflammatory endpoints. Stress, sex, and presence of the HIV-1 transgene impacted weight gain in adolescent rats. Female HIV-1 Tg rats showed decreases in central tendency during the light cycle in the open field regardless of stress exposure. Both male and female HIV-1 Tg rats exhibited decreased investigative behavior in the novel object recognition task, but no memory impairments. Adolescent stress had no effect on the tested behaviors. Microglia in female HIV-1 Tg rats exhibited a hyper-ramified structure, and gene expression of complement factor B was

  10. Mulberry leaf extract restores arterial pressure in streptozotocin-induced chronic diabetic rats.

    PubMed

    Naowaboot, Jarinyaporn; Pannangpetch, Patchareewan; Kukongviriyapan, Veerapol; Kukongviriyapan, Upa; Nakmareong, Saowanee; Itharat, Arunporn

    2009-08-01

    Free radical-induced vascular dysfunction plays a key role in the pathogenesis of vascular disease found in chronic diabetic patients. Morus alba (MA) leaf extract is promoted for good health especially in diabetic patients. Interestingly, antidiabetic and antioxidant activities of MA have been reported in experimental animals. Thus, the hypothesis of this study was that the long-term treatment with MA could improve vascular reactivity of chronic diabetic rats. To test this hypothesis, we examined the effect of long-term treatment with MA on the vascular responses to vasoactive agents in streptozotocin-induced chronic diabetic rats. The diabetic rats were either orally administered with distilled water, MA (0.25, 0.5 and 1 g/kg per day) or subcutaneously injected with insulin (4 U/kg per day) for 8 weeks. After each treatment, the fasting blood glucose, blood pressure, vascular responses to vasoactive agents and tissue malondialdehyde were examined. Morus alba at the doses of 0.5 and 1 g/kg, which significantly reduced blood glucose level, also significantly decreased the high blood pressure in diabetic rats. Vascular responses of the chronic diabetic rats to vasodilators, acetylcholine (3-30 nmol/kg) and sodium nitroprusside (1-10 nmol/kg) were significantly suppressed by 26% to 44% and 45% to 77% respectively, whereas those to vasoconstrictor, phenylephrine (0.01-0.1 micromol/kg) were significantly increased by 23% to 38% as compared to normal rats. Interestingly, the administration of 0.5 and 1 g/kg MA or 4 U/kg insulin significantly restored the vascular reactivities of diabetic rats. Moreover, 8 weeks of diabetes resulted in the elevation of malondialdehyde content in tissues (liver, kidney, heart, and aorta), and MA treatment significantly lessened this increase. These results provide the first evidence for the efficacy of MA in restoring the vascular reactivity of diabetic rats, the mechanism of which may associate with the alleviation of oxidative stress

  11. Chronic ethanol consumption in rats produces opioid antinociceptive tolerance through inhibition of mu opioid receptor endocytosis.

    PubMed

    He, Li; Whistler, Jennifer L

    2011-01-01

    It is well known that the mu-opioid receptor (MOR) plays an important role in the rewarding properties of ethanol. However, it is less clear how chronic ethanol consumption affects MOR signaling. Here, we demonstrate that rats with prolonged voluntary ethanol consumption develop antinociceptive tolerance to opioids. Signaling through the MOR is controlled at many levels, including via the process of endocytosis. Importantly, agonists at the MOR that promote receptor endocytosis, such as the endogenous peptides enkephalin and β-endorphin, show a reduced propensity to promote antinociceptive tolerance than do agonists, like morphine, which do not promote receptor endocytosis. These observations led us to examine whether chronic ethanol consumption produced opioid tolerance by interfering with MOR endocytosis. Indeed, here we show that chronic ethanol consumption inhibits the endocytosis of MOR in response to opioid peptide. This loss of endocytosis was accompanied by a dramatic decrease in G protein coupled receptor kinase 2 (GRK2) protein levels after chronic drinking, suggesting that loss of this component of the trafficking machinery could be a mechanism by which endocytosis is lost. We also found that MOR coupling to G-protein was decreased in ethanol-drinking rats, providing a functional explanation for loss of opioid antinociception. Together, these results suggest that chronic ethanol drinking alters the ability of MOR to endocytose in response to opioid peptides, and consequently, promotes tolerance to the effects of opioids.

  12. Establishment of a rat model of chronic thoracolumbar cord compression with a flat plastic screw.

    PubMed

    Sun, Yong; Zhang, Li-Hai; Fu, Yang-Mu; Li, Zhi-Rui; Liu, Jian-Heng; Peng, Jiang; Liu, Bin; Tang, Pei-Fu

    2016-06-01

    Previous studies of animal models of chronic mechanical compression of the spinal cord have mainly focused on cervical and thoracic lesions, but few studies have investigated thoracolumbar injury. The specific pathophysiological mechanism of chronic thoracolumbar cord injury has not yet been elucidated. The purpose of this study was to improve animal models of chronic thoracolumbar cord compression using the progressive screw. A custom-designed flat plastic screw was implanted in the spinal cord between thoracic vertebrae 12 and lumbar 1 of rats. The screw was tightened one complete turn (0.5 mm) every 7 days for 4 weeks to create different levels of chronic spinal cord compression. Following insertion of the screw, there was a significant decline in motor function of the hind limbs, and severe stenosis of micro-computed tomography parameters in the spinal cord. Cortical somatosensory evoked potential amplitudes were reduced remarkably, and latencies were prolonged at 30 minutes after surgery. The loss of motor neurons in the gray matter was marked. Demyelination and cavitation were observed in the white matter. An appropriate rat model of chronic thoracolumbar cord compression was successfully created using the progressive screw compression method, which simulated spinal cord compression injury. PMID:27482226

  13. Establishment of a rat model of chronic thoracolumbar cord compression with a flat plastic screw

    PubMed Central

    Sun, Yong; Zhang, Li-hai; Fu, Yang-mu; Li, Zhi-rui; Liu, Jian-heng; Peng, Jiang; Liu, Bin; Tang, Pei-fu

    2016-01-01

    Previous studies of animal models of chronic mechanical compression of the spinal cord have mainly focused on cervical and thoracic lesions, but few studies have investigated thoracolumbar injury. The specific pathophysiological mechanism of chronic thoracolumbar cord injury has not yet been elucidated. The purpose of this study was to improve animal models of chronic thoracolumbar cord compression using the progressive screw. A custom-designed flat plastic screw was implanted in the spinal cord between thoracic vertebrae 12 and lumbar 1 of rats. The screw was tightened one complete turn (0.5 mm) every 7 days for 4 weeks to create different levels of chronic spinal cord compression. Following insertion of the screw, there was a significant decline in motor function of the hind limbs, and severe stenosis of micro-computed tomography parameters in the spinal cord. Cortical somatosensory evoked potential amplitudes were reduced remarkably, and latencies were prolonged at 30 minutes after surgery. The loss of motor neurons in the gray matter was marked. Demyelination and cavitation were observed in the white matter. An appropriate rat model of chronic thoracolumbar cord compression was successfully created using the progressive screw compression method, which simulated spinal cord compression injury. PMID:27482226

  14. Effect of domperidone on ventilation and polycythemia after 5 weeks of chronic hypoxia in rats.

    PubMed

    Gamboa, J; Macarlupú, J L; Rivera-Chira, M; Monge-C, C; León-Velarde, F

    2003-04-15

    Chronically hypoxic humans and some mammals have attenuated ventilatory responses, which have been associated with high dopamine level in carotid bodies. Alveolar hypoventilation and blunted ventilatory response have been recognized to be at the basis of Chronic Mountain Sickness by generating arterial hypoxemia and polycythemia. To investigate whether dopamine antagonism could decrease the hemoglobin concentration by stimulating resting ventilation (VE) and/or hypoxic ventilatory response, 18 chronically hypoxic rats (5 weeks, PB=433 Torr) were studied with and without domperidone treatment (a peripheral dopamine antagonist). Acute and prolonged treatment significantly increased poikilocapnic ventilatory response to hypoxia (RVE ml/min/kg=VE at 0.1 FI(O(2))-VE at 0.21 FI(O(2))), from 506+/-36 to 697+/-48; and from 394+/-37 to 660+/-81, respectively. In addition, Domperidone treatment decreased hemoglobin concentration from 21.6+/-0.29 to 18.9+/-0.19 (P<0.01) in rats chronically exposed to hypobaric hypoxia. Our study suggests that the stimulant effect of D(2)-R blockade on ventilatory response to hypoxia seems to compensate the low hypoxic peripheral chemosensitivity after chronic exposure and the latter in turn decrease hemoglobin concentration.

  15. Chronic administration of anabolic steroids disrupts pubertal onset and estrous cyclicity in rats.

    PubMed

    Clark, Ann S; Kelton, Megan C; Whitney, Andrew C

    2003-02-01

    Use of anabolic-androgenic steroids (AASs) is becoming increasingly popular among adolescent girls, yet the effects of AASs on female physiology and development are not well understood. The present study compared the effects of chronic exposure to three individual AASs, stanozolol (0.05-5 mg/kg), 17alpha-methyltestosterone (0.5-5 mg/kg), and methandrostenolone (0.5-5 mg/kg) on the onset of puberty and estrous cyclicity in the rat. Female rats received daily injections of AASs for 30 days (Postnatal Day [PN] 21-51). Rats receiving the highest dose of each of the AASs (5 mg/kg) displayed vaginal opening at a younger age than rats receiving the oil vehicle. The day of first vaginal estrus was delayed in rats receiving stanozolol (5 mg/kg) or 17alpha-methyltestosterone (0.5-5 mg/kg) but not in rats receiving methandrostenolone. At the highest dose (5 mg/kg), each of the AASs reduced the incidence of regular estrous cyclicity during the treatment period. Concurrent administration (on PN21-51) of the androgen receptor antagonist, flutamide (10 mg/kg, twice daily), reversed the effects of 17alpha-methyltestosterone (5 mg/kg) on vaginal opening. Flutamide administration also eliminated the effects of stanozolol (5 mg/kg) and 17alpha-methyltestosterone (5 mg/kg) on the day of first vaginal estrus. In contrast, rats receiving flutamide and methandrostenolone (5 mg/kg) exhibited first vaginal estrus earlier than controls. The present results indicate that chronic exposure to AASs during development has deleterious effects on the female neuroendocrine axis and that these effects appear be mediated via multiple mechanisms. PMID:12533409

  16. Intestinal transport of hexoses in the rat following chronic heat exposure

    NASA Technical Reports Server (NTRS)

    Carpenter, M.; Musacchia, X. J.

    1979-01-01

    The study examines intestinal transport of sugars (D-glucose and D-galactose) in vitro and assesses organ maintenance in chronically heat-exposed rats. The results suggest that the response of intestinal absorption to heat exposure in the rat involves changes in intestinal weight and in glucose utilization. Despite the reduction in total intestinal weight, the ability of intestinal tissue to transport hexose per unit weight remains stable. Differences in intestinal weight and glucose utilization between pair-fed and heat-exposed animals suggest that the intestinal response to chronic heat exposure is not solely a function of the amount of food consumed. Alterations of hexose transport appear to be related to altered glucose metabolism and not altered transport capacity.

  17. Neuroplasticity-dependent and -independent mechanisms of chronic deep brain stimulation in stressed rats

    PubMed Central

    Bambico, F R; Bregman, T; Diwan, M; Li, J; Darvish-Ghane, S; Li, Z; Laver, B; Amorim, B O; Covolan, L; Nobrega, J N; Hamani, C

    2015-01-01

    Chronic ventromedial prefrontal cortex (vmPFC) deep brain stimulation (DBS) improves depressive-like behaviour in rats via serotonergic and neurotrophic-related mechanisms. We hypothesise that, in addition to these substrates, DBS-induced increases in hippocampal neurogenesis may also be involved. Our results show that stress-induced behavioural deficits in the sucrose preference test, forced swim test, novelty-suppressed feeding test (NSFT) and elevated plus maze were countered by chronic vmPFC DBS. In addition, stressed rats receiving stimulation had significant increases in hippocampal neurogenesis, PFC and hippocampal brain-derived neurotrophic factor levels. To block neurogenesis, stressed animals given DBS were injected with temozolomide. Such treatment reversed the anxiolytic-like effect of stimulation in the NSFT without significantly affecting performance in other behavioural tests. Taken together, our findings suggest that neuroplastic changes, including neurogenesis, may be involved in specific anxiolytic effects of DBS without affecting its general antidepressant-like response. PMID:26529427

  18. Unpredictable chronic stress in juvenile or adult rats has opposite effects, respectively, promoting and impairing resilience.

    PubMed

    Ricon, T; Toth, E; Leshem, M; Braun, K; Richter-Levin, G

    2012-01-01

    We evaluated the effects of early maternal deprivation (MD; age 7-14 days) alone or in combination with unpredictable chronic stress (UCS; MDUN; 28-84 days) on anxiety and learning in 90 days old adult rats. We hypothesized that exposure to both stressors (MDUN) would be more detrimental than exposure to one or neither. Unexpectedly, adult rats from the MDUN group did not differ from control animals, whereas adult MD animals exhibited impaired avoidance learning. We next investigated the effect of juvenile-onset (30-90 days) versus adult-onset (60-90 days) stress on avoidance learning in adulthood (90 days). We found that adult-onset chronic stress impaired avoidance learning and memory whereas juvenile-onset stress did not. Thus, the results again indicate that juvenile exposure to UCS induces resilience rather than impairment.

  19. Neurochemical Effects of Chronic Administration of Calcitriol in Rats

    PubMed Central

    Jiang, Pei; Zhang, Li-Hong; Cai, Hua-Lin; Li, Huan-De; Liu, Yi-Ping; Tang, Mi-Mi; Dang, Rui-Li; Zhu, Wen-Ye; Xue, Ying; He, Xin

    2014-01-01

    Despite accumulating data showing the various neurological actions of vitamin D (VD), its effects on brain neurochemistry are still far from fully understood. To further investigate the neurochemical influence of VD, we assessed neurotransmitter systems in the brain of rats following 6-week calcitriol (1,25-dihydroxyvitamin D) administration (50 ng/kg/day or 100 ng/kg/day). Both the two doses of calcitriol enhanced VDR protein level without affecting serum calcium and phosphate status. Rats treated with calcitriol, especially with the higher dose, exhibited elevated γ-aminobutyric acid (GABA) status. Correspondingly, the mRNA expression of glutamate decarboxylase (GAD) 67 was increased. 100 ng/kg of calcitriol administration also increased glutamate and glutamine levels in the prefrontal cortex, but did not alter glutamine synthetase (GS) expression. Additionally, calcitriol treatment promoted tyrosine hydroxylase (TH) and tryptophan hydroxylase 2 (TPH2) expression without changing dopamine and serotonin status. However, the concentrations of the metabolites of dopamine and serotonin were increased and the drug use also resulted in a significant rise of monoamine oxidase A (MAOA) expression, which might be responsible to maintain the homeostasis of dopaminergic and serotonergic neurotransmission. Collectively, the present study firstly showed the effects of calcitriol in the major neurotransmitter systems, providing new evidence for the role of VD in brain function. PMID:25533012

  20. Effect of acute and chronic tramadol on [3H]-5-HT uptake in rat cortical synaptosomes

    PubMed Central

    Giusti, Pietro; Buriani, Alessandro; Cima, Lorenzo; Lipartiti, Maria

    1997-01-01

    Tramadol hydrochloride is a centrally acting opioid analgesic, the efficacy and potency of which is only five to ten times lower than that of morphine. Opioid, as well as non-opioid mechanisms, may participate in the analgesic activity of tramadol. [3H]-5-hydroxytryptamine (5-HT) uptake in rat isolated cortical synaptosomes was studied in the presence of tramadol, desipramine, fluoxetine, methadone and morphine. Methadone and tramadol inhibited synaptosomal [3H]-5-HT uptake with apparent Kis of 0.27±0.04 and 0.76±0.04 μM, respectively. Morphine essentially failed to inhibit [3H]-5-HT uptake (Ki 0.50±0.30 M). Methadone, morphine and tramadol were active in the hot plate test with ED50s of 3.5, 4.3 and 31 mg kg−1, respectively. At the highest tested dose (80 mg kg−1) tramadol produced only 77±5.3% of the maximal possible effect. When [3H]-5-HT uptake was examined in synaptosomes prepared from rats 30 min after a single dose of morphine, methadone or tramadol, only tramadol (31 mg kg−1, s.c., equal to the ED50 in the hot plate test) and methadone (35 mg kg−1, s.c., equal to the ED90 in the hot plate test) decreased uptake. Animals were chronically treated for 15 days with increasing doses of tramadol or methadone (5 to 40 mg kg−1 and 15 to 120 mg kg−1, s.c., respectively). Twenty-four hours after the last drug injection, a challenge dose of methadone (35 mg kg−1, s.c.) or tramadol (31 mg kg−1, s.c.) was administered. [3H]-5-HT uptake was not affected in synaptosomes prepared from rats chronically-treated with methadone, whereas chronic tramadol was still able to reduce this parameter by 42%. Rats chronically-treated with methadone showed a significant increase in [3H]-5-HT uptake (190%) 72 h after drug withdrawal. In contrast, [3H]-5-HT uptake in rats chronically-treated with tramadol (110%) did not differ significantly from control animals. These results further support the hypothesis that [3H]-5-HT uptake

  1. A chronic inhalation toxicity/oncogenicity study of methylethylketoxime in rats and mice.

    PubMed

    Newton, P E; Wooding, W L; Bolte, H F; Derelanko, M J; Hardisty, J F; Rinehart, W E

    2001-12-01

    To evaluate the oncogenic potential of methylethylketoxime (MEKO), CD-1 mice (50/sex/group) and F-344 rats (50/sex/group) were coexposed 6 h/day, 5 days/wk for 18 mo (mice) or 26 mo (rats) via whole-body inhalation exposures to target vapor concentrations of 0, 15, 75, and 375 ppm (actual concentrations of 0, 15 +/- 1, 75 +/- 2, or 374 +/- 10 ppm). Satellite groups of rats and mice (10/sex/group/interval) were exposed for 12 mo (mice) and 3, 12, or 18 mo (rats) to evaluate chronic toxicity. Methyl ethyl ketone (MEK), a possible hydrolysis product of MEKO, was present at less than 1%. Treatment-related effects included increased body weight (male rats only), methemoglobin formation, hematology and clinical chemistry changes, increased liver weight, and increased spleen and testes weights (rats only). A high incidence of cataracts and corneal dystrophy occurred in both control and MEKO-exposed rats, with an earlier appearance and slightly higher incidence for these ocular lesions in MEKO-exposed animals compared to controls. Degenerative and reparative changes of the olfactory epithelium in the nasal turbinates, primarily limited to the dorsal meatus, occurred in both rats (75 and 374 ppm) and mice (15, 75, and 374 ppm). In addition, in the mice, liver changes included increased incidences of pigment in reticuloendothelial cells, centilobular hypertrophy, granulomatous inflammation, and a slightly increased incidence of necrosis (75 and 374 ppm). An increase in hepatocellular carcinomas occurred in male mice at 374 ppm. Additional MEKO-related findings in the rat included congestion of the spleen with pigment in reticuloendothelial cells and extramedullary hematopoiesis and a decreased incidence of lymphoreticular mononuclear cell leukemia. Effects observed in the liver of the rats included decreases in the incidence of both peribiliary fibrosis and hyperplasia/proliferation of the biliary duct, an increase of spongiosis hepatis in males, and an increase in the

  2. EXPERIMENTAL INDUCTION OF CHRONIC PULMONARY DISEASE IN GENETICALLY SUSCEPTIBLE RAT MODEL

    EPA Science Inventory



    Experimental induction of chronic pulmonary disease in genetically susceptible rat model. M.C.Schladweiler, BS 1, A.D.Ledbetter 1, K.E.Pinkerton, PhD 2, K.R.Smith, PhD 2, P.S.Gilmour, PhD 1, P.A.Evansky 1, D.L.Costa, ScD 1, W.P.Watkinson, PhD 1, J.P.Nolan 1 and U.P.Kodava...

  3. Chronic ethanol and nicotine interaction on rat tissue antioxidant defense system.

    PubMed

    Husain, K; Scott, B R; Reddy, S K; Somani, S M

    2001-10-01

    Ethanol consumption and cigarette smoking are common in societies worldwide and have been identified as injurious to human health. This study was undertaken to examine the interactive effects of chronic ethanol and nicotine consumption on the antioxidant defense system in different tissues of rat. Male Fisher-344 rats were divided into four groups of five animals each and treated for 6.5 weeks as follows: (1) Control rats were administered normal saline orally; (2) ethanol (20% [wt./vol.]) was given orally at a dose of 2 g/kg; (3) nicotine was administered subcutaneously at a dose of 0.1 mg/kg; and (4) a combination of ethanol plus nicotine was administered by the route and at the dose described above. The animals were killed 20 h after the last treatment, and liver, lung, kidney, and testes were isolated and analyzed. Chronic ingestion of ethanol resulted in a significant depletion of glutathione (GSH) content in liver, lung, and testes, whereas chronic administration of nicotine significantly depleted GSH content in liver and testes. The combination of ethanol plus nicotine resulted in a significant depletion of GSH content in liver, lung, and testes. Ethanol, nicotine, or a combination of ethanol plus nicotine significantly increased superoxide dismutase (SOD) activity in liver and decreased SOD activity in kidney. Ethanol, nicotine, or a combination of ethanol plus nicotine significantly decreased catalase (CAT) activity in liver and increased CAT activity in kidney and testes. Chronic ingestion of ethanol resulted in a significant decrease in glutathione peroxidase (GSH-Px) activity in liver and kidney, whereas a combination of ethanol plus nicotine increased GSH-Px activity in liver and decreased GSH-Px activity in kidney and testes. Ethanol, nicotine, or a combination of ethanol plus nicotine significantly increased lipid peroxidation, respectively, in liver. It is suggested that prolonged exposure to ethanol and nicotine produce similar, and in some cases

  4. [PROTEIN CONTENT CHANGES IN RATS' LIVER AND BRAIN UNDER CHRONIC ALCOHOL INTOXICATION].

    PubMed

    Raksha, N G; Savchuk, A N; Kharchenko, O I; Galenova, T I; Ostapchenko, L I

    2015-01-01

    An electrophoretic investigation of quantitative protein content in rat's' tissyes under chronic alcoholic intoxication has been done. It was shown the significant increase of protein content with molecular mass 55, 48-50, 43-45, 39-41 KDa and the decrease-of protein fractions with molecular mass 46-48, 34-35, 27-30, 16-18 KDa accordingly in liver and brain homogenates of experimental animals. PMID:26827457

  5. Effects of chronic and acute stress on rat behaviour in the forced-swim test.

    PubMed

    Suvrathan, Aparna; Tomar, Anupratap; Chattarji, Sumantra

    2010-11-01

    Stress and depression may share common neural plasticity mechanisms. Importantly, the development and reversal of stress-induced plasticity requires time. These temporal aspects, however, are not captured fully in the forced-swim test (FST), a behavioural model for testing antidepressant efficacy, used originally in naïve animals. The present study probed whether and how a rodent model of stress affects behaviour in the FST over time. We found that the intensity and duration of stress are critical in the development of depressive symptoms in male Wistar rats (n = 37) as tested in the FST. Chronic immobilization stress (2 h/day for 10 days) elicited a range of responses, from low to high values of immobility in the FST on day 1, and subsequent immobility on day 2 was inversely related to individual day 1 values. As a whole, chronically stressed rats did not exhibit any significant change in immobility either on day 1 or day 2 compared to control rats. However, climbing behaviour was reduced uniformly from day 1 to day 2, despite the differences in immobility. In contrast, a separate group of rats (n = 30) subjected to the same chronic stressor displayed a significant reduction in open-arm exploration in the elevated plus maze, indicative of a robust increase in anxiety-like behaviour. Furthermore, when the 10-day chronic stress paradigm was reduced to a single 2-h episode of immobilization stress, it triggered a uniform day 1 to day 2 increase in immobility, which was not persistent 10 days later. These results highlight a need for closer examination of the ways in which stress-induced modulation of behaviour in the FST may be used and interpreted in future studies aimed at exploring connections between stress and depression.

  6. Metabolic alterations induced by chronic heat exposure in the rat: the involvement of thyroid function.

    PubMed

    Rousset, B; Cure, M; Jordan, D; Kervran, A; Bornet, H; Mornex, R

    1984-05-01

    The effects of chronic exposure to high environmental temperature (34 degrees C) on T4 production rate, food-intake, growth-rate and resting metabolic rate were investigated in adult male rats. This study was designed to examine the extent of variations and possible relationships between these parameters. As compared to control rats of the same body weight kept at 25 degrees C, rats exposed to 34 degrees C for 3-4 weeks exhibited a retarded growth-rate: 2.3 vs 4.0 g/day, a reduced food-intake: 15.2 vs 23.2 g/day, a decreased T4 production-rate: 1.8 vs 2.7 micrograms/day and a decreased oxygen consumption: 4.0 vs 5.4 ml/min. Heat-exposure altered the 4 parameters to a similar extent. T4 supplementation (3 micrograms/day) which induced a decrease in plasma TSH concentration, did not restore a normal growth-rate in heat-exposed rats. The decreased food-intake of the heat-exposed rats was not associated with any significant changes in the daily pattern of variations of liver glycogen content, or in the mean daily levels of blood glucose or insulin. The ratio T3 to rT3 in plasma was not altered by chronic heat exposure. When rats which had been chronically exposed to heat (25 days at 34 degrees C) were exposed to 25 degrees C, growth-rate, food-intake and oxygen consumption rapidly increased to control values whereas the rate of T4 production remained low. It is concluded that (1) a decrease in thyroid hormone economy is not directly involved in the alterations of growth and energy expenditure in rats chronically exposed to heat, (2) heat exposure does not lead to the establishment of a fasted state resulting from a large reduction in voluntary food intake, (3) metabolic alterations induced by heat exposure are rapidly and completely reversible upon decreasing the environmental temperature.

  7. Environmental NO2 and CO Exposure: Ignored Factors Associated with Uremic Pruritus in Patients Undergoing Hemodialysis.

    PubMed

    Huang, Wen-Hung; Lin, Jui-Hsiang; Weng, Cheng-Hao; Hsu, Ching-Wei; Yen, Tzung-Hai

    2016-01-01

    Uremic pruritus (UP), also known as chronic kidney disease-associated pruritus, is a common and disabling symptom in patients undergoing maintenance hemodialysis (MHD). The pathogenesis of UP is multifactorial and poorly understood. Outdoor air pollution has well-known effects on the health of patients with allergic diseases through an inflammatory process. Air pollution-induced inflammation could occur in the skin and aggravate skin symptoms such as pruritus or impair epidermal barrier function. To assess the role of air pollutants, and other clinical variables on uremic pruritus (UP) in HD patients, we recruited 866 patients on maintenance HD. We analyzed the following variables for association with UP: average previous 12-month and 24-month background concentrations for nitrogen dioxide (NO2) and carbon monoxide (CO), and suspended particulate matter of <2.5 μm (PM2.5). In a multivariate logistic regression, hemodialysis duration, serum ferritin levels, low-density lipoprotein levels, and environmental NO2/CO levels were positively associated with UP, and serum albumin levels were negatively associated with UP. This cross-sectional study showed that air pollutants such as NO2 and CO might be associated with UP in patients with MHD. PMID:27507591

  8. Studies on Erythropoiesis in Uremic and Post-Transplant (Renal) Patients Utilizing Radioactive Iron and Chromium

    PubMed Central

    Farooki, M. S.; Kimber, R. W.

    1971-01-01

    The association of anemia with chronic renal disease is well known. The striking hematologic improvement following a successful renal allotransplantation led to the present study. Using radioactive 59Fe, ferrokinetic measurements were carried out in nine uremic patients (seven with and two without anemia), four post-allotransplant cases, three patients with iron deficiency anemia and a group of five normal subjects. Erythrocyte life-span was calculated by 51Cr-labelled, autotransfused red cells in all patients who had had transplants and in three patients with renal anemia. The results showed that in patients with renal anemia the plasma radioiron clearance was slightly delayed but the 59Fe incorporation into the circulating erythrocytes was significantly decreased. Red cell life-span was moderately shortened in two out of three uremic patients investigated. The findings constitute evidence of ineffective erythropoiesis in patients with renal anemia. By comparison, the four transplant patients showed normal 59Fe plasma clearance and red cell incorporation; the 51Cr erythrocyte survival was normal in all four patients. PMID:4931770

  9. Environmental NO2 and CO Exposure: Ignored Factors Associated with Uremic Pruritus in Patients Undergoing Hemodialysis

    PubMed Central

    Huang, Wen-Hung; Lin, Jui-Hsiang; Weng, Cheng-Hao; Hsu, Ching-Wei; Yen, Tzung-Hai

    2016-01-01

    Uremic pruritus (UP), also known as chronic kidney disease–associated pruritus, is a common and disabling symptom in patients undergoing maintenance hemodialysis (MHD). The pathogenesis of UP is multifactorial and poorly understood. Outdoor air pollution has well-known effects on the health of patients with allergic diseases through an inflammatory process. Air pollution–induced inflammation could occur in the skin and aggravate skin symptoms such as pruritus or impair epidermal barrier function. To assess the role of air pollutants, and other clinical variables on uremic pruritus (UP) in HD patients, we recruited 866 patients on maintenance HD. We analyzed the following variables for association with UP: average previous 12-month and 24-month background concentrations for nitrogen dioxide (NO2) and carbon monoxide (CO), and suspended particulate matter of <2.5 μm (PM2.5). In a multivariate logistic regression, hemodialysis duration, serum ferritin levels, low-density lipoprotein levels, and environmental NO2/CO levels were positively associated with UP, and serum albumin levels were negatively associated with UP. This cross-sectional study showed that air pollutants such as NO2 and CO might be associated with UP in patients with MHD. PMID:27507591

  10. Environmental NO2 and CO Exposure: Ignored Factors Associated with Uremic Pruritus in Patients Undergoing Hemodialysis

    NASA Astrophysics Data System (ADS)

    Huang, Wen-Hung; Lin, Jui-Hsiang; Weng, Cheng-Hao; Hsu, Ching-Wei; Yen, Tzung-Hai

    2016-08-01

    Uremic pruritus (UP), also known as chronic kidney disease–associated pruritus, is a common and disabling symptom in patients undergoing maintenance hemodialysis (MHD). The pathogenesis of UP is multifactorial and poorly understood. Outdoor air pollution has well-known effects on the health of patients with allergic diseases through an inflammatory process. Air pollution–induced inflammation could occur in the skin and aggravate skin symptoms such as pruritus or impair epidermal barrier function. To assess the role of air pollutants, and other clinical variables on uremic pruritus (UP) in HD patients, we recruited 866 patients on maintenance HD. We analyzed the following variables for association with UP: average previous 12-month and 24-month background concentrations for nitrogen dioxide (NO2) and carbon monoxide (CO), and suspended particulate matter of <2.5 μm (PM2.5). In a multivariate logistic regression, hemodialysis duration, serum ferritin levels, low-density lipoprotein levels, and environmental NO2/CO levels were positively associated with UP, and serum albumin levels were negatively associated with UP. This cross-sectional study showed that air pollutants such as NO2 and CO might be associated with UP in patients with MHD.

  11. Preventing dyslipidemia by Chlorella pyrenoidosa in rats and hamsters after chronic high fat diet treatment.

    PubMed

    Cherng, Jong-Yuh; Shih, Mei-Fen

    2005-05-13

    The effects of Chlorella pyrenoidosa on serum lipid profiles, after concomitant long-term treatment of high-fat diet (HFD) in rats and hamsters was studied. Wistar rats and Syrian hamsters were fed with or without various concentrations of Chlorella pyrenoidosa contained high-fat diet (CHFD) for 2, 4 and 8 weeks prior to assay of serum lipids. Fasting triglycerides, total cholesterol, and LDL cholesterol as well as HDL cholesterol levels in high-fat diet treated rats and hamster were determined. Results showed that triglycerides, total cholesterol and LDL cholesterol levels in HFD treated rats and hamsters were increased from the normal rodent diet (NRD) treated controls after 2, 4, and 8-week treatments. However, the presence of Chlorella pyrenoidosa in high-fat diets significantly decreased the levels of triglycerides, total cholesterol and LDL cholesterol with comparison to HFD group in rats and hamsters. The total cholesterol/HDL ratios, an indication of occurrence of coronary heart disease, were decreased in all CHFD treated grouped rats and hamsters which suggests administration of Chlorella pyrenoidosa could lower the occurring risk of heart diseases. In conclusion, Chlorella pyrenoidosa has the ability to prevent dyslipidemia in chronic high-fat fed animals and could be potential in use to prevent intestinal absorption of redundant lipid from our daily intake and subsequently to prevent hyperlipidemia as well as atherosclerosis. PMID:15850594

  12. Assessment of oxidative parameters in rat spinal cord after chronic constriction of the sciatic nerve.

    PubMed

    Goecks, Cristina S B; Horst, Andréa; Moraes, Maira S; Scheid, Taína; Kolberg, Carolina; Belló-Klein, Adriane; Partata, Wania A

    2012-09-01

    Although reactive oxygen species (ROS) are involved in neuropathic pain, the direct relationship between these species and chronic constriction of sciatic nerve (CCI) has not been studied in spinal cord. Thus, this study induced CCI in rats and these animals were sacrificed 3 and 10 days after the surgical procedure to determine the superoxide dismutase (SOD) and catalase activities, as well as ascorbic acid, hydrogen peroxide (H(2)O(2)) and lipid hydroperoxide levels in lumbosacral spinal cord. Von Frey Hair and hot plate tests were performed to assess the degree of mechanical and thermal hyperalgesia at days 0, 3 and 10. The results showed that CCI significantly induced mechanical and thermal hyperalgesia at days 3 and 10. Parallel there was increase in spinal cord lipid hydroperoxide at days 3 and 10 in rats submitted to CCI. In Sham rats a significant increase in this parameter occurred at day 10. H(2)O(2) decreased at day 10 only in CCI group. SOD activity was decreased in Sham and CCI groups at day 3, while catalase activity was increased in CCI rats at days 3 and 10. Ascorbic acid levels were reduced only in CCI rats at day 3. Although the role of such changes is unclear, many were not specific to neuropathic pain and the differences could be related to different degrees of central sensitization in Sham and CCI rats. PMID:22674084

  13. Hemolytic uremic syndrome in an infant following Bordetella pertussis infection.

    PubMed

    Pela, I; Seracini, D; Caprioli, A; Castelletti, F; Giammanco, A

    2006-08-01

    Reported here is the case of a 6-week-old female infant with a severe Bordetella pertussis infection requiring supportive pressure-positive ventilation in the intensive care unit. After being discharged from the intensive care unit, she developed hemolytic anemia, thrombocytopenia and acute renal failure, which suggested a diagnosis of hemolytic uremic syndrome. The clinical outcome was favorable with no renal consequences. This case suggests there may be a direct cause-effect relationship between B. pertussis infection and hemolytic uremic syndrome. PMID:16871374

  14. Dysregulation of Glucose Homeostasis Following Chronic Exogenous Administration of Leptin in Healthy Sprague-Dawley Rats

    PubMed Central

    Wjidan, Khalil; Ibrahim, Effendi; Caszo, Brinnell; Gnanou, Justin

    2015-01-01

    Introduction Impaired glucose utilization is seen in chronic hyperleptinaemia associated conditions such as obesity and type 2 diabetes mellitus. It is unclear if this impaired glucose utilization is due to the effect of persistent hyperleptinaemia on insulin secretion from the beta cells of pancreas. Aim To examine the effects of chronic leptin administration on plasma glucose regulation in rats. Materials and Methods Glucose challenge curves were plotted for male Sprague-Dawley rats treated with either normal saline (Control; n=8) or subcutaneous leptin injection for 42 days (60 μg/kg body weight/day; n=8). Plasma glucose and plasma insulin levels were measured at 0, 5, 10, 15, 20 and 25 minutes after glucose challenege. Skeletal muscle tissue was collected at the end of a glucose challenge for glucose transporter-4 protein content, insulin receptor and glucose transporter-4 mRNA expression. Data were analysed using repeated measures and one-way ANOVA with post-hoc analysis. Results Chronic leptin treatment caused significantly higher fasting insulin level. Post glucose challenge, there was a significant increase in blood glucose levels and insulin level in the leptin treated rats. There was no significant difference in the skeletal muscle glucose transporter-4 content. However, leptin treated rats showed decreased mRNA expression of Insulin Receptor and glucose transporter-4 in the skeletal muscle. Conclusion Leptin administration for 42 days caused hyperinsulinaemia and decreased the expression of insulin receptors in insulin sensitive tissues leading to the development of an insulin resistance-like state in the rats. PMID:26816939

  15. Psychomotor Vigilance Task Performance During and Following Chronic Sleep Restriction in Rats

    PubMed Central

    Deurveilher, Samuel; Bush, Jacquelyn E.; Rusak, Benjamin; Eskes, Gail A.; Semba, Kazue

    2015-01-01

    Study Objectives: Chronic sleep restriction (CSR) impairs sustained attention in humans, as commonly assessed with the psychomotor vigilance task (PVT). To further investigate the mechanisms underlying performance deficits during CSR, we examined the effect of CSR on performance on a rat version of PVT (rPVT). Design: Adult male rats were trained on a rPVT that required them to press a bar when they detected irregularly presented, brief light stimuli, and were then tested during CSR. CSR consisted of 100 or 148 h of continuous cycles of 3-h sleep deprivation (using slowly rotating wheels) alternating with a 1-h sleep opportunity (3/1 protocol). Measurements and Results: After 28 h of CSR, the latency of correct responses and the percentages of lapses and omissions increased, whereas the percentage of correct responses decreased. Over 52–148 h of CSR, all performance measures showed partial or nearly complete recovery, and were at baseline levels on the first or second day after CSR. There were large interindividual differences in the magnitude of performance impairment during CSR, suggesting differential vulnerability to the effects of sleep loss. Wheel-running controls showed no changes in performance. Conclusions: A 28-h period of the 3/1 chronic sleep restriction (CSR) protocol disrupted performance on a sustained attention task in rats, as sleep deprivation does in humans. Performance improved after longer periods of CSR, suggesting allostatic adaptation, contrary to some reports of progressive deterioration in psychomotor vigilance task performance during CSR in humans. However, as observed in humans, there were individual differences among rats in the vulnerability of their attention performance to CSR. Citation: Deurveilher S, Bush JE, Rusak B, Eskes GA, Semba K. Psychomotor vigilance task performance during and following chronic sleep restriction in rats. SLEEP 2015;38(4):515–528. PMID:25515100

  16. Chronic pramipexole treatment increases tolerance for sucrose in normal and ventral tegmental lesioned rats

    PubMed Central

    Dardou, David; Chassain, Carine; Durif, Franck

    2015-01-01

    The loss of dopamine neurons observed in Parkinson's disease (PD) elicits severe motor control deficits which are reduced by the use of dopamine agonists. However, recent works have indicated that D3-preferential agonists such as pramipexole can induce impulse control disorders (ICDs) such as food craving or compulsive eating. In the present study, we performed an intermittent daily feeding experiment to assess the effect of chronic treatment by pramipexole and VTA bilateral lesion on tolerance for sucrose solution. The impact of such chronic treatment on spontaneous locomotion and spatial memory was also examined. Changes in sucrose tolerance could indicate the potential development of a change in food compulsion or addiction related to the action of pramipexole. Neither the bilateral lesion of the VTA nor chronic treatment with pramipexole altered the spontaneous locomotion or spatial memory in rats. Rats without pramipexole treatment quickly developed a stable intake of sucrose solution in the 12 h access phase. On the contrary, when under daily pramipexole treatment, rats developed a stronger and ongoing escalation of their sucrose solution intakes. In addition, we noted that the change in sucrose consumption was sustained by an increase of the expression of the Dopamine D3 receptor in the core and the shell regions of the nucleus accumbens. The present results may suggest that long-term stimulation of the Dopamine D3 receptor in animals induces a strong increase in sucrose consumption, indicating an effect of this receptor on certain pathological aspects of food eating. PMID:25610366

  17. Chronic hypoxia-induced alterations in mitochondrial energy metabolism are not reversible in rat heart ventricles.

    PubMed

    Nouette-Gaulain, Karine; Biais, Matthieu; Savineau, Jean-Pierre; Marthan, Roger; Mazat, Jean-Pierre; Letellier, Thierry; Sztark, François

    2011-01-01

    Chronic hypoxia alters mitochondrial energy metabolism. In the heart, oxidative capacity of both ventricles is decreased after 3 weeks of chronic hypoxia. The aim of this study was to evaluate the reversal of these metabolic changes upon normoxia recovery. Rats were exposed to a hypobaric environment for 3 weeks and then subjected to a normoxic environment for 3 weeks (normoxia-recovery group) and compared with rats maintained in a normoxic environment (control group). Mitochondrial energy metabolism was differentially examined in both left and right ventricles. Oxidative capacity (oxygen consumption and ATP synthesis) was measured in saponin-skinned fibers. Activities of mitochondrial respiratory chain complexes and antioxidant enzymes were measured on ventricle homogenates. Morphometric analysis of mitochondria was performed on electron micrographs. In normoxia-recovery rats, oxidative capacities of right ventricles were decreased in the presence of glutamate or palmitoyl carnitine as substrates. In contrast, oxidation of palmitoyl carnitine was maintained in the left ventricle. Enzyme activities of complexes III and IV were significantly decreased in both ventricles. These functional alterations were associated with a decrease in numerical density and an increase in size of mitochondria. Finally, in the normoxia-recovery group, the antioxidant enzyme activities (catalase and glutathione peroxidase) increased. In conclusion, alterations of mitochondrial energy metabolism induced by chronic hypoxia are not totally reversible. Reactive oxygen species could be involved and should be investigated under such conditions, since they may represent a therapeutic target.

  18. Chronic pramipexole treatment increases tolerance for sucrose in normal and ventral tegmental lesioned rats.

    PubMed

    Dardou, David; Chassain, Carine; Durif, Franck

    2014-01-01

    The loss of dopamine neurons observed in Parkinson's disease (PD) elicits severe motor control deficits which are reduced by the use of dopamine agonists. However, recent works have indicated that D3-preferential agonists such as pramipexole can induce impulse control disorders (ICDs) such as food craving or compulsive eating. In the present study, we performed an intermittent daily feeding experiment to assess the effect of chronic treatment by pramipexole and VTA bilateral lesion on tolerance for sucrose solution. The impact of such chronic treatment on spontaneous locomotion and spatial memory was also examined. Changes in sucrose tolerance could indicate the potential development of a change in food compulsion or addiction related to the action of pramipexole. Neither the bilateral lesion of the VTA nor chronic treatment with pramipexole altered the spontaneous locomotion or spatial memory in rats. Rats without pramipexole treatment quickly developed a stable intake of sucrose solution in the 12 h access phase. On the contrary, when under daily pramipexole treatment, rats developed a stronger and ongoing escalation of their sucrose solution intakes. In addition, we noted that the change in sucrose consumption was sustained by an increase of the expression of the Dopamine D3 receptor in the core and the shell regions of the nucleus accumbens. The present results may suggest that long-term stimulation of the Dopamine D3 receptor in animals induces a strong increase in sucrose consumption, indicating an effect of this receptor on certain pathological aspects of food eating. PMID:25610366

  19. Chronic alpha-tocopherol supplementation in rats does not ameliorate either chronic or acute alcohol-induced changes in muscle protein metabolism.

    PubMed

    Koll, Michael; Beeso, Julie A; Kelly, Frank J; Simanowski, Ulrich A; Seitz, Helmut K; Peters, Timothy J; Preedy, Victor R

    2003-03-01

    Chronic alcohol muscle disease is characterized by reduced skeletal muscle mass precipitated by acute reduction in protein synthesis. The pathogenic mechanisms remain obscure, but several lines of evidence suggest that increased oxidative stress occurs in muscle in response to alcohol and this may be associated with impaired alpha-tocopherol status. Potentially, this implies a therapeutic role for alpha-tocopherol, especially as we have shown that supplemental alpha-tocopherol may increase the rate of protein synthesis in normal rats [Reilly, Patel, Peters and Preedy (2000) J. Nutr. 130, 3045-3049]. We investigated the therapeutic effect of alpha-tocopherol on plantaris muscle protein synthesis in rats treated either acutely, chronically or chronically+acutely with ethanol. Protein synthesis rates were measured with a flooding dose of L-[4-(3)H]phenylalanine. Protein, RNA and DNA contents were determined by standard laboratory methods. Ethanol caused defined metabolic changes in muscle, including decreased protein, RNA and DNA contents in chronically treated rats. In acute or chronic+acute studies, ethanol suppressed fractional rates of protein synthesis. alpha-Tocopherol supplementation did not ameliorate the effects of either acute, chronic or chronic+acute alcohol on plantaris muscle protein content or rates of protein synthesis. In control animals (not treated with alcohol), alpha-tocopherol supplementation decreased muscle protein content owing to increases in protein turnover (both synthesis and degradation). alpha-Tocopherol supplementation is not protective against the deleterious effects of alcohol on protein metabolism in skeletal muscle.

  20. Chronic sleep disturbance impairs glucose homeostasis in rats.

    PubMed

    Barf, R Paulien; Meerlo, Peter; Scheurink, Anton J W

    2010-01-01

    Epidemiological studies have shown an association between short or disrupted sleep and an increased risk for metabolic disorders. To assess a possible causal relationship, we examined the effects of experimental sleep disturbance on glucose regulation in Wistar rats under controlled laboratory conditions. Three groups of animals were used: a sleep restriction group (RS), a group subjected to moderate sleep disturbance without restriction of sleep time (DS), and a home cage control group. To establish changes in glucose regulation, animals were subjected to intravenous glucose tolerance tests (IVGTTs) before and after 1 or 8 days of sleep restriction or disturbance. Data show that both RS and DS reduce body weight without affecting food intake and also lead to hyperglycemia and decreased insulin levels during an IVGTT. Acute sleep disturbance also caused hyperglycemia during an IVGTT, yet, without affecting the insulin response. In conclusion, both moderate and severe disturbances of sleep markedly affect glucose homeostasis and body weight control. PMID:20339560

  1. An Indian herbal formula (SKV) for controlling voluntary ethanol intake in rats with chronic alcoholism.

    PubMed

    Shanmugasundaram, E R; Shanmugasundaram, K R

    1986-08-01

    Chronic ethanol ingestion in rats showed metabolic and physiological changes similar to alterations reported in human alcoholics. There was a lowering of blood glucose concentration, urea and plasma proteins and elevated concentrations of serum gamma-glutamyl transpeptidase. Administration of SKV, an Ayurvedic formula produced by fermentation of cane sugar with raisins and 12 herbal ingredients brought down voluntary ethanol ingestion in the rats and increased food intake. ECG and EEG studies in alcoholic rats showed cardiac depression, augmentation of frequency and amplitude of the alpha, delta and theta waves and weakness in the beta waves. These changes were reversed during SKV-induced voluntary alcohol restriction. The involvement in the ECG and EEG wave patterns was associated with improvement in blood glucose, plasma protein levels and reduction in gamma glutamyl transpeptidase activities. SKV appeared to have no adverse reaction with ethanol (it contains 1-2% ethanol) and appears to be a promising way to combat alcoholism. PMID:3796018

  2. Effects of intrathecal kynurenate on arterial pressure during chronic osmotic stress in conscious rats

    PubMed Central

    Veitenheimer, Britta

    2013-01-01

    Increased plasma osmolality elevates mean arterial pressure (MAP) through activation of the sympathetic nervous system, but the neurotransmitters released in the spinal cord to regulate MAP during osmotic stress remain unresolved. Glutamatergic neurons of the rostral ventrolateral medulla project to sympathetic preganglionic neurons in the spinal cord and are likely activated during conditions of osmotic stress; however, this has not been examined in conscious rats. This study investigated whether increased MAP during chronic osmotic stress depends on activation of spinal glutamate receptors. Rats were chronically instrumented with an indwelling intrathecal (i.t.) catheter for antagonist delivery to the spinal cord and a radiotelemetry transmitter for continuous monitoring of MAP and heart rate. Osmotic stress induced by 48 h of water deprivation (WD) increased MAP by ∼15 mmHg. Intrathecal kynurenic acid, a nonspecific antagonist of ionotropic glutamate receptors, decreased MAP significantly more after 48 h of WD compared with the water-replete state. Water-deprived rats also showed a greater fall in MAP in response to i.t. 2-amino-5-phosphonovalerate. Finally, i.t. kynurenic acid also decreased MAP more in an osmotically driven model of neurogenic hypertension, the DOCA-salt rat, compared with normotensive controls. Our results suggest that spinally released glutamate mediates increased MAP during 48-h WD and DOCA-salt hypertension. PMID:23161878

  3. Plasma corticosterone response in continuous versus discontinuous chronic heat exposure in rat.

    PubMed

    Cure, M

    1989-06-01

    Effects of chronic exposure (25 days) to continuous (CHE) or discontinuous (DHE) hot environment (34 degrees C) on growth rate, food intake and cortico-adrenal function were studied in adult male rats. Growth rate and food intake were 40 and 31% less respectively in CHE and 7 and 9% less respectively in DHE than in control (CE) animals. The adrenal response to heat (40 degrees C) was reduced by 54 and 82% in CHE and DHE rats respectively but the plasma corticosterone (B) response to exogenous ACTH and ether stress was not altered by chronic heat. The plasma B rhythm was altered only in CHE rats which exhibited a 40% decrease in amplitude and a delayed nocturnal recession of plasma B values. These results indicate that 1) CHE induced major alterations of behavior specially during the nocturnal period of the L-D cycle, 2) that the altered circadian B rhythm of CHE rats could be linked to changes in feeding behavior and to reduced metabolic activity, 3) and that CHE induced a poorer adaptation than DHE.

  4. Acute and sub-chronic toxicity of aqueous extracts of Chenopodium ambrosioides leaves in rats.

    PubMed

    da Silva, Marcel Gianni C; Amorim, Raimundo Neilson L; Câmara, Carlos C; Fontenele Neto, José Domingues; Soto-Blanco, Benito

    2014-09-01

    The present study aimed to evaluate the toxicity of aqueous extract of Chenopodium ambrosioides leaves. To measure acute toxicity, rats were administered 0, 0.3, 1.0, or 3.0 g/kg of aqueous extract from C. ambrosioides leaves by gavage. To analyze sub-chronic toxicity, rats were treated by oral gavage for 15 consecutive days with 0, 0.3, or 1.0 g/kg of extract of C. ambrosioides leaves. No animals from either trial exhibited any signs of toxicity. In the acute study, the highest dose of the extract led to an increase in the serum activities of alanine transaminase (ALT) and aspartate transaminase (AST) and a decrease in the serum levels of urea. In the sub-chronic test, rats treated with 1.0 g/kg for 15 days exhibited increased serum ALT activity and creatinine levels and mild cytoplasmic vacuolation of hepatocytes. The results indicate that aqueous extract from C. ambrosioides leaves produce slight hepatotoxic lesions in rats.

  5. Sub-chronic exposure to paraoxon neither induces nor exacerbates diabetes mellitus in Wistar rat.

    PubMed

    Nurulain, Syed M; Petroianu, Georg; Shafiullah, Mohamed; Kalász, Huba; Oz, Murat; Saeed, Tariq; Adem, Abdu; Adeghate, Ernest

    2013-10-01

    There is an increasing belief that organophosphorus compounds (OPCs) impair glucose homeostasis and cause hyperglycemia and diabetes mellitus. The present study was undertaken to investigate the putative diabetogenic effect of sub-lethal and sub-chronic exposure to paraoxon (POX), an extremely hazardous OPC used in pesticides. The effect of paraoxon on streptozotocin-induced diabetic rats was also examined. Each rat was injected with 100 nmol of POX 5 days per week for 6 weeks. Blood glucose levels and red blood cell acetylcholinesterase activity were measured weekly. Biochemical analysis and morphological studies were performed at the end of the experiment. The results revealed that POX neither induces nor exacerbates diabetes mellitus in experimental rats. Liver and kidney/body weight ratios revealed statistically insignificant differences when compared with controls. Biochemical analysis of urine samples showed a small but not significant increase in protein level in all groups. Urine bilirubin was significantly higher in the diabetes + POX group when compared with the control group. The number of blood cells in urine was significantly higher in the POX-treated group compared with the control group. Hyperglycemia was noted in the diabetes and diabetes + POX groups, but neither in the saline control nor in POX-treated normal rats. Electron microscopy of POX-treated pancreas did not show any morphological changes in beta cells. These results suggest that POX does not cause diabetes mellitus at sub-lethal sub-chronic exposure.

  6. Alteration of bile acid metabolism in the rat induced by chronic ethanol consumption

    PubMed Central

    Xie, Guoxiang; Zhong, Wei; Li, Houkai; Li, Qiong; Qiu, Yunping; Zheng, Xiaojiao; Chen, Huiyuan; Zhao, Xueqing; Zhang, Shucha; Zhou, Zhanxiang; Zeisel, Steven H.; Jia, Wei

    2013-01-01

    Our understanding of the bile acid metabolism is limited by the fact that previous analyses have primarily focused on a selected few circulating bile acids; the bile acid profiles of the liver and gastrointestinal tract pools are rarely investigated. Here, we determined how chronic ethanol consumption altered the bile acids in multiple body compartments (liver, gastrointestinal tract, and serum) of rats. Rats were fed a modified Lieber-DeCarli liquid diet with 38% of calories as ethanol (the amount equivalent of 4–5 drinks in humans). While conjugated bile acids predominated in the liver (98.3%), duodenum (97.8%), and ileum (89.7%), unconjugated bile acids comprised the largest proportion of measured bile acids in serum (81.2%), the cecum (97.7%), and the rectum (97.5%). In particular, taurine-conjugated bile acids were significantly decreased in the liver and gastrointestinal tract of ethanol-treated rats, while unconjugated and glycine-conjugated species increased. Ethanol consumption caused increased expression of genes involved in bile acid biosynthesis, efflux transport, and reduced expression of genes regulating bile acid influx transport in the liver. These results provide an improved understanding of the systemic modulations of bile acid metabolism in mammals through the gut-liver axis.—Xie, G., Zhong, W., Li, H., Li, Q., Qiu, Y., Zheng, X., Chen, H., Zhao, X., Zhang, S., Zhou, Z., Zeisel, S. H., Jia, W. Alteration of bile acid metabolism in the rat induced by chronic ethanol consumption. PMID:23709616

  7. Toxicological assessment of combined lead and cadmium: acute and sub-chronic toxicity study in rats.

    PubMed

    Yuan, Guiping; Dai, Shujun; Yin, Zhongqiong; Lu, Hongke; Jia, Renyong; Xu, Jiao; Song, Xu; Li, Li; Shu, Yang; Zhao, Xinghong

    2014-03-01

    The exposure to chemical mixtures is a common and important determinant of toxicity and receives concern for their introduction by inhalation and ingestion. However, few in vivo mixture studies have been conducted to understand the health effects of chemical mixtures compared with single chemicals. In this study, the acute and 90day sub-chronic toxicity tests of combined Pb and Cd were conducted. In the acute toxicity test, the LD50 value of Pb(NO3)2 and CdCl2 mixture by the oral route was 2696.54mg/kg by Bliss method. The sub-chronic treatment revealed that the low-dose combination of Pb and Cd exposures can significantly change the physiological and biochemical parameters of the blood of Sprague-Dawley (SD) rats with dose-response relationship and causes microcytic hypochromic anemia and the damages of liver and kidney of the SD rats to various degrees. Histopathological exams showed that the target organs of Pb and Cd were testicle, liver, and kidneys. These observations suggest that Pb and Cd are practically additive-toxic for the SD rats in oral acute toxicity studies. The lowest observed adverse-effect level in rats may be lower than a dose of 29.96mg/(kgbwday) when administered orally for 90 consecutive days.

  8. Beneficial effects of polydatin on learning and memory in rats with chronic ethanol exposure.

    PubMed

    Zhang, Yan; Li, Shuang; Wang, Weifeng; Xu, Chunyang; Liang, Shuainan; Liu, Meng; Hao, Wei; Zhang, Ruiling

    2015-01-01

    The purpose of this paper is to examine the effects of polydatin on cognitive function in rats self-administered with chronic ethanol levels. The levels of cyclin-dependent kinase 5 (Cdk5) were also determined. In the in vivo study, adult male Sprague-Dawley rats were used to establish an ethanol-administered rat model. Cognitive function was measured using the Morris water maze and the level of Cdk5 expression was measured to evaluate the effect of polydatin treatment. Cdk5 kinase activity and cell survival rate in primary hippocampal neuron cultures treated with ethanol or ethanol and polydatin were measured in the in vitro study. Polydatin reversed the performance impairments in chronic ethanol treated rats in Morris water maze test, and decreased unregulated Cdk5 expression. Moreover, polydatin increased cell survival rate, and decreased Cdk5 activity in the ethanol-treated primary culture of hippocampal neurons. The study results suggest that polydatin exhibits neuroprotective potential for ethanol induced neurotoxicity, both in vivo and in vitro, which is most likely related to its ability to target Cdk5 in neurons.

  9. Beneficial effects of polydatin on learning and memory in rats with chronic ethanol exposure

    PubMed Central

    Zhang, Yan; Li, Shuang; Wang, Weifeng; Xu, Chunyang; Liang, Shuainan; Liu, Meng; Hao, Wei; Zhang, Ruiling

    2015-01-01

    The purpose of this paper is to examine the effects of polydatin on cognitive function in rats self-administered with chronic ethanol levels. The levels of cyclin-dependent kinase 5 (Cdk5) were also determined. In the in vivo study, adult male Sprague-Dawley rats were used to establish an ethanol-administered rat model. Cognitive function was measured using the Morris water maze and the level of Cdk5 expression was measured to evaluate the effect of polydatin treatment. Cdk5 kinase activity and cell survival rate in primary hippocampal neuron cultures treated with ethanol or ethanol and polydatin were measured in the in vitro study. Polydatin reversed the performance impairments in chronic ethanol treated rats in Morris water maze test, and decreased unregulated Cdk5 expression. Moreover, polydatin increased cell survival rate, and decreased Cdk5 activity in the ethanol-treated primary culture of hippocampal neurons. The study results suggest that polydatin exhibits neuroprotective potential for ethanol induced neurotoxicity, both in vivo and in vitro, which is most likely related to its ability to target Cdk5 in neurons. PMID:26617831

  10. Potential antiinflammatory effects of acupuncture in a chronic stress model of depression in rats.

    PubMed

    Lu, Jun; Shao, Run-Hui; Hu, Li; Tu, Ya; Guo, Jian-You

    2016-04-01

    Accumulating evidence indicates that inflammation may contribute to the pathophysiology of depression. Acupuncture in traditional Chinese medicine has been considered an effective treatment for depression. However, whether the mechanisms that underlie the antidepressant effect of acupuncture are related to its antiinflammatory properties remains unclear. In the present study, rats were exposed to chronic unpredictable mild stress (CUMS) for 28 days to induce depressive-like behavior. Body weight, sucrose preference, and locomotor activity in the open field were measured. After the behavioral tests, reverse transcription polymerase chain reaction was used to determine the mRNA expression of proinflammatory cytokines (interleukin-1β [IL-1β], interleukin-6 [IL-6], and tumor necrosis factor-α [TNF-α]), and enzyme-linked immunosorbent assay was used to detect cytokine concentrations. CUMS rats exhibited decrease in body weight, sucrose preference, and locomotor activity in the open field test. Chronic acupuncture and fluoxetine treatment reversed CUMS-induced depressive-like behavior. Compared with control rats, the mRNA and protein expression of IL-1β, IL-6, and TNF-α in the hippocampus and prefrontal cortex and cytokine concentrations in serum significantly increased in CUMS rats. Acupuncture and fluoxetine treatment significantly decreased the levels of proinflammatory cytokines in the hippocampus, prefrontal cortex, and serum. These results suggest that acupuncture has antidepressant-like effects, and its mechanism of action appears to involve the inhibition of proinflammatory cytokines. PMID:26921452

  11. Neurological and cellular regulation of visceral hypersensitivity induced by chronic stress and colonic inflammation in rats.

    PubMed

    Chen, J; Winston, J H; Sarna, S K

    2013-09-17

    The role of inflammation in inducing visceral hypersensitivity (VHS) in ulcerative colitis patients remains unknown. We tested the hypothesis that acute ulcerative colitis-like inflammation does not induce VHS. However, it sets up molecular conditions such that chronic stress following inflammation exaggerates single-unit afferent discharges to colorectal distension. We used dextran sodium sulfate (DSS) to induce ulcerative colitis-like inflammation and a 9-day heterotypic chronic stress protocol in rats. DSS upregulated Nav1.8 mRNA in colon-responsive dorsal root ganglion (DRG) neurons, TRPV1 in colonic muscularis externae (ME) and BDNF in spinal cord without affecting the spike frequency in spinal afferents or VMR to CRD. By contrast, chronic stress did not induce inflammation but it downregulated Kv1.1 and Kv1.4 mRNA in DRG neurons, and upregulated TRPA1 and nerve growth factor in ME, which mediated the increase of spike frequency and VMR to CRD. Chronic stress following inflammation exacerbated spike frequency in spinal afferent neurons. TRPA1 antagonist suppressed the sensitization of afferent neurons. DSS-inflammation did not affect the composition or excitation thresholds of low-threshold and high-threshold fibers. Chronic stress following inflammation increased the percent composition of high-threshold fibers and lowered the excitation threshold of both types of fibers. We conclude that not all types of inflammation induce VHS, whereas chronic stress induces VHS in the absence of inflammation. PMID:23806714

  12. Expression and interaction of TNF-α and VEGF in chronic stress-induced depressive rats

    PubMed Central

    LI, BAOHUA; WANG, BIN; CHEN, MIN; LI, GONGYING; FANG, MAOSHENG; ZHAI, JINGUO

    2015-01-01

    The incidence of depression increases annually but the pathogenesis is not yet fully understood. The aim of the present study was to explore the expression and interaction of tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF) in chronic stress-induced depressive rats. A total of 20 adult healthy Sprague Dawley rats (180–220 g) were randomly divided into the control and experimental depression groups. The depression model was established with a chronic stress method, and the success of model construction was assessed through weigh measurements and the sugar consumption and open-field tests. The expression of TNF-α and VEGF was detected using the reverse transcription quantitative polymerase chain reaction (RT-qPCR), western blotting and immunohistochemistry. Compared with the control group, the weight of the rats in the experimental group was found to be reduced (P<0.05). The open-field test showed significant differences in the horizontal and vertical motion of the rats between the two groups, and the rats in the experimental group exhibited a significantly reduced ability to adapt to a new environment (P<0.05). Furthermore, the sensitivity of the rats in the experimental group to reward stimulation was decreased. The relative mRNA expression levels of TNF-α and VEGF in the hippocampus of the experimental group were lower than those in the control group, and western blot analysis revealed that the protein expression of VEGF and TNF-α was reduced in the experimental group. Neurons of the experimental group exhibited reduced immunohistochemical staining compared with neurons from the normal hippocampus in the control group. In conclusion, the present study investigated the association between the occurrence of depression and TNF-α and VEGF at the mRNA and protein levels using RT-qPCR, western blotting, immunohistochemistry and animal behavior experiments. The results provide a fundamental basis for follow-up clinical research. PMID

  13. Effects of chronic exercise conditioning on thermal responses to lipopolysaccharide and turpentine abscess in female rats.

    PubMed

    Rowsey, Pamela Johnson; Metzger, Bonnie L; Carlson, John; Gordon, Christopher J

    2006-02-01

    Chronic exercise conditioning has been shown to alter basal thermoregulatory processes as well as the response to inflammatory agents. Two such agents, lipopolysaccharide (LPS) and turpentine (TPT) are inducers of fever in rats. LPS, given intraperitoneally (i.p.), involves a systemic inflammatory response whereas TPT given intramuscularly (i.m.) elicits a localized inflammation. We assessed if chronic exercise training in the rat would alter the thermoregulatory response to LPS and TPT. Core temperature (T (c)) and motor activity were monitored by radiotelemetry. Female Sprague Dawley rats were divided into two groups (trained and sedentary) and housed at an ambient temperature of 22 degrees C. Animals voluntarily trained on running wheels for 8 weeks. In the first study, trained and sedentary female rats were injected i.p. with LPS (50 microg/kg) or an equal volume of 0.9% normal saline. In another study, trained and sedentary female rats were injected i.m. with TPT (10 microl)/rat or an equal volume of 0.9% normal saline. The time course of the LPS fever was very short compared to TPT. TPT injected animals displayed a smaller but more prolonged fever compared to LPS; however, training accentuated the febrile response to LPS (DeltaT (c)=0.6 degrees C in sedentary and 1.2 degrees C in trained). Training had a slight suppression on TPT-induced fever during the daytime but had no effect on motor activity or nighttime T (c). In contrast, exercise training led to a marked increase in the pyrogenic effects of LPS. We conclude that the effect of exercise training and source of infection (i.e., systemic versus localized in muscle) on fever is directly linked to type of pyrogenic agent. PMID:16254718

  14. Chronic difluoromethylornithine treatment impairs spatial learning and memory in rats.

    PubMed

    Gupta, Neeraj; Zhang, Hu; Liu, Ping

    2012-01-01

    Recent evidence suggests that polyamines putrescine, spermidine and spermine are essential in maintaining normal cellular function. The present study investigated the effects of chronic treatment of difluoromethylornithine (DFMO, 3% in drinking water), a potent inhibitor of putrescine synthesis, for 54 consecutive days on animals'behavior and neurochemical levels in the CA1, CA2/3 and dentate gyrus sub-regions of the hippocampus and the prefrontal cortex. The DFMO group showed performance impairments in the place navigation and the probe test conducted 24 h after the training in the reference memory version of the water maze task, but not in the elevated plus maze, open field, object recognition, cued navigation and the working memory version of the water maze task when compared to the control group (drinking water only). DFMO treatment resulted in approximately 80-90% and 20% of reductions in the putrescine and spermidine levels, respectively, in the four brain regions examined, and a small reduction in agmatine level in the CA2/3, with no effects on spermine, glutamate and γ-aminobutyrate. The DFMO group showed decreased body weight relative to the control one. However, there were no significant differences between groups in the normalized brain, kidney and liver weights. The present study demonstrates that chronic treatment of DFMO depletes putrescine and decreases spermidine levels in the brain, inhibits growth, and impairs spatial learning and memory in the reference memory version of the water maze specifically. These findings merit further investigation to fully understand the functional role of endogenous polyamines in learning and memory.

  15. The effects of chronic photoperiod shifting on the physiology of female Long-Evans rats.

    PubMed

    Deibel, Scott H; Hong, Nancy S; Himmler, Stephanie M; McDonald, Robert J

    2014-04-01

    As the prevalence of shift work is increasing, it is important to elucidate the impact that shift work has on health. Because of the alternating work schedules present in rotating shift work and working at night, shift workers are in a chronic state of circadian disruption. Animal models of circadian disruption are useful because they offer more experimental control than the largely correlational human shift work studies. The effects of chronic circadian disruption on food preference, glucose tolerance, corticosterone secretion, and performance in a stress-inducing task were investigated in female Long-Evans rats. A 64-day photoperiod shifting paradigm was used to induce circadian disruption. Surprisingly, neither the photoperiod shifted animals, nor the control animals demonstrated a preference for either an unhealthy or healthy diet. Nor was there a difference between the groups in weight gained during photoperiod shifting. However, the photoperiod shifted rats gained significantly more weight than control animals, without eating more food during discriminative fear conditioning to context (DFCTC). Surprisingly, chronic photoperiod shifting appeared to facilitate retention in the DFCTC task. The photoperiod shifted animals also had increased serum glucose values during fasting and after a glucose challenge test. The photoperiod shifted animals only had elevated corticosterone during the final two phases of photoperiod shifting. This study demonstrates that chronic photoperiod shifting elicits weight gain when exposed to a stressful event and impairs glucose tolerance in the same individual. PMID:24631903

  16. The effects of chronic photoperiod shifting on the physiology of female Long-Evans rats.

    PubMed

    Deibel, Scott H; Hong, Nancy S; Himmler, Stephanie M; McDonald, Robert J

    2014-04-01

    As the prevalence of shift work is increasing, it is important to elucidate the impact that shift work has on health. Because of the alternating work schedules present in rotating shift work and working at night, shift workers are in a chronic state of circadian disruption. Animal models of circadian disruption are useful because they offer more experimental control than the largely correlational human shift work studies. The effects of chronic circadian disruption on food preference, glucose tolerance, corticosterone secretion, and performance in a stress-inducing task were investigated in female Long-Evans rats. A 64-day photoperiod shifting paradigm was used to induce circadian disruption. Surprisingly, neither the photoperiod shifted animals, nor the control animals demonstrated a preference for either an unhealthy or healthy diet. Nor was there a difference between the groups in weight gained during photoperiod shifting. However, the photoperiod shifted rats gained significantly more weight than control animals, without eating more food during discriminative fear conditioning to context (DFCTC). Surprisingly, chronic photoperiod shifting appeared to facilitate retention in the DFCTC task. The photoperiod shifted animals also had increased serum glucose values during fasting and after a glucose challenge test. The photoperiod shifted animals only had elevated corticosterone during the final two phases of photoperiod shifting. This study demonstrates that chronic photoperiod shifting elicits weight gain when exposed to a stressful event and impairs glucose tolerance in the same individual.

  17. Acute and chronic effect of ethanol on hepatic albumin synthesis in rat liver in vitro

    SciTech Connect

    Ohtake, H.; Kato, S.; Murawaki, Y.; Kishimoto, Y.; Wakushima, T.; Hirayama, C.

    1986-08-01

    To study the effects of ethanol and its metabolite on albumin metabolism, we examined the hepatic albumin synthesis and secretion in male Wistar rats in vitro, following acute and chronic ethanol administration. After acute ethanol administration, proalbumin synthesis in rat liver in vitro, declined to 47% of the control level at 4 hrs, the lowest level, and increased thereafter to slightly higher than the control level at 16 hrs. On the other hand, chronic ethanol administration for 4 weeks, increased proalbumin synthesis to 1.5 times that of the control level. In the acute ethanol group, a significant negative correlation was observed between proalbumin radioactivity and the concentration of hepatic ethanol and acetaldehyde. The variation between proalbumin radioactivity and hepatic ethanol concentration was wider than the variation between proalbumin and hepatic acetaldehyde. In the chronic ethanol group, ethanol was not detected in the liver. No significant differences from the proalbumin/albumin ratio were seen at any time point after acute or chronic ethanol administration. These findings suggest that the effects of ethanol on hepatic albumin synthesis differ with the method of ethanol administration, and acetaldehyde and/or ethanol is involved in the reduction in albumin synthesis, however, proalbumin-albumin conversion is not disturbed.

  18. Increase in synaptic hippocampal zinc concentration following chronic but not acute zinc treatment in rats.

    PubMed

    Szewczyk, Bernadeta; Sowa, Magdalena; Czupryn, Artur; Wierońska, Joanna M; Brański, Piotr; Sadlik, Krystyna; Opoka, Włodzimierz; Piekoszewski, Wojciech; Smiałowska, Maria; Skangiel-Kramska, Jolanta; Pilc, Andrzej; Nowak, Gabriel

    2006-05-23

    Electroconvulsive seizures (ECS), one of the most effective treatments of depression, induce mossy fiber sprouting (when assayed by means of synaptic zinc method), and this indicates an increase in the synaptic zinc level in the hippocampus following such therapy. The aim of the present study was to investigate the influence of acute and chronic zinc hydroaspartate administration on the synaptic and total zinc level in the rat hippocampus. We used two methods of zinc determination: (1) zinc-selenium method, which images the pool of synaptic zinc, and (2) flame atomic absorption spectrometry, which assays the total concentration of zinc. Our results indicate that chronic (14 x 65 mg/kg), but not acute, zinc hydroaspartate administration intraperitoneally (i.p.) increases the pool of synaptic zinc in the majority of rat hippocampal layers (by 72-190%), except for the stratum moleculare and stratum radiatum CA, and perforant path DG. On the other hand, no changes were found in total hippocampal zinc level, measured by flame atomic absorption spectrometry. These data suggest that chronic zinc treatment increases the pool of synaptic zinc in the hippocampus, and this effect is similar to that observed following chronic ECS treatment. The measurement of zinc concentration in the whole hippocampus by the flame atomic absorption spectrometry method is not sensitive enough to detect such subtle alteration. PMID:16674928

  19. Respiratory Network Enhances the Sympathoinhibitory Component of Baroreflex of Rats Submitted to Chronic Intermittent Hypoxia.

    PubMed

    Moraes, Davi J A; Bonagamba, Leni G H; da Silva, Melina P; Mecawi, André S; Antunes-Rodrigues, José; Machado, Benedito H

    2016-10-01

    Chronic intermittent hypoxia (CIH) produces respiratory-related sympathetic overactivity and hypertension in rats. In this study, we tested the hypothesis that the enhanced central respiratory modulation of sympathetic activity after CIH also decreases the sympathoinhibitory component of baroreflex of rats, which may contribute to the development of hypertension. Wistar rats were exposed to CIH or normoxia (control group) for 10 days. Phrenic nerve, thoracic sympathetic nerve, and neurons in the rostral ventrolateral medulla and caudal ventrolateral medulla were recorded in in situ preparations of rats. Baroreflex regulation of thoracic sympathetic nerve, rostral ventrolateral medulla, and caudal ventrolateral medulla neurons activities were evaluated in different phases of respiration in response to either aortic depressor nerve stimulation or pressure stimuli. CIH rats presented higher respiratory-related thoracic sympathetic nerve and rostral ventrolateral medulla presympathetic neurons activities at the end of expiration in relation to control rats, which are indexes of respiratory-related sympathetic overactivity. Baroreflex-evoked thoracic sympathetic nerve inhibition during expiration, but not during inspiration, was enhanced in CIH when compared with control rats. In addition, CIH selectively enhanced the expiratory-related baroreceptor inputs, probably through caudal ventrolateral medulla neurons, to the respiratory-modulated bulbospinal rostral ventrolateral medulla presympathetic neurons. These findings support the concept that the onset of hypertension, mediated by sympathetic overactivity, after 10 days of CIH is not secondary to a reduction in sympathoinhibitory component of baroreflex. Instead, it was observed an increase in the gain of sympathoinhibitory component in in situ preparations of rats, suggesting that changes in the respiratory-related sympathetic network after CIH also play a key role in preventing greater increase in arterial pressure

  20. Effect of chronic renal insufficiency on hepatic and renal udp-glucuronyltransferases in rats.

    PubMed

    Yu, Chuanhui; Ritter, Joseph K; Krieg, Richard J; Rege, Bhaskar; Karnes, Thomas H; Sarkar, Mohamadi A

    2006-04-01

    Significant evidence exists regarding altered CYP450 enzymes in chronic renal insufficiency (CRI), although none exists for the phase II enzymes. The objective of this study was to investigate the effect of CRI on hepatic and renal UDP-glucuronyltransferase (UGT) enzymes. Three groups of rats were included: CRI induced by the 5/6th nephrectomy model, control, and control pair-fed (CPF) rats. UGT activities were determined in liver and kidney microsomes by the 3- and 17-glucuronidation of beta-estradiol (E2-3G and E2-17G), glucuronidation of 4-methylumbelliferone (4-MUG), and 3-glucuronidation of morphine (M3G). UGT isoforms responsible for these catalytic activities were screened using recombinant rat UGT1A1, UGT1A2, UGT1A3, UGT1A7, UGT2B2, UGT2B3, and UGT2B8. UGT protein levels were examined by Western blot analysis using polyclonal antibodies. There was no significant difference between CRI and CPF rats in hepatic and/or renal E2-3G (UGT1A1), E2-17G (UGT2B3), 4-MUG (UGT1A6), and M3G (UGT2B1) formation. Formation of E2-17G and 4-MUG in the liver and E2-3G and 4-MUG in the kidney was significantly reduced (p < 0.05) in CPF and CRI rats compared with control rats. The down-regulated glucuronidation activities were accompanied by corresponding reductions in protein content of specific UGT isoforms. These results suggest that CRI does not seem to influence the protein levels or catalytic activity of most of the major hepatic or renal UGT enzymes. The observed down-regulation of hepatic and renal UGTs in CRI and CPF rats could be caused by restricted food intake in these groups of rats.

  1. Chronic ethanol treatment changes the number of beta-receptors in rat brain microvessels

    SciTech Connect

    Lucchi, L.; Cazzaniga, A.; Picotti, G.B.; Covelli, V.; Magnoni, M.S.; Borriero, L.; Spano, P.F.; Trabucchi, M.

    1984-01-01

    The effect of chronic ethanol consumption on the binding (125I)-iodohydroxybenzylpindolol to beta-adrenergic receptors in rat brain microvessels has been studied. The results show that chronic ethanol treatment increases the number of beta-receptors present in brain microvessels without changing the binding affinity of the binding site for the beta-adrenoceptor ligand. This effect is apparently not associated with changes in peripheral adrenergic tone, since no differences in platelet epinephrine or norepinephrine concentrations were found between ethanol-treated and control animals. An increase in beta-receptor density in brain microvessels might contribute to the alterations of cerebral blood flow and oxygen consumption reported during chronic ethanol intoxication.

  2. Effect of chronic neonatal morphine and naloxone on sensorimotor and social development of young rats.

    PubMed

    Najam, N; Panksepp, J

    1989-07-01

    Chronic morphine treatment of newborn Long-Evans rat pups between 3-26 days of age (thrice daily starting with 0.5 mg/kg, increased daily by 0.5 mg/kg to 10 mg/kg) led to lags of 1 to 3 days in physical development (body weights and eye opening times) and motor coordination (catalepsy test, grasping, swimming). Chronic naloxone treatment (5 mg/kg administered thrice daily from day 3-26), in contrast, led to modest gains in development on a number of measures (body weights, vaginal opening). Morphine animals also lagged behind controls and naloxone-tested animals in social behaviors, such as homing and play. Chronic naloxone did not block or retard social development; in fact naloxone-treated animals exhibited more rapid acquisition of homing behavior than controls.

  3. Chronic antidepressant treatments resulted in altered expression of genes involved in inflammation in the rat hypothalamus.

    PubMed

    Alboni, Silvia; Benatti, Cristina; Montanari, Claudia; Tascedda, Fabio; Brunello, Nicoletta

    2013-12-01

    To gain insight into the possible immune targets of antidepressant, we evaluated the expression of several inflammatory mediators in the hypothalamus of rats chronically (28 days) treated with the serotonin selective reuptake inhibitor fluoxetine (5mg/kg, i.p.) or the tricyclic compound imipramine (15 mg/kg, i.p.). We focused our attention on the hypothalamus as it plays a key role in determining many of the somatic symptoms experienced by depressed patients. This brain region, critical also for expression of motivated behaviours, participates in the control of the hypothalamic-pituitary-adrenal axis activity and in stress response as well as coordinates physiological functions such as sleep and food intake that have been found altered in a high percentage of depressed patients. Notably, hypothalamus is a key structure for brain cytokine expression and function as it integrates signals from the neuro, immune, endocrine systems. By means of quantitative Real Time PCR experiments we demonstrated that a chronic treatment with either fluoxetine or imipramine resulted in a reduction of IL-6 and IFN-γ mRNAs and increased IL-4 mRNA expression in the rat hypothalamus. Moreover, we demonstrated that hypothalamic expression of members of IL-18 system was differentially affected by chronic antidepressant treatments. Chronically administered fluoxetine decreased IL-8 and CX3CL1 hypothalamic expression, while a chronic treatment with imipramine decreased p11 mRNA. Our data suggest that a shift in the balance of the inflammation toward an anti-inflammatory state in the hypothalamus may represent a common mechanism of action of both the chronic treatments with fluoxetine and imipramine.

  4. Chronic Alcohol Ingestion in Rats Alters Lung Metabolism, Promotes Lipid Accumulation, and Impairs Alveolar Macrophage Functions

    PubMed Central

    Romero, Freddy; Shah, Dilip; Duong, Michelle; Stafstrom, William; Hoek, Jan B.; Kallen, Caleb B.; Lang, Charles H.

    2014-01-01

    Chronic alcoholism impairs pulmonary immune homeostasis and predisposes to inflammatory lung diseases, including infectious pneumonia and acute respiratory distress syndrome. Although alcoholism has been shown to alter hepatic metabolism, leading to lipid accumulation, hepatitis, and, eventually, cirrhosis, the effects of alcohol on pulmonary metabolism remain largely unknown. Because both the lung and the liver actively engage in lipid synthesis, we hypothesized that chronic alcoholism would impair pulmonary metabolic homeostasis in ways similar to its effects in the liver. We reasoned that perturbations in lipid metabolism might contribute to the impaired pulmonary immunity observed in people who chronically consume alcohol. We studied the metabolic consequences of chronic alcohol consumption in rat lungs in vivo and in alveolar epithelial type II cells and alveolar macrophages (AMs) in vitro. We found that chronic alcohol ingestion significantly alters lung metabolic homeostasis, inhibiting AMP-activated protein kinase, increasing lipid synthesis, and suppressing the expression of genes essential to metabolizing fatty acids (FAs). Furthermore, we show that these metabolic alterations promoted a lung phenotype that is reminiscent of alcoholic fatty liver and is characterized by marked accumulation of triglycerides and free FAs within distal airspaces, AMs, and, to a lesser extent, alveolar epithelial type II cells. We provide evidence that the metabolic alterations in alcohol-exposed rats are mechanistically linked to immune impairments in the alcoholic lung: the elevations in FAs alter AM phenotypes and suppress both phagocytic functions and agonist-induced inflammatory responses. In summary, our work demonstrates that chronic alcohol ingestion impairs lung metabolic homeostasis and promotes pulmonary immune dysfunction. These findings suggest that therapies aimed at reversing alcohol-related metabolic alterations might be effective for preventing and

  5. Chronic exercise decreases sensitivity to mu opioids in female rats: correlation with exercise output.

    PubMed

    Smith, Mark A; Lyle, Megan A

    2006-09-01

    Aerobic exercise stimulates the release of endogenous opioid peptides and increases nociceptive (i.e., pain) threshold in a naloxone-reversible manner. During chronic exercise, sensitivity to the antinociceptive effects of morphine and other mu opioids decreases, leading some investigators to propose that exercise may lead to the development of cross-tolerance to exogenously administered opioid agonists. The purpose of the present study was to examine the effects of chronic exercise on sensitivity to mu opioids, and to determine if changes in opioid sensitivity during chronic exercise are correlated with exercise output. Eight female rats were obtained at weaning and housed in standard laboratory cages that did not permit any exercise beyond normal cage ambulation. Following 6 weeks under these conditions, opioids possessing a range of relative efficacies at the mu receptor (morphine, levorphanol, buprenorphine, butorphanol) were examined in a warm-water, tail-withdrawal procedure. Under sedentary conditions, all opioids produced dose-dependent increases in tail-withdrawal latencies, and high levels of antinociception were observed for all drugs. Following these tests, rats were reassigned to exercise conditions and transferred to cages equipped with running wheels. Under these conditions, rats ran an average of 7154 rev/day (7869 m/day), with a range across rats from 4501 to 10,164 rev/day (4951-11,180 m/day). Sensitivity to all four opioids decreased significantly during the exercise period, resulting in 2- to 5-fold decreases in the potency of morphine, levorphanol and buprenorphine, and decreases in the effectiveness of buprenorphine and butorphanol. When rats were returned to sedentary conditions, sensitivity to all four opioids increased significantly and returned to that observed prior to the exercise period. For all drugs, there was a positive correlation between exercise output and changes in opioid sensitivity between sedentary and exercise conditions

  6. Effect of chronic hypokalemia on H(+)-K(+)-ATPase expression in rat colon.

    PubMed

    Codina, J; Pressley, T A; DuBose, T D

    1997-01-01

    Although the kidney plays the major role in the regulation of systemic K+ homeostasis, the colon also participates substantively in K+ balance. The colon is capable of both K+ absorption and secretion, the magnitude of which can be modulated in response to dietary K+ intake. The H(+)-K(+)-adenosinetriphosphatase (H(+)-K(+)-ATPase) has been proposed as a possible mediator of K+ absorption in distal colon, but inhibitor profiles obtained in recent studies suggest that two, and perhaps more, distinct H(+)-K(+)-ATPase activities may be present in mammalian distal colon. We have developed highly specific probes for the catalytic alpha-subunits of colonic and gastric H(+)-K(+)-ATPase, alpha 1-Na(+)-K(+)-ATPase, and beta-actin, which were used in Northern analysis of total RNA from whole distal colon and stomach obtained from one of three experimental groups of rats: 1) controls, 2) chronic dietary K+ depletion, and 3) chronic metabolic acidosis. The probe for the colonic but not the gastric H(+)-K(+)-ATPase alpha-isoform hybridized to distal colon total RNA in all groups. A significant increase in colonic H(+)-K(+)-ATPase mRNA abundance was observed in response to chronic dietary K+ depletion but not to chronic metabolic acidosis. The alpha 1-isoform of Na(+)-K(+)-ATPase, which is also expressed in distal colon, did not respond consistently to either chronic dietary K+ depletion or chronic metabolic acidosis. The gastric probe did not hybridize to total RNA from distal colon but, as expected, hybridized to total stomach RNA. However, the abundance of gastric H(+)-K(+)-ATPase or Na(+)-K(+)-ATPase in stomach was not altered consistently by either chronic dietary K+ depletion or metabolic acidosis. Under the conditions of this study, it appears that the mRNA encoding the colonic alpha-isoform is upregulated by chronic dietary K+ restriction, a condition shown previously to increase K+ absorption in the distal colon.

  7. Antiarthritic effects of Ajuga bracteosa Wall ex Benth. in acute and chronic models of arthritis in albino rats

    PubMed Central

    Kaithwas, Gaurav; Gautam, Raju; Jachak, Sanjay M; Saklani, Arvind

    2012-01-01

    Objective To evaluate the antiarthritic activity of Ajuga bracteosa using albino rats. Methods The antiarthritic activity of 70% ethanolic extract of Ajuga bracteosa (EEAB) was evaluated against turpentine oil- and formaldehyde- induced acute non immunological and complete freund's adjuvant (CFA)-induced chronic immunological arthritis in albino rats. Results EEAB showed a significant (P<0.05) and dose dependent inhibitory effect against acute and chronic models of arthritis. EEAB exhibited better antiarthritic activity than the standard aspirin. Conclusions EEAB exhibits a significant and promising antiarthritic activity against acute and chronic arthritis and supports the traditional use of Ajuga bracteosa for rheumatism and other inflammatory diseases. PMID:23569895

  8. The effects of chronic alcohol consumption and exercise on the skeleton of adult male rats

    NASA Technical Reports Server (NTRS)

    Reed, Adam H.; McCarty, Heidi L.; Evans, Glenda L.; Turner, Russell T.; Westerlind, Kim C.

    2002-01-01

    BACKGROUND: Lifestyle factors are known to affect skeletal development and integrity. Specifically, running has been reported to increase risk of fatigue fractures, whereas chronic alcohol consumption has been shown to reduce bone formation and bone mass. The combined effect of exercise and alcohol on the skeleton has yet to be explored, although alcohol consumption is common among certain physically active populations (e.g., military recruits, college athletes). It was hypothesized that chronic alcohol consumption would accentuate the inherent risk associated with endurance running exercise. METHODS: Six-month-old male Sprague Dawley rats were assigned to one of five groups: baseline, exercise-alcohol diet, exercise-normal diet, sham-alcohol diet, and sham-normal diet. Alcohol-fed rats (35% caloric intake) received a liquid diet ad libitum. Normal animals were pair-fed the identical diet with a maltose dextrin caloric substitute. Exercise was conducted on a motorized treadmill 5 days/wk for 16 weeks. Sham rats were placed on a stationary treadmill for matching time periods. Fluorochrome labels were administered 3 days before baseline and at 10 and 2 days before animals were killed. Heart, soleus, and rectus femoris muscles were wet weighed to assess the effects of training. Tibiae were collected for static and dynamic histomorphometric measurements on cancellous and cortical bone. RESULTS: Muscle weights were larger in the exercised rats versus the sham rats. Alcohol had no significant effect on skeletal muscle weight but did result in larger heart weights in both alcohol-treated groups. Cancellous and periosteal bone formation rates were significantly decreased in the alcohol-fed rats versus rats on the normal diet and were associated with a significant reduction in trabecular thickness in the tibial metaphysis. Cortical and cross-sectional areas were also significantly lower in the alcohol-fed groups compared with the non-alcohol-fed groups. Exercise had no

  9. Long-term effects of chronic oral Ritalin administration on cognitive and neural development in adolescent wistar kyoto rats.

    PubMed

    Pardey, Margery C; Kumar, Natasha N; Goodchild, Ann K; Clemens, Kelly J; Homewood, Judi; Cornish, Jennifer L

    2012-09-12

    The diagnosis of Attention Deficit Hyperactivity Disorder (ADHD) often results in chronic treatment with psychostimulants such as methylphenidate (MPH, Ritalin®). With increases in misdiagnosis of ADHD, children may be inappropriately exposed to chronic psychostimulant treatment during development. The aim of this study was to assess the effect of chronic Ritalin treatment on cognitive and neural development in misdiagnosed "normal" (Wistar Kyoto, WKY) rats and in Spontaneously Hypertensive Rats (SHR), a model of ADHD. Adolescent male animals were treated for four weeks with oral Ritalin® (2 × 2 mg/kg/day) or distilled water (dH2O). The effect of chronic treatment on delayed reinforcement tasks (DRT) and tyrosine hydroxylase immunoreactivity (TH-ir) in the prefrontal cortex was assessed. Two weeks following chronic treatment, WKY rats previously exposed to MPH chose the delayed reinforcer significantly less than the dH2O treated controls in both the DRT and extinction task. MPH treatment did not significantly alter cognitive performance in the SHR. TH-ir in the infralimbic cortex was significantly altered by age and behavioural experience in WKY and SHR, however this effect was not evident in WKY rats treated with MPH. These results suggest that chronic treatment with MPH throughout adolescence in "normal" WKY rats increased impulsive choice and altered catecholamine development when compared to vehicle controls.

  10. Should dialysis modalities be designed to remove specific uremic toxins?

    PubMed

    Baurmeister, Ulrich; Vienken, Joerg; Ward, Richard A

    2009-01-01

    The definition of optimal dialysis therapy remains elusive. Randomized clinical trials have neither supported using urea as a surrogate marker for uremic toxicity nor provided clear cut evidence in favor of larger solutes. Thus, where to focus resources in the development of new membranes, and therapies remains unclear. Three basic questions remain unanswered: (i) what solute(s) should be used as a marker for optimal dialysis; (ii) should dialytic therapies be designed to remove a specific solute; and (iii) how can current therapies be modified to provide better control of uremic toxicity? Identification of a single, well-defined uremic toxin appears to be unlikely as new analytical tools reveal an increasingly complex uremic milieu. As a result, it is probable that membranes and therapies should be designed for the nonspecific removal of a wide variety of solutes retained in uremia. Removal of the widest range of solutes can best be achieved using existing therapies that incorporate convection in conjunction with longer treatment times and more frequent treatments. Membranes capable of removing solutes over an expanded effective molecular size range can already be fabricated; however, their use will require novel approaches to conserve proteins, such as albumin.

  11. Adult hemolytic-uremic syndrome and bone marrow necrosis

    SciTech Connect

    Hicks, C.B.; Redmond, J. III

    1984-11-01

    A case is reported of adult hemolytic-uremic syndrome in which massive bone marrow necrosis developed, a previously undescribed complication. Technetium-99m minicolloid scanning and indium-111 bone marrow scans were used to demonstrate lack of bone marrow activity in the patient. 11 references, 2 figures.

  12. Even a Chronic Mild Hyperglycemia Affects Membrane Fluidity and Lipoperoxidation in Placental Mitochondria in Wistar Rats

    PubMed Central

    Figueroa-García, María del Consuelo; Espinosa-García, María Teresa; Martinez-Montes, Federico; Palomar-Morales, Martín; Mejía-Zepeda, Ricardo

    2015-01-01

    It is known the deleterious effects of diabetes on embryos, but the effects of diabetes on placenta and its mitochondria are still not well known. In this work we generated a mild hyperglycemia model in female wistar rats by intraperitoneal injection of streptozotocin in 48 hours-old rats. The sexual maturity onset of the female rats was delayed around 6–7 weeks and at 16 weeks-old they were mated, and sacrificed at day 19th of pregnancy. In placental total tissue and isolated mitochondria, the fatty acids composition was analyzed by gas chromatography, and lipoperoxidation was measured by thiobarbituric acid reactive substances. Membrane fluidity in mitochondria was measured with the excimer forming probe dipyrenylpropane and mitochondrial function was measured with a Clark-type electrode. The results show that even a chronic mild hyperglycemia increases lipoperoxidation and decreases mitochondrial function in placenta. Simultaneously, placental fatty acids metabolism in total tissue is modified but in a different way than in placental mitochondria. Whereas the chronic mild hyperglycemia induced a decrease in unsaturated to saturated fatty acids ratio (U/S) in placental total tissue, the ratio increased in placental mitochondria. The measurements of membrane fluidity showed that fluidity of placenta mitochondrial membranes increased with hyperglycemia, showing consistency with the fatty acids composition through the U/S index. The thermotropic characteristics of mitochondrial membranes were changed, showing lower transition temperature and activation energies. All of these data together demonstrate that even a chronic mild hyperglycemia during pregnancy of early reproductive Wistar rats, generates an increment of lipoperoxidation, an increase of placental mitochondrial membrane fluidity apparently derived from changes in fatty acids composition and consequently, mitochondrial malfunction. PMID:26630275

  13. Even a Chronic Mild Hyperglycemia Affects Membrane Fluidity and Lipoperoxidation in Placental Mitochondria in Wistar Rats.

    PubMed

    Figueroa-García, María del Consuelo; Espinosa-García, María Teresa; Martinez-Montes, Federico; Palomar-Morales, Martín; Mejía-Zepeda, Ricardo

    2015-01-01

    It is known the deleterious effects of diabetes on embryos, but the effects of diabetes on placenta and its mitochondria are still not well known. In this work we generated a mild hyperglycemia model in female wistar rats by intraperitoneal injection of streptozotocin in 48 hours-old rats. The sexual maturity onset of the female rats was delayed around 6-7 weeks and at 16 weeks-old they were mated, and sacrificed at day 19th of pregnancy. In placental total tissue and isolated mitochondria, the fatty acids composition was analyzed by gas chromatography, and lipoperoxidation was measured by thiobarbituric acid reactive substances. Membrane fluidity in mitochondria was measured with the excimer forming probe dipyrenylpropane and mitochondrial function was measured with a Clark-type electrode. The results show that even a chronic mild hyperglycemia increases lipoperoxidation and decreases mitochondrial function in placenta. Simultaneously, placental fatty acids metabolism in total tissue is modified but in a different way than in placental mitochondria. Whereas the chronic mild hyperglycemia induced a decrease in unsaturated to saturated fatty acids ratio (U/S) in placental total tissue, the ratio increased in placental mitochondria. The measurements of membrane fluidity showed that fluidity of placenta mitochondrial membranes increased with hyperglycemia, showing consistency with the fatty acids composition through the U/S index. The thermotropic characteristics of mitochondrial membranes were changed, showing lower transition temperature and activation energies. All of these data together demonstrate that even a chronic mild hyperglycemia during pregnancy of early reproductive Wistar rats, generates an increment of lipoperoxidation, an increase of placental mitochondrial membrane fluidity apparently derived from changes in fatty acids composition and consequently, mitochondrial malfunction. PMID:26630275

  14. The control of glomerular filtration rate and renal blood flow in chronically volume-expanded rats.

    PubMed Central

    Davis, J M; Häberle, D A; Kawata, T

    1988-01-01

    1. Chronic volume expansion by dietary salt loading practically abolishes tubuloglomerular feed-back (TGF) by means of a humoral inhibitor in tubular fluid. Elimination of the vasoconstrictor influence of feed-back does not, however, increase glomerular filtration rate (GFR) and renal blood flow (RBF), implying that chronic salt loading induces additional preglomerular vasoconstriction. This being so, the feed-back response which, although absent in free-flowing nephrons, can still be elicited by loop of Henle perfusion with Ringer solution, should be essentially normal, except that nephron GFR at any loop perfusion rate should be lower than in controls. Persistence of RBF, GFR and nephron GFR autoregulation would imply that autoregulation is achieved by a preglomerular resistance control system independent of feed-back. 2. These hypotheses were tested by clearance and micropuncture experiments in rats chronically fed a diet containing 40 g NaCl (kg food)-1. 3. RBF and GFR autoregulation indeed persisted, the former down to 90 mmHg compared with 105 mmHg in controls. In controls, nephron GFR measured distally was autoregulated down to 90 mmHg whereas that measured proximally was autoregulated only above 105 mmHg. In high-salt rats nephron GFR from both sites was autoregulated to 90 mmHg. 4. Loop of Henle perfusion with homologous tubular fluid in high-salt rats confirmed attenuation of feed-back. Loop perfusion with Ringer solution yielded a response comparable to that in controls (maximal reduction of nephron GFR to 57%, compared with 56% in controls). Absolute nephron GFR at any loop perfusion rate was lower in high-salt rats than in controls. 5. These observations confirm the initial hypotheses. Considering feed-back and autoregulation as independent, preglomerular resistance control mechanisms, together with elementary haemodynamic considerations, allows formulation of a renal haemodynamics model whose quantitative predictions regarding characteristics of RBF

  15. Effects of chronic ethanol consumption on rat upper gastrointestinal system: functional and histologic findings.

    PubMed

    Yazir, Yusufhan; Tugay, Melih; Utkan, Zafer; Utkan, Tijen

    2012-11-01

    The purpose of the present study was to determine the effect of chronic alcohol consumption on reactivity of esophageal tunica muscularis mucosae (TMM) and lower esophageal sphincter (LES) smooth muscle. Six male rats in alcohol-fed group received ethanol (7.2% v/v) in a modified liquid diet for 4 weeks. Two control groups were used; six rats in the standard diet-fed group received rat chow and water for 4 weeks. Six rats in sucrose-fed group were given sucrose and received a liquid diet. The smooth muscle reactivity of TMM and LES strips from ethanol-fed and control animals was evaluated in organ chambers. Also histologic study was undertaken to show effects of chronic alcohol consumption. Maximum contractile responses of TMM to KCl and carbachol were decreased in the ethanol-fed group compared to the control groups. Relaxant responses to serotonin were decreased in the ethanol-fed group compared to the control groups. In TMM, isoproterenol- and papaverine-induced relaxant responses were similar in the ethanol-fed and control groups. In LES smooth muscle, relaxant responses to papaverine or isoproterenol were similar in the control groups and the ethanol-fed group. There was no change in agonist potency among the groups. The relaxation response elicited by nicotine and sodium nitroprusside (SNP) or contractile response elicited by carbachol and 80 mM KCl was decreased with maximum responses and pD(2) values, in the ethanol-fed group compared to that of the control groups in LES. Decreased nNOS immunoreactivity in myenteric plexus was found in alcohol-exposed group compared to control groups. Our findings suggest that chronic alcohol consumption impairs relaxant and contractile responses of both TMM and LES smooth muscle and it may contribute to gastroesophageal reflux commonly seen after alcohol binges.

  16. The effects of chronic ethanol treatment on endothelium-dependent responses in rat thoracic aorta.

    PubMed

    Williams, S P; Adams, R D; Mustafa, S J

    1990-01-01

    The purpose of this study was to investigate the effects of chronic ethanol consumption on blood pressure and vascular responses, specifically, the possible alterations in endothelium-dependent relaxation which are associated with ethanol-induced hypertension in the rat model. Male rats received ethanol in drinking water for 13 weeks. Systolic pressure was recorded weekly. Following treatment, segments of thoracic aorta with and without intact endothelium were used to generate relaxation-response curves to the endothelium-dependent agents, acetylcholine, ATP and bradykinin, as well as the endothelium-independent agents, adenosine and sodium nitroprusside. Mean systolic pressures at the end of the treatment period were: 127.8 +/- 1.2 and 151.1 +/- 1.3 mmHg for controls and ethanol-treated rats, respectively. Ethanol treatment did not affect the relaxation produced by either acetylcholine, ATP or sodium nitroprusside in aorta with or without endothelium. In contrast, ring segments with intact endothelium from ethanol-treated rats exhibited augmented relaxation in response to both adenosine and bradykinin compared to controls. Removal of the endothelium abolished the relaxation produced by bradykinin in both groups. Although removal of the endothelium had no effect on the relaxation produced by adenosine in the control group, it attenuated the adenosine-induced relaxation in the ethanol-treated group back to control levels. These data suggest that chronic ingestion of ethanol causes elevated blood pressure and augments the endothelium-dependent relaxation to bradykinin. These findings also suggest that chronic ethanol treatment can cause the appearance of an endothelium-dependent component in the relaxation produced by adenosine.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Studies on the reproductive effects of chronic treatment with agomelatine in the rat.

    PubMed

    Canpolat, Sinan; Ulker, Nazife; Yardimci, Ahmet; Bulmus, Ozgur; Ozdemir, Gokcen; Sahin, Zafer; Ercan, Zubeyde; Serhatlioglu, Ihsan; Kacar, Emine; Ozcan, Mete; Turk, Gaffari; Ozkan, Yusuf; Atmaca, Murad; Yilmaz, Bayram; Kelestimur, Haluk

    2016-01-01

    Agomelatine is an antidepressant with a novel mechanism of action. It is a melatonergic agonist for MT1 and MT2 receptors and a serotonin (5-HT2C) receptor antagonist. Agomelatine has been suggested not to have adverse effects on sexual functions. However, the effects of chronic agomelatine administration on reproductive functions have not been sufficiently studied in animal models. We mainly aimed to explore the effects of agomelatine on reproductive functions in the male and female rats. For the experimental studies, Sprague Dawley rats were used. The animals started to receive daily oral agomelatine (10mg/kg) on post-natal day 21. Agomelatine advanced vaginal opening in the female rats whereas it delayed puberty onset in the male rats. Agomelatine treatment significantly decreased intromission frequencies, which indicates a facilitator role of this antidepressant on male sexual behavior. In the forced swimming test (FST) used for assessing antidepressant efficacy, agomelatine induced a significant decrease in duration of immobility, and an increase in the swimming time, respectively, which confirms the antidepressant-like activity of agomelatine. The present findings suggest that agomelatine shows a strong antidepressant effect in the male rats without any adverse influences on sexual behavior, and its effects on pubertal maturation seem to show sex-dependent differences. PMID:26643170

  18. Toxic effect on the rat small intestine of chronic administration of asbestos in drinking water.

    PubMed

    Delahunty, T J; Hollander, D

    1987-12-01

    Sprague-Dawley rats were given a 0.5 g/l Chrysotile asbestos solution in their drinking water (approximately 7 mg/day ingested) for 1.5 years and compared to control rats of the same age. During this time there were no differences in weight or appearance of the asbestos-treated rats in comparison to controls maintained under the same conditions. However, when in vivo intestinal permeability studies were performed using a gavage/urinary collection technique, some significant changes were noted. The recovery of lactulose in the urine of asbestos-treated rats was 0.66 +/- 0.07%, significantly less than that of the controls (1.01 +/- 0.08, P less than 0.005). The recovery of mannitol was similarly decreased (2.2 +/- 0.28 vs. 3.0 +/- 0.17, P less than 0.02), but that of rhamnose was unchanged. Creatinine clearance studies indicated that there was no impairment of kidney function in the asbestos-treated group and polarized light microscopy did not reveal any asbestos fibers in sections of the small bowel. The results suggest that the chronic exposure of rats to asbestos fibers in the drinking water results in a decreased ability of the intestine to absorb some non-metabolizable sugars. PMID:3120357

  19. Repeated paroxetine treatment reverses anhedonia induced in rats by chronic mild stress or dexamethasone.

    PubMed

    Casarotto, P C; Andreatini, R

    2007-11-01

    The present study was designed to assess the effect of dexamethasone, a synthetic glucocorticoid receptor agonist, in the sucrose preference test in rats. Rats treated acutely with dexamethasone (5-10 mg/kg) showed a significant decrease in sucrose preference (anhedonia) in comparison to vehicle treated rats, although 1 mg/kg dexamethasone did not alter the sucrose preference. Daily paroxetine treatment (10 g/kg, i.p., 14 days) reversed the anhedonic effect of acute dexamethasone (5 mg/kg), while causing no increased sucrose preference in rats that received dexamethasone vehicle. The paroxetine vehicle treated rats showed anhedonia even 14 days after acute dexamethasone administration. Paroxetine (10 mk/kg, i.p. for 28 days) also reversed anhedonia induced by chronic mild stress (8 weeks). In conclusion, acute dexamethasone induced an enduring anhedonic state that was reversed by repeated paroxetine treatment. Thus, the present study adds new data to the evidence supporting an important role for glucocorticoid in depression.

  20. Impact of lead sub-chronic toxicity on recognition memory and motor activity of Wistar rat.

    PubMed

    Azzaoui, F Z; Ahami, A O T; Khadmaoui, A

    2009-01-15

    The aim of this research was to investigate the impact of lead nitrate administered in drinking water during 90 days (sub-chronic toxicity), on body weight gain, motor activity, brain lead accumulation and especially on recognition memory of Wistar rats. Two groups of young female Wistar rats were used. Treated rats received 20 mg L(-1) of lead nitrate diluted in drinking water, while control rats received drinking water only, for 3 months. An evolution of body weight, motor activity, object recognition memory and measure of brain lead levels has been evaluated. The body weight was taken weekly, whereas the memory abilities and the motor activity are measured once every fortnight alternatively, by submitting rats to the Open Field (OF) test and to the Novel Object Recognizing (NOR) memory test. The results have shown a non significant effect in gain of body weight. However, a high significance was shown for horizontal activity (p<0.01), long memory term (p<0.01), at the end of testing period and for brain lead levels (p<0.05) between studied groups.

  1. Chronic systemic administration of 5-HT produces weight loss in mature adult male rats.

    PubMed

    Edwards, S

    1995-09-01

    Adult male rats were allowed to free-feed until their body weights had stabilised. They were next trained onto a 4 h per day feeding regimen, until further stabilisation occurred. All rats then received saline injections for 5 days, to establish baseline body weights. One group was then injected with 5.0 mg/kg 5-HT daily for 30 days while the other group continued with saline. Progressive and significant weight loss occurred in the drug-treated animals. After 30 days, the 5-HT-treated rats had lost 7.0% of their baseline body weights, whereas the control group had gained 1.3%. At this point, the 5-HT treated rats were switched back to saline injections to investigate rebound effects. Although the group that had received 5-HT treatment showed evidence of rebound weight gain, mean weights at the end of the 10 day rebound period were still 4.5% lower than baseline values. These data clearly indicate that chronic systemic administration of 5-HT can produce considerable weight loss in rats.

  2. Effect of chronic intracerebroventricular angiotensin II infusion on vasopressin release in rats

    NASA Technical Reports Server (NTRS)

    Sterling, G. H.; Chee, O.; Riggs, R. V.; Keil, L. C.

    1980-01-01

    The effects of the chronic infusion of angiotensin II into the lateral cerebral ventricle on the release of arginine vasopressin in rats are investigated. Rats were subjected to a continuous infusion of angiotensin at a rate of 1 microgram/h for five days, during which they were offered water, isotonic saline or hypertonic saline ad libitum or 40 ml water/day, and fluid intake, changes in body weight, plasma sodium ion concentrations and plasma and pituitary arginine vasopressin levels were measured. Angiotensin II is found to increase the fluid intake of rats given isotonic saline and decrease plasma sodium ion levels with no changes in plasma or pituitary arginine vasopressin in those given water or isotonic saline. However, in rats given hypertonic saline, plasma sodium concentrations remained at control levels while plasma vasopressin increased, and in water-restricted rats the effects of angiotensin II were intermediate. Results thus demonstrate that angiotensin II-stimulated arginine vasopressin release is reduced under conditions in which plasma sodium ion concentration becomes dilute, compatible with a central role of angiotensin in the regulation of salt and water balance.

  3. Exercise training upregulates nitric oxide synthases in the kidney of rats with chronic heart failure.

    PubMed

    Ito, Daisuke; Ito, Osamu; Mori, Nobuyoshi; Cao, Pengyu; Suda, Chihiro; Muroya, Yoshikazu; Hao, Kiyotaka; Shimokawa, Hiroaki; Kohzuki, Masahiro

    2013-09-01

    There is an interaction between heart and kidney diseases, which is a condition termed cardiorenal syndrome. Exercise training has cardioprotective effects, involving upregulation of endothelial (e) nitric oxide synthase (NOS) in the cardiovascular system. However, the effects of exercise training on NOS in the kidney with heart disease are unknown. The aim of the present study was to investigate whether exercise training upregulates NOS in the kidney, left ventricle and aorta of rats with chronic heart failure (CHF). Male Sprague-Dawley rats underwent left coronary artery ligation (LCAL) to induce CHF and were randomly assigned to sedentary or treadmill exercise groups 4 weeks after LCAL. Three days after exercising for 4 weeks, urine samples were collected for 24 h and blood samples were collected following decapitation. Nitric oxide synthase activity and protein expression were examined. Significant interactions between CHF and exercise training were observed on parameters of cardiac and renal function. Exercise training improved cardiac function, decreased plasma B-type natriuretic peptide levels, decreased urinary albumin excretion and increased creatinine clearance in CHF rats. Nitric oxide synthase activity, eNOS expression and neuronal (n) NOS expression were significantly decreased in the left ventricle and kidney of CHF rats. Exercise training significantly increased NOS activity and eNOS and nNOS expression. Upregulation of NOS in the kidney and left ventricle may contribute, in part, to the renal and cardiac protective effects of exercise training in cardiorenal syndrome in CHF rats.

  4. Studies on the reproductive effects of chronic treatment with agomelatine in the rat.

    PubMed

    Canpolat, Sinan; Ulker, Nazife; Yardimci, Ahmet; Bulmus, Ozgur; Ozdemir, Gokcen; Sahin, Zafer; Ercan, Zubeyde; Serhatlioglu, Ihsan; Kacar, Emine; Ozcan, Mete; Turk, Gaffari; Ozkan, Yusuf; Atmaca, Murad; Yilmaz, Bayram; Kelestimur, Haluk

    2016-01-01

    Agomelatine is an antidepressant with a novel mechanism of action. It is a melatonergic agonist for MT1 and MT2 receptors and a serotonin (5-HT2C) receptor antagonist. Agomelatine has been suggested not to have adverse effects on sexual functions. However, the effects of chronic agomelatine administration on reproductive functions have not been sufficiently studied in animal models. We mainly aimed to explore the effects of agomelatine on reproductive functions in the male and female rats. For the experimental studies, Sprague Dawley rats were used. The animals started to receive daily oral agomelatine (10mg/kg) on post-natal day 21. Agomelatine advanced vaginal opening in the female rats whereas it delayed puberty onset in the male rats. Agomelatine treatment significantly decreased intromission frequencies, which indicates a facilitator role of this antidepressant on male sexual behavior. In the forced swimming test (FST) used for assessing antidepressant efficacy, agomelatine induced a significant decrease in duration of immobility, and an increase in the swimming time, respectively, which confirms the antidepressant-like activity of agomelatine. The present findings suggest that agomelatine shows a strong antidepressant effect in the male rats without any adverse influences on sexual behavior, and its effects on pubertal maturation seem to show sex-dependent differences.

  5. Chronic Psychosocial Stress Impairs Bone Homeostasis: A Study in the Social Isolation Reared Rat

    PubMed Central

    Schiavone, Stefania; Morgese, Maria G.; Mhillaj, Emanuela; Bove, Maria; De Giorgi, Angelo; Cantatore, Francesco P.; Camerino, Claudia; Tucci, Paolo; Maffulli, Nicola; Cuomo, Vincenzo; Trabace, Luigia

    2016-01-01

    Chronic psychosocial stress is a key player in the onset and aggravation of mental diseases, including psychosis. Although a strong association between this psychiatric condition and other medical co-morbidities has been recently demonstrated, few data on the link between psychosis and bone homeostasis are actually available. The aim of this study was to investigate whether chronic psychosocial stress induced by 4 or 7 weeks of social isolation in drug-naïve male Wistar rats could alter bone homeostasis in terms of bone thickness, mineral density and content, as well as markers of bone formation and resorption (sclerostin, cathepsin K, and CTX-I). We found that bone mineral density was increased in rats exposed to 7 weeks of social isolation, while no differences were detected in bone mineral content and area. Moreover, 7 weeks of social isolation lead to increase of femur thickness with respect to controls, suggesting the development of a hyperostosis condition. Isolated rats showed no changes in sclerostin levels, a marker of bone formation, compared to grouped animals. Conversely, bone resorption markers were significantly altered after 7 weeks of social isolation in terms of decrease in cathepsin K and increase of CTX-I. No alterations were found after 4 weeks of isolation rearing. Our observations suggest that chronic psychosocial stress might affect bone homeostasis, more likely independently from drug treatment. Thus, the social isolation model might help to identify possible new therapeutic targets to treat the burden of chronic psychosocial stress and to attempt alternative therapy choices. PMID:27375486

  6. Methylprednisolone Stiffens Aortas in Lipopolysaccharide-Induced Chronic Inflammation in Rats

    PubMed Central

    Ko, Ya-Hui; Tsai, Ming-Shian; Lee, Po-Huang; Liang, Jin-Tung; Chang, Kuo-Chu

    2013-01-01

    Introduction Glucocorticoids are commonly used as therapeutic agents in many acute and chronic inflammatory and auto-immune diseases. The current study investigated the effects of methylprednisolone (a synthetic glucocorticoid) on aortic distensibility and vascular resistance in lipopolysaccharide-induced chronic inflammation in male Wistar rats. Methods Chronic inflammation was induced by implanting a subcutaneous slow-release ALZET osmotic pump (1 mg kg−1 day−1 lipopolysaccharide) for either 2 or 4 weeks. Arterial wave transit time (τ) was derived to describe the elastic properties of aortas using the impulse response function of the filtered aortic input impedance spectra. Results Long-term lipopolysaccharide challenge enhanced the expression of advanced glycation end products (AGEs) in the aortas. Lipopolysaccharide also upregulated the inducible form of nitric oxide synthase to produce high levels of nitric oxide (NO), which resulted in vasodilation, as evidenced by the fall in total peripheral resistance (Rp). However, lipopolysaccharide challenge did not influence the elastic properties of aortas, as shown by the unaltered τ. The NO-mediated vascular relaxation may counterbalance the AGEs-induced arterial stiffening so that the aortic distensibility remained unaltered. Treating lipopolysaccharide-challenged rats with methylprednisolone prevented peripheral vasodilation because of its ability to increase Rp. However, methylprednisolone produced an increase in aorta stiffness, as manifested by the significant decline in τ. The diminished aortic distensibility by methylprednisolone paralleled a significant reduction in NO plasma levels, in the absence of any significant changes in AGEs content. Conclusion Methylprednisolone stiffens aortas and elastic arteries in lipopolysaccharide-induced chronic inflammation in rats, for NO activity may be dominant as a counteraction of AGEs. PMID:23874978

  7. Chronic Administration of Catechin Decreases Depression and Anxiety-Like Behaviors in a Rat Model Using Chronic Corticosterone Injections

    PubMed Central

    Lee, Bombi; Sur, Bongjun; Kwon, Sunoh; Yeom, Mijung; Shim, Insop; Lee, Hyejung; Hahm, Dae-Hyun

    2013-01-01

    Previous studies have demonstrated that repeated administration of the exogenous stress hormone corticosterone (CORT) induces dysregulation in the hypothalamic-pituitary-adrenal (HPA) axis and results in depression and anxiety. The current study sought to verify the impact of catechin (CTN) administration on chronic CORT-induced behavioral alterations using the forced swimming test (FST) and the elevated plus maze (EPM) test. Additionally, the effects of CTN on central noradrenergic systems were examined by observing changes in neuronal tyrosine hydroxylase (TH) immunoreactivity in rat brains. Male rats received 10, 20, or 40 mg/kg CTN (i.p.) 1 h prior to a daily injection of CORT for 21 consecutive days. The activation of the HPA axis in response to the repeated CORT injections was confirmed by measuring serum levels of CORT and the expression of corticotrophin-releasing factor (CRF) in the hypothalamus. Daily CTN administration significantly decreased immobility in the FST, increased open-arm exploration in the EPM test, and significantly blocked increases of TH expression in the locus coeruleus (LC). It also significantly enhanced the total number of line crossing in the open-field test (OFT), while individual differences in locomotor activities between experimental groups were not observed in the OFT. Taken together, these findings indicate that the administration of CTN prior to high-dose exogenous CORT significantly improves helpless behaviors, possibly by modulating the central noradrenergic system in rats. Therefore, CTN may be a useful agent for the treatment or alleviation of the complex symptoms associated with depression and anxiety disorders. PMID:24244817

  8. Chronic NOS inhibition accelerates NAFLD progression in an obese rat model

    PubMed Central

    Sheldon, Ryan D.; Padilla, Jaume; Jenkins, Nathan T.; Laughlin, M. Harold

    2015-01-01

    The progression in nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis is a serious health concern, but the underlying mechanisms remain unclear. We hypothesized that chronic inhibition of nitric oxide (NO) synthase (NOS) via Nω-nitro-l-arginine methyl ester (l-NAME) would intensify liver injury in a rat model of obesity, insulin resistance, and NAFLD. Obese Otsuka Long-Evans Tokushima fatty (OLETF) and lean Long-Evans Tokushima Otsuka (LETO) rats received control or l-NAME (65–70 mg·kg−1·day−1)-containing drinking water for 4 wk. l-NAME treatment significantly (P < 0.05) reduced serum NO metabolites and food intake in both groups. Remarkably, despite no increase in body weight, l-NAME treatment increased hepatic triacylglycerol content (+40%, P < 0.05) vs. control OLETF rats. This increase was associated with impaired (P < 0.05) hepatic mitochondrial state 3 respiration. Interestingly, the opposite effect was found in LETO rats, where l-NAME increased (P < 0.05) hepatic mitochondrial state 3 respiration. In addition, l-NAME induced a shift toward proinflammatory M1 macrophage polarity, as indicated by elevated hepatic CD11c (P < 0.05) and IL-1β (P = 0.07) mRNA in OLETF rats and reduced expression of the anti-inflammatory M2 markers CD163 and CD206 (P < 0.05) in LETO rats. Markers of total macrophage content (CD68 and F4/80) mRNA were unaffected by l-NAME in either group. In conclusion, systemic NOS inhibition in the obese OLETF rats reduced hepatic mitochondrial respiration, increased hepatic triacylglycerol accumulation, and increased hepatic inflammation. These findings suggest an important role for proper NO metabolism in the hepatic adaptation to obesity. PMID:25573175

  9. Chronic NOS inhibition accelerates NAFLD progression in an obese rat model.

    PubMed

    Sheldon, Ryan D; Padilla, Jaume; Jenkins, Nathan T; Laughlin, M Harold; Rector, R Scott

    2015-03-15

    The progression in nonalcoholic fatty liver disease (NAFLD) to nonalcoholic steatohepatitis is a serious health concern, but the underlying mechanisms remain unclear. We hypothesized that chronic inhibition of nitric oxide (NO) synthase (NOS) via N(ω)-nitro-L-arginine methyl ester (L-NAME) would intensify liver injury in a rat model of obesity, insulin resistance, and NAFLD. Obese Otsuka Long-Evans Tokushima fatty (OLETF) and lean Long-Evans Tokushima Otsuka (LETO) rats received control or L-NAME (65-70 mg·kg(-1)·day(-1))-containing drinking water for 4 wk. L-NAME treatment significantly (P < 0.05) reduced serum NO metabolites and food intake in both groups. Remarkably, despite no increase in body weight, L-NAME treatment increased hepatic triacylglycerol content (+40%, P < 0.05) vs. control OLETF rats. This increase was associated with impaired (P < 0.05) hepatic mitochondrial state 3 respiration. Interestingly, the opposite effect was found in LETO rats, where L-NAME increased (P < 0.05) hepatic mitochondrial state 3 respiration. In addition, L-NAME induced a shift toward proinflammatory M1 macrophage polarity, as indicated by elevated hepatic CD11c (P < 0.05) and IL-1β (P = 0.07) mRNA in OLETF rats and reduced expression of the anti-inflammatory M2 markers CD163 and CD206 (P < 0.05) in LETO rats. Markers of total macrophage content (CD68 and F4/80) mRNA were unaffected by L-NAME in either group. In conclusion, systemic NOS inhibition in the obese OLETF rats reduced hepatic mitochondrial respiration, increased hepatic triacylglycerol accumulation, and increased hepatic inflammation. These findings suggest an important role for proper NO metabolism in the hepatic adaptation to obesity. PMID:25573175

  10. Effects of chronic ethanol ingestion on pharmacokinetics of procainamide in rats.

    PubMed

    Gole, D J; Nagwekar, J B

    1991-03-01

    Blood level studies were carried out in rats to determine the effects of chronic ethanol ingestion on the distribution pharmacokinetic parameters and tissue steady-state partition coefficients of procainamide. The ethanol-treated rats received 4g/kg of ethanol daily for 28 days in Treatment A and 4 g/kg of ethanol for an initial 7 days, followed by 8 g/kg of ethanol for the subsequent 21 days in Treatment B; the control rats received isocaloric sucrose in the respective groups. As determined from two-compartment analysis of the blood level data, both ethanol treatments significantly decreased the distribution clearance (CLd; k12Vdc) and the apparent first-order rate constant for drug transfer from the central compartment to the tissue compartment (k12) of procainamide without affecting the total body clearance of drug (CL) or the apparent volumes of distribution of drug in the body at steady state (Vdss) and at pseudo-equilibrium (Vd beta). Additionally, the apparent volume of distribution of the drug in the central compartment (Vdc) was 57-62% greater due to both ethanol treatments. Furthermore, the steady-state partition coefficients of the drug were found to be significantly lower in heart and kidneys and greater in fat of the ethanol-treated rats (Treatment B) as compared with those in the control rats. Possible mechanisms are proposed to account for these various effects in light of the known effects of chronic ethanol ingestion on the chemical composition of cell membranes of tissues and organs.

  11. Chronic alcohol ingestion alters claudin expression in the alveolar epithelium of rats.

    PubMed

    Fernandez, Alberto L; Koval, Michael; Fan, Xian; Guidot, David M

    2007-08-01

    Previously we determined that chronic alcohol ingestion (6 weeks) in rats increases lung epithelial permeability in vivo approximately 5-6-fold and promotes flooding of the alveolar airspaces with proteinaceous fluid in response to stresses such as sepsis. In parallel, alveolar epithelial cells isolated from alcohol-fed rats fail to form tight monolayers in vitro, even when cultured for up to 8 days in the absence of alcohol. However, the molecular mechanisms underlying alcohol-induced permeability are unknown. Claudins are key components of tight junctions that restrict the paracellular movement of water, proteins, and solutes across cellular barriers including the alveolar epithelium. In this study, we examined the expression of multiple members of the claudin protein family in the lungs of alcohol-fed versus control-fed rats (Lieber-DeCarli liquid diet with either 36% of calories as alcohol or an isocaloric substitution with maltin-dextrin for 6 weeks). We determined that chronic alcohol ingestion affected the expression of multiple claudins; most striking were decreases in claudin-1 and claudin-7, and an increase in claudin-5, in the whole lung and in alveolar epithelial monolayers derived from alcohol-fed rats. In parallel, immunocytochemistry of alveolar epithelial monolayers from alcohol-fed rats revealed abnormal intracellular accumulation of claudin-7 protein and relatively decreased localization to cell membranes. Claudin-1 and claudin-7 are relatively specific to alveolar epithelial type I pneumocytes that form the vast majority of the alveolar epithelial barrier in vivo, and increases in claudin-5 have been associated with increased epithelial permeability in other systems. Therefore, these findings suggest that changes in claudin expression in the alveolar epithelium produce a "leakier" phenotype that renders the alcoholic lung susceptible to alveolar flooding during acute inflammatory stresses.

  12. Acid Reflux Directly Causes Sleep Disturbances in Rat with Chronic Esophagitis

    PubMed Central

    Nakahara, Kenichi; Fujiwara, Yasuhiro; Tsukahara, Takuya; Yamagami, Hirokazu; Tanigawa, Tetsuya; Shiba, Masatsugu; Tominaga, Kazunari; Watanabe, Toshio; Urade, Yoshihiro; Arakawa, Tetsuo

    2014-01-01

    Background & Aims Gastroesophageal reflux disease (GERD) is strongly associated with sleep disturbances. Proton pump inhibitor (PPI) therapy improves subjective but not objective sleep parameters in patients with GERD. This study aimed to investigate the association between GERD and sleep, and the effect of PPI on sleep by using a rat model of chronic acid reflux esophagitis. Methods Acid reflux esophagitis was induced by ligating the transitional region between the forestomach and the glandular portion and then wrapping the duodenum near the pylorus. Rats underwent surgery for implantation of electrodes for electroencephalogram and electromyogram recordings, and they were transferred to a soundproof recording chamber. Polygraphic recordings were scored by using 10-s epochs for wake, rapid eye movement sleep, and non-rapid eye movement (NREM) sleep. To examine the role of acid reflux, rats were subcutaneously administered a PPI, omeprazole, at a dose of 20 mg/kg once daily. Results Rats with reflux esophagitis presented with several erosions, ulcers, and mucosal thickening with basal hyperplasia and marked inflammatory infiltration. The reflux esophagitis group showed a 34.0% increase in wake (232.2±11.4 min and 173.3±7.4 min in the reflux esophagitis and control groups, respectively; p<0.01) accompanied by a reduction in NREM sleep during light period, an increase in sleep fragmentation, and more frequent stage transitions. The use of omeprazole significantly improved sleep disturbances caused by reflux esophagitis, and this effect was not observed when the PPI was withdrawn. Conclusions Acid reflux directly causes sleep disturbances in rats with chronic esophagitis. PMID:25215524

  13. Effects of moderate and chronic exercise on the nitrergic system and behavioral parameters in rats.

    PubMed

    Pietrelli, Adriana; López-Costa, Juan José; Goñi, Ricardo; López, Esther María; Brusco, Alicia; Basso, Nidia

    2011-05-10

    Several reports suggest that nitric oxide (NO) could play a critical role on synaptic plasticity related to physical activity improving learning and memory; thus, physical exercise would have important effects on cerebral health. In order to analyze the long-term effects of chronic moderate physical training on the morphology and activity of nitrergic neurons belonging to the cerebral cortex, hippocampus and striatum, and their relationship with behavioral parameters. Wistar rats were aerobically trained (AT) up to the age of 18months and compared to sedentary controls (SC). At the end of the training protocol behavioral parameters were analyzed in an eight-arms radial maze. Rats were sacrificed by perfusion fixation with 4% paraformaldehyde. Brains were dissected out and coronal sections containing the three mentioned areas were obtained. The neurons expressing nitric oxide synthase (NOS) were stained using the technique of NADPH-diaphorase (NADPH-d) and their morphological and densitometric parameters were quantified by image analysis. Afterwards, the isoforms of NOS were determined by immunofluorescence. Results revealed AT rats learned faster, performed less mistakes and were more successful than SC rats in the maze. The nitrergic neurons of the cerebral cortex were larger and they had an increased number of dendrites. The NADPH-d reactivity in the cortex and striatum was upregulated. Colocalization was significant for the neuronal nitric oxide synthase (nNOS), in both groups. In conclusion, moderate and chronic exercise had a positive effect on cognitive performance and anxiety related behavior. An upregulation of the nitrergic system was detected in AT rats and this fact could be involved in this beneficial action on the aged subjects.

  14. Effects of chronic estradiol or testosterone treatment upon sexual behavior in sexually sluggish male rats.

    PubMed

    Antonio-Cabrera, Edwards; Paredes, Raúl G

    2012-05-01

    Sexually sluggish (SS) male rats represent a small proportion of animals that take a long time to ejaculate, or sometimes they do not ejaculate, when tested on repeated occasions with sexually receptive females. The current study was done in order to evaluate whether chronic estradiol (E(2)) or testosterone (T) treatment could induce consistent ejaculatory behavior in these male rats. Those males that displayed sexual behavior but did not ejaculate in at least four of five tests were classified as SS and included in the present experiment. They were implanted subcutaneously with Silastic capsules that were empty or filled with E(2) or T. Starting one week after the implant, subjects were tested weekly with sexually receptive females for seven consecutive weeks. At the end of the experiment all subjects were weighed and sacrificed to weigh the accessory sex glands. The results showed that SS males implanted with an empty or T-filled capsule remained as such; they displayed mounts and intromissions but not a consistent pattern of ejaculation despite the twelve weeks of testing (5 screening tests and 7 with the corresponding implant). In contrast, the percentage of SS males implanted with an E(2) capsule that displayed the ejaculatory pattern was significantly reduced. Subjects treated with E(2) also displayed a higher number of mounts than the empty capsule group during several weeks of testing. At the end of the experiment the weights of the body, testicles, epididymis, seminal vesicles, and prostate of the SS male rats chronically treated with E(2) were lower than those of the empty or T capsule groups. In addition, male rats with a T implant showed lower testicular weight than the empty capsule group. These results suggest that the lack of ejaculation patter in SS male rats is not due to estrogenic or androgenic alteration.

  15. Altered neurochemical levels in the rat brain following chronic nicotine treatment.

    PubMed

    Falasca, Sara; Ranc, Vaclav; Petruzziello, Filomena; Khani, Abbas; Kretz, Robert; Zhang, Xiaozhe; Rainer, Gregor

    2014-09-01

    Converging evidence shows that neurochemical systems are crucial mediators of nicotine dependence. Our present study evaluates the effect of 3-month chronic nicotine treatment on the levels of multiple quaternary ammonium compounds as well as glutamate and gamma aminobutyric acid in the rat prefrontal cortex, dorsal striatum and hypothalamus. We observed a marked decrease of acetylcholine levels in the dorsal striatum (22.88%, p<0.01), reflecting the impact of chronic nicotine in local interneuron circuits. We found decreases of carnitine in the dorsal striatum and prefrontal cortex (19.44%, p<0.01; 13.58%, p<0.01, respectively), but robust enhancements of carnitine in the hypothalamus (26.59%, p<0.01), which may reflect the alterations in food and water intake during chronic nicotine treatment. Finally, we identified an increase of prefrontal cortex glutamate levels (8.05%, p<0.05), supporting previous studies suggesting enhanced prefrontal activity during chronic drug use. Our study shows that quaternary ammonium compounds are regulated in a highly brain region specific manner during chronic nicotine treatment, and provides novel insights into neurochemical regulation during nicotine use.

  16. Increased extracellular levels of glutamate in the hippocampus of chronically epileptic rats.

    PubMed

    Soukupova, M; Binaschi, A; Falcicchia, C; Palma, E; Roncon, P; Zucchini, S; Simonato, M

    2015-08-20

    An increase in the release of excitatory amino acids has consistently been observed in the hippocampus during seizures, both in humans and animals. However, very little or nothing is known about the extracellular levels of glutamate and aspartate during epileptogenesis and in the interictal chronic period of established epilepsy. The aim of this study was to systematically evaluate the relationship between seizure activity and changes in hippocampal glutamate and aspartate extracellular levels under basal and high K(+)-evoked conditions, at various time-points in the natural history of experimental temporal lobe epilepsy, using in vivo microdialysis. Hippocampal extracellular glutamate and aspartate levels were evaluated: 24h after pilocarpine-induced status epilepticus (SE); during the latency period preceding spontaneous seizures; immediately after the first spontaneous seizure; in the chronic (epileptic) period. We found that (i) basal (spontaneous) glutamate outflow is increased in the interictal phases of the chronic period, whereas basal aspartate outflow remains stable for the entire course of the disease; (ii) high K(+) perfusion increased glutamate and aspartate outflow in both control and pilocarpine-treated animals, and the overflow of glutamate was clearly increased in the chronic group. Our data suggest that the glutamatergic signaling is preserved and even potentiated in the hippocampus of epileptic rats, and thus may favor the occurrence of spontaneous recurrent seizures. Together with an impairment of GABA signaling (Soukupova et al., 2014), these data suggest that a shift toward excitation occurs in the excitation/inhibition balance in the chronic epileptic state. PMID:26073699

  17. An electron microscopical study of chronic ulcers of the colon in rats.

    PubMed Central

    Reeve, D. R.

    1977-01-01

    Chronic colonic ulcers in the rat were produced by the administration of a hydrogen peroxide enema. Lesions of up to 10 months' duration were obtained by this method and a selection was examined ultrastructurally. It was hoped that the study would reveal causes for the chronicity of the lesions. From previous work it appeared that there was no failure of epithelial migration from the edge of the wound. The majority of cells at the ulcer margins demonstrated features of regeneration similar to those seen in other tissues, and that there were no specific changes concomitant with chronic ulceration. The majority of epithelial cells at the ulcer edge showed features of differentiation which indicated that there was no obvious fault in this process so essential to the basic requirements of tissue repair. It is possible that chronicity is produced by a failure of the epithelio-mesenchymal interaction mechanisms which, potentiated by an ischaemia resulting from submucosal vascular damage, results in the consequential death of migrating epithelial cells. This hypothesis is supported by the appearance of a squamous metaplasia in the healing lesions, a process which is commonly attributed to a chronic inflammatory response which may be induced by a relative vascular insufficiency. Images Fig. 11 Fig. 12 Fig. 13 Fig. 14 Fig. 15 Fig. 16 Fig. 17 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 1 Fig. 2 Fig. 3 Fig. 8 Fig. 9 Fig. 10 PMID:836769

  18. Subacute stress and chronic stress interact to decrease intestinal barrier function in rats.

    PubMed

    Lauffer, Adriana; Vanuytsel, Tim; Vanormelingen, Christophe; Vanheel, Hanne; Salim Rasoel, Shadea; Tóth, Joran; Tack, Jan; Fornari, Fernando; Farré, Ricard

    2016-01-01

    Psychological stress increases intestinal permeability, potentially leading to low-grade inflammation and symptoms in functional gastrointestinal disorders. We assessed the effect of subacute, chronic and combined stress on intestinal barrier function and mast cell density. Male Wistar rats were allocated to four experimental groups (n = 8/group): 1/sham; 2/subacute stress (isolation and limited movement for 24 h); 3/chronic crowding stress for 14 days and 4/combined subacute and chronic stress. Jejunum and colon were collected to measure: transepithelial electrical resistance (TEER; a measure of epithelial barrier function); gene expression of tight junction molecules; mast cell density. Plasma corticosterone concentration was increased in all three stress conditions versus sham, with highest concentrations in the combined stress condition. TEER in the jejunum was decreased in all stress conditions, but was significantly lower in the combined stress condition than in the other groups. TEER in the jejunum correlated negatively with corticosterone concentration. Increased expression of claudin 1, 5 and 8, occludin and zonula occludens 1 mRNAs was detected after subacute stress in the jejunum. In contrast, colonic TEER was decreased only after combined stress, and the expression of tight junction molecules was unaltered. Increased mast cell density was observed in the chronic and combined stress condition in the colon only. In conclusion, our data show that chronic stress sensitizes the gastrointestinal tract to the effects of subacute stress on intestinal barrier function; different underlying cellular and molecular alterations are indicated in the small intestine versus the colon.

  19. Chronic ethanol tolerance as a result of free-choice drinking in alcohol-preferring rats of the WHP line.

    PubMed

    Dyr, Wanda; Taracha, Ewa

    2012-01-01

    The development of tolerance to alcohol with chronic consumption is an important criterion for an animal model of alcoholism and may be an important component of the genetic predisposition to alcoholism. The aim of this study was to determine whether the selectively bred Warsaw High Preferring (WHP) line of alcohol-preferring rats would develop behavioral and metabolic tolerance during the free-choice drinking of ethanol. Chronic tolerance to ethanol-induced sedation was tested. The loss of righting reflex (LRR) paradigm was used to record sleep duration in WHP rats. Ethanol (EtOH)-naive WHP rats received a single intraperitoneal (i.p.) injection of 5.0 g ethanol/kg body weight (b.w.), and sleep duration was measured. Subsequently, rats had access to a 10% ethanol solution under a free-choice condition with water and food for 12 weeks. After 12 weeks of the free-choice intake of ethanol, the rats received another single i.p. injection of 5.0 g ethanol/kg b.w., and sleep duration was reassessed. The blood alcohol content (BAC) for each rat was determined after an i.p. injection of 5 g/kg of ethanol in naive rats and again after chronic alcohol drinking at the time of recovery of the righting reflex (RR). The results showed that the mean ethanol intake was 9.14 g/kg/24 h, and both sleep duration and BAC were decreased after chronic ethanol intake. In conclusion, WHP rats exposed to alcohol by free-choice drinking across 12 weeks exhibited increased alcohol elimination rates. Studies have demonstrated that WHP rats after chronic free-choice drinking (12 weeks) of alcohol develop metabolic tolerance. Behavioral tolerance to ethanol was demonstrated by reduced sleep duration, but this decrease in sleep duration was not significant.

  20. Fluid reabsorption in Henle's loop and urinary excretion of sodium and water in normal rats and rats with chronic hypertension

    PubMed Central

    Stumpe, Klaus O.; Lowitz, Hans D.; Ochwadt, Bruno

    1970-01-01

    The function of the short loops of Henle was investigated by micropuncture technique in normal rats, in rats with spontaneous hypertension, and in the untouched kidney of rats with experimental renal hypertension. All animals received a standard infusion of 1.2 ml of isotonic saline per hr. With increasing arterial blood pressure (range from 90 to 220 mm Hg), a continuous decrease in transit time of Lissamine green through Henle's loop from 32 to 10 sec was observed. Fractional water reabsorption along the loop declined progressively from 26 to 10%, and fractional sodium reabsorption decreased from 40 to 36% of the filtered load. The fluid volume in Henle's loop calculated from transit time and mean flow rate also decreased with increasing blood pressure. There was no change in superficial single nephron filtration rate but there was a slight increase in total glomerular filtration rate (GFR). Sodium and water reabsorption in the proximal tubule remained unchanged. Urine flow rate, sodium excretion, osmolar clearance, and negative free water clearance increased with increasing blood pressure. The osmolal urine to plasma (U/P) ratio declined but did not fall below a value of 1.5. It is concluded that the increase in sodium and water excretion with chronic elevation of arterial blood pressure is caused by a decrease of sodium and water reabsorption along the loop of Henle, presumably as a consequence of increased medullary blood pressure. PMID:5422022

  1. Corticosterone mediates the synaptic and behavioral effects of chronic stress at rat hippocampal temporoammonic synapses.

    PubMed

    Kvarta, Mark D; Bradbrook, Keighly E; Dantrassy, Hannah M; Bailey, Aileen M; Thompson, Scott M

    2015-09-01

    Chronic stress is thought to impart risk for depression via alterations in brain structure and function, but contributions of specific mediators in generating these changes remain unclear. We test the hypothesis that stress-induced increases in corticosterone (CORT), the primary rodent glucocorticoid, are the key mediator of stress-induced depressive-like behavioral changes and synaptic dysfunction in the rat hippocampus. In rats, we correlated changes in cognitive and affective behavioral tasks (spatial memory consolidation, anhedonia, and neohypophagia) with impaired excitatory strength at temporoammonic-CA1 (TA-CA1) synapses, an archetypical stress-sensitive excitatory synapse. We tested whether elevated CORT was sufficient and necessary to generate a depressive-like behavioral phenotype and decreased excitatory signaling observed at TA-CA1 after chronic unpredictable stress (CUS). Chronic CORT administration induced an anhedonia-like behavioral state and neohypophagic behavior. Like CUS, chronic, but not acute, CORT generated an impaired synaptic phenotype characterized by reduced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-preferring glutamate receptor-mediated excitation at TA-CA1 synapses, decreased AMPA-type glutamate receptor subunit 1 protein expression, and altered serotonin-1B receptor-mediated potentiation. Repeatedly blunting stress-induced increases of CORT during CUS with the CORT synthesis inhibitor metyrapone (MET) prevented these stress-induced neurobehavioral changes. MET also prevented the CUS-induced impairment of spatial memory consolidation. We conclude that corticosterone is sufficient and necessary to mediate glutamatergic dysfunction underlying stress-induced synaptic and behavioral phenotypes. Our results indicate that chronic excessive glucocorticoids cause specific synaptic deficits in the hippocampus, a major center for cognitive and emotional processing, that accompany stress-induced behavioral dysfunction

  2. Corticosterone mediates the synaptic and behavioral effects of chronic stress at rat hippocampal temporoammonic synapses

    PubMed Central

    Kvarta, Mark D.; Bradbrook, Keighly E.; Dantrassy, Hannah M.; Bailey, Aileen M.

    2015-01-01

    Chronic stress is thought to impart risk for depression via alterations in brain structure and function, but contributions of specific mediators in generating these changes remain unclear. We test the hypothesis that stress-induced increases in corticosterone (CORT), the primary rodent glucocorticoid, are the key mediator of stress-induced depressive-like behavioral changes and synaptic dysfunction in the rat hippocampus. In rats, we correlated changes in cognitive and affective behavioral tasks (spatial memory consolidation, anhedonia, and neohypophagia) with impaired excitatory strength at temporoammonic-CA1 (TA-CA1) synapses, an archetypical stress-sensitive excitatory synapse. We tested whether elevated CORT was sufficient and necessary to generate a depressive-like behavioral phenotype and decreased excitatory signaling observed at TA-CA1 after chronic unpredictable stress (CUS). Chronic CORT administration induced an anhedonia-like behavioral state and neohypophagic behavior. Like CUS, chronic, but not acute, CORT generated an impaired synaptic phenotype characterized by reduced α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-preferring glutamate receptor-mediated excitation at TA-CA1 synapses, decreased AMPA-type glutamate receptor subunit 1 protein expression, and altered serotonin-1B receptor-mediated potentiation. Repeatedly blunting stress-induced increases of CORT during CUS with the CORT synthesis inhibitor metyrapone (MET) prevented these stress-induced neurobehavioral changes. MET also prevented the CUS-induced impairment of spatial memory consolidation. We conclude that corticosterone is sufficient and necessary to mediate glutamatergic dysfunction underlying stress-induced synaptic and behavioral phenotypes. Our results indicate that chronic excessive glucocorticoids cause specific synaptic deficits in the hippocampus, a major center for cognitive and emotional processing, that accompany stress-induced behavioral dysfunction

  3. Dexmedetomidine controls twitch-convulsive syndrome in the course of uremic encephalopathy.

    PubMed

    Nomoto, Koichi; Scurlock, Corey; Bronster, David

    2011-12-01

    An 85 year old man with a history of chronic renal insufficiency was admitted to the cardiothoracic intensive care unit after aortic valve replacement. His postoperative course was marked by acute oliguric renal failure for high blood urea nitrogen (BUN) and acute hyperactive delirium. At this time he also developed tremors with muscle twitching; he received no other form of sedatives. A neurology consult made the diagnosis of twitch-convulsive syndrome associated with uremic encephalopathy. While the patient was receiving the dexmedetomidine infusion, the signs of the twitch-convulsive syndrome, particularly the twitching and tremors, disappeared. Within 30 minutes of the end of the dexmedetomidine infusion, symptoms of the twitch-convulsive syndrome returned, manifesting as acute tremulousness. After several dialysis treatments, his BUN decreased and the dexmedetomidine was weaned, without return of the symptoms of twitch-convulsive syndrome. PMID:22137518

  4. Changes in proinflammatory cytokines and white matter in chronically stressed rats

    PubMed Central

    Yang, Ping; Gao, Zhenyong; Zhang, Handi; Fang, Zeman; Wu, Cairu; Xu, Haiyun; Huang, Qing-Jun

    2015-01-01

    Although the pathogenesis of depression, an incapacitating psychiatric ailment, remains largely unknown, previous human and animal studies have suggested that both proinflammatory cytokines and altered oligodendrocytes play important roles in the condition. This study examined these two factors in the brains of rats following unpredictable chronic mild stress for 4 weeks, with the hypothesis that chronic stress may affect oligodendrocytes and elevate proinflammatory cytokines in the brain. After suffering unpredictable stressors for 4 weeks, the rats showed depression-like behaviors, including decreased locomotion in the open field, increased immobility time in the forced swim test, and decreased sucrose consumption and less sucrose preference when compared with controls. Immunohistochemical staining of brain sections showed higher immunoreactivity of proinflammatory cytokines in certain brain regions of stressed rats compared with controls; lower immunoreactivity of myelin basic protein and fewer mature oligodendrocytes were seen in the prefrontal cortex, but no demyelination was detected. These results are interpreted and discussed in the context of recent findings from human and animal studies. PMID:25834438

  5. Environmental enrichment and cafeteria diet attenuate the response to chronic variable stress in rats.

    PubMed

    Zeeni, N; Bassil, M; Fromentin, G; Chaumontet, C; Darcel, N; Tome, D; Daher, C F

    2015-02-01

    Exposure to an enriched environment (EE) or the intake of a highly palatable diet may reduce the response to chronic stress in rodents. To further explore the relationships between EE, dietary intake and stress, male Sprague-Dawley rats were fed one of two diets for 5 weeks: high carbohydrate (HC) or "cafeteria" (CAF) (Standard HC plus a choice of highly palatable cafeteria foods: chocolate, biscuits, and peanut butter). In addition, they were either housed in empty cages or cages with EE. After the first two weeks, half of the animals from each group were stressed daily using a chronic variable stress (CVS) paradigm, while the other half were kept undisturbed. Rats were sacrificed at the end of the 5-week period. The effects of stress, enrichment and dietary intake on animal adiposity, serum lipids, and stress hormones were analyzed. Results showed an increase in intra-abdominal fat associated with the CAF diet and an increase in body weight gain associated with both the CAF diet and EE. Furthermore, the increase in ACTH associated with CVS was attenuated in the presence of EE and the CAF diet independently while the stress-induced increase in corticosterone was reduced by the combination of EE and CAF feeding. The present study provides evidence that the availability of a positive environment combined to a highly palatable diet increases resilience to the effects of CVS in rats. These results highlight the important place of palatable food and supportive environments in reducing central stress responses.

  6. Environmental enrichment and cafeteria diet attenuate the response to chronic variable stress in rats.

    PubMed

    Zeeni, N; Bassil, M; Fromentin, G; Chaumontet, C; Darcel, N; Tome, D; Daher, C F

    2015-02-01

    Exposure to an enriched environment (EE) or the intake of a highly palatable diet may reduce the response to chronic stress in rodents. To further explore the relationships between EE, dietary intake and stress, male Sprague-Dawley rats were fed one of two diets for 5 weeks: high carbohydrate (HC) or "cafeteria" (CAF) (Standard HC plus a choice of highly palatable cafeteria foods: chocolate, biscuits, and peanut butter). In addition, they were either housed in empty cages or cages with EE. After the first two weeks, half of the animals from each group were stressed daily using a chronic variable stress (CVS) paradigm, while the other half were kept undisturbed. Rats were sacrificed at the end of the 5-week period. The effects of stress, enrichment and dietary intake on animal adiposity, serum lipids, and stress hormones were analyzed. Results showed an increase in intra-abdominal fat associated with the CAF diet and an increase in body weight gain associated with both the CAF diet and EE. Furthermore, the increase in ACTH associated with CVS was attenuated in the presence of EE and the CAF diet independently while the stress-induced increase in corticosterone was reduced by the combination of EE and CAF feeding. The present study provides evidence that the availability of a positive environment combined to a highly palatable diet increases resilience to the effects of CVS in rats. These results highlight the important place of palatable food and supportive environments in reducing central stress responses. PMID:25446213

  7. The effect of acute and chronic centrophenoxine treatment on the synaptic plasticity of old rats.

    PubMed

    Bertoni-Freddari, C; Giuli, C; Pieri, C

    1982-12-01

    The cerebellar glomerulus was studied by electron microscopic morphometry in female Wistar rats. Age-dependent alterations have been revealed from 3 to 28 mth of age, and the effect of centrophenoxine (CPH) was analyzed in two different patterns of administration. First, 27-mth-old rats were treated daily for 6 wk (acute treatment), and second, 18-mth-old rats were treated 3 times per week for 5 months (chronic treatment). The dose was 100 mg CPH/kg body weight, injected intraperitoneally. The surface density (SV), the numerical density (NV) and the average length (L) of the synaptic junctions were calculated from data obtained on ethanol-phosphotungstic acid stained ultrathin sections. An age-dependent reduction of SV and NV of the synaptic contact zones was found, and the L increased in the oldest animals. CPH-treatment resulted in a marked increase of SV in both types of application, whereas the other two parameters behaved differently in the two groups. The chronic treatment resulted in a significant slowing down of the decrease of NV, whereas L remained invariate. On the contrary, the acute treatment increased L but did not alter significantly NV. The results and the differences between the treatment types are discussed in terms of synaptic plasticity and are interpreted as different manifestations of the same reactive synaptogenetic process.

  8. Urinary concentrating mechanism and Aquaporin-2 abundance in rats chronically treated with aluminum lactate.

    PubMed

    Mahieu, Stella; Millen, Néstor; Contini, María del Carmen; Gonzalez, Marcela; Molinas, Sara M; Elías, María Mónica

    2006-06-15

    The aim of this work was to study the effects of chronic administration of aluminum (Al) on the urinary concentrating and diluting mechanisms in the distal tubules and collecting ducts. Male Wistar rats were chronically treated with aluminum lactate for 12 weeks (0.575 mg Al/100g of body weight, i.p., three times per week). After 12 weeks, renal function of control and Al-treated rats was evaluated by clearance techniques. To study urinary concentrating mechanisms, renal function was also measured in control and Al-treated rats deprived of water, after the administration of desmopressin (vasopressin agonist) and after the infusion of hypertonic saline at increasing infusion rates. Sodium and water balance were impaired. We found decreased urinary concentrating ability in situations in which endogenous (thirst or infusion of hypertonic saline) or exogenous plasma antidiuretic hormone was increased. Solute-free water formation, measured during the infusion of hypotonic saline showed normal transport in the thick ascending limb. Aquaporin-2 (AQP2) expression was measured by Western blot to evaluate water permeability in collecting ducts. We found that Al produced downregulation of AQP2 in plasma membranes and intracellular vesicles, that could account for the impaired water handling. Administration of desmopressin increased AQP2 in plasma membranes, suggesting that Al did not impair trafficking of this protein, but could interfere with AQP2 synthesis. PMID:16675087

  9. Urinary concentrating mechanism and Aquaporin-2 abundance in rats chronically treated with aluminum lactate.

    PubMed

    Mahieu, Stella; Millen, Néstor; Contini, María del Carmen; Gonzalez, Marcela; Molinas, Sara M; Elías, María Mónica

    2006-06-15

    The aim of this work was to study the effects of chronic administration of aluminum (Al) on the urinary concentrating and diluting mechanisms in the distal tubules and collecting ducts. Male Wistar rats were chronically treated with aluminum lactate for 12 weeks (0.575 mg Al/100g of body weight, i.p., three times per week). After 12 weeks, renal function of control and Al-treated rats was evaluated by clearance techniques. To study urinary concentrating mechanisms, renal function was also measured in control and Al-treated rats deprived of water, after the administration of desmopressin (vasopressin agonist) and after the infusion of hypertonic saline at increasing infusion rates. Sodium and water balance were impaired. We found decreased urinary concentrating ability in situations in which endogenous (thirst or infusion of hypertonic saline) or exogenous plasma antidiuretic hormone was increased. Solute-free water formation, measured during the infusion of hypotonic saline showed normal transport in the thick ascending limb. Aquaporin-2 (AQP2) expression was measured by Western blot to evaluate water permeability in collecting ducts. We found that Al produced downregulation of AQP2 in plasma membranes and intracellular vesicles, that could account for the impaired water handling. Administration of desmopressin increased AQP2 in plasma membranes, suggesting that Al did not impair trafficking of this protein, but could interfere with AQP2 synthesis.

  10. Chronic contamination of rats with 137 cesium radionuclide: impact on the cardiovascular system.

    PubMed

    Guéguen, Yann; Lestaevel, Philippe; Grandcolas, Line; Baudelin, Cédric; Grison, Stéphane; Jourdain, Jean-René; Gourmelon, Patrick; Souidi, Maâmar

    2008-03-01

    Cardiovascular system impairment has been observed in children and in liquidators exposed to the Chernobyl nuclear power plant accident. No experimental studies of animals have analyzed whether these disorders might be attributed to chronic ingestion of low levels of cesium 137 ((137)Cs). Biochemical, physiological, and molecular markers of the cardiovascular system were analyzed in rats exposed through drinking water to (137)Cs at a dose of 500 Bq kg(-1) (6500 Bq l(-1)). Plasma concentrations of CK and CK-MB were higher (+52%, P < 0.05) in contaminated rats. No histological alteration of the heart was observed, but gene expression was modified in the atria. Specifically, levels of ACE (angiotensin converting enzyme) and BNP (brain natriuretic peptide) gene expression increased significantly (P < 0.05). ECG analysis did not disclose any arrhythmia except ST- and RT-segment shortening (-9% and -11%, respectively, P < 0.05) in rats exposed to (137)Cs. Mean blood pressure decreased (-10%, P < 0.05), and its circadian rhythm disappeared. Overall, chronic contamination by an extreme environmental dose of (137)Cs for 3 months did not result in cardiac morphological changes, but the cardiovascular system impairments we observed could develop into more significant changes in sensitive animals or after longer contamination.

  11. Forced treadmill exercise prevents oxidative stress and memory deficits following chronic cerebral hypoperfusion in the rat.

    PubMed

    Cechetti, Fernanda; Worm, Paulo Valdeci; Elsner, Viviane Rostirolla; Bertoldi, Karine; Sanches, Eduardo; Ben, Juliana; Siqueira, Ionara Rodrigues; Netto, Carlos Alexandre

    2012-01-01

    Physical activity impacts functional recovery following stroke in humans, however its effects in experimental animals submitted to chronic cerebral hypoperfusion have not been investigated. The aim of this study was to evaluate the therapeutic potential of exercise, as assessed by cognitive activity in the Morris water maze and the brain oxidative status, through measurement of macromolecules damage, TBARS levels and total cellular thiols, as well as antioxidant enzymes in hippocampus, striatum and cerebral cortex. Adult male Wistar rats were submitted to the modified permanent bilateral occlusion of the common carotid arteries (2VO) method, with right common carotid artery being first occluded, and tested 3 months after the ischemic event. The effects of three different exercise protocols were examined: pre-ischemia, post-ischemia and pre+post-ischemia. Physical exercise consisted of sessions of 20-min, 3 times per week during 12 weeks (moderate intensity). Rats were submitted to cognitive assessment, in both reference and working spatial memory and after the last testing session were sacrificed to have oxidative stress parameters determined. Hypoperfusion caused a significant cognitive deficit in both spatial water maze tasks and this effect was reversed in rats receiving exercise protocol post and pre+post the ischemic event. Moreover, forced regular treadmill exercise regulated oxidative damage and antioxidant enzyme activity in the hippocampus. These results suggest that physical exercise protects against cognitive and biochemical impairments caused by chronic cerebral hypoperfusion.

  12. Preventive and therapeutic effect of treadmill running on chronic stress-induced memory deficit in rats.

    PubMed

    Radahmadi, Maryam; Alaei, Hojjatallah; Sharifi, Mohammad Reza; Hosseini, Nasrin

    2015-04-01

    Previous results indicated that stress impairs learning and memory. In this research, the effects of preventive, therapeutic and regular continually running activity on chronic stress-induced memory deficit in rats were investigated. 70 male rats were randomly divided into seven groups as follows: Control, Sham, Stress-Rest, Rest-Stress, Stress-Exercise, Exercise-Stress and Exercise-Stress & Exercise groups. Chronic restraint stress was applied 6 h/day for 21days and treadmill running 1 h/day. Memory function was evaluated by the passive avoidance test. The results revealed that running activities had therapeutic effect on mid and long-term memory deficit and preventive effects on short and mid-term memory deficit in stressed rats. Regular continually running activity improved mid and long-term memory compared to Exercise-Stress group. The beneficial effects of exercise were time-dependent in stress conditions. Finally, data corresponded to the possibility that treadmill running had a more important role on treatment rather than on prevention on memory impairment induced by stress.

  13. IB4-saporin attenuates acute and eliminates chronic muscle pain in the rat.

    PubMed

    Alvarez, Pedro; Gear, Robert W; Green, Paul G; Levine, Jon D

    2012-02-01

    The function of populations of nociceptors in muscle pain syndromes remain poorly understood. We compared the contribution of two major classes, isolectin B4-positive (IB4(+)) and IB4-negative (IB4(-)) nociceptors, in acute and chronic inflammatory and ergonomic muscle pain. Baseline mechanical nociceptive threshold was assessed in the gastrocnemius muscle of rats treated with IB4-saporin, which selectively destroys IB4(+) nociceptors. Rats were then submitted to models of acute inflammatory (intramuscular carrageenan)- or ergonomic intervention (eccentric exercise or vibration)-induced muscle pain, and each of the three models also evaluated for the transition from acute to chronic pain, manifest as prolongation of prostaglandin E2 (PGE(2))-induced hyperalgesia, after recovery from the hyperalgesia induced by acute inflammation or ergonomic interventions. IB4-saporin treatment did not affect baseline mechanical nociceptive threshold. However, compared to controls, IB4-saporin treated rats exhibited shorter duration mechanical hyperalgesia in all three models and attenuated peak hyperalgesia in the ergonomic pain models. And, IB4-saporin treatment completely prevented prolongation of PGE(2)-induced mechanical hyperalgesia. Thus, IB4(+) and IB4(-) neurons contribute to acute muscle hyperalgesia induced by diverse insults. However, only IB4+ nociceptors participate in the long term consequence of acute hyperalgesia.

  14. Chronic Treatment with Ivabradine Does Not Affect Cardiovascular Autonomic Control in Rats.

    PubMed

    Silva, Fernanda C; Paiva, Franciny A; Müller-Ribeiro, Flávia C; Caldeira, Henrique M A; Fontes, Marco A P; de Menezes, Rodrigo C A; Casali, Karina R; Fortes, Gláucia H; Tobaldini, Eleonora; Solbiati, Monica; Montano, Nicola; Dias Da Silva, Valdo J; Chianca, Deoclécio A

    2016-01-01

    A low resting heart rate (HR) would be of great benefit in cardiovascular diseases. Ivabradine-a novel selective inhibitor of hyperpolarization-activated cyclic nucleotide gated (HCN) channels- has emerged as a promising HR lowering drug. Its effects on the autonomic HR control are little known. This study assessed the effects of chronic treatment with ivabradine on the modulatory, reflex and tonic cardiovascular autonomic control and on the renal sympathetic nerve activity (RSNA). Male Wistar rats were divided in 2 groups, receiving intraperitoneal injections of vehicle (VEH) or ivabradine (IVA) during 7 or 8 consecutive days. Rats were submitted to vessels cannulation to perform arterial blood pressure (AP) and HR recordings in freely moving rats. Time series of resting pulse interval and systolic AP were used to measure cardiovascular variability parameters. We also assessed the baroreflex, chemoreflex and the Bezold-Jarish reflex sensitivities. To better evaluate the effects of ivabradine on the autonomic control of the heart, we performed sympathetic and vagal autonomic blockade. As expected, ivabradine-treated rats showed a lower resting (VEH: 362 ± 16 bpm vs. IVA: 260 ± 14 bpm, p = 0.0005) and intrinsic HR (VEH: 369 ± 9 bpm vs. IVA: 326 ± 11 bpm, p = 0.0146). However, the chronic treatment with ivabradine did not change normalized HR spectral parameters LF (nu) (VEH: 24.2 ± 4.6 vs. IVA: 29.8 ± 6.4; p > 0.05); HF (nu) (VEH: 75.1 ± 3.7 vs. IVA: 69.2 ± 5.8; p > 0.05), any cardiovascular reflexes, neither the tonic autonomic control of the HR (tonic sympathovagal index; VEH: 0.91± 0.02 vs. IVA: 0.88 ± 0.03, p = 0.3494). We performed the AP, HR and RSNA recordings in urethane-anesthetized rats. The chronic treatment with ivabradine reduced the resting HR (VEH: 364 ± 12 bpm vs. IVA: 207 ± 11 bpm, p < 0.0001), without affecting RSNA (VEH: 117 ± 16 vs. IVA: 120 ± 9 spikes/s, p = 0.9100) and mean arterial pressure (VEH: 70 ± 4 vs. IVA: 77 ± 6 mmHg, p

  15. Chronic Treatment with Ivabradine Does Not Affect Cardiovascular Autonomic Control in Rats

    PubMed Central

    Silva, Fernanda C.; Paiva, Franciny A.; Müller-Ribeiro, Flávia C.; Caldeira, Henrique M. A.; Fontes, Marco A. P.; de Menezes, Rodrigo C. A.; Casali, Karina R.; Fortes, Gláucia H.; Tobaldini, Eleonora; Solbiati, Monica; Montano, Nicola; Dias Da Silva, Valdo J.; Chianca, Deoclécio A.

    2016-01-01

    A low resting heart rate (HR) would be of great benefit in cardiovascular diseases. Ivabradine—a novel selective inhibitor of hyperpolarization-activated cyclic nucleotide gated (HCN) channels- has emerged as a promising HR lowering drug. Its effects on the autonomic HR control are little known. This study assessed the effects of chronic treatment with ivabradine on the modulatory, reflex and tonic cardiovascular autonomic control and on the renal sympathetic nerve activity (RSNA). Male Wistar rats were divided in 2 groups, receiving intraperitoneal injections of vehicle (VEH) or ivabradine (IVA) during 7 or 8 consecutive days. Rats were submitted to vessels cannulation to perform arterial blood pressure (AP) and HR recordings in freely moving rats. Time series of resting pulse interval and systolic AP were used to measure cardiovascular variability parameters. We also assessed the baroreflex, chemoreflex and the Bezold-Jarish reflex sensitivities. To better evaluate the effects of ivabradine on the autonomic control of the heart, we performed sympathetic and vagal autonomic blockade. As expected, ivabradine-treated rats showed a lower resting (VEH: 362 ± 16 bpm vs. IVA: 260 ± 14 bpm, p = 0.0005) and intrinsic HR (VEH: 369 ± 9 bpm vs. IVA: 326 ± 11 bpm, p = 0.0146). However, the chronic treatment with ivabradine did not change normalized HR spectral parameters LF (nu) (VEH: 24.2 ± 4.6 vs. IVA: 29.8 ± 6.4; p > 0.05); HF (nu) (VEH: 75.1 ± 3.7 vs. IVA: 69.2 ± 5.8; p > 0.05), any cardiovascular reflexes, neither the tonic autonomic control of the HR (tonic sympathovagal index; VEH: 0.91± 0.02 vs. IVA: 0.88 ± 0.03, p = 0.3494). We performed the AP, HR and RSNA recordings in urethane-anesthetized rats. The chronic treatment with ivabradine reduced the resting HR (VEH: 364 ± 12 bpm vs. IVA: 207 ± 11 bpm, p < 0.0001), without affecting RSNA (VEH: 117 ± 16 vs. IVA: 120 ± 9 spikes/s, p = 0.9100) and mean arterial pressure (VEH: 70 ± 4 vs. IVA: 77 ± 6 mm

  16. Behavioral responses in rats submitted to chronic administration of branched-chain amino acids.

    PubMed

    Scaini, Giselli; Jeremias, Gabriela C; Furlanetto, Camila B; Dominguini, Diogo; Comim, Clarissa M; Quevedo, João; Schuck, Patrícia F; Ferreira, Gustavo C; Streck, Emilio L

    2014-01-01

    Maple syrup urine disease (MSUD) is an inborn metabolism error caused by a deficiency of branched-chain α-keto acid dehydrogenase complex activity. This blockage leads to an accumulation of the branched-chain amino acids (BCAA) leucine, isoleucine, and valine, as well as their corresponding α-keto and α-hydroxy acids. Previous reports suggest that MSUD patients are at high risk for chronic neuropsychiatric problems. Therefore, in this study, we assessed variables that suggest depressive-like symptoms (anhedonia as measured by sucrose intake, immobility during the forced swimming test and body and adrenal gland weight) in rats submitted to chronic administration of BCAA during development. Furthermore, we determined if these parameters were sensitive to imipramine and N-acetylcysteine/deferoxamine (NAC/DFX). Our results demonstrated that animals subjected to chronic administration of branched-chain amino acids showed a decrease in sucrose intake without significant changes in body weight. We also observed an increase in adrenal gland weight and immobility time during the forced swimming test. However, treatment with imipramine and NAC/DFX reversed these changes in the behavioral tasks. In conclusion, this study demonstrates a link between MSUD and depression in rats. Moreover, this investigation reveals that the antidepressant action of NAC/DFX and imipramine might be associated with their capability to maintain pro-/anti-oxidative homeostasis. PMID:24214724

  17. Effects of Chinese medicinal herbs on a rat model of chronic Pseudomonas aeruginosa lung infection.

    PubMed

    Song, Z; Johansen, H K; Moser, C; Høiby, N

    1996-05-01

    The aim of the study was to evaluate the effects of two kinds of Chinese medicinal herbs, Isatis tinctoria L (ITL) and Daphne giraldii Nitsche (DGN), on a rat model of chronic Pseudomonas aeruginosa lung infection mimicking cystic fibrosis (CF). Compared to the control group, both drugs were able to reduce the incidence of lung abscess (p < 0.05) and to decrease the severity of the macroscopic pathology in lungs (p < 0.05). In the great majority of the rats, the herbs altered the inflammatory response in the lungs from an acute type inflammation, dominated by polymorphonuclear leukocytes (PMN), to a chronic type inflammation, dominated by mononuclear leukocytes (MN). DGN also improved the clearance of P. aeruginosa from the lungs (p < 0.03) compared with the control group. There were no significant differences between the control group and the two herbal groups with regard to serum IgG and IgA anti-P. aeruginosa sonicate antibodies. However, the IgM concentration in the ITL group was significantly lower than in the control group (p < 0.03). These results suggest that the two medicinal herbs might be helpful to CF patients with chronic P. aeruginosa lung infection, DGN being the most favorable. PMID:8703440

  18. Depression of biliary glutathione excretion by chronic ethanol feeding in the rat

    SciTech Connect

    Vendemiale, G.; Jayatilleke, E.; Shaw, S.; Lieber, C.S.

    1984-03-12

    The effects of chronic alcohol feeding on biliary glutathione excretion were studied in rats pair fed diets containing either ethanol (36% of total energy) or isocaloric carbohydrate for 4-6 weeks. An exteriorized biliary-duodenal fistula was established and total glutathione (GSH) and oxidized glutathione (GSSG) were measured. A significant decrease was observed in rats fed alcohol chronically compared to their pair fed controls in the biliary excretion of GSH (55.7 +/- 37.0 vs 243.1 +/- 29.0 ..mu..g/ml bile, p < 0.025) as well as biliary GSSG (12.5 +/- 5.0 vs 49.9 +/- 8.0 ..mu..g/ml bile, p < 0.05) and in bile flow (23.1 +/- 1.6 vs 29.2 +/- 1.3 ..mu..g/min, p < 0.05). An acute dose of ethanol tended to exaggerate the decrease on biliary GSH and GSSG in the two groups of animals. The depression in biliary GSH could not be attributed to decreased GSH synthesis since S/sup 35/-L-methionine incorporation into hepatic and biliary GSH was unchanged or even increased after chronic ethanol feeding. 22 references, 4 figures.

  19. Changes in contractile properties of skinned single rat soleus and diaphragm fibres after chronic hypoxia.

    PubMed

    Degens, Hans; Bosutti, Alessandra; Gilliver, Sally F; Slevin, Mark; van Heijst, Arno; Wüst, Rob C I

    2010-10-01

    Hypoxia may be one of the factors underlying muscle dysfunction during ageing and chronic lung and heart failure. Here we tested the hypothesis that chronic hypoxia per se affects contractile properties of single fibres of the soleus and diaphragm muscle. To do this, the force-velocity relationship, rate of force redevelopment and calcium sensitivity of single skinned fibres from normoxic rats and rats exposed to 4 weeks of hypobaric hypoxia (410 mmHg) were investigated. The reduction in maximal force (P(0)) after hypoxia (p=0.031) was more pronounced in type IIa than type I fibres and was mainly attributable to a reduction in fibre cross-sectional area (p=0.044). In type IIa fibres this was aggravated by a reduction in specific tension (p=0.001). The maximal velocity of shortening (V (max)) and shape of the force velocity relation (a/P(0)), however, did not differ between normoxic and hypoxic muscle fibres and the reduction in maximal power of hypoxic fibres (p=0.012) was mainly due to a reduction in P(0). In conclusion, chronic hypoxia causes muscle fibre dysfunction which is not only due to a loss of muscle mass, but also to a diminished force generating capacity of the remaining contractile material. These effects are similar in the soleus and diaphragm muscle, but more pronounced in type IIa than I fibres. PMID:20697736

  20. Investigation of redox status in chronic cerebral hypoperfusion-induced neurodegeneration in rats

    PubMed Central

    Saxena, Anil Kumar; Abdul-Majeed, Saif Saad; Gurtu, Sunil; Mohamed, Wael M.Y.

    2015-01-01

    Aging related reduction in cerebral blood flow (CBF) has been linked with neurodegenerative disorders including Alzheimer's disease and dementia. Experimentally, a condition of chronic cerebral hypoperfusion due to reduced CBF can be induced by permanent bilateral occlusion of common carotid arteries (2-vessel occlusion, 2VO) in rats. Since oxidative stress, leading to neuronal apoptosis and death, is one of the mechanisms, which is thought to play a significant role in chronic degenerative neurological disorders, the present study was planned to assess the ROS status by measuring the levels of anti-oxidant enzymes that might occur during chronic cerebral hypoperfusion. Antioxidant enzymes namely glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase were measured in the brain tissue at eight weeks of 2VO induction in rats. Results show significantly elevated levels of GPx, SOD, and catalase enzymes as compared with the control group. It is possible that compensatory rise in antioxidant enzymes occurs in response to increased oxidative stress following ischemic insult. PMID:26937356

  1. THERMAL SENSITIVITY ACROSS AGES AND DURING CHRONIC FENTANYL ADMINISTRATION IN RATS

    PubMed Central

    Mitzelfelt, Jeremiah D.; Carter, Christy S.; Morgan, Drake

    2013-01-01

    Rationale Chronic pain is becoming a more common medical diagnosis and is especially prevalent in older individuals. As such, prescribed use of opioids is on the rise, even though the efficacy for pain management in older individuals is unclear. Objectives Thus the present preclinical study assessed the effectiveness of chronic fentanyl administration to produce antinociception in aging rats (16, 20, 24 months). Methods Animals were tested in a thermal sensitivity procedure known to involve neural circuits implicated in chronic pain in humans. Sensitivity to heat and cold thermal stimulation was assessed during 28 days of fentanyl administration (1.0 mg/kg/day), and 28 days of withdrawal. Results Fentanyl resulted in decreased thermal sensitivity to heat but not cold stimulation indicated by more time spent in the hot compartment relative to time spent in the cold or neutral compartments. Unlike previous findings using a hot-water tail withdrawal procedure, tolerance did not develop to the antinociceptive effects of fentanyl over a 28-day period of drug administration. The oldest animals were least sensitive, and the youngest animals most sensitive to the locomotor-stimulating effects of fentanyl. The effect on the antinociceptive response to fentanyl in the oldest group of rats was difficult to interpret due to profound changes in the behavior of saline-treated animals. Conclusions Overall, aging modifies the behavioral effects of opioids, a finding that may inform future studies for devising appropriate treatment strategies. PMID:23900640

  2. Interactions between methaqualone and ethanol in rats and mice during acute and chronic states.

    PubMed

    Ho, C C; Ho, A K

    1978-01-01

    1. The effects of acute and chronic treatment of methaqualone on ethanol preference, the rate of disappearance of ethanol and on toxicity were studied in mice and rats. 2. Acute treatment with methaqualone showed a dose-dependent suppression in the voluntary intake of ethanol in C57Bl/6J mice in rats. No significant change in ethanol intake was observed during chronic methaqualone treatment and withdrawal. 3. Methaqualone pretreatment significantly (P less than 0.005) delayed the disappearance of ethanol in the blood and brain over a period of 50 and 200 min after a loading dose of 2.0 g/kg, i.p., of ethanol. 4. Methaqualone pretreatment at doses of 140 and 200 mg/kg significantly increased ethanol toxicity by 11% and 28%, respectively. Co-administration of ethanol using 6.0, 7.0 and 8.0 g/kg also reduced the LD50 of methaqualone by 19%, 24% and 40%, respectively. 5. Chronic administration with ethanol decreased the toxicity due to methaqualone. Potentiation of ethanol toxicity by methaqualone may be of clinical importance in view of the narrow range of safety margin of ethanol.

  3. The effects of acute and chronic stress on motor and sensory performance in male Lewis rats.

    PubMed

    Metz, G A; Schwab, M E; Welzl, H

    2001-01-01

    Any behavioral testing induces stress to some degree. A meaningful interpretation of behavioral results can be difficult if stress, caused by handling or the testing situation, modifies the experimental outcome. Especially for neurological animal models, it is important to know how stress affects motor and sensory performance. Therefore, we investigated the effects of varying degrees of stress on several motor and sensory tasks that are frequently used to assess functional recovery after lesion-induced impairments in adult rats. Acute, subchronic, and chronic stress impaired ladder walking and prolonged the duration of grasping a bar. Stress also altered walking patterns by increasing the base of support and foot rotation and reducing stride length. Furthermore, chronic stress induced hypersensitivity to painful stimuli, but did not significantly influence the latency to remove sticky papers from the hindpaws (sticky paper test). In the light--dark (L/D) test, stress reduced the latency to enter the dark compartment and enhanced the number of transitions supporting that cold swim stress modifies the animal's level of anxiety. These data point towards a critical influence of acute or chronic stress on motor control and sensory performance of rats, suggesting that stress might be a critical intervening variable of the outcome of behavioral tests. PMID:11239978

  4. Preventive effect of cimetidine on chronic erosive gastritis induced by taurocholate in rats.

    PubMed

    Kishimoto, S; Kobuke, K; Kobayashi, H; Kajiyama, G; Miyoshi, A; Daitoku, K

    1991-01-01

    We studied the preventive effect of cimetidine at the microscopic level on chronic erosive gastritis induced experimentally by 6-months of administration of drinking water containing 5 mmol/l of the sodium salt of taurocholic acid (TCA) in rats. The chronic erosive gastritis was characterized by mucosal erosions, reduction of mucosal thickness and reduction in the number of parietal cells per unit area, infiltration of inflammatory cells which were mainly lymphocytes and plasmocytes, and proliferation of collagenous fibers in the gastric mucosa. A standard meal including cimetidine 0.4 and 0.8%, which was administered ad libitum with TCA, reduced the total length of erosions, normalized the mucosal thickness and the number of parietal cells, and reduced inflammatory cell infiltration in the gastric mucosa. However, cimetidine did not show any effect on the proliferation of collagenous fibers in the interstitial space of the mucosa. The doses administered were 400 mg/kg/day and 800 mg/kg/day for 6 months. Cimetidine, thus, had a preventive effect on experimental chronic erosive gastritis in rats. PMID:2024066

  5. Chronic stress, cyclic 17β-estradiol, and daily handling influences on fear conditioning in the female rat.

    PubMed

    Hoffman, Ann N; Armstrong, Charles E; Hanna, Jeffery J; Conrad, Cheryl D

    2010-10-01

    Chronic stress and estrogens alter many forebrain regions in female rats that affect cognition. In order to investigate how chronic stress and estrogens influence fear learning and memory, we ovariectomized (OVX) female Sprague-Dawley rats and repeatedly injected them (s.c.) with 17β-estradiol (E, 10 μg/250 g or sesame oil vehicle, VEH). Concurrently, rats were restrained for 6 h/d/21 d (STR) or left undisturbed (CON). Rats were then fear conditioned with 4 tone-footshock pairings and then after 1 h and 24 h delays, given 15 tone extinction trials. Regardless of E treatment, chronic stress (VEH, E) facilitated freezing to tone during acquisition and extinction following a 1h delay, but not during extinction after a 24 h delay. E did not influence freezing to tone during any phase of fear conditioning for either the control or chronically stressed rats, but did influence contextual conditioning that may have been carried predominately by the STR group. In the second experiment, we investigated "handling" influences on fear conditioning acquisition, given the disparate findings from the current study and previous work (Baran, Armstrong, Niren, & Conrad, 2010; Baran, Armstrong, Niren, Hanna, & Conrad, 2009). Female rats remained gonadally-intact since E did not influence tone fear conditioning. Indeed, brief daily handling (1-3 m/d/21 d) facilitated acquisition of fear conditioning in chronically stressed female rats, and either had no effect or slightly attenuated fear conditioning in controls. Thus, chronic stress impacts amygdala-mediated fear learning in both OVX- and gonadally-intact females as found previously in males, with handling significantly influencing these outcomes.

  6. Therapy effect of antiulcer agents on new chronic cysteamine colon lesion in rat.

    PubMed

    Sikiric, P; Seiwerth, S; Aralica, G; Perovic, D; Staresinic, M; Anic, T; Gjurasin, M; Prkacin, I; Separovic, J; Stancic-Rokotov, D; Lovric-Bencic, M; Mikus, D; Turkovic, B; Rotkvic, I; Mise, S; Rucman, R; Petek, M; Ziger, T; Sebecic, B; Ivasovic, Z; Jagic, V; Komericki, L; Balen, I; Boban-Blagaic, A; Sjekavica, I

    2001-01-01

    After demonstration that cysteamine induced duodenal lesions in gastrectomized rats, while a number of antiulcer drugs mitigated these lesions, it was shown that one single intrarectal (i.r.) cysteamine application produced severe colon lesions in acute studies in rats. Thus, the further focus was on the protracted effect of cysteamine challenge (400 mg/kg b.w. i.r.) and therapy influence in chronic experiments in female rats. Regularly, cysteamine colon lesions were markedly mitigated by ranitidine (10), omeprazole (10), atropine (10), methylprednisolone (1), sulphasalazine (50; mg/kg), pentadecapeptide BPC 157 (PL-10, PLD-116; 10 microg or 10 ng/kg). Specifically, after 1 or 3 months following initial challenge (cysteamine 400 mg/kg i.r.) in female rat, the therapy [BPC 157 (PL-10, PLD-116 (10.0 microg or 10.0 ng/kg; i.g., i.p., i.r.), ranitidine, omeprazole, atropine, methylprednisolone, sulphasalazine (i.p.)] reversed the protracted cysteamine colon injury: the 1 week-regimen (once daily application) started after 1 month post-cysteamine, as well as the 2 weeks-regimen (once daily application), which started after 3 months. The effect on recidive lesion was also tested. These cysteamine lesions may reappear after stopping therapy (after stopping therapy for 3 weeks at the end of 2-weeks regimen started in 3 months-cysteamine female rats) in sulphasalazine group, while this reappearance is markedly antagonized in pentadecapeptide BPC 157 (PL-10, PLD-116)-rats (cysteamine-colon lesion still substantially low). PMID:11595451

  7. Contrasting effects of chronic ethanol feeding on centrally and peripherally evoked hypotension in telemetered female rats.

    PubMed

    El-Mas, Mahmoud M; Abdel-Rahman, Abdel A

    2004-03-01

    Our previous studies have shown that ethanol compromises hypotension produced by centrally acting antihypertensive agents in normotensive and hypertensive male rats. The present study investigated whether female rats are as susceptible as male rats to the deleterious effect of ethanol on centrally evoked hypotension. The study was extended to investigate ethanol effects on the time-domain indices of variability in blood pressure [standard deviation of mean arterial pressure (SDMAP)] and heart rate [standard deviation of beat-to-beat intervals (SDRR) and root mean square of successive differences in R-R intervals (rMSSD)]. The hemodynamic effects of a single intraperitoneal dose of clonidine (30 microg/kg) were evaluated in radiotelemetered ethanol-fed (5%, 12 weeks) and pair-fed control Sprague-Dawley rats. In control rats, clonidine caused a significant reduction in MAP that continued for at least 6 h and was associated with reductions in SDMAP and SDRR but not rMSSD, suggesting inhibition of central sympathetic tone. A maximum hypotensive response of -16.4+/-1.7 mm Hg was demonstrated 40 min after clonidine administration. Ethanol feeding significantly attenuated clonidine hypotension whereas it potentiated the associated reduction in SDMAP. To verify the selectivity of ethanol-clonidine interaction, the effects of ethanol on peripherally mediated hemodynamic responses to hydralazine (0.5 mg/kg ip) were investigated. In contrast to its antagonistic effect on clonidine hypotension, ethanol significantly potentiated the hypotensive effect of hydralazine. Together, these findings demonstrate that chronic ethanol feeding exerts opposite effects on centrally (attenuation) and peripherally (potentiation) evoked hypotension in female rats. The interaction of ethanol with antihypertensive agents may not be related to changes in hemodynamic variability.

  8. Chronic ingestion of 2-deoxy-D-glucose induces cardiac vacuolization and increases mortality in rats

    SciTech Connect

    Minor, Robin K.; Smith, Daniel L.; Sossong, Alex M.; Kaushik, Susmita; Poosala, Suresh; Spangler, Edward L.; Roth, George S.; Lane, Mark; Allison, David B.; Cabo, Rafael de; Ingram, Donald K.; Mattison, Julie A.

    2010-03-15

    Calorie restriction (CR), the purposeful reduction of energy intake with maintenance of adequate micronutrient intake, is well known to extend the lifespan of laboratory animals. Compounds like 2-deoxy-D-glucose (2DG) that can recapitulate the metabolic effects of CR are of great interest for their potential to extend lifespan. 2DG treatment has been shown to have potential therapeutic benefits for treating cancer and seizures. 2DG has also recapitulated some hallmarks of the CR phenotype including reduced body temperature and circulating insulin in short-term rodent trials, but one chronic feeding study in rats found toxic effects. The present studies were performed to further explore the long-term effects of 2DG in vivo. First we demonstrate that 2DG increases mortality of male Fischer-344 rats. Increased incidence of pheochromocytoma in the adrenal medulla was also noted in the 2DG treated rats. We reconfirm the cardiotoxicity of 2DG in a 6-week follow-up study evaluating male Brown Norway rats and a natural form of 2DG in addition to again examining effects in Fischer-344 rats and the original synthetic 2DG. High levels of both 2DG sources reduced weight gain secondary to reduced food intake in both strains. Histopathological analysis of the hearts revealed increasing vacuolarization of cardiac myocytes with dose, and tissue staining revealed the vacuoles were free of both glycogen and lipid. We did, however, observe higher expression of both cathepsin D and LC3 in the hearts of 2DG-treated rats which indicates an increase in autophagic flux. Although a remarkable CR-like phenotype can be reproduced with 2DG treatment, the ultimate toxicity of 2DG seriously challenges 2DG as a potential CR mimetic in mammals and also raises concerns about other therapeutic applications of the compound.

  9. Possible cause for altered spatial cognition of prepubescent rats exposed to chronic radiofrequency electromagnetic radiation.

    PubMed

    Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Karun, Kalesh M; Nayak, Satheesha B; Bhat, P Gopalakrishna

    2015-10-01

    The effects of chronic and repeated radiofrequency electromagnetic radiation (RFEMR) exposure on spatial cognition and hippocampal architecture were investigated in prepubescent rats. Four weeks old male Wistar rats were exposed to RF-EMR (900 MHz; SAR-1.15 W/kg with peak power density of 146.60 μW/cm(2)) for 1 h/day, for 28 days. Followed by this, spatial cognition was evaluated by Morris water maze test. To evaluate the hippocampal morphology; H&E staining, cresyl violet staining, and Golgi-Cox staining were performed on hippocampal sections. CA3 pyramidal neuron morphology and surviving neuron count (in CA3 region) were studied using H&E and cresyl violet stained sections. Dendritic arborization pattern of CA3 pyramidal neuron was investigated by concentric circle method. Progressive learning abilities were found to be decreased in RF-EMR exposed rats. Memory retention test performed 24 h after the last training revealed minor spatial memory deficit in RF-EMR exposed group. However, RF-EMR exposed rats exhibited poor spatial memory retention when tested 48 h after the final trial. Hirano bodies and Granulovacuolar bodies were absent in the CA3 pyramidal neurons of different groups studied. Nevertheless, RF-EMR exposure affected the viable cell count in dorsal hippocampal CA3 region. RF-EMR exposure influenced dendritic arborization pattern of both apical and basal dendritic trees in RF-EMR exposed rats. Structural changes found in the hippocampus of RF-EMR exposed rats could be one of the possible reasons for altered cognition. PMID:26033310

  10. Chronic ingestion of 2-deoxy-D-glucose induces cardiac vacuolization and increases mortality in rats

    PubMed Central

    Minor, Robin K.; Smith, Daniel L.; Sossong, Alex M.; Kaushik, Susmita; Poosala, Suresh; Spangler, Edward L.; Roth, George S.; Lane, Mark; Allison, David B.; de Cabo, Rafael; Ingram, Donald K.; Mattison, Julie A.

    2009-01-01

    Calorie restriction (CR), the purposeful reduction of energy intake with maintenance of adequate micronutrient intake, is well known to extend the lifespan of laboratory animals. Compounds like 2-deoxy-D-glucose (2DG) that can recapitulate the metabolic effects of CR are of great interest for their potential to extend lifespan. 2DG treatment has been shown to have potential therapeutic benefits for treating cancer and seizures. 2DG has also recapitulated some hallmarks of the CR phenotype including reduced body temperature and circulating insulin in short-term rodent trials, but one chronic feeding study in rats found toxic effects. The present studies were performed to further explore the long-term effects of 2DG in vivo. First we demonstrate that 2DG increases mortality of male Fischer-344 rats. Increased incidence of pheochromocytoma in the adrenal medulla was also noted in the 2DG treated rats. We reconfirm the cardiotoxicity of 2DG in a 6-week follow-up study evaluating male Brown Norway rats and a natural form of 2DG in addition to again examining effects in Fischer-344 rats and the original synthetic 2DG. High levels of both 2DG sources reduced weight gain secondary to reduced food intake in both strains. Histopathological analysis of the hearts revealed increasing vacuolarization of cardiac myocytes with dose, and tissue staining revealed the vacuoles were free of both glycogen and lipid. We did, however, observe higher expression of both cathepsin D and LC3 in the hearts of 2DG-treated rats which indicates an increase in autophagic flux. Although a remarkable CR-like phenotype can be reproduced with 2DG treatment, the ultimate toxicity of 2DG seriously challenges 2DG as a potential CR mimetic in mammals and also raises concerns about other therapeutic applications of the compound. PMID:20026095

  11. Possible cause for altered spatial cognition of prepubescent rats exposed to chronic radiofrequency electromagnetic radiation.

    PubMed

    Narayanan, Sareesh Naduvil; Kumar, Raju Suresh; Karun, Kalesh M; Nayak, Satheesha B; Bhat, P Gopalakrishna

    2015-10-01

    The effects of chronic and repeated radiofrequency electromagnetic radiation (RFEMR) exposure on spatial cognition and hippocampal architecture were investigated in prepubescent rats. Four weeks old male Wistar rats were exposed to RF-EMR (900 MHz; SAR-1.15 W/kg with peak power density of 146.60 μW/cm(2)) for 1 h/day, for 28 days. Followed by this, spatial cognition was evaluated by Morris water maze test. To evaluate the hippocampal morphology; H&E staining, cresyl violet staining, and Golgi-Cox staining were performed on hippocampal sections. CA3 pyramidal neuron morphology and surviving neuron count (in CA3 region) were studied using H&E and cresyl violet stained sections. Dendritic arborization pattern of CA3 pyramidal neuron was investigated by concentric circle method. Progressive learning abilities were found to be decreased in RF-EMR exposed rats. Memory retention test performed 24 h after the last training revealed minor spatial memory deficit in RF-EMR exposed group. However, RF-EMR exposed rats exhibited poor spatial memory retention when tested 48 h after the final trial. Hirano bodies and Granulovacuolar bodies were absent in the CA3 pyramidal neurons of different groups studied. Nevertheless, RF-EMR exposure affected the viable cell count in dorsal hippocampal CA3 region. RF-EMR exposure influenced dendritic arborization pattern of both apical and basal dendritic trees in RF-EMR exposed rats. Structural changes found in the hippocampus of RF-EMR exposed rats could be one of the possible reasons for altered cognition.

  12. Chronic aerobic exercise training attenuates aortic stiffening and endothelial dysfunction through preserving aortic mitochondrial function in aged rats.

    PubMed

    Gu, Qi; Wang, Bing; Zhang, Xiao-Feng; Ma, Yan-Ping; Liu, Jian-Dong; Wang, Xiao-Ze

    2014-08-01

    Aging leads to large vessel arterial stiffening and endothelial dysfunction, which are important determinants of cardiovascular risk. The aim of present work was to assess the effects of chronic aerobic exercise training on aortic stiffening and endothelial dysfunction in aged rats and investigate the underlying mechanism about mitochondrial function. Chronic aerobic exercise training attenuated aortic stiffening with age marked by reduced collagen concentration, increased elastin concentration and reduced pulse wave velocity (PWV), and prevented aging-related endothelial dysfunction marked by improved endothelium-mediated vascular relaxation of aortas in response to acetylcholine. Chronic aerobic exercise training abated oxidative stress and nitrosative stress in aortas of aged rats. More importantly, we found that chronic aerobic exercise training in old rats preserved aortic mitochondrial function marked by reduced reactive oxygen species (ROS) formation and mitochondrial swelling, increased ATP formation and mitochondrial DNA content, and restored activities of complexes I and III and electron-coupling capacity between complexes I and III and between complexes II and III. In addition, it was found that chronic aerobic exercise training in old rats enhanced protein expression of uncoupling protein 2 (UCP-2), peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), manganese superoxide dismutase (Mn-SOD), aldehyde dehydrogenase 2 (ALDH-2), prohibitin (PHB) and AMP-activated kinase (AMPK) phosphorylation in aortas. In conclusion, chronic aerobic exercise training preserved mitochondrial function in aortas, which, at least in part, explained the aorta-protecting effects of exercise training in aging.

  13. (-)-SCR1693 Protects against Memory Impairment and Hippocampal Damage in a Chronic Cerebral Hypoperfusion Rat Model

    PubMed Central

    Zhu, Xiaoyin; Tian, Jingwei; Sun, Songmei; Dong, Qiuju; Zhang, Fangxi; Zhang, Xiumei

    2016-01-01

    Chronic cerebral hypoperfusion (CCH) is one of the most common causes of vascular dementia (VaD) and is recognised as an etiological factor in the development of Alzheimer’s disease (AD). CCH can induce severe cognitive deficits, as assessed by the water maze task, along with neuronal loss in the hippocampus. However, there are currently no effective, approved pharmacological treatments available for VaD. In the present study, we created a rat model of CCH using bilateral common carotid artery occlusion and found that (-)-SCR1693, a novel compound, prevented rats from developing memory deficits and neuronal damage in the hippocampus by rectifying cholinergic dysfunction and decreasing the accumulation of the phospho-tau protein. These results strongly suggest that (-)-SCR1693 has therapeutic potential for the treatment of CCH-induced VaD. PMID:27349344

  14. Chronic lead administration in neonatal rats: electron microscopy of the retina

    SciTech Connect

    Santos-Anderson, R.M.; Tso, M.O.M.; Valdes, J.J.; Annau, Z.

    1984-03-01

    The morphologic effects on the retina resulting from chronic lead exposure were assessed in neonatal rats. Newborn rats nursed from dams were given a low (0.115%) or a high (4.5%) concentration of lead in their diet. At day 21 the pups were weaned to the mother's diet. The retinas of the pups were studied by electron microscopy at various ages up to day 60. High and low lead concentrations produced necrosis of photoreceptor cells and cells of the inner nuclear layer. The high lead concentration, in addition, was associated with swelling of endothelial cells of the retinal vessels and narrowing of the lumen. Increased permeability of the retinal vessels and pigment epithelium to horseradish peroxidase were also observed under the high-dose condition. The authors conclude that lead can produce direct neuronal damage and, at high doses, produces retinal vascular lesions and alteration of the blood-retinal barrier. 10 figures.

  15. Chronic lead administration in neonatal rats: electron microscopy of the retina

    SciTech Connect

    Santos-Anderson, R.M.; Tso, M.O.M.; Valdes, J.J.; Annau, Z.

    1984-03-01

    The morphologic effects on the retina resulting from chronic lead exposure were assessed in neonatal rats. Newborn rats nursed from dams were given a low (0.115%) or a high (4.5%) concentration of lead in their diet. At day 21 the pups were weaned to the mother's diet. The retinas of the pups were studied by electron microscopy at various ages up to day 60. High and low lead concentrations produced necrosis of photoreceptor cells and cells of the inner nuclear layer. The high lead concentration, in addition, was associated with swelling of endothelial cells of the retinal vessels and narrowing of the lumen. Increased permeability of the retinal vessels and pigment epithelium to horseradish peroxidase was also observed under the high-dose condition. The authors conclude that lead can produce direct neuronal damage and, at high doses, produces retinal vascular lesions and alteration of the blood-retinal barrier.

  16. [CHARACTERISTICS OF THE RETINA IN CHRONIC STRESS IN LABORATORY RATS OF DIFFERENT AGE GROUPS].

    PubMed

    Nesterova, A A; Yermilov, V V; Tiurenkov, I N; Smirnov, A V; Grigoriyeva, N V; Zagrebin, V L; Rogova, L N; Antoshkin, O N; Dovgalyov, A O

    2016-01-01

    The retina was studied in albino laboratory male rats of two age groups (12 and 24 months), 10 animals in each subjected to chronic combined stress. The stress was caused in animals by simultaneous exposure to pulsed light, loud sound, swinging and restriction of mobility for 7 days, 30 mm daily. The retina of intact rats of the corresponding age groups (n = 20) served as control. Enucleated eyes of stressed and control animals were processed with standard histological technique and stained with Nissl's method and hematoxylin-eosin. The retina of the stressed animals of both age groups showed the decrease in the number of cells and the disarrangement of its layers, most pronounced in the layers of photoreceptor neurons and ganglion cells. The comparative morphometric analysis demonstrated a reduction of the layer thickness and cell numerical density in the retina of stressed animals, both young (12 months) and old (24 months), as compared to that of control animals. PMID:27487662

  17. Residual effects of chronic cannabis treatment on behavior in mature rats.

    PubMed

    Stiglick, A; Kalant, H

    1985-01-01

    Mature rats (starting weight at least 270 g) were treated daily with cannabis extract (daily THC dose 20 mg/kg) for 3 months. After a 1- to 4-month drug-free period, residual effects on a variety of behaviors were studied. No residual effects were found in learning of an eight-arm radial maze task, nor on a differential reinforcement of low-rate responding (DRL-20) task, nor on open field activity. On the other hand, two-way shuttle box avoidance learning was facilitated by previous cannabis treatment, since cannabis-treated rats exhibited shorter mean latencies to avoid footshock than vehicle controls. The findings indicate greater vulnerability of immature organisms (previous studies) than mature organisms (the present study) to long-term effects of chronic cannabis administration.

  18. Chronic exercise dampens hippocampal glutamate overflow induced by kainic acid in rats.

    PubMed

    Holmes, Philip V; Reiss, Jenny I; Murray, Patrick S; Dishman, Rod K; Spradley, Jessica M

    2015-05-01

    Our laboratory has previously reported that chronic, voluntary exercise diminishes seizure-related behaviors induced by convulsant doses of kainic acid. The present experiments tested the hypothesis that exercise exerts this protective effect through a mechanism involving suppression of glutamate release in the hippocampal formation. Following three weeks of voluntary wheel running or sedentary conditions, rats were injected with 10 mg/kg of kainic acid, and hippocampal glutamate was measured in real time using a telemetric, in vivo voltammetry system. A separate experiment measured electroencephalographic (EEG) activity following kainic acid treatment. Results of the voltammetry experiment revealed that the rise in hippocampal glutamate induced by kainic acid is attenuated in exercising rats compared to sedentary controls, indicating that the exercise-induced protection against seizures involves regulation of hippocampal glutamate release. The findings reveal the potential benefit of regular exercise in the treatment and prevention of seizure disorders and suggest a possible neurobiological mechanism underlying this effect. PMID:25668513

  19. Effects of combined exposure of F344 rats to radiation and chronically inhaled cigarette smoke

    SciTech Connect

    Finch, G.L.; Nikula, K.J.; Barr, E.B.

    1995-12-01

    Nuclear workers may be exposed to radiation in various forms, such as low-LET {gamma}-irradiation or {alpha}-irradiation from inhaled {sup 239}PuO{sub 2} particles. These workers may then have increased risk for lung cancer compared to the general population. Of additional concern is the possibility that interactions between radiation and other carcinogens may increase the risk of cancer induction, compared to the risks from either type of agent alone. An important and common lung carcinogen is cigarette smoke. The purpose of this project is to better determine the combined effects of chronically inhaled cigarette smoke and either inhaled {sup 239}PuO{sub 2} or external, thoracic X-irradiation on the induction of lung cancer in rats. Histologic and dosimetric evaluations of rats in the CS + {sup 239}PuO{sub 2} study continue, and the study of CS + X rays is beginning.

  20. Aliskiren Prevents the Toxic Effects of Peritoneal Dialysis Fluids during Chronic Dialysis in Rats

    PubMed Central

    Pérez-Martínez, Juan; Pérez-Martínez, Francisco C.; Carrión, Blanca; Masiá, Jesús; Ortega, Agustín; Simarro, Esther; Nam-Cha, Syong H.; Ceña, Valentín

    2012-01-01

    The benefits of long-term peritoneal dialysis (PD) in patients with end-stage renal failure are short-lived due to structural and functional changes in the peritoneal membrane. In this report, we provide evidence for the in vitro and in vivo participation of the renin-angiotensin-aldosterone system (RAAS) in the signaling pathway leading to peritoneal fibrosis during PD. Exposure to high-glucose PD fluids (PDFs) increases damage and fibrosis markers in both isolated rat peritoneal mesothelial cells and in the peritoneum of rats after chronic dialysis. In both cases, the addition of the RAAS inhibitor aliskiren markedly improved damage and fibrosis markers, and prevented functional modifications in the peritoneal transport, as measured by the peritoneal equilibrium test. These data suggest that inhibition of the RAAS may be a novel way to improve the efficacy of PD by preventing inflammation and fibrosis following peritoneal exposure to high-glucose PDFs. PMID:22558414

  1. Biodegradable Magnesium (Mg) Implantation Does Not Impose Related Metabolic Disorders in Rats with Chronic Renal Failure

    NASA Astrophysics Data System (ADS)

    Wang, Jiali; Xu, Jiankun; Liu, Waiching; Li, Yangde; Qin, Ling

    2016-05-01

    Mg and its alloys have been considered as one of the most promising biodegradable medical devices, but it was still unclear whether hypermagnesemia involved health risks would occur in persons with kidney disease due to their deteriorated kidney function for Mg ions excretion from their body. In this study, we established a chronic renal failure (CRF) model in rats induced by adenine administration prior to Mg implantation, aiming to predict if CRF patients are suitable for the use of Mg implants. The results showed that Mg levels in serum, urine, feces and internal organs had no significant changes after Mg implantation for both normal and CRF rats. Biochemical indices detection and histopathological analysis in kidney, liver and heart tissue confirmed that Mg implants did not induce any extra damage in animals even with renal failure. Our study indicates that Mg based orthopaedic medical device may be considered for use in CRF patients without biosafety concerns.

  2. Anemia and genotoxicity induced by sub-chronic intragastric treatment of rats with titanium dioxide nanoparticles.

    PubMed

    Grissa, Intissar; Elghoul, Jaber; Ezzi, Lobna; Chakroun, Sana; Kerkeni, Emna; Hassine, Mohsen; El Mir, Lassaad; Mehdi, Meriem; Ben Cheikh, Hassen; Haouas, Zohra

    2015-12-01

    Titanium dioxide nanoparticles (TiO2 NPs) are widely used for their whiteness and opacity. We investigated the hematological effects and genotoxicity of anatase TiO2 NPs following sub-chronic oral gavage treatment. TiO2-NPs were characterized by X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Wistar rats were treated with anatase TiO2 NPs by intragastric administration for 60 days. Hematological analysis showed a significant decrease in RBC and HCT and a significant increase in MCV, PLT, MPV and WBC at higher doses. Furthermore, abnormally shaped red cells, sometimes containing micronuclei, and hyper-segmented neutrophil nuclei were observed with TiO2 NPs treatment. The micronucleus test revealed damage to chromosomes in rat bone marrow at 100 and 200mg/kg bw; the comet assay showed significant DNA damage at the same doses.

  3. Biodegradable Magnesium (Mg) Implantation Does Not Impose Related Metabolic Disorders in Rats with Chronic Renal Failure

    PubMed Central

    Wang, Jiali; Xu, Jiankun; Liu, Waiching; Li, Yangde; Qin, Ling

    2016-01-01

    Mg and its alloys have been considered as one of the most promising biodegradable medical devices, but it was still unclear whether hypermagnesemia involved health risks would occur in persons with kidney disease due to their deteriorated kidney function for Mg ions excretion from their body. In this study, we established a chronic renal failure (CRF) model in rats induced by adenine administration prior to Mg implantation, aiming to predict if CRF patients are suitable for the use of Mg implants. The results showed that Mg levels in serum, urine, feces and internal organs had no significant changes after Mg implantation for both normal and CRF rats. Biochemical indices detection and histopathological analysis in kidney, liver and heart tissue confirmed that Mg implants did not induce any extra damage in animals even with renal failure. Our study indicates that Mg based orthopaedic medical device may be considered for use in CRF patients without biosafety concerns. PMID:27210744

  4. The effect of selective, chronic stimulation on motor unit size in developing rat muscle.

    PubMed

    Ridge, R M; Betz, W J

    1984-10-01

    One of the two peripheral nerves which innervate rat lumbrical muscle was stimulated chronically in vivo during the postnatal period of synapse elimination to determine whether the differential stimulation would affect the outcome of the elimination process. Rats were anesthetized for about 4 hr a day for 5 to 6 consecutive days, during which time the sural nerve (or, in other animals, the lateral plantar nerve) was electrically stimulated. Each animal received about 10(6) stimuli. After the last stimulation period, the sizes of motor units in both nerves were estimated from motor unit tension recorded in vitro. We found that, on average, sural motor units were larger than others in animals which had received sural nerve stimulation and smaller than others in animals which had received lateral planter nerve stimulation. These results are consistent with the hypothesis that more active nerve terminals possess a relative advantage in competing for occupancy of the endplate. PMID:6491726

  5. Adolescent and adult male spontaneous hyperactive rats (SHR) respond differently to acute and chronic methylphenidate (Ritalin).

    PubMed

    Barron, Elyssa; Yang, Pamela B; Swann, Alan C; Dafny, Nachum

    2009-01-01

    Eight groups of male adolescent and adult spontaneous hyperactive rats (SHR) were used in a dose response (saline, 0.6, 2.5, and 10 mg/kg) experiment of methylphenidate (MPD). Four different locomotor indices were recorded for 2 hours postinjection using a computerized monitoring system. Acutely, the 0.6 mg/kg dose of MPD did not elicit an increase in locomotor activity in either the adolescent or in the adult male SHR. The 2.5 and the 10.0 mg/kg doses increased activity in the adolescent and the adult rats. Chronically, MPD treatment when comparing adolescent and adult gave the following results: the 0.6 mg/kg dose of MPD failed to cause sensitization in the adolescent group but caused sensitization in the adult group, while the 2.5 and 10 mg/kg both caused sensitization in the adolescent and adult groups.

  6. Differential oxidative stress and DNA damage in rat brain regions and blood following chronic arsenic exposure.

    PubMed

    Mishra, D; Flora, S J S

    2008-05-01

    Chronic arsenic poisoning caused by contaminated drinking water is a wide spread and worldwide problem particularly in India and Bangladesh. One of the possible mechanisms suggested for arsenic toxicity is the generation of reactive oxygen species (ROS). The present study was planned 1) to evaluate if chronic exposure to arsenic leads to oxidative stress in blood and brain - parts of male Wistar rats and 2) to evaluate which brain region of the exposed animals was more sensitive to oxidative injury. Male Wistar rats were exposed to arsenic (50A ppm sodium arsenite in drinking water) for 10A months. The brain was dissected into five major parts, pons medulla, corpus striatum, cortex, hippocampus, and cerebellum. A number of biochemical variables indicative of oxidative stress were studied in blood and different brain regions. Single-strand DNA damage using comet assay was also assessed in lymphocytes. We observed a significant increase in blood and brain ROS levels accompanied by the depletion of GSH/GSSG ratio and glucose-6-phosphate dehydrogenase (G6PD) activity in different brain regions of arsenic-exposed rats. Chronic arsenic exposure also caused significant single-strand DNA damage in lymphocytes as depicted by comet with a tail in arsenic-exposed cells compared with the control cells. On the basis of results, we concluded that the cortex region of the brain was more sensitive to oxidative injury compared with the other regions studied. The present study, thus, leads us to suggest that arsenic induces differential oxidative stress in brain regions with cortex followed by hippocampus and causes single-strand DNA damage in lymphocytes.

  7. Chronic alcohol intake upregulates hepatic expression of carotenoid cleavage enzymes and PPAR in rats.

    PubMed

    Luvizotto, Renata A M; Nascimento, André F; Veeramachaneni, Sudipta; Liu, Chun; Wang, Xiang-Dong

    2010-10-01

    Excessive and chronic alcohol intake leads to a lower hepatic vitamin A status by interfering with vitamin A metabolism. Dietary provitamin A carotenoids can be converted into vitamin A mainly by carotenoid 15,15'-monooxygenase 1 (CMO1) and, to a lesser degree, carotenoid 9'10'-monooxygenase 2 (CMO2). CMO1 has been shown to be regulated by several transcription factors, such as the PPAR, retinoid X receptor, and thyroid receptor (TR). The regulation of CMO2 has yet to be identified. The impact of chronic alcohol intake on hepatic expressions of CMO1 and CMO2 and their related transcription factors are unknown. In this study, Fischer 344 rats were pair-fed either a liquid ethanol Lieber-DeCarli diet (n = 10) or a control diet (n = 10) for 11 wk. Hepatic retinoid concentration and expressions of CMO1, CMO2, PPARγ, PPARα, and TRβ as well as plasma thyroid hormones levels were analyzed. We observed that administering alcohol decreased hepatic retinoid levels but increased mRNA concentrations of CMO1, CMO2, PPARγ, PPARα, and TRβ and upregulated protein levels of CMO2, PPARγ, and PPARα. There was a positive correlation of PPARγ with CMO1 (r = 0.89; P < 0.0001) and both PPARγ and PPARα with CMO2 (r = 0.72, P < 0.001 and r = 0.62, P < 0.01, respectively). Plasma thyroid hormone concentrations did not differ between the control rats and alcohol-fed rats. This study suggests that chronic alcohol intake significantly upregulates hepatic expression of CMO1 and, to a much lesser extent, CMO2. This process may be due to alcohol-induced PPARγ expression and lower vitamin A status in the liver.

  8. Chronic iron overload in rats induces oval cells in the liver.

    PubMed Central

    Smith, P. G.; Yeoh, G. C.

    1996-01-01

    Liver damage induced by a variety of agents including hepatocarcinogens, alcohol, and virus induces proliferation of oval cells. In this study, iron overloading of the liver is used as a means of inducing liver damage over an extended period to ascertain whether it promotes the appearance of oval cells. Rats were fed a 2% carbonyl-iron-supplemented diet for 3 or 6 months. Extensive iron deposits appeared periportally in hepatocytes and some Kupffer cells. Iron deposition was less pronounced pericentrally. Small oval-like cells, morphologically and immunocytochemically similar to CDE-derived oval cells, were identified and quantified. They first emerged periportally and subsequently in small tracts or foci nearer central regions and stained positively for alpha-fetoprotein, pi-class glutathione S-transferase, and the embryonic form of pyruvate kinase. They contained very few iron deposits and were classified as iron free. The major difference between CDE- and iron-overload-derived oval cells was that the latter were negative for transferrin. This study shows that cellular changes occurring in iron-overloaded rat liver are similar to those observed in rats placed on a hepatocarcinogenic diet and in rats chronically exposed to alcohol. Images Figure 1 Figure 2 Figure 3 PMID:8701979

  9. Suppressing cardiac vagal modulation and changing sleep patterns in rats after chronic ischemic stroke injury.

    PubMed

    Huang, Shiang-Suo; Su, Hsing-Hui; Kuo, Terry B J; Chen, Chun-Yu; Lan, Yi-Yun; Liu, Bi-Yu; Yang, Ding-I; Tsai, Shih-Chih; Yang, Cheryl C H

    2012-08-16

    Chronic autonomic function and sleep architecture changes in patients post-stroke are not well understood. Using wireless polysomnographic recordings, this study aimed to investigate the long-term effects on sleep patterns and autonomic function in free moving rats after middle cerebral artery occlusion (MCAO). The sleep pattern and heart rate variability (HRV) of Wistar-Kyoto rats (WKY) were analyzed. After 7-10days, the rats were divided into two groups: an MCAO group (n=8) and a sham surgery group (n=8). Compared with shams, MCAO rats showed decreased accumulated quiet sleep (QS) time over 24h during the 3rd week. The time percentage, duration and delta power of QS were also significantly decreased in the MCAO group during the dark period. Compared with baseline, there were significant increases in the parasympathetic-associated HRV measures in the sham group, including the total power (TP), high frequency power (HF) and lower frequency power (LF), throughout the post-operative weeks (primarily the 2nd and 3rd weeks), reflecting a developmental increase of parasympathetic modulation; the normalized LF and the LF-HF ratio were unaffected. In great contrast, however, most of the HRV measures in the MCAO group were not significantly changed. Therefore, this study showed that the long-term effects of ischemic stroke injury involve retardation of the establishment of parasympathetic enhancement and disturbance of the normal sleep-wake cycle. PMID:22727146

  10. Metabolic consequences of chronic sleep restriction in rats: changes in body weight regulation and energy expenditure.

    PubMed

    Barf, R P; Van Dijk, G; Scheurink, A J W; Hoffmann, K; Novati, A; Hulshof, H J; Fuchs, E; Meerlo, P

    2012-10-10

    Epidemiological studies have shown an association between short or disrupted sleep and an increased risk to develop obesity. In animal studies, however, sleep restriction leads to an attenuation of weight gain that cannot be explained by changes in energy intake. In the present study, we assessed whether the attenuated weight gain under conditions of restricted sleep is a consequence of an overall increase in energy expenditure. Adult male rats were subjected to a schedule of chronic sleep restriction (SR) for 8 days with a 4h window of unrestricted rest per day. Electroencephalogram and electromyogram recordings were performed to quantify the effect of the sleep restriction schedule on sleep-wake patterns. In a separate experiment, we measured sleep restriction-induced changes in body weight, food intake, and regulatory hormones such as glucose, insulin, leptin and corticosterone. To investigate whether a change in energy expenditure underlies the attenuation of weight gain, energy expenditure was measured by the doubly labeled water method from day 5 until day 8 of the SR protocol. Results show a clear attenuation of weight gain during sleep restriction but no change in food intake. Baseline plasma glucose, insulin and leptin levels are decreased after sleep restriction which presumably reflects the nutritional status of the rats. The daily energy expenditure during SR was significantly increased compared to control rats. Together, we conclude that the attenuation of body weight gain in sleep restricted rats is explained by an overall increase in energy expenditure together with an unaltered energy intake. PMID:22995976

  11. The Effect of Pulsed Radiofrequency Applied to the Peripheral Nerve in Chronic Constriction Injury Rat Model

    PubMed Central

    Lee, Jun-Beom; Byun, Jeong-Hyun; Kim, Young; Lee, Ji Shin

    2015-01-01

    Objective To investigate the effect of pulsed radiofrequency (PRF) applied proximal to the injured peripheral nerve on the expression of tumor necrosis factor-α (TNF-α) in a neuropathic pain rat model. Methods Nineteen male Sprague-Dawley rats were used in the study. All rats underwent chronic constriction injury (CCI) procedure. After 7 days of CCI, withdrawal frequency of affected hind paw to mechanical stimuli and withdrawal latency of affected hind paw to heat stimulus were measured. They were randomly divided into two groups: group A, CCI group (n=9) and group B, CCI treated with PRF group (n=10). Rats of group B underwent PRF procedure on the sciatic nerve. Withdrawal frequency and withdrawal latency were measured at 12 hours, and 7 days after PRF. Immunohistochemistry and Western blot analysis were performed using a TNF-α antibody. Results Before PRF, withdrawal frequency and withdrawal latency were not different in both groups. After PRF, withdrawal frequency decreased and withdrawal latency prolonged over time in group B. There was significant interaction between time and group for each withdrawal frequency and withdrawal latency. Group B showed decreased TNF-α immunoreactivity of the spinal cord and sciatic nerve at 7 days. Conclusion PRF applied proximal to the peripheral nerve injury is potentially helpful for the reduction of neuropathic pain by neuromodulation of inflammatory markers. PMID:26605164

  12. l-Carnitine improves cognitive and renal functions in a rat model of chronic kidney disease.

    PubMed

    Abu Ahmad, Nur; Armaly, Zaher; Berman, Sylvia; Jabour, Adel; Aga-Mizrachi, Shlomit; Mosenego-Ornan, Efrat; Avital, Avi

    2016-10-01

    Over the past decade, the prevalence of chronic kidney disease (CKD) has reached epidemic proportions. The search for novel pharmacological treatment for CKD has become an area of intensive clinical research. l-Carnitine, considered as the "gatekeeper" responsible for admitting long chain fatty acids into cell mitochondria. l-Carnitine synthesis and turnover are regulated mainly by the kidney and its levels inversely correlate with serum creatinine of normal subjects and CKD patients. Previous studies showed that l-carnitine administration to elderly people is improving and preserving cognitive function. As yet, there are no clinical intervention studies that investigated the effect of l-carnitine administration on cognitive impairment evidenced in CKD patients. Thus, we aimed to investigate the effects of l-carnitine treatment on renal function and on the cognitive performance in a rat model of progressive CKD. To assess the role of l-carnitine on CKD condition, we estimated the renal function and cognitive abilities in a CKD rat model. We found that all CKD animals exhibited renal function deterioration, as indicated by elevated serum creatinine, BUN, and ample histopathological abnormalities. l-Carnitine treatment of CKD rats significantly reduced serum creatinine and BUN, attenuated renal hypertrophy and decreased renal tissue damage. In addition, in the two way shuttle avoidance learning, CKD animals showed cognitive impairment which recovered by the administration of l-carnitine. We conclude that in a rat model of CKD, l-carnitine administration significantly improved cognitive and renal functions.

  13. Chronic Fluoride Toxicity and Myocardial Damage: Antioxidant Offered Protection in Second Generation Rats

    PubMed Central

    Basha, Mahaboob P.; Sujitha, N. S.

    2011-01-01

    This experiment was designed to investigate the extent of peroxidative changes and histological alterations in the myocardium of rats exposed to high fluoride for two generations, in addition to ameliorative role of selenium and vitamin E on the above indices. Adult albino Wistar rats were given fluoride through drinking water (200 ppm F) and maintained subsequently for two generations, while they were exposed to fluoride throughout the experiment. Fluoride treatment significantly increased the lipid peroxidation and decreased the activity of antioxidant enzymes, viz., catalase, superoxide dismutase, and glutathione level in auricle and ventricle regions of the heart. Decreased feed and water consumption, organ somatic index and marginal drop in body growth rate were observed. Decreased antioxidant enzymes and increased malondialdehyde levels might be related to oxidative damage that occurs variably in the myocardium of rats. Biochemical changes were supported by the histological observations, which also revealed that chronic exposure to fluoride causes damage to the myocardium. Results of this study can be taken as an index of cardio-toxicity in rats exposed to water fluoridation. Further, oral supplementation of selenium and vitamin E not only inhibited oxidative stress but also enhanced the activities of antioxidant enzymes. Administration of antioxidants during fluoride exposure significantly overcame cardiac fluoride toxicity and therefore may be a therapeutic strategy for fluorotic victims. PMID:21976813

  14. Protective effects of chronic mild stress during adolescence in the low-novelty responder rat.

    PubMed

    Rana, Samir; Nam, Hyungwoo; Glover, Matthew E; Akil, Huda; Watson, Stanley J; Clinton, Sarah M; Kerman, Ilan A

    2016-01-01

    Stress-elicited behavioral and physiologic responses vary widely across individuals and depend on a combination of environmental and genetic factors. Adolescence is an important developmental period when neural circuits that guide emotional behavior and stress reactivity are still maturing. A critical question is whether stress exposure elicits contrasting effects when it occurs during adolescence versus adulthood. We previously found that Sprague-Dawley rats selectively bred for low-behavioral response to novelty (bred Low Responders; bLRs) are particularly sensitive to chronic unpredictable mild stress (CMS) exposure in adulthood, which exacerbates their typically high levels of spontaneous depressive- and anxiety-like behavior. Given developmental processes known to occur during adolescence, we sought to determine whether the impact of CMS on bLR rats is equivalent when they are exposed to it during adolescence as compared with adulthood. Young bLR rats were either exposed to CMS or control condition from postnatal days 35-60. As adults, we found that CMS-exposed bLRs maintained high levels of sucrose preference and exhibited increased social exploration along with decreased immobility on the forced swim test compared with bLR controls. These data indicate a protective effect of CMS exposure during adolescence in bLR rats.

  15. Protective Effects of Chronic Mild Stress during Adolescence in the Low Novelty Responder Rat

    PubMed Central

    Rana, Samir; Nam, Hyungwoo; Glover, Matthew E.; Akil, Huda; Watson, Stanley J.; M.Clinton, Sarah; Kerman, Ilan A.

    2016-01-01

    Stress-elicited behavioral and physiologic responses vary widely across individuals and depend on a combination of environmental and genetic factors. Adolescence is an important developmental period when neural circuits that guide emotional behavior and stress reactivity are still maturing. A critical question is whether stress exposure elicits contrasting effects when it occurs during adolescence versus adulthood. We previously found that Sprague Dawley rats selectively-bred for low behavioral response to novelty (bred Low Responders; bLRs) are particularly sensitive to chronic unpredictable mild stress (CMS) exposure in adulthood, which exacerbates their typically high levels of spontaneous depressive- and anxiety- like behavior. Given developmental processes known to occur during adolescence, we sought to determine whether the impact of CMS on bLR rats is equivalent when they are exposed to it during adolescence as compared to adulthood. Young bLR rats were either exposed to CMS or control condition from postnatal day 35-60. As adults we found that CMS-exposed bLRs maintained high levels of sucrose preference and exhibited increased social exploration along with decreased immobility on the forced swim test compared to bLR controls. These data indicate a protective effect of CMS exposure during adolescence in bLR rats. PMID:26473581

  16. Naloxone excites oxytocin neurones in the supraoptic nucleus of lactating rats after chronic morphine treatment.

    PubMed Central

    Bicknell, R J; Leng, G; Lincoln, D W; Russell, J A

    1988-01-01

    1. Lactating rats were implanted with a cannula in a lateral cerebral ventricle to deliver morphine (up to 50 micrograms/h) chronically from a subcutaneous osmotically driven mini-pump. After infusion of morphine for 5 days the rats were anaesthetized with urethane and prepared with ventral surgery for recording the electrical activity of single, antidromically identified neurones in the supraoptic nucleus. 2. A single I.V. injection of naloxone (5 mg/kg) in these rats provoked a long-lasting, large increase in intramammary pressure, but in control rats had negligible effects. Concentrations in plasma of oxytocin, measured by radioimmunoassay in samples of femoral arterial blood, rose from 44.7 +/- 2.5 to 1072.1 +/- 89.5 pg/ml (means +/- S.E.M.) 6 min after naloxone in the morphine-treated rats. In control rats, the concentration of oxytocin in plasma rose only from 42.1 +/- 2.9 to 125.1 +/- 28.2 pg/ml after naloxone. 3. Naloxone produced a transient increase in arterial blood pressure in morphine-treated but not control rats. Concentrations in plasma of vasopressin, measured by radioimmunoassay in samples of femoral arterial blood, rose in morphine-treated rats from 7.4 +/- 2.4 to 29.2 +/- 3.7 pg/ml after naloxone, but did not rise significantly in control rats. 4. Naloxone (1-5 mg/kg) produced a prompt and prolonged increase in the discharge rate of each of ten continuously active (putative oxytocin) cells recorded from ten morphine-treated rats. The discharge rate of the six cells tested at the highest dose (5 mg/kg) increased by an average of 6.3 Hz (360%) within 5 min, and the firing rate remained elevated for at least 30 min; the discharge rate of six continuously active supraoptic neurones recorded in control rats was not affected by naloxone. 5. The firing activity of five phasic (putative vasopressin) supraoptic neurones in morphine-treated rats was increased for at least 30 min by the injection of naloxone; these increases were the result of a raised

  17. Chronic osmotic stimulation reduces vasopressin but not synaptophysin content in rat neurohypophysis.

    PubMed

    Ehrhart-Bornstein, M; Thorn, N A; Treiman, M

    1990-10-30

    The content of synaptophysin, a vesicular integral membrane protein of neurons and endocrine cells, and that of vasopressin was measured in neurohypophyses of rats during chronic osmotic stimulation. The animals received 2% NaCl in their drinking water for up to 4 days. Synaptophysin content of neurohypophyses was determined using quantitative immunoblotting, vasopressin content was measured by radioimmunoassay. Salt loading caused a decrease in the content of vasopressin to about 15% of that of control animals, whether expressed per neurohypophysis or relative to the total tissue protein. In contrast, no change was found in the synaptophysin content. Taken together with published evidence of changes in the relative numbers of the hormone-containing neurosecretory granules (NSGs) and the microvesicles (MVs) under the conditions of chronic osmotic stimulation, these results strongly indicate the surface density of synaptophysin on NSGs to be significantly lower than its surface density on MVs. PMID:2129060

  18. Beneficial effect of testosterone in the treatment of chronic autoimmune thyroiditis in rats

    SciTech Connect

    Ahmed, S.A.; Young, P.R.; Penhale, W.J.

    1986-01-01

    Early thymectomy and sublethal irradiation of normal rats consistently induces a sex-dependent chronic autoimmune thyroiditis. Females are much more susceptible to this autoimmune disorder than are males. The possible therapeutic effects of testosterone (Te) on established autoimmune thyroiditis has been investigated in this model. The pathologic condition of the gland before treatment was monitored by a thyroid grafting and extirpation techniques. Te administration by either parenteral injection or implantation caused significant regression of established thyroiditis. Repeated doses of Te ester in oil were found to be more effective than powdered free-Te given by implantation, and frequently produced complete resolution of chronic lesions involving the entire gland. In these thyroids, there was reappearance of normal thyroid architecture and complete absence of mononuclear cellular infiltration. However, no inhibitory effect on serum autoantibody production to thyroglobulin was noted with any form of Te treatment. These observations strengthen the concept that cellular rather than humoral mechanisms are involved in the pathogenesis of thyroiditis.

  19. Acceleration of vertical migration of corneal epithelial cells in albino rats during chronic immobilization stress

    SciTech Connect

    Timoshin, S.S.; Berezhnova, N.I.

    1986-01-01

    This paper studies the effect of chronic immobilization stress on the kinetics of corneal epithelial cells from the basal layer into higher layers. Experiments were carried out on 49 male rats. The animals were given an intraperitoneal injection of tritium-thymidine and an additional application of 5 microCi of tritium-thymidine was made to its surface because the cornea has no blood supply. The animals were killed and the cornea removed for investigation. Values of the index of labeled nuclei and intensity of thymidine labeling, characterizing DNA synthesis in the corneas of the control and experimental animals showed no significant change compared with their values in a pervious series of experiments. Chronic exposure to stress increased the velocity of vertical migration of the cells from the basal layer toward the outer layers of the cornea.

  20. Effects of Anterior Thalamic Nucleus Deep Brain Stimulation in Chronic Epileptic Rats

    PubMed Central

    Amorim, Beatriz; Cavarsan, Clarissa; Miranda, Maisa Ferreira; Aarão, Mayra C.; Madureira, Ana Paula; Rodrigues, Antônio M.; Nobrega, José N.; Mello, Luiz E.; Hamani, Clement

    2014-01-01

    Deep brain stimulation (DBS) has been investigated for the treatment of epilepsy. In rodents, an increase in the latency for the development of seizures and status epilepticus (SE) has been reported in different animal models but the consequences of delivering stimulation to chronic epileptic animals have not been extensively addressed. We study the effects of anterior thalamic nucleus (AN) stimulation at different current intensities in rats rendered epileptic following pilocarpine (Pilo) administration. Four months after Pilo-induced SE, chronic epileptic rats were bilaterally implanted with AN electrodes or had sham-surgery. Stimulation was delivered for 6 h/day, 5 days/week at 130 Hz, 90 µsec. and either 100 µA or 500 µA. The frequency of spontaneous recurrent seizures in animals receiving stimulation was compared to that recorded in the preoperative period and in rats given sham treatment. To investigate the effects of DBS on hippocampal excitability, brain slices from animals receiving AN DBS or sham surgery were studied with electrophysiology. We found that rats treated with AN DBS at 100 µA had a 52% non-significant reduction in the frequency of seizures as compared to sham-treated controls and 61% less seizures than at baseline. Animals given DBS at 500 µA had 5.1 times more seizures than controls and a 2.8 fold increase in seizure rate as compared to preoperative values. In non-stimulated controls, the average frequency of seizures before and after surgery remained unaltered. In vitro recordings have shown that slices from animals previously given DBS at 100 µA had a longer latency for the development of epileptiform activity, shorter and smaller DC shifts, and a smaller spike amplitude compared to non-stimulated controls. In contrast, a higher spike amplitude was recorded in slices from animals given AN DBS at 500 µA. PMID:24892420

  1. Chronic At- and Below-Level Pain after Moderate Unilateral Cervical Spinal Cord Contusion in Rats

    PubMed Central

    Wade, Rodel E.; Houlé, John D.

    2013-01-01

    Abstract Chronic neuropathic pain is a significant consequence of spinal cord injury (SCI) that is associated with evoked pain, including allodynia and/or hyperalgesia. Allodynia is defined as a painful response to normally innocuous stimuli, and hyperalgesia occurs when there is an amplified pain response to normally noxious stimuli. We describe a model of a unilateral cervical level (C5) contusion injury where sensory recovery was assessed weekly for 6 weeks in 32 adult, female, Sprague-Dawley rats. Bilateral thermal hyperalgesia and tactile allodynia are detectable in the fore- and hindpaws as early as 7 days post-injury (dpi) and persist for at least 42 days. Paw withdrawal latency in response to a noxious thermal stimulus significantly intra-animal pre-operative values. Change in paw withdrawal latency plateaued at 21 dpi. Interestingly, bilateral forepaw allodynia develops in fewer than 40% of rats as measured by von Frey monofilament testing. Similar results occur in the hindpaws, where bilateral allodynia occurs in 46% of rats with SCI. The contralesional forepaw and both hindpaws of rats showed a slight increase in paw withdrawal threshold to tactile stimuli acutely after SCI, corresponding to ipsilesional forelimb motor deficits that resolve over time. That there is no difference among allodynic and non-allodynic groups in overall spared tissue or specifically of the dorsal column or ventrolateral white matter where ascending sensory tracts reside suggests that SCI-induced pain does not depend solely on the size or extent of the lesion, but that other mechanisms are in play. These observations provide a valid model system for future testing of therapeutic interventions to prevent the onset or to reduce the debilitating effects of chronic neuropathic pain after SCI. PMID:23216008

  2. Chronic Voluntary Ethanol Consumption Induces Favorable Ceramide Profiles in Selectively Bred Alcohol-Preferring (P) Rats

    PubMed Central

    Godfrey, Jessica; Jeanguenin, Lisa; Castro, Norma; Olney, Jeffrey J.; Dudley, Jason; Pipkin, Joseph; Walls, Stanley M.; Wang, Wei; Herr, Deron R.; Harris, Greg L.; Brasser, Susan M.

    2015-01-01

    Heavy alcohol consumption has detrimental neurologic effects, inducing widespread neuronal loss in both fetuses and adults. One proposed mechanism of ethanol-induced cell loss with sufficient exposure is an elevation in concentrations of bioactive lipids that mediate apoptosis, including the membrane sphingolipid metabolites ceramide and sphingosine. While these naturally-occurring lipids serve as important modulators of normal neuronal development, elevated levels resulting from various extracellular insults have been implicated in pathological apoptosis of neurons and oligodendrocytes in several neuroinflammatory and neurodegenerative disorders. Prior work has shown that acute administration of ethanol to developing mice increases levels of ceramide in multiple brain regions, hypothesized to be a mediator of fetal alcohol-induced neuronal loss. Elevated ceramide levels have also been implicated in ethanol-mediated neurodegeneration in adult animals and humans. Here, we determined the effect of chronic voluntary ethanol consumption on lipid profiles in brain and peripheral tissues from adult alcohol-preferring (P) rats to further examine alterations in lipid composition as a potential contributor to ethanol-induced cellular damage. P rats were exposed for 13 weeks to a 20% ethanol intermittent-access drinking paradigm (45 ethanol sessions total) or were given access only to water (control). Following the final session, tissues were collected for subsequent chromatographic analysis of lipid content and enzymatic gene expression. Contrary to expectations, ethanol-exposed rats displayed substantial reductions in concentrations of ceramides in forebrain and heart relative to non-exposed controls, and modest but significant decreases in liver cholesterol. qRT-PCR analysis showed a reduction in the expression of sphingolipid delta(4)-desaturase (Degs2), an enzyme involved in de novo ceramide synthesis. These findings indicate that ethanol intake levels achieved by

  3. Pneumoconiosis in rats exposed chronically to oil shale dust and diesel exhaust, alone and in combination

    SciTech Connect

    Mauderly, J.L.; Barr, E.B.; Eidson, A.F.; Harkema, J.R.; Henderson, R.F.; Pickrell, J.A.; Wolff, R.K.

    1991-01-01

    Rats were exposed by chronic inhalation to diesel exhaust or oil shale dust, alone and in combination to examine pathophysiologic interactions between the dusts. The three agents all accumulated progressively in lungs and caused similar pneumoconiotic responses. The effects of combined exposures tended to be greater than additive. The magnitude of effects was more closely correlated to particle lung burden than to exposure concentration. This suggests that effects of prolonged human exposures to combined dust atmospheres may be estimated better on the basis of predicted lung burden than exposure concentration. 14 refs., 2 figs., 2 tabs.

  4. 18F-DPA-714 PET Imaging for Detecting Neuroinflammation in Rats with Chronic Hepatic Encephalopathy

    PubMed Central

    Kong, Xiang; Luo, Song; Wu, Jin Rong; Wu, Shawn; De Cecco, Carlo N.; Schoepf, U. Joseph; Spandorfer, Adam J.; Wang, Chun Yan; Tian, Ying; Chen, Hui Juan; Lu, Guang Ming; Yang, Gui Fen; Zhang, Long Jiang

    2016-01-01

    Neuroinflammation is considered to be the pathogenesis of hepatic encephalopathy (HE), and imaging neuroinflammation is implicated in HE management. 11C-PK11195, a typical translocator protein (TSPO) radiotracer, is used for imaging neuroinflammation. However, it has inherent limitations, such as short half-life and limited availability. The purpose of this study was to demonstrate the efficiency of new generation TSPO radiotracer, 18F-DPA-714, in detecting and monitoring neuroinflammation of chronic HE. This study was divided into two parts. The first part compared 18F-DPA-714 and 11C-PK11195 radiotracers in ten HE induced rats [bile duct ligation (BDL) and fed hyperammonemic diet (HD)] and 6 control rats. The animal subjects underwent dynamic positron emission tomography (PET) during 2-day intervals. The 11C-PK11195 PET study showed no differences in whole brain average percent injected dose per gram (%ID/g) values at all time points (all P>0.05), while the 18F-DPA-714 PET study showed higher whole brain average %ID/g values in HE rats compared to control group rats at 900 s to 3300 s after injecting radiotracer (all P<0.05). The second part of the study evaluated the effectiveness of ibuprofen (IBU) treatment to chronic HE. Forty rats were classified into six groups, including Sham+normal saline (NS), Sham+IBU, BDL+NS, BDL+HD+NS, BDL+IBU, and BDL+HD+IBU groups. 18F-DPA-714 PET was used to image neuroinflammation. Whole and regional brain average %ID/g values, neurological features, inflammatory factors and activated microglia showed better in the IBU groups than in the NS groups (all P<0.05) and no difference was seen in the Sham groups compared to IBU groups (all P>0.05). In conclusion, this study demonstrated that 18F-DPA-714 is an ideal TPSO radiotracer for imaging neuroinflammation and monitoring anti-neuroinflammation treatment efficacy of chronic HE. PMID:27279913

  5. Vortioxetine restores reversal learning impaired by 5-HT depletion or chronic intermittent cold stress in rats.

    PubMed

    Wallace, Ashley; Pehrson, Alan L; Sánchez, Connie; Morilak, David A

    2014-10-01

    Current treatments for depression, including serotonin-specific reuptake inhibitors (SSRIs), are only partially effective, with a high incidence of residual symptoms, relapse, and treatment resistance. Loss of cognitive flexibility, a component of depression, is associated with dysregulation of the prefrontal cortex. Reversal learning, a form of cognitive flexibility, is impaired by chronic stress, a risk factor for depression, and the stress-induced impairment in reversal learning is sensitive to chronic SSRI treatment, and is mimicked by serotonin (5-HT) depletion. Vortioxetine, a novel, multimodal-acting antidepressant, is a 5-HT3, 5-HT7 and 5-HT1D receptor antagonist, a 5-HT1B receptor partial agonist, a 5-HT1A receptor agonist, and inhibits the 5-HT transporter. Using adult male rats, we first investigated the direct effects of vortioxetine, acting at post-synaptic 5-HT receptors, on reversal learning that was compromised by 5-HT depletion using 4-chloro-DL-phenylalanine methyl ester hydrochloride (PCPA), effectively eliminating any contribution of 5-HT reuptake blockade. PCPA induced a reversal learning impairment that was alleviated by acute or sub-chronic vortioxetine administration, suggesting that post-synaptic 5-HT receptor activation contributes to the effects of vortioxetine. We then investigated the effects of chronic dietary administration of vortioxetine on reversal learning that had been compromised in intact animals exposed to chronic intermittent cold (CIC) stress, to assess vortioxetine's total pharmacological effect. CIC stress impaired reversal learning, and chronic vortioxetine administration prevented the reversal-learning deficit. Together, these results suggest that the direct effect of vortioxetine at 5-HT receptors may contribute to positive effects on cognitive flexibility deficits, and may enhance the effect of 5-HT reuptake blockade.

  6. Chronic coffee and caffeine ingestion effects on the cognitive function and antioxidant system of rat brains.

    PubMed

    Abreu, Renata Viana; Silva-Oliveira, Eliane Moretto; Moraes, Márcio Flávio Dutra; Pereira, Grace Schenatto; Moraes-Santos, Tasso

    2011-10-01

    Coffee is a popular beverage consumed worldwide and its effect on health protection has been well studied throughout literature. This study investigates the effect of chronic coffee and caffeine ingestion on cognitive behavior and the antioxidant system of rat brains. The paradigms of open field and object recognition were used to assess locomotor and exploratory activities, as well as learning and memory. The antioxidant system was evaluated by determining the activities of glutathione reductase (GR), glutathione peroxidase (GPx) and superoxide dismutase (SOD), as well as the lipid peroxidation and reduced glutathione content. Five groups of male rats were fed for approximately 80 days with different diets: control diet (CD), fed a control diet; 3% coffee diet (3%Co) and 6% coffee diet (6%Co), both fed a diet containing brewed coffee; 0.04% caffeine diet (0.04%Ca) and 0.08% caffeine diet (0.08%Ca), both fed a control diet supplemented with caffeine. The estimated caffeine intake was approximately 20 and 40 mg/kg per day, for the 3%Co-0.04%Ca and 6%Co-0.08%Ca treatments, respectively. At 90 days of life, the animals were subjected to the behavioral tasks and then sacrificed. The results indicated that the intake of coffee, similar to caffeine, improved long-term memory when tested with object recognition; however, this was not accompanied by an increase in locomotor and exploratory activities. In addition, chronic coffee and caffeine ingestion reduced the lipid peroxidation of brain membranes and increased the concentration of reduced-glutathione. The activities of the GR and SOD were similarly increased, but no change in GPx activity could be observed. Thus, besides improving cognitive function, our data show that chronic coffee consumption modulates the endogenous antioxidant system in the brain. Therefore, chronic coffee ingestion, through the protection of the antioxidant system, may play an important role in preventing age-associated decline in the cognitive

  7. Antioxidant Effect of Spirulina (Arthrospira) maxima on Chronic Inflammation Induced by Freund's Complete Adjuvant in Rats.

    PubMed

    Gutiérrez-Rebolledo, Gabriel Alfonso; Galar-Martínez, Marcela; García-Rodríguez, Rosa Virginia; Chamorro-Cevallos, Germán A; Hernández-Reyes, Ana Gabriela; Martínez-Galero, Elizdath

    2015-08-01

    One of the major mechanisms in the pathogenesis of chronic inflammation is the excessive production of reactive oxygen and reactive nitrogen species, and therefore, oxidative stress. Spirulina (Arthrospira) maxima has marked antioxidant activity in vivo and in vitro, as well as anti-inflammatory activity in certain experimental models, the latter activity being mediated probably by the antioxidant activity of this cyanobacterium. In the present study, chronic inflammation was induced through injection of Freund's complete adjuvant (CFA) in rats treated daily with Spirulina (Arthrospira) maxima for 2 weeks beginning on day 14. Joint diameter, body temperature, and motor capacity were assessed each week. On days 0 and 28, total and differential leukocyte counts and serum oxidative damage were determined, the latter by assessing lipid peroxidation and protein carbonyl content. At the end of the study, oxidative damage to joints was likewise evaluated. Results show that S. maxima favors increased mobility, as well as body temperature regulation, and a number of circulating leukocytes, lymphocytes, and monocytes in specimens with CFA-induced chronic inflammation and also protects against oxidative damage in joint tissue as well as serum. In conclusion, the protection afforded by S. maxima against development of chronic inflammation is due to its antioxidant activity. PMID:25599112

  8. Karwinskia humboldtiana (buckthorn) fruit causes central nervous system damage during chronic intoxication in the rat.

    PubMed

    Becerra-Verdin, Eduardo M; Bermúdez-Barba, M V; Salazar-Leal, Martha E; Ancer Rodríguez, J; Romero-Diaz, Víktor; Soto-Domínguez, Adolfo; Ballesteros-Eliozondo, Raquel G; Saucedo-Cardenas, Odila; Piñeyro Lopez, Alfredo; Sepúlveda-Saavedra, Julio

    2009-05-01

    Karwinskia humboldtiana fruit (Kh) causes a neurological disorder 3-4 weeks after ingestion, characterized by flaccid, symmetrical, ascending paralysis, similar to the Guillain-Barre syndrome. In this polyneuropathy the lesion (demyelization) in peripheral nerves has been described in several animal species, both in acute and in chronic intoxication. However, no reports exist about the presence of lesions in the Central Nervous System (CNS), in chronic intoxication. We considered it important to evaluate, with histological techniques, the possible presence of lesions in the brain, by using a model of chronic intoxication that reproduces the same stages present in the human intoxication, to better understanding of this pathological process. In our present work we fed the ground Kh fruit to Wistar rats and samples of brain, cerebellum, and pons were embedded in paraffin. Sections were stained with Hematoxylin & Eosin (HE) and special stains for nerve tissue. Histopathological changes were evaluated in the CNS through the different stages of the polyneuropathy and comparison to a control group. With this methodology, we found lesions in the motor pathway. This is the first report about the presence of neuronal damage caused by Kh in the Central Nervous System in chronic intoxication.

  9. Ameliorative potential of Ocimum sanctum in chronic constriction injury-induced neuropathic pain in rats.

    PubMed

    Kaur, Gurpreet; Bali, Anjana; Singh, Nirmal; Jaggi, Amteshwar S

    2015-03-01

    The present study was designed to investigate the ameliorative potential of Ocimum sanctum and its saponin rich fraction in chronic constriction injury-induced neuropathic pain in rats. The chronic constriction injury was induced by placing four loose ligatures around the sciatic nerve, proximal to its trifurcation. The mechanical hyperalgesia, cold allodynia, paw heat hyperalgesia and cold tail hyperalgesia were assessed by performing the pinprick, acetone, hot plate and cold tail immersion tests, respectively. Biochemically, the tissue thio-barbituric acid reactive species, super-oxide anion content (markers of oxidative stress) and total calcium levels were measured. Chronic constriction injury was associated with the development of mechanical hyperalgesia, cold allodynia, heat and cold hyperalgesia along with an increase in oxidative stress and calcium levels. However, administration of Ocimum sanctum (100 and 200 mg/kg p.o.) and its saponin rich fraction (100 and 200 mg/kg p.o.) for 14 days significantly attenuated chronic constriction injury-induced neuropathic pain as well as decrease the oxidative stress and calcium levels. It may be concluded that saponin rich fraction of Ocimum sanctum has ameliorative potential in attenuating painful neuropathic state, which may be attributed to a decrease in oxidative stress and calcium levels. PMID:25673470

  10. Antioxidant Effect of Spirulina (Arthrospira) maxima on Chronic Inflammation Induced by Freund's Complete Adjuvant in Rats

    PubMed Central

    Gutiérrez-Rebolledo, Gabriel Alfonso; Galar-Martínez, Marcela; García-Rodríguez, Rosa Virginia; Chamorro-Cevallos, Germán A.; Hernández-Reyes, Ana Gabriela

    2015-01-01

    Abstract One of the major mechanisms in the pathogenesis of chronic inflammation is the excessive production of reactive oxygen and reactive nitrogen species, and therefore, oxidative stress. Spirulina (Arthrospira) maxima has marked antioxidant activity in vivo and in vitro, as well as anti-inflammatory activity in certain experimental models, the latter activity being mediated probably by the antioxidant activity of this cyanobacterium. In the present study, chronic inflammation was induced through injection of Freund's complete adjuvant (CFA) in rats treated daily with Spirulina (Arthrospira) maxima for 2 weeks beginning on day 14. Joint diameter, body temperature, and motor capacity were assessed each week. On days 0 and 28, total and differential leukocyte counts and serum oxidative damage were determined, the latter by assessing lipid peroxidation and protein carbonyl content. At the end of the study, oxidative damage to joints was likewise evaluated. Results show that S. maxima favors increased mobility, as well as body temperature regulation, and a number of circulating leukocytes, lymphocytes, and monocytes in specimens with CFA-induced chronic inflammation and also protects against oxidative damage in joint tissue as well as serum. In conclusion, the protection afforded by S. maxima against development of chronic inflammation is due to its antioxidant activity. PMID:25599112

  11. Antioxidant Effect of Spirulina (Arthrospira) maxima on Chronic Inflammation Induced by Freund's Complete Adjuvant in Rats.

    PubMed

    Gutiérrez-Rebolledo, Gabriel Alfonso; Galar-Martínez, Marcela; García-Rodríguez, Rosa Virginia; Chamorro-Cevallos, Germán A; Hernández-Reyes, Ana Gabriela; Martínez-Galero, Elizdath

    2015-08-01

    One of the major mechanisms in the pathogenesis of chronic inflammation is the excessive production of reactive oxygen and reactive nitrogen species, and therefore, oxidative stress. Spirulina (Arthrospira) maxima has marked antioxidant activity in vivo and in vitro, as well as anti-inflammatory activity in certain experimental models, the latter activity being mediated probably by the antioxidant activity of this cyanobacterium. In the present study, chronic inflammation was induced through injection of Freund's complete adjuvant (CFA) in rats treated daily with Spirulina (Arthrospira) maxima for 2 weeks beginning on day 14. Joint diameter, body temperature, and motor capacity were assessed each week. On days 0 and 28, total and differential leukocyte counts and serum oxidative damage were determined, the latter by assessing lipid peroxidation and protein carbonyl content. At the end of the study, oxidative damage to joints was likewise evaluated. Results show that S. maxima favors increased mobility, as well as body temperature regulation, and a number of circulating leukocytes, lymphocytes, and monocytes in specimens with CFA-induced chronic inflammation and also protects against oxidative damage in joint tissue as well as serum. In conclusion, the protection afforded by S. maxima against development of chronic inflammation is due to its antioxidant activity.

  12. Chronic stress effects in contralateral medial pterygoid muscle of rats with occlusion alteration.

    PubMed

    Loyola, Bruno Melo; Nascimento, Glauce Crivelaro; Fernández, Rodrigo Alberto Restrepo; Iyomasa, Daniela Mizusaki; Pereira, Yamba Carla Lara; Leite-Panissi, Christie Ramos Andrade; Issa, João Paulo Mardegan; Iyomasa, Mamie Mizusaki

    2016-10-01

    Temporomandibular disorder (TMD) has a high prevalence in our society, characterized by a severe pain condition of the masticatory muscles and temporomandibular joint. Despite the indication of multiple factor initiators of TMD, there is still controversy about its etiology and its pathophysiology is poorly understood. Using rats as experimental animals we investigated the effect of unpredictable chronic stress with or without unilateral molar extraction on the contralateral medial pterygoid muscle. Our hypothesis is that these two factors induce changes in morphology, oxidative metabolism and oxidative stress of muscle fibers. Young adult male Wistar rats (±200g) were divided into four groups: a group with extraction and unpredictable chronic stress (E+US); with extraction and without stress (E+C); without extraction and with unpredictable chronic stress (NO+US); and a control group without either extraction or stress (NO+C). The animals were subjected to unilateral extraction of the upper left molars, under intraperitoneal anesthesia with 4% Xylazine (10mg/kg) and 10% Ketamine (80mg/kg) on day zero. The rats of groups E+US and NO+US were submitted to different protocols of stress, from the 14th day after the extraction. The protocols were different every day for five consecutive days, which were repeated from the 6th day for five days more. Contralateral medial pterygoid muscles were obtained on the 24th day after the start of the experiment for morphological, metabolic, capillary density, and oxidative stress analysis. The data from capillary density showed a decrease of capillaries in animals subjected to dental extraction, compared with those without extraction and an increase of laminin expression in the group submitted to the unpredictable chronic stress when compared to the unexposed to stress. SDH test revealed a decrease of light fibers in the group submitted to unilateral extraction of molars, compared with this area in the control group. In E+US and NO

  13. Effects of acute and chronic administration of fenproporex on DNA damage parameters in young and adult rats.

    PubMed

    Gonçalves, Cinara L; Rezin, Gislaine T; Ferreira, Gabriela K; Jeremias, Isabela C; Cardoso, Mariane R; Valvassori, Samira S; Munhoz, Bruna J P; Borges, Gabriela D; Bristot, Bruno N; Leffa, Daniela D; Andrade, Vanessa M; Quevedo, João; Streck, Emilio L

    2013-08-01

    Obesity is a chronic and multifactorial disease, whose prevalence is increasing in many countries. Pharmaceutical strategies for the treatment of obesity include drugs that regulate food intake, thermogenesis, fat absorption, and fat metabolism. Fenproporex is the second most commonly consumed amphetamine-based anorectic worldwide; this drug is rapidly converted in vivo into amphetamine, which is associated with neurotoxicity. In this context, the present study evaluated DNA damage parameters in the peripheral blood of young and adult rats submitted to an acute administration and chronic administration of fenproporex. In the acute administration, both young and adult rats received a single injection of fenproporex (6.25, 12.5 or 25 mg/kg i.p.) or vehicle. In the chronic administration, both young and adult rats received one daily injection of fenproporex (6.25, 12.5, or 25 mg/kg i.p.) or Tween for 14 days. 2 h after the last injection, the rats were killed by decapitation and their peripheral blood removed for evaluation of DNA damage parameters by alkaline comet assay. Our study showed that acute administration of fenproporex in young and adult rats presented higher levels of damage index and frequency in the DNA. However, chronic administration of fenproporex in young and adult rats did not alter the levels of DNA damage in both parameters of comet assay. The present findings showed that acute administration of fenproporex promoted damage in DNA, in both young and adult rats. Our results are consistent with other reports which showed that other amphetamine-derived drugs also caused DNA damage. We suggest that the activation of an efficient DNA repair mechanism may occur after chronic exposition to fenproporex. Our results are consistent with other reports that showed some amphetamine-derived drugs also caused DNA damage. PMID:23636618

  14. [Pharmacokinetics of defibrotide in uremic patients undergoing hemodialysis].

    PubMed

    Rossi, R; Farma, A; Maggi, G C; Marelli, A

    1991-12-01

    Defibrotide pharmacokinetics were studied in 6 voluntary healthy subjects and in 10 uremic patients undergoing dialysis during which (instead of heparin) defibrotide was administered to prevent fibrino-formation in the circuit. Blood concentrations of the drug were assessed (expressed with reference to the residual glycidic deoxyribose) during a standard dialysis using defibrotide, 3.5, 15, 30, 45, 60 and 90 minutes after the defibrotide bolus (200 mg) had been injected into the arterial channel. The half-lives of the alpha and beta plasmatic phases were found to be equal at 3.79 and 41.4 min in dialysed subjects and at 1.13 and 16.54 in healthy volunteers. These results indicate that in uremic patients undergoing dialysis at intervals using defibrotide, a longer time is required to eliminate the drug from the circulation. This variation does not however appear to be significant in terms of the therapeutic use of the drug during dialysis.

  15. Critical appraisal of eculizumab for atypical hemolytic uremic syndrome

    PubMed Central

    Palma, Lilian M Pereira; Langman, Craig B

    2016-01-01

    The biology of atypical hemolytic uremic syndrome has been shown to involve inability to limit activation of the alternative complement pathway, with subsequent damage to systemic endothelial beds and the vasculature, resulting in the prototypic findings of a thrombotic microangiopathy. Central to this process is the formation of the terminal membrane attack complex C5b-9. Recently, application of a monoclonal antibody that specifically binds to C5, eculizumab, became available to treat patients with atypical hemolytic uremic syndrome, replacing plasma exchange or infusion as primary therapy. This review focuses on the evidence, based on published clinical trials, case series, and case reports, on the efficacy and safety of this approach. PMID:27110144

  16. Chronic toxicity and carcinogenicity studies with the insecticide endosulfan in rats and mice.

    PubMed

    Hack, R; Ebert, E; Leist, K H

    1995-11-01

    The insecticide endosulfan was evaluated for chronic toxicity and carcinogenicity in long-term feeding studies in both Sprague-Dawley rats and NMRI mice. Dietary concentrations of the test substance were administered to rats at 0, 3, 7.5, 15 and 75 ppm and to mice at 0, 2, 6 and 18 ppm for 24 months each. In the rat study, only the treatment with the highest dose caused a significant reduction of body weight gains of the males and females at 75 ppm. The increased incidence of enlarged kidneys seen at autopsy at 75 ppm in females, and the slightly increased incidence of progressive glomerulonephrosis and slightly increased incidence of renal aneurysms seen histopathologically in the 75 ppm males, make the kidney the target organ in rats. On the basis of these findings a dietary concentration of 15 ppm is considered to be the no-observed-effect level (NOEL) in rats, equivalent to a daily test substance intake of 0.6 mg/kg body weight in males and 0.7 mg/kg body weight in females. In the mouse study, the treatment with 18 ppm caused a significant increase of mortality in the females and a slight (in the first third of the study, significant) reduction of body weight gain in males. Since there were no other substance-related findings, the dietary concentration of 6 ppm is considered to be the NOEL in mice, equivalent to a daily test substance intake of 0.84 mg/kg body weight in males and 0.97 mg/kg body weight in females. An evaluation of all relevant tumour data gained in both studies revealed no differences between control and treated groups. It was concluded, therefore, that endosulfan has no carcinogenic potential.

  17. The treatment of Uygur medicine Dracocephalum moldavica L on chronic mountain sickness rat model

    PubMed Central

    Maimaitiyiming, Dilinuer; Hu, Guangmei; Aikemu, Ainiwaer; Hui, Shi Wen; Zhang, Xiangyang

    2014-01-01

    Aim: Dracocephalum moldavica L, a traditional Uygur medicine, possesses some key cardiac activities. However, till date, no reports are available on the use of D. moldavica against chronic mountain sickness (CMS), which is a medical condition that affects the residents of high altitude. The present study was designed to explore the treatment efficacy of D. moldavica on CMS. Materials and Methods: 80 of the 100 Sprague Dawley rats enrolled were bred in simulated high altitude environment and the remaining 20 rats were kept in the plains. Water and alcohol extracts of D. moldavica were prepared. CMS rat model was prepared, and the rat hearts were removed for histopathological analysis. Blood samples were taken for hematological and biochemical analyses. Rat pulmonary artery pressure was determined to study the treatment efficacy. Results: In the CMS model group, the levels of interleukin-6 (IL-6), C-reactive protein (CRP), and malondialdehyde (MDA) were found to be significantly higher than the control group; while the concentrations of SOD and GSH-Px decreased. D. moldavica could improve these levels, decrease pulmonary artery pressure, and improve the cardiac pathological state. Conclusions: The study results show that IL-6, CRP, MDA, SOD and GSH-Px participate and mediate the formation of CMS and D. moldavica is found to possess noticeable effects on CMS. The present study explored the basics of high altitude sickness and laid the foundation for further progress of Uygur medicines on the treatment of altitude sickness. Further preclinical and clinical studies with more sample size are recommended. PMID:25422549

  18. Enriched environment improves synaptic plasticity and cognitive deficiency in chronic cerebral hypoperfused rats.

    PubMed

    Bayat, Mahnaz; Sharifi, Mohammad Davood; Haghani, Masoud; Shabani, Mohammad

    2015-10-01

    Recent studies have indicated that environmental enrichment (EE) increases the sensorial and social stimulations and leads to strengthened plastic changes in the brain. In models of chronic cerebral hypoperfusion, the ability of an EE to restore the cognition depends on hippocampal synaptic plasticity. The mechanisms for this effect have not, however, been adequately studied. Thus, the aim of the present study was to evaluate the neuroprotective effects and underlying mechanism of environmental enrichment by assessment of spatial memory tasks as well as parameters of synaptic plasticity in rats subjected to occlusion of the bilateral common carotid arteries (2-VO) model. Male Sprague-Dawley rats were used in this study. The model group was established by occlusion of the bilateral common carotid arteries. The animals were tested for learning, memory performance and synaptic plasticity using Morris water maze (MWM), 8-arm Radial Maze (RM), and field potential recording, respectively. The rats subjected to 2-VO in EE exhibited a significantly lower number of working errors and reference errors in RM. Moreover, the enriched environment recovered the memory performance of hypoperfused rats and decreased the swimming time to reach the platform in MWM. In addition, conditions of the environment did not have any effect on baseline synaptic transmission and presynaptic plasticity, but housing the animals in EE rescued the impairment of LTP induction induced by 2-VO. These results suggest that EE ameliorates the LTP and spatial memory impairment induced by 2-VO. Our data indicated that the LTP recovery by EE in the rat models of 2-VO is probably mediated by post-synaptic mechanisms.

  19. Study of hemorheological parameters following partial hepatectomy in rats with chronic aluminium intoxication.

    PubMed

    Contini, María del Carmen; Mahieu, Stella; Bazzoni, Graciela; Bernal, Claudio A; Carnovale, Cristina E

    2006-01-01

    The aim of our work was to analyze the hemorheological parameters following partial hepatectomy in rats with chronic Al-intoxication (Al). Male Wistar rats were randomly assigned into four experimental groups (n=6 each one): Sham (rats subjected to simulated surgery); Al+Sham; Partial Hepatectomy (animals subjected to 65% liver resection) and Al+Partial Hepatectomy. Our results show that both Partial Hepatectomy and Al treatment produce a decrease of plasma cholesterol level, which showed a negative association with Rigidity Index increase (r(s)=-0.6475, p<0.05). The increase of Rigidity Index observed in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy could be related to the increase of the proportion of non-discocytic erythrocytes, particularly stomatocytes, which determines a diminution of the Morphological Index. In the Altreated groups, greater changes in Rigidity Index and Morphological Index were observed. The relative viscosity of blood at a standard haematocrit of 40% was increased in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy as compared to Sham, due to erythrocyte rigidity. On the other hand, we observed that the increase of plasma fibrinogen concentration correlates with augmentation of plasma viscosity (r(s)=0.689, p=0.004) for all the experimental groups studied. The results indicate that both administration of Al and Partial Hepatectomy induce microcytic hypocromic anaemia in the rats reflected by a significant decrease of haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentration. From these results, we conclude that in partially hepatectomized, Al-overloaded rats the decrease in erythrocyte deformability may be an important factor leading to the installation of anaemia. PMID:17148841

  20. [Growth and metabolism of calcium in rats chronically poisoned with aluminium hydroxide].

    PubMed

    Mahieu, S; Calvo, M L; Millen, N; Gonzalez, M; Contini, M C

    1998-01-01

    The effects of aluminum on growth have been studied in rats chronically poisoned with aluminum hydroxide (80 mg/kg b.w.-i.p.-three times a week, during 6 months) and in control rats, between 3 and 26 weeks of age. The growth data was evaluated according to Parks 'theory of feeding an growth. At the end of the poisoning period, the calcium metabolism was studied through a balance of calcium and the determination of bone Ca++ accretion and resorption rates with the aid of 45Ca++. The parathyroid glands function was studied using an indirect method. Treated rats showed a significant decrease in asymptotic weights and in the initial efficiency of food conversion into biomass regarding controls. No differences were observed in food intake between both group. Aluminum affected neither the peak growth rate nor the time necessary to attain maturity. The calcium balance in treated rats was significantly less than in the control group. This was accompanied by a significant increase in the calcium excreted by faces, caused perhaps by a less intestinal absorption. An important amount of aluminum on the surface of the trabecular bone and a reduction in the skeletal Ca++ mass, was observed in all treated rats. Nevertheless there are no differences in the latter when expressed for 100 g of body weight. The rate of skeletal Ca++ accretion was found to be significantly decreased in treated group with respect to controls, without any changes in the bone Ca resorption rate. The reduction in bone turnover revealed by the decrease of Vo+/Vo- was accompanied by less recovery velocity of calcemia in the aluminum treated group, being indirectly related to the parathyroid gland response to calcium depletion. In the model that we studied the decreased bone turnover could have been caused by deposits of aluminum in bone; however there could exist associated factors such as dysfunction in the secretion of PTH, or less affinity between its receptors at the bone level. PMID:9504191

  1. Plasma cortisol activity in rats under conditions of chronic stress supplemented with resveratrol

    PubMed Central

    Hurtado Salazar, Alejandro; Uribe-Velásquez, Luis F

    2012-01-01

    Objective: To determine the activity of cortisol in rats treated with exogenous adrenocorticotropic hormone (ACTH) and a resveratrol supplement. Methods: Forty-eight adult female rats and 16 male rats of the strain (Rattus norvegicus) that were three months old and with body weights ranging from 200 to 250 g for females and 300 to 350 g for males were used and kept in controlled environmental conditions: temperature of 20±2° C and light-dark cycles of 14 and 10 hours. They were fed a balanced diet and had free access to water. The rats were randomly divided into four groups: group 1 - was treated with 5 µg/kg of ACTH i.p. every twelve hours; group 2 - received the same treatment with ACTH plus a grape extract supplement (resveratrol) of 40 mg/kg; group 3 - only received grape extract (resveratrol); and group 4 - received a saline solution (0.9%) i.p. and oral, and served as controls. The experimental design was a 2×2 factorial with two levels ACTH and two polyphenol levels (grape extract). Results: No significant differences were found in blood cortisol concentrations, by day and gender, or by treatment effects (0.75 µg/dL ± 0.11; p <0.001). Conclusion: Results suggest that chronic stress and consumption of resveratrol did not directly alter levels of plasmatic cortisol in either stressed or unstressed rats. It was concluded that the given dosage levels of ACTH possibly did not produce sufficient stimulation of the adrenal gland for these animals. PMID:24893196

  2. [Growth and metabolism of calcium in rats chronically poisoned with aluminium hydroxide].

    PubMed

    Mahieu, S; Calvo, M L; Millen, N; Gonzalez, M; Contini, M C

    1998-01-01

    The effects of aluminum on growth have been studied in rats chronically poisoned with aluminum hydroxide (80 mg/kg b.w.-i.p.-three times a week, during 6 months) and in control rats, between 3 and 26 weeks of age. The growth data was evaluated according to Parks 'theory of feeding an growth. At the end of the poisoning period, the calcium metabolism was studied through a balance of calcium and the determination of bone Ca++ accretion and resorption rates with the aid of 45Ca++. The parathyroid glands function was studied using an indirect method. Treated rats showed a significant decrease in asymptotic weights and in the initial efficiency of food conversion into biomass regarding controls. No differences were observed in food intake between both group. Aluminum affected neither the peak growth rate nor the time necessary to attain maturity. The calcium balance in treated rats was significantly less than in the control group. This was accompanied by a significant increase in the calcium excreted by faces, caused perhaps by a less intestinal absorption. An important amount of aluminum on the surface of the trabecular bone and a reduction in the skeletal Ca++ mass, was observed in all treated rats. Nevertheless there are no differences in the latter when expressed for 100 g of body weight. The rate of skeletal Ca++ accretion was found to be significantly decreased in treated group with respect to controls, without any changes in the bone Ca resorption rate. The reduction in bone turnover revealed by the decrease of Vo+/Vo- was accompanied by less recovery velocity of calcemia in the aluminum treated group, being indirectly related to the parathyroid gland response to calcium depletion. In the model that we studied the decreased bone turnover could have been caused by deposits of aluminum in bone; however there could exist associated factors such as dysfunction in the secretion of PTH, or less affinity between its receptors at the bone level.

  3. Study of hemorheological parameters following partial hepatectomy in rats with chronic aluminium intoxication.

    PubMed

    Contini, María del Carmen; Mahieu, Stella; Bazzoni, Graciela; Bernal, Claudio A; Carnovale, Cristina E

    2006-01-01

    The aim of our work was to analyze the hemorheological parameters following partial hepatectomy in rats with chronic Al-intoxication (Al). Male Wistar rats were randomly assigned into four experimental groups (n=6 each one): Sham (rats subjected to simulated surgery); Al+Sham; Partial Hepatectomy (animals subjected to 65% liver resection) and Al+Partial Hepatectomy. Our results show that both Partial Hepatectomy and Al treatment produce a decrease of plasma cholesterol level, which showed a negative association with Rigidity Index increase (r(s)=-0.6475, p<0.05). The increase of Rigidity Index observed in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy could be related to the increase of the proportion of non-discocytic erythrocytes, particularly stomatocytes, which determines a diminution of the Morphological Index. In the Altreated groups, greater changes in Rigidity Index and Morphological Index were observed. The relative viscosity of blood at a standard haematocrit of 40% was increased in Partial Hepatectomy, Al+Sham and Al+Partial Hepatectomy as compared to Sham, due to erythrocyte rigidity. On the other hand, we observed that the increase of plasma fibrinogen concentration correlates with augmentation of plasma viscosity (r(s)=0.689, p=0.004) for all the experimental groups studied. The results indicate that both administration of Al and Partial Hepatectomy induce microcytic hypocromic anaemia in the rats reflected by a significant decrease of haematocrit, mean corpuscular volume and mean corpuscular haemoglobin concentration. From these results, we conclude that in partially hepatectomized, Al-overloaded rats the decrease in erythrocyte deformability may be an important factor leading to the installation of anaemia.

  4. Chronic trimethyltin chloride exposure and the development of kidney stones in rats.

    PubMed

    Ren, Xuefeng; Wu, Xin; Sui, Gang; Gong, Zhihong; Yawson, Emmanuel; Wu, Banghua; Lai, Guanchao; Ruan, Xiaolin; Gao, Hongbin; Zhou, Feng; Su, Bing; Olson, James R; Tang, Xiaojiang

    2015-05-01

    We recently reported that occupational exposure to trimethyltin (TMT) is a risk factor for developing kidney stones. To further examine the association between TMT exposure and the formation of kidney stones, we conducted a 180-day animal study and exposed the randomly grouped Sprague-Dawley (SD) rats to TMT in the drinking water at doses of 0, 8.2, 32.8 and 131.3 µg kg(-1) day(-1). Transient behavioral changes were observed in the high-dose group during the first 2 weeks of exposure. TMT exposure led to a significant dose-dependent inhibition of renal H(+)/K(+)-ATPase and an increase in urinary pH. In comparison to no kidney stones being identified in the control and the lowest dose group, 1 rat in the 32.8 µg kg(-1) day(-1) dose group and 3 out of 9 rats in the 131.3 µg kg(-1) day(-1) dose group were found to have stones in the kidney/urinary tract. Pathological analysis showed that more wide spread calcium disposition was observed in kidneys of rats with TMT exposure compared with the rats in the control group. However, X-ray diffraction (XRD) analysis found that the kidney stones were mainly composed of struvite with the formula: NH4MgPO4 6H2O, while calcium-containing components were also detected. Together, this study further demonstrates through animal studies that chronic exposure to a relatively low level of TMT induces nephrotoxicity and increases the risk for developing kidney stones.

  5. Sex differences in the Nociceptin/Orphanin FQ system in rat spinal cord following chronic morphine treatment

    PubMed Central

    Zhang, Yong; Donica, Courtney L.; Standifer, Kelly M.

    2016-01-01

    Nociceptin/Orphanin FQ (N/OFQ) appears to contribute to the development of morphine tolerance, as blockade of its actions will block or reverse the process. To better understand the contribution of N/OFQ to the development of morphine tolerance, this study examined the effect of chronic morphine treatment on levels of N/OFQ and levels and activity of the N/OFQ peptide (NOP) receptor in spinal cord (SC) from male and female rats. Both male and female Wistar rats showed less responsiveness to morphine after subcutaneous injection of escalating doses of morphine (10, 20, 40, 60 and 80 mg/kg, respectively) twice daily for five consecutive days. Male rats were more tolerant to the antinociceptive actions of morphine than females. The N/OFQ content of SC extracts was higher in females than in males, regardless of treatment; following chronic morphine treatment the difference in N/OFQ levels between males and females was more pronounced. N/OFQ content in cerebrospinal fluid (CSF) was reduced 40% in male and 16% in female rats with chronic morphine exposure, but increased in periaqueductal grey of both sexes. Chronic morphine treatment increased NOP receptor levels 173% in males and 137% in females, while decreasing affinity in both. Chronic morphine increased the efficacy of N/OFQ-stimulated [35S]GTPγS binding to SC membranes from male rats, consistent with increased receptor levels. Taken together, these findings demonstrate sex differences in N/OFQ–NOP receptor expression and NOP receptor activity following chronic morphine treatment. They also suggest interplay between endogenous N/OFQ and chronic morphine treatment that results in nociceptive modulation. PMID:22575074

  6. Lymphangiogenesis and Lymphatic Absorption Are Related and Increased in Chronic Kidney Failure, Independent of Exposure to Dialysis Solutions.

    PubMed

    Vlahu, Carmen A; de Graaff, Marijke; Aten, Jan; Struijk, Dirk G; Krediet, Raymond T

    2015-01-01

    Increased lymphatic absorption might contribute to ultrafiltration failure in peritoneal dialysis (PD). Lymphangiogenesis develops during PD, but little is known about the relationship between its morphologic and functional parameters. The relationships between lymph vessel density, the effective lymphatic absorption rate (ELAR), and fibrosis were investigated in a rat model of chronic kidney failure (CKD) with exposure to dialysis solutions. Wistar rats (n = 44) were allocated to these groups: NKF (normal kidney function), CKD (70% nephrectomy), CKDD [CKD, with daily intraperitoneal (i.p.) Dianeal 3.86% (Baxter Healthcare BV, Utrecht, Netherlands)], CKDP [CKD, with daily i.p. Physioneal 3.86% (Baxter Healthcare BV)]. After 16 weeks, a peritoneal function test was performed, and the ELAR was calculated from the disappearance rate of i.p. dextran 70. The lymph vessel profile density (LVPD) was assessed using STEPanizer image analysis (Java application from Tschanz SA, Bern, Germany) of omental sections after anti-podoplanin immunostaining. Fibrosis was quantified by picro-sirius red staining. The LVPD was significantly increased in CKD rats compared with NKF rats, and no additional effect of dialysis solutions was present. The ELAR was increased in uremic rats compared with NKF rats. For all rats together, the LVPD correlated positively with the ELAR and with the amount of fibrosis. Chronic kidney disease itself induces lymphangiogenesis and fibrosis and increases the ELAR, independent of exposure to dialysis fluids. The ELAR is related to the LVPD in peritoneal tissue.

  7. Lymphangiogenesis and Lymphatic Absorption Are Related and Increased in Chronic Kidney Failure, Independent of Exposure to Dialysis Solutions.

    PubMed

    Vlahu, Carmen A; de Graaff, Marijke; Aten, Jan; Struijk, Dirk G; Krediet, Raymond T

    2015-01-01

    Increased lymphatic absorption might contribute to ultrafiltration failure in peritoneal dialysis (PD). Lymphangiogenesis develops during PD, but little is known about the relationship between its morphologic and functional parameters. The relationships between lymph vessel density, the effective lymphatic absorption rate (ELAR), and fibrosis were investigated in a rat model of chronic kidney failure (CKD) with exposure to dialysis solutions. Wistar rats (n = 44) were allocated to these groups: NKF (normal kidney function), CKD (70% nephrectomy), CKDD [CKD, with daily intraperitoneal (i.p.) Dianeal 3.86% (Baxter Healthcare BV, Utrecht, Netherlands)], CKDP [CKD, with daily i.p. Physioneal 3.86% (Baxter Healthcare BV)]. After 16 weeks, a peritoneal function test was performed, and the ELAR was calculated from the disappearance rate of i.p. dextran 70. The lymph vessel profile density (LVPD) was assessed using STEPanizer image analysis (Java application from Tschanz SA, Bern, Germany) of omental sections after anti-podoplanin immunostaining. Fibrosis was quantified by picro-sirius red staining. The LVPD was significantly increased in CKD rats compared with NKF rats, and no additional effect of dialysis solutions was present. The ELAR was increased in uremic rats compared with NKF rats. For all rats together, the LVPD correlated positively with the ELAR and with the amount of fibrosis. Chronic kidney disease itself induces lymphangiogenesis and fibrosis and increases the ELAR, independent of exposure to dialysis fluids. The ELAR is related to the LVPD in peritoneal tissue. PMID:26714383

  8. Chronic Alcohol Treatment in Rats Alters Sleep by Fragmenting Periods of Vigilance Cycling in the Light Period with Extended Wakenings

    PubMed Central

    Mukherjee, Sanjib; Simasko, Steven M.

    2009-01-01

    Studies have shown that disturbed sleep produced by chronic alcohol abuse in humans can predict relapse drinking after periods of abstinence. How alcohol produces disturbed sleep remains unknown. In this study we used a novel analysis of sleep to examine the effects of alcohol on sleep patterns in rats. This analysis separates waking into multiple components and defines a period labeled vigilance cycling (VC) in which the rat rapidly cycles through various vigilance states. These VC episodes are separated by long duration wake periods (LDW). We find that 6 weeks of alcohol (6% in a liquid diet) caused fragmentation of extended VC episodes that normally occur in the light period. However, total daily amounts of slow-wave sleep (SWS) and rapid-eye movement sleep (REMS) remained constant. The daily amount of wake, SWS, and REMS remained constant because the alcohol treated rats increased the amount of VC in the dark period, and the sleep nature of VC in the dark period became more intense. In addition, we observed more wake and less REMS early in the light period in alcohol treated rats. All effects completely reversed by day 16 of alcohol withdrawal. Comparison of the effects of chronic alcohol to acute alcohol exposure demonstrated the effects of chronic alcohol are due to adaptation and not the acute presence of alcohol. The effects of chronic alcohol treatment in rats mimic the effects reported in humans (REMS suppression, difficulty falling asleep, and difficulty remaining asleep). PMID:19014977

  9. Mitochondrial dysfunction and lipid peroxidation in rat frontal cortex by chronic NMDA administration can be partially prevented by lithium treatment.

    PubMed

    Kim, Helena K; Isaacs-Trepanier, Cameron; Elmi, Nika; Rapoport, Stanley I; Andreazza, Ana C

    2016-05-01

    Chronic N-methyl-d-aspartate (NMDA) administration to rats may be a model to investigate excitotoxicity mediated by glutamatergic hyperactivity, and lithium has been reported to be neuroprotective. We hypothesized that glutamatergic hyperactivity in chronic NMDA injected rats would cause mitochondrial dysfunction and lipid peroxidation in the brain, and that chronic lithium treatment would ameliorate some of these NMDA-induced alterations. Rats treated with lithium for 6 weeks were injected i.p. 25 mg/kg NMDA on a daily basis for the last 21 days of lithium treatment. Brain was removed and frontal cortex was analyzed. Chronic NMDA decreased brain levels of mitochondrial complex I and III, and increased levels of the lipid oxidation products, 8-isoprostane and 4-hydroxynonenal, compared with non-NMDA injected rats. Lithium treatment prevented the NMDA-induced increments in 8-isoprostane and 4-hydroxynonenal. Our findings suggest that increased chronic activation of NMDA receptors can induce alterations in electron transport chain complexes I and III and in lipid peroxidation in brain. The NMDA-induced changes may contribute to glutamate-mediated excitotoxicity, which plays a role in brain diseases such as bipolar disorder. Lithium treatment prevented changes in 8-isoprostane and 4-hydroxynonenal, which may contribute to lithium's reported neuroprotective effect and efficacy in bipolar disorder.

  10. Sea buckthorn (Hippophae rhamnoides L.) oil protects against chronic stress-induced inhibitory function of natural killer cells in rats.

    PubMed

    Diandong, Hou; Feng, Gu; Zaifu, Liang; Helland, Timothy; Weixin, Fu; Liping, Cai

    2016-03-01

    Chronic stress can suppress natural killer (NK) cell activity; this may also be related to the effect of stress on the neuroendocrine-immune network. Sea buckthorn (SBT) (Hippophae rhamnoides L.) is a thorny nitrogen fixing deciduous shrub, native to both Europe and Asia. It has been used as a medicinal plant in Tibetan and Mongolian traditional medicines. SBT has multifarious medical properties, including anti-fatigue as well as immunoregulatory effects. This study reports the effects of SBT oil with regard to the cytotoxicity and quantity of NK cells in the blood of a chronic-stress rat model, in addition to its mechanisms on the neuroendocrine-immune network. These results show that SBT oil, given by gavage to rats with chronic stress, could increase the following: body weight, NK cell quantities, and cytotoxicity, as well as the expression of perforin and granzyme B. The results also show that SBT oil in rats with chronic stress could suppress cortisol, ACTH, IL-1β and TNF-α levels, in addition to increasing 5-HT and IFN-γ serum levels. This leads to suggest that SBT oil, in rats with chronic stress, can increase NK cell cytotoxicity by upregulating the expression of perforin and granzyme B, thus causing associated effects of SBT oil on the neuroendocrine-immune network. PMID:26684638

  11. Ameliorating Adriamycin-Induced Chronic Kidney Disease in Rats by Orally Administrated Cardiotoxin from Naja naja atra Venom.

    PubMed

    Ding, Zhi-Hui; Xu, Li-Min; Wang, Shu-Zhi; Kou, Jian-Qun; Xu, Yin-Li; Chen, Cao-Xin; Yu, Hong-Pei; Qin, Zheng-Hong; Xie, Yan

    2014-01-01

    Previous studies reported the oral administration of Naja naja atra venom (NNAV) reduced adriamycin-induced chronic kidney damage. This study investigated the effects of intragastric administrated cardiotoxin from Naja naja atra venom on chronic kidney disease in rats. Wistar rats were injected with adriamycin (ADR; 6 mg/kg body weight) via the tail vein to induce chronic kidney disease. The cardiotoxin was administrated daily by intragastric injection at doses of 45, 90, and 180  μ g/kg body weight until the end of the protocol. The rats were placed in metabolic cages for 24 hours to collect urine, for determination of proteinuria, once a week. After 6 weeks, the rats were sacrificed to determine serum profiles relevant to chronic kidney disease, including albumin, total cholesterol, phosphorus, blood urea nitrogen, and serum creatinine. Kidney histology was examined with hematoxylin and eosin, periodic acid-Schiff, and Masson's trichrome staining. The levels of kidney podocin were analyzed by Western blot analysis and immunofluorescence. We found that cardiotoxin reduced proteinuria and can improve biological parameters in the adriamycin-induced kidney disease model. Cardiotoxin also reduced adriamycin-induced kidney pathology, suggesting that cardiotoxin is an active component of NNAV for ameliorating adriamycin-induced kidney damage and may have a potential therapeutic value on chronic kidney disease.

  12. Acute and chronic head-down tail suspension diminishes cerebral perfusion in rats

    NASA Technical Reports Server (NTRS)

    Wilkerson, M. Keith; Colleran, Patrick N.; Delp, Michael D.

    2002-01-01

    The purpose of this study was to test the hypothesis that regional brain blood flow and vascular resistance are altered by acute and chronic head-down tail suspension (HDT). Regional cerebral blood flow, arterial pressure, heart rate, and vascular resistance were measured in a group of control rats during normal standing and following 10 min of HDT and in two other groups of rats after 7 and 28 days of HDT. Heart rate was not different among conditions, whereas mean arterial pressure was elevated at 10 min of HDT relative to the other conditions. Total brain blood flow was reduced from that during standing by 48, 24, and 27% following 10 min and 7 and 28 days of HDT, respectively. Regional blood flows to all cerebral tissues and the eyes were reduced with 10 min of HDT and remained lower in the eye, olfactory bulbs, left and right cerebrum, thalamic region, and the midbrain with 7 and 28 days of HDT. Total brain vascular resistance was 116, 44, and 38% greater following 10 min and 7 and 28 days of HDT, respectively, relative to that during control standing. Vascular resistance was elevated in all cerebral regions with 10 min of HDT and remained higher than control levels in most brain regions. These results demonstrate that HDT results in chronic elevations in total and regional cerebral vascular resistance, and this may be the underlying stimulus for the HDT-induced smooth muscle hypertrophy of cerebral resistance arteries.

  13. The effects of chronic exercise on metabolic and reproductive functions in male rats.

    PubMed

    Woody, C J; Weber, S L; Laubach, H E; Ingram-Willey, V; Amini-Alashti, P; Sturbaum, B A

    1998-01-01

    Previous studies concerning the effects of swimming on various endocrine gland functions have been performed. Our study was thus designed to analyze the effects of chronic exercise (swimming) on the resting metabolic rates (RMR) of adult rats. Most of the protocols used a water temperature of 33 C. It is our contention that such a protocol is not exclusively an exercise stress, but also a hypothermic stress. The protocol of our study was designed in a way that hypothermic stress was not part of the exercise stress. Male rats were swam in 36 C water for 3 hours a day, 5 days a week for 4 months. RMR of the animals were determined 24 h after the next to last swim session. Plasma hormone levels and epididymal sperm concentrations were determined in animals sacrificed 24 h after the last swim period. Exercising animals had a RMR 16% greater than that of control animals (p < 0.02), yet total and free thyroxine and total and free triiodothyronine were not significantly elevated. Neither plasma testosterone nor epididymal sperm counts were significantly reduced in the exercising animals. It appears that chronic exercise produces an elevation in RMR which is unrelated to thyroid gland activity and does not suppress the hypothalamic-pituitary-gonadal axis.

  14. Effects of acute and chronic immobilization stress on rat Leydig cell steroidogenesis.

    PubMed

    Marić, D; Kostić, T; Kovacević, R

    1996-06-01

    In rats, acute immobilization (IMO) stress (2 h) induced a fall in the serum androgen concentrations (T+DHT) without detectable changes in serum luteinizing hormone (LH) values. In vitro studies, using a suspension of Leydig cells from adult rat testis, demonstrated that acute stress inhibited conversion of progesterone (P) or 17hydroxyprogesterone (17OHP) to T while conversion of androstendione (delta 4 A) was not affected. Acute IMO reduced activity of 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and decreased basal and hCG-stimulated progesterone and androgen production. Chronic IMO stress (2 h daily for 10 days) induced a decrease in serum androgen level with decline in serum LH values. In vitro, hCG-stimulated progesterone and androgen production by suspension of Leydig cells, as well as conversion of P and 17OHP to T were not significantly altered. Our data demonstrates that acute IMO stress impaired testicular steroidogenesis primarily at the testicular level (decreasing the activity of certain enzymes), while chronic IMO stress exerts the effect mainly on the hypothalamic-pituitary axis; reduced serum LH levels elicit a decrease in serum androgen levels.

  15. Alterations induced by chronic lead exposure on the cells of circadian pacemaker of developing rats

    PubMed Central

    Rojas-Castañeda, Julio César; Vigueras-Villaseñor, Rosa María; Rojas, Patricia; Chávez-Saldaña, Margarita; Pérez, Oscar Gutiérrez; Montes, Sergio; Ríos, Camilo

    2011-01-01

    Lead (Pb) exposure alters the temporal organization of several physiological and behavioural processes in which the suprachiasmatic nucleus (SCN) of the hypothalamus plays a fundamental role. In this study, we evaluated the effects of chronic early Pb exposure (CePbe) on the morphology, cellular density and relative optical density (OD) in the cells of the SCN of male rats. Female Wistar rats were exposed during gestation and lactation to a Pb solution containing 320 ppm of Pb acetate through drinking water. After weaning, the pups were maintained with the same drinking water until sacrificed at 90 days of age. Pb levels in the blood, hypothalamus, hippocampus and prefrontal cortex were significantly increased in the experimental group. Chronic early Pb exposure induced a significant increase in the minor and major axes and somatic area of vasoactive intestinal polypeptide (VIP)- and vasopressin (VP)-immunoreactive neurons. The density of VIP-, VP- and glial fibrillary acidic protein (GFAP)-immunoreactive cells showed a significant decrease in the experimental group. OD analysis showed a significant increase in VIP neurons of the experimental group. The results showed that CePbe induced alterations in the cells of the SCN, as evidenced by modifications in soma morphology, cellular density and OD in circadian pacemaker cells. These findings provide a morphological and cellular basis for deficits in circadian rhythms documented in Pb-exposed animals. PMID:21324006

  16. Protective effect of Clerodendrum colebrookianum Walp., on acute and chronic inflammation in rats

    PubMed Central

    Deb, Lokesh; Dey, Amitabha; Sakthivel, G.; Bhattamishra, Subrat Kumar; Dutta, Amitsankar

    2013-01-01

    Aim: To evaluate antioxidant, anti-inflammatory potential of the aqueous extracts and its aqueous, n-butanol, ethyl-acetate, and chloroform fractions of Clerodendrum colebrookianum Walp. leaves. Materials and Methods: In this present study, all the test samples were evaluated on in-vivo inflammatory model such as carrageenan and histamine-induced acute-inflammation and cotton pellet induced granuloma formation in albino male rats. Test samples were also employed in in-vitro assays like DPPH* free radical scavenging activity and COX inhibition assay. Results: The test samples at the dose of 200mg/kg/p.o. were found to cause significant inhibition of carrageenan and histamine-induced inflammation and cotton pallet-induced granuloma formation on acute and chronic inflammation in rats. The test samples, except n-butanol fraction, exhibited inhibitory effect for both COX-1 and COX-2, in in-vitro assay but their percentage of inhibition values differs from each other. The test samples (aqueous extracts, aqueous, n-butanol, ethyl-acetate, and chloroform fractions) at 100 μg concentration exhibits 54.37%, 33.88%, 62.85%, 56.28%, and 57.48% DPPH* radical-scavenging effect respectively in in-vitro antioxidant study. Conclusion: These observations established the anti-inflammatory effect of C. colebrookianum leaves in acute and chronic stages of inflammation by free radical scavenging and inhibition of COX-1 and COX-2. PMID:24014914

  17. Nitric Oxide and Superoxide Anion Balance in Rats Exposed to Chronic and Long Term Intermittent Hypoxia

    PubMed Central

    Siques, Patricia; López de Pablo, Ángel Luis; Brito, Julio; Arribas, Silvia M.; Naveas, Nelson; González, M. Carmen; León-Velarde, Fabiola; López, M. Rosario

    2014-01-01

    Work at high altitude in shifts exposes humans to a new form of chronic intermittent hypoxia, with still unknown health consequences. We have established a rat model resembling this situation, which develops a milder form of right ventricular hypertrophy and pulmonary artery remodelling compared to continuous chronic exposure. We aimed to compare the alterations in pulmonary artery nitric oxide (NO) availability induced by these forms of hypoxia and the mechanisms implicated. Rats were exposed for 46 days to normoxia or hypobaric hypoxia, either continuous (CH) or intermittent (2 day shifts, CIH2x2), and assessed: NO and superoxide anion availability (fluorescent indicators and confocal microscopy); expression of phosphorylated endothelial NO synthase (eNOS), NADPH-oxidase (p22phox), and 3-nitrotyrosine (western blotting); and NADPH-oxidase location (immunohistochemistry). Compared to normoxia, (1) NO availability was reduced and superoxide anion was increased in both hypoxic groups, with a larger effect in CH, (2) eNOS expression was only reduced in CH, (3) NADPH-oxidase was similarly increased in both hypoxic groups, and (4) 3-nitrotyrosine was increased to a larger extent in CH. In conclusion, intermittent hypoxia reduces NO availability through superoxide anion destruction, without reducing its synthesis, while continuous hypoxia affects both, producing larger nitrosative damage which could be related to the more severe cardiovascular alterations. PMID:24719876

  18. Chronic effects of interleukin-1 beta on fever, oxygen consumption and food intake in the rat.

    PubMed

    Busbridge, N J; Dascombe, M J; Rothwell, N J

    1993-04-01

    Chronic subcutaneous infusion (from osmotic minipumps) of IL-1 beta (1 microgram/d) in male rats over seven days caused transient (1-3 d) increases in body temperature and reductions in body weight gain and food intake. By day 3, when colonic temperature was similar for vehicle and IL-1 infused groups, the acute responses (increases in temperature and VO2) to a maximal dose (1 microgram, sc) of IL-1 beta was almost identical in all animals. In a separate study intraperitoneal infusion of the same dose of IL-1 beta (1 microgram/d) increased the duration of changes in body temperature, weight and food intake, compared to subcutaneous infusion. In further groups of rats, pyrogenic responses to daily injections of IL-1 beta (1 microgram ip) were sustained for the entire 7 d period, but this treatment did not affect body weight. These data demonstrate that tolerance to infusion of IL-1 is not accompanied by reduced maximal responses to acute administration of IL-1, and indicate that more sustained effects of IL-1 are achieved by intraperitoneal rather than subcutaneous infusions, or by repetitive daily injections of the cytokine. These observations indicate that low levels of IL-1 release, maintained over periods of several days could be responsible for changes in body temperature and energy balance during chronic infections or inflammation.

  19. Effect of chronic nicotine pre-treatment on phencyclidine (PCP) disposition in the rat.

    PubMed

    Vadlamani, N L; Pontani, R B; Misra, A L

    1983-09-01

    Disposition of [3H] phencyclidine (5 mg kg-1 i.p.) in brain, liver and plasma of rats treated chronically with 0.9% saline or nicotine (1 mg kg-1 s.c. twice a day for 11 days) was studied using a method possessing high sensitivity and specificity for PCP. No significant differences were observed in the values of PCP in plasma and tissues and in brain or liver to plasma PCP concentration ratios in the 2 groups 0.5, 1, 2 hr after [3H] PCP injection. With the exception of the value of PCP metabolites in plasma at 0.5 hr, the PCP metabolites concentrations were also not significantly different in the 2 groups. Data suggested that chronic nicotine pretreatment of rats did not affect the disposition of PCP and the potentiation of PCP-induced locomotor stimulant effects by nicotine possibly involves the additive pharmacodynamic interaction of 2 compounds at the level of the central nervous system. PMID:6651404

  20. Effects of chronic treatment with methylphenidate on oxidative stress and inflammation in hippocampus of adult rats.

    PubMed

    Motaghinejad, Majid; Motevalian, Manijeh; Shabab, Behnaz

    2016-04-21

    Methylphenidate (MPH) is a central stimulant, prescribed for the treatment of attention deficit/hyperactivity disorder. The long-term behavioral consequences of MPH treatment are unknown. In this study, the oxidative stress and neuroinflammation induced by various doses of MPH were investigated. Forty adult male rats were divided into 5 groups; and treated with different doses of MPH for 21 days. Twenty four hours after drug treatment, Open Field Test (OFT) was performed in all animals. At the end of the study, blood cortisol level (BCL) was measured and hippocampus was isolated and oxidative stress and inflammation parameters and histological changes were analyzed. Chronic MPH at all doses decreased central square entries, number of rearing, ambulation distance and time spent in central square in OFT. BCL increased in doses 10 and 20mg/kg of MPH. Furthermore, MPH in all doses markedly increased lipid peroxidation, mitochondrial oxidized glutathione (GSSG) level, Interleukin 1β (IL-1β) and Tumor Necrosis Factor α (TNF-α) in isolated hippocampus. MPH (10 and 20mg/kg) treated groups had decreased mitochondrial reduced glutathione (GSH) content, and reduced superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione reductase (GRx) activities. 10 and 20mg/kg of MPH change cell density and morphology of cells in Dentate Gyrus (DG) and CA1 areas of hippocampus. Chronic treatment with high doses of MPH can cause oxidative stress, neuroinflammation and neurodegeneration in hippocampus of adult rats.

  1. Dehydroepiandrosterone reverses chronic hypoxia/reoxygenation-induced right ventricular dysfunction in rats.

    PubMed

    Dumas de La Roque, Eric; Bellance, Nadège; Rossignol, Rodrigue; Begueret, Hugues; Billaud, Marie; dos Santos, Pierre; Ducret, Thomas; Marthan, Roger; Dahan, Diana; Ramos-Barbón, David; Amor-Carro, Óscar; Savineau, Jean-Pierre; Fayon, Michael

    2012-12-01

    Dehydroepiandrosterone (DHEA) prevents chronic hypoxia-induced pulmonary hypertension and associated right ventricle dysfunction in rats. In this animal model, reoxygenation following hypoxia reverses pulmonary hypertension but not right ventricle dysfunction. We thus studied the effect of DHEA on the right ventricle after reoxygenation, i.e. after a normoxic recovery phase secondary to chronic hypoxia in rats. Right ventricle function was assessed in vivo by Doppler echocardiography and in vitro by the isolated perfused heart technique in three groups of animals: control, recovery (21 days of hypoxia followed by 21 days of normoxia) and recovery DHEA (30 mg · kg(-1) every 2 days during the recovery phase). Right ventricle tissue was assessed by optical and electron microscopy. DHEA abolished right ventricle diastolic dysfunction, as the echographic E wave remained close to that of controls (mean ± SD 76.5 ± 2.4 and 79.7 ± 1.7 cm · s(-1), respectively), whereas it was diminished to 40.3 ± 3.7 in the recovery group. DHEA also abolished right ventricle systolic dysfunction, as shown by the inhibition of the increase in the slope of the pressure-volume curve in isolated heart. The DHEA effect was related to cardiac myocytes proliferation. In conclusion, DHEA prevents right ventricle dysfunction in this animal model by preventing cardiomyocyte alteration.

  2. The effects of chronic administration of nandrolone decanoate on redox status in exercised rats.

    PubMed

    Nikolic, Tamara; Zivkovic, Vladimir; Jevdjevic, Maja; Djuric, Marko; Srejovic, Ivan; Djuric, Dragan; Jeremic, Nevena; Djuric, Dusan; Bolevich, Sergey; Jakovljevic, Vladimir

    2016-01-01

    For the past 40 years, anabolic-androgenic steroids have been used by a wide variety of athletes with the hope of improving their training, endurance, and performance. The aim of this study was to examine the chronic effects of nandrolone decanoate (20 mg/kg, s.c, Deca-Durabolin DECA(®)) on oxidative stress biomarkers in the hearts of sedentary and exercised rats. The male Wistar albino rats (n = 180, four groups with three subgroups, 15 per subgroup, age 10 weeks, body mass 200-220 g) were sacrificed, and in the collected samples of blood, the following markers of oxidative stress were measured spectrophotometrically: (1) index of lipid peroxidation (measured as TBARS-thiobarbituric acid reactive substances); (2) nitrites (NO2 (-)); (3) hydrogen peroxide (H2O2); (4) superoxide anion radical (O2 (-)), and superoxide dismutase, catalase, and glutathione reductase. The results clearly show that the impact of ND alone, or in combination with physical training in general, is mildly pro-oxidative. The chronic physical training probably induces the protective antioxidant enzyme system , which may be of clinical interest when faced with overdosage of this drug. PMID:26361780

  3. The role of adenosine in the early respiratory and cardiovascular changes evoked by chronic hypoxia in the rat

    PubMed Central

    Walsh, Martin P; Marshall, Janice M

    2006-01-01

    Experiments were performed on anaesthetized normoxic (N) rats and chronically hypoxic rats that had been exposed to 12% O2 for 1, 3 or 7 days (1, 3 or 7CH rats). The adenosine A1 receptor antagonist DPCPX did not affect the resting hyperventilation of 1–7CH rats breathing 12% O2 and increased resting heart rate (HR) in 1CH rats only. DPCPX partially restored the decreased baseline arterial pressure (ABP) and increased femoral vascular conductance (FVC) of 1 and 3CH rats, but had no effect in N or 7CH rats. DPCPX also attenuated the decrease in arterial blood pressure (ABP) and increase in FVC evoked by acute hypoxia in N and 1–7CH rats. The non-selective adenosine receptor antagonist 8-SPT had no further effect on baselines or cardiovascular responses to acute hypoxia, but attenuated the hypoxia-evoked increase in respiratory frequency in 1–7CH rats. In N, and 1 and 3CH rats, the inducible nitric oxide synthase (iNOS) inhibitor aminoguanidine had no effect on baselines or increases in FVC evoked by acetylcholine. We propose: (i) that tonically released adenosine acting on A1 receptors reduces HR in 1CH rats and stimulates endothelial NOS in 1 and 3CH rats to decrease ABP and increase FVC, the remaining NO-dependent tonic vasodilatation being independent of iNOS activity; (ii) that in 7CH rats, tonic adenosine release has waned; (iii) that in 1–7CH rats, adenosine released by acute hypoxia stimulates A1 but not A2 receptors to produce muscle vasodilatation, and stimulates carotid body A2 receptors to increase respiration. PMID:16690710

  4. Neutrophil function in an experimental model of hemolytic uremic syndrome.

    PubMed

    Vedanarayanan, V V; Kaplan, B S; Fong, J S

    1987-03-01

    To understand the role of neutrophil leukocytosis in hemolytic uremic syndrome, we studied the changes in neutrophil function in the modified generalized Shwartzman reaction in rabbits. This model resembles hemolytic uremic syndrome associated with endotoxemia. At the end of an endotoxin infusion, we observed leukopenia, thrombocytopenia, and a decrease in hematocrit associated with schistocytosis. Plasma B-glucuronidase levels increased and this was associated with a decrease in neutrophil content of the enzyme. The chemotactic index and neutrophil aggregation to zymosan-activated serum were impaired compared to controls. The neutrophil procoagulant content increased after endotoxin infusion. The serum creatinine concentration and proteinuria increased in the endotoxin-treated animals. The changes returned to normal by 48 h. Renal cortical malondialdehyde, a reflection of lipid peroxidation, was higher in the endotoxin-treated animals than in the controls. We have shown enzyme release by neutrophils, impairment of chemotaxis and aggregation, increased procoagulant content in neutrophils, and evidence of lipid peroxidation in renal cortical tissue in this model. These observations raise the possibility that leukocytes may have a role in the pathogenesis of the hemolytic uremic syndrome. PMID:3550673

  5. Chronic skeletal muscle ischemia preserves coronary flow in the ischemic rat heart.

    PubMed

    Varnavas, Varnavas C; Kontaras, Konstantinos; Glava, Chryssoula; Maniotis, Christos D; Koutouzis, Michael; Baltogiannis, Giannis G; Papalois, Apostolos; Kolettis, Theofilos M; Kyriakides, Zenon S

    2011-10-01

    Chronic skeletal muscle ischemia confers cytoprotection to the ventricular myocardium during infarction, but the underlying mechanisms remain unclear. Although neovascularization in the left ventricular myocardium has been proposed as a possible mechanism, the functional capacity of such vessels has not been studied. We examined the effects of chronic limb ischemia on infarct size, coronary blood flow, and left ventricular function after ischemia-reperfusion. Hindlimb ischemia was induced in 65 Wistar rats by excision of the left femoral artery, whereas 65 rats were sham operated. After 4 wk, myocardial infarction was generated by permanent coronary artery ligatio