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Sample records for adult rats showed

  1. Astrocytes from adult Wistar rats aged in vitro show changes in glial functions.

    PubMed

    Souza, Débora Guerini; Bellaver, Bruna; Raupp, Gustavo Santos; Souza, Diogo Onofre; Quincozes-Santos, André

    2015-11-01

    Astrocytes, the most versatile cells of the central nervous system, play an important role in the regulation of neurotransmitter homeostasis, energy metabolism, antioxidant defenses and the anti-inflammatory response. Recently, our group characterized cortical astrocyte cultures from adult Wistar rats. In line with that work, we studied glial function using an experimental in vitro model of aging astrocytes (30 days in vitro after reaching confluence) from newborn (NB), adult (AD) and aged (AG) Wistar rats. We evaluated metabolic parameters, such as the glucose uptake, glutamine synthetase (GS) activity, and glutathione (GSH) content, as well as the GFAP, GLUT-1 and xCT expression. AD and AG astrocytes take up less glucose than NB astrocytes and had decreased GLUT1 expression levels. Furthermore, AD and AG astrocytes exhibited decreased GS activity compared to NB cells. Simultaneously, AD and AG astrocytes showed an increase in GSH levels, along with an increase in xCT expression. NB, AD and AG astrocytes presented similar morphology; however, differences in GFAP levels were observed. Taken together, these results improve the knowledge of cerebral senescence and represent an innovative tool for brain studies of aging. PMID:26210720

  2. Serotonin axons of the neostriatum show a higher affinity for striatal than for ventral mesencephalic transplants: a quantitative study in adult and immature recipient rats.

    PubMed

    Pierret, P; Vallée, A; Bosler, O; Dorais, M; Moukhles, H; Abbaszadeh, R; Lepage, Y; Doucet, G

    1998-07-01

    We previously showed that grafts of fetal ventral mesencephalic tissue are practically not innervated by host serotonin (5-HT) axons after implantation into the striatum of rats aged more than 14 days, at variance with transplants of cortical or striatal tissue into the adult striatum, which are well innervated by these axons. Using 5-HT immunohistochemistry and in vitro [3H]5-HT uptake/autoradiography, we have examined and quantified the innervation of ventral mesencephalic versus striatal grafts several months after implantation into the striatum of neonatal (postnatal day 5 or P5), juvenile (P15), and adult rats. Ventral mesencephalic grafts implanted in P5 rats received a moderate 5-HT innervation, while similar grafts implanted in P15 or adult recipients were almost free of any 5-HT fibers (-80%, compared to P5). The density of 5-HT innervation showed a tendency toward higher values in striatal than in ventral mesencephalic grafts (1.6-2 times higher in P5 and adult recipients; 4 times higher in P15 recipients). The difference was more striking, and significant, when only the true striatal portions of the striatal grafts were considered, i.e., DARPP-32-immunopositive areas (4-5 times higher in P5 and adult recipients; 10 times higher in P15 recipients). Accordingly, these DARPP-32-positive areas were also more densely innervated than the DARPP-32-negative zones of the same grafts (3 times higher at any age). The 5-HT innervation density also decreased with increasing age of the recipients in DARPP-32-positive, as well as DARPP-32-negative compartments of the striatal grafts (-75% in adults), but this decrease appeared more gradual (-50% in juveniles) than with mesencephalic grafts. It is concluded that the 5-HT axons innervating the neostriatum have a better affinity for striatal grafts than for ventral mesencephalic grafts or the nonstriatal portions of striatal grafts. In adulthood, the relative affinity of these axons for the different types of grafts is

  3. In utero/lactational and adult exposures to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) show differential effects on craniofacial development and growth in rats.

    PubMed

    Sholts, Sabrina B; Korkalainen, Merja; Simanainen, Ulla; Miettinen, Hanna M; Håkansson, Helen; Viluksela, Matti

    2015-11-01

    In a previous study of female Han/Wistar (H/W) and Long-Evans (L-E) rats, we found that adult exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) was associated with size decreases in the cranium and especially the face. In this study we compared these crania to those from male and female Sprague-Dawley (S-D) rats with in utero/lactational exposure to TCDD, using morphometric variables of size, shape, and fluctuating asymmetry to quantify the effects of dose on craniofacial development and growth. At the highest levels of exposure, in utero/lactational and adult TCDD exposures both resulted in small but significant reductions in facial size parameters (i.e., 3-5%) in only females and minor effects on facial shape in both sexes. The shape effects of in utero/lactational exposure were most significant at the sutural intersections, whereas adult exposure to TCDD corresponded to dose-dependent changes of decreasing facial length and vault breadth. Fluctuating asymmetry in general explained a relatively small amount of shape variation compared with other effects, and only increased significantly in female L-E rats with high levels of adult exposure to TCDD. These results indicate that TCDD-related changes in cranial development and growth in rats can vary with the timing and duration of exposure, and with sex. Further investigations of other dioxin-like compounds and animal species will broaden our understanding of how chemicals exposure can influence the development and growth of the mammalian skeleton.

  4. Investigation of infectivity of neonates and adults from different rat strains to Toxoplasma gondii Prugniaud shows both variation which correlates with iNOS and Arginase-1 activity and increased susceptibility of neonates to infection.

    PubMed

    Gao, Jiang-Mei; Yi, Si-Qi; Wu, Ming-Shui; Geng, Guo-Qing; Shen, Ji-Long; Lu, Fang-Li; Hide, Geoff; Lai, De-Hua; Lun, Zhao-Rong

    2015-02-01

    Mouse models differ considerably from humans with regard to clinical symptoms of toxoplasmosis caused by Toxoplasma gondii and, by comparison, the rat model is more representative of this disease in humans. In the present study, we found that different strains of adult and newborn rats (Lewis, Wistar, Sprague Dawley, Brown Norway and Fischer 344) exhibited remarkable variation in the number of brain cysts following inoculation with the T.gondii Prugniaud strain. In adult rats, large numbers of cysts (1231 ± 165.6) were observed in Fischer 344, but none in the other four. This situation was different in newborn rats aged from 5 to 20 days old. All Fischer 344 and Brown Norway newborns were cyst-positive while cyst-positive infection in Sprague Dawley neonates ranged from 54.5% to 60% depending on their age at infection. In Wistar and Lewis rat neonates, however, cyst-positivity rates of 0-42.9% and 0-25% were found respectively. To investigate whether rat strain differences in infectivity could be related to inherent strain and genetic differences in the host immune response, we correlated our data with previously reported strain differences in iNOS/Arginase ratio in adult rats and found them to be linked. These results show that interactions between host genetic background and age of rat influence T.gondii infection.

  5. A novel underuse model shows that inactivity but not ovariectomy determines the deteriorated material properties and geometry of cortical bone in the tibia of adult rats.

    PubMed

    Miyagawa, Kazuaki; Kozai, Yusuke; Ito, Yumi; Furuhama, Takami; Naruse, Kouji; Nonaka, Kiichi; Nagai, Yumiko; Yamato, Hideyuki; Kashima, Isamu; Ohya, Keiichi; Aoki, Kazuhiro; Mikuni-Takagaki, Yuko

    2011-07-01

    Our goal in this study was to determine to what extent the physiologic consequences of ovariectomy (OVX) in bones are exacerbated by a lack of daily activity such as walking. We forced 14-week-old female rats to be inactive for 15 weeks with a unique experimental system that prevents standing and walking while allowing other movements. Tibiae, femora, and 4th lumbar vertebrae were analyzed by peripheral quantitative computed tomography (pQCT), microfocused X-ray computed tomography (micro-CT), histology, histomorphometry, Raman spectroscopy, and the three-point bending test. Contrary to our expectation, the exacerbation was very much limited to the cancellous bone parameters. Parameters of femur and tibia cortical bone were affected by the forced inactivity but not by OVX: (1) cross-sectional moment of inertia was significantly smaller in Sham-Inactive rat bones than that of their walking counterparts; (2) the number of sclerostin-positive osteocytes per unit cross-sectional area was larger in Sham-Inactive rat bones than in Sham-Walking rat bones; and (3) material properties such as ultimate stress of inactive rat tibia was lower than that of their walking counterparts. Of note, the additive effect of inactivity and OVX was seen only in a few parameters, such as the cancellous bone mineral density of the lumbar vertebrae and the structural parameters of cancellous bone in the lumbar vertebrae/tibiae. It is concluded that the lack of daily activity is detrimental to the strength and quality of cortical bone in the femur and tibia of rats, while lack of estrogen is not. Our inactive rat model, with the older rats, will aid the study of postmenopausal osteoporosis, the etiology of which may be both hormonal and mechanical. PMID:21127921

  6. Rats show only a weak preference for the artificial sweetener aspartame.

    PubMed

    Sclafani, A; Abrams, M

    1986-01-01

    The preference of adult female rats for aspartame (L-asparty L-phenylalamine methyl ester) was measured using 24 hr/day and 30 min/day two bottle preference tests. At aspartame concentrations that humans find sweet (0.0125% to 0.05%) the rats failed to prefer aspartame to water. At higher concentrations (0.1% to 1.0%) half (n = 11) of the rats tested displayed mild (64%) to moderate (83%) aspartame preferences. The other half of the rats were indifferent or avoided the aspartame. Even at the most preferred concentration (1.0%) the rats' aspartame preference was much less than their preference for saccharin or sucrose, and they showed little increase in total fluid intake when given the aspartame solution. The results indicate that aspartame is not very palatable to rats, and suggest that it has little or no sweet, i.e., sucrose-like, taste to rats as it does to humans.

  7. Sugar-dependent rats show enhanced intake of unsweetened ethanol.

    PubMed

    Avena, Nicole M; Carrillo, Carmen A; Needham, Lance; Leibowitz, Sarah F; Hoebel, Bartley G

    2004-01-01

    Rats show signs of dependence on sugar when it is available intermittently, including bingeing, withdrawal, and cross-sensitization with amphetamine. In the current study, we sought to determine whether sugar-dependent rats would show increased intake of unsweetened ethanol and, conversely, whether intermittent access to ethanol would augment sugar consumption. In Experiment 1, with intermittent versus ad libitum access to ethanol, Sprague-Dawley rats were given escalating concentrations of ethanol (1%, 2%, 4%, 7%, and 9%) over the course of 20 days. Rats in the intermittent ethanol access group, with 12-h daily access, consumed more 4%, 7%, and 9% ethanol during the first hour of access, and more 9% ethanol daily, than did rats in the ad libitum ethanol access group. In Experiment 2, with ethanol as a gateway to sugar intake, the rats from Experiment 1 were switched to 10% sucrose with 12-h daily access for 1 week. Rats in the intermittent ethanol access group consumed significantly more sugar than was consumed by rats in a control group with no prior ethanol experience. In Experiment 3, with sugar as a gateway to ethanol to determine whether sugar dependence leads to increased ethanol intake, four groups were maintained for 21 days according to the following designations: intermittent access to sugar and chow, ad libitum access to sugar and chow, intermittent access to chow, or ad libitum access to chow. Four days later, all groups were switched to intermittent ethanol access, as described in Experiment 1. The group with intermittent access to sugar and chow consumed the most 9% ethanol, supporting the suggestion that sugar dependence alters a rat's proclivity to drink ethanol. These results may relate to the co-morbidity between binge-eating disorders and alcohol intake and the tendency of people abstaining from alcohol to consume excessive amounts of sugar. In conclusion, bingeing on either ethanol or sugar fosters intake of the other.

  8. Aged rats show dominant modulation of lower frequency hippocampal theta rhythm during running.

    PubMed

    Li, Jia-Yi; Kuo, Terry B J; Yang, Cheryl C H

    2016-10-01

    Aging causes considerable decline in both physiological and mental functions, particularly cognitive function. The hippocampal theta rhythm (4-12Hz) is related to both cognition and locomotion. Aging-related findings of the frequency and amplitude of hippocampal theta oscillations are inconsistent and occasionally contradictory. This inconsistency may be due to the effects of the sleep/wake state and different frequency subbands being overlooked. We assumed that aged rats have lower responses of the hippocampal theta rhythm during running, which is mainly due to the dominant modulation of theta frequency subbands related to cognition. By simultaneously recording electroencephalography, physical activity (PA), and the heart rate (HR), this experiment explored the theta oscillations before, during, and after treadmill running at a constant speed in 8-week-old (adult) and 60-week-old (middle-aged) rats. Compared with adult rats, the middle-aged rats exhibited lower theta activity in all frequency ranges before running. Running increased the theta frequency (Frq, 4-12Hz), total activity of the whole theta band (total power, TP), activity of the middle theta frequency (MT, 6.5-9.5Hz), and PA in both age groups. However, the middle-aged rats still showed fewer changes in these parameters during the whole running process. After the waking baseline values were substracted, middle-aged rats showed significantly fewer differences in ΔFrq, ΔTP, and ΔMT but significantly more differences in low-frequency theta activity (4.0-6.5Hz) and HR than the adult rats did. Therefore, the decreasing activity and response of the whole theta band in the middle-aged rats resulted in dominant modulation of the middle to lower frequency (4.0-9.5Hz) theta rhythm. The different alterations in the theta rhythm during treadmill running in the two groups may reflect that learning decline with age.

  9. Aged rats show dominant modulation of lower frequency hippocampal theta rhythm during running.

    PubMed

    Li, Jia-Yi; Kuo, Terry B J; Yang, Cheryl C H

    2016-10-01

    Aging causes considerable decline in both physiological and mental functions, particularly cognitive function. The hippocampal theta rhythm (4-12Hz) is related to both cognition and locomotion. Aging-related findings of the frequency and amplitude of hippocampal theta oscillations are inconsistent and occasionally contradictory. This inconsistency may be due to the effects of the sleep/wake state and different frequency subbands being overlooked. We assumed that aged rats have lower responses of the hippocampal theta rhythm during running, which is mainly due to the dominant modulation of theta frequency subbands related to cognition. By simultaneously recording electroencephalography, physical activity (PA), and the heart rate (HR), this experiment explored the theta oscillations before, during, and after treadmill running at a constant speed in 8-week-old (adult) and 60-week-old (middle-aged) rats. Compared with adult rats, the middle-aged rats exhibited lower theta activity in all frequency ranges before running. Running increased the theta frequency (Frq, 4-12Hz), total activity of the whole theta band (total power, TP), activity of the middle theta frequency (MT, 6.5-9.5Hz), and PA in both age groups. However, the middle-aged rats still showed fewer changes in these parameters during the whole running process. After the waking baseline values were substracted, middle-aged rats showed significantly fewer differences in ΔFrq, ΔTP, and ΔMT but significantly more differences in low-frequency theta activity (4.0-6.5Hz) and HR than the adult rats did. Therefore, the decreasing activity and response of the whole theta band in the middle-aged rats resulted in dominant modulation of the middle to lower frequency (4.0-9.5Hz) theta rhythm. The different alterations in the theta rhythm during treadmill running in the two groups may reflect that learning decline with age. PMID:27496645

  10. A Transgenic Rat for Specifically Inhibiting Adult Neurogenesis123

    PubMed Central

    Grigereit, Laura; Pickel, James

    2016-01-01

    Abstract The growth of research on adult neurogenesis and the development of new models and tools have greatly advanced our understanding of the function of newborn neurons in recent years. However, there are still significant limitations in the ability to identify the functions of adult neurogenesis in available models. Here we report a transgenic rat (TK rat) that expresses herpes simplex virus thymidine kinase in GFAP+ cells. Upon treating TK rats with the antiviral drug valganciclovir, granule cell neurogenesis can be completely inhibited in adulthood, in both the hippocampus and olfactory bulb. Interestingly, neurogenesis in the glomerular and external plexiform layers of the olfactory bulb was only partially inhibited, suggesting that some adult-born neurons in these regions derive from a distinct precursor population that does not express GFAP. Within the hippocampus, blockade of neurogenesis was rapid and nearly complete within 1 week of starting treatment. Preliminary behavioral analyses indicate that general anxiety levels and patterns of exploration are generally unaffected in neurogenesis-deficient rats. However, neurogenesis-deficient TK rats showed reduced sucrose preference, suggesting deficits in reward-related behaviors. We expect that TK rats will facilitate structural, physiological, and behavioral studies that complement those possible in existing models, broadly enhancing understanding of the function of adult neurogenesis. PMID:27257630

  11. Leptin inhibits testosterone secretion from adult rat testis in vitro.

    PubMed

    Tena-Sempere, M; Pinilla, L; González, L C; Diéguez, C; Casanueva, F F; Aguilar, E

    1999-05-01

    adult rats. In addition, 10(-9) M leptin inhibited LH and FSH secretion by incubated hemi-pituitaries from fasted adult males, whereas, at all doses tested, it was ineffective in modulating PRL release. Our results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level. Furthermore, the present data suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis.

  12. Leptin inhibits testosterone secretion from adult rat testis in vitro.

    PubMed

    Tena-Sempere, M; Pinilla, L; González, L C; Diéguez, C; Casanueva, F F; Aguilar, E

    1999-05-01

    adult rats. In addition, 10(-9) M leptin inhibited LH and FSH secretion by incubated hemi-pituitaries from fasted adult males, whereas, at all doses tested, it was ineffective in modulating PRL release. Our results show that leptin, depending on the state of sexual maturation, is able to inhibit testosterone secretion acting at the testicular level. Furthermore, the present data suggest that the actions of leptin on the reproductive system are complex and are probably carried out at different levels of the hypothalamic-pituitary-gonadal axis. PMID:10320818

  13. Toxicity of zinc oxide nanoparticles on adult male Wistar rats.

    PubMed

    Abbasalipourkabir, Roghayeh; Moradi, Hemen; Zarei, Sadegh; Asadi, Soheila; Salehzadeh, Aref; Ghafourikhosroshahi, Abolfazl; Mortazavi, Motahareh; Ziamajidi, Nasrin

    2015-10-01

    The purpose of this study was to investigate the effects of zinc oxide nanoparticles (nZnO) on adult male Wistar rats. Thirty male Wistar rats divided into five groups of six animals each were used for this study. For ten days, Groups one to four continuously received 50, 100, 150 and 200 mg/kg nZnO, respectively. Group five served as the control group. At the end of the study, the rats were sacrificed and histopathological study of the liver and renal tissue, sperm analysis, serum oxidative stress parameters and some liver enzymes were done. The results of this study showed that nZnO at concentration more than 50 mg/kg lead to significant changes in liver enzymes, oxidative stress, liver and renal tissue and sperm quality and quantity. In conclusion, the toxicity of nZnO is more significant when the concentration is increased; however, the use of low doses requires further investigation.

  14. Interactions between respiratory oscillators in adult rats

    PubMed Central

    Huckstepp, Robert TR; Henderson, Lauren E; Cardoza, Kathryn P; Feldman, Jack L

    2016-01-01

    Breathing in mammals is hypothesized to result from the interaction of two distinct oscillators: the preBötzinger Complex (preBötC) driving inspiration and the lateral parafacial region (pFL) driving active expiration. To understand the interactions between these oscillators, we independently altered their excitability in spontaneously breathing vagotomized urethane-anesthetized adult rats. Hyperpolarizing preBötC neurons decreased inspiratory activity and initiated active expiration, ultimately progressing to apnea, i.e., cessation of both inspiration and active expiration. Depolarizing pFL neurons produced active expiration at rest, but not when inspiratory activity was suppressed by hyperpolarizing preBötC neurons. We conclude that in anesthetized adult rats active expiration is driven by the pFL but requires an additional form of network excitation, i.e., ongoing rhythmic preBötC activity sufficient to drive inspiratory motor output or increased chemosensory drive. The organization of this coupled oscillator system, which is essential for life, may have implications for other neural networks that contain multiple rhythm/pattern generators. DOI: http://dx.doi.org/10.7554/eLife.14203.001 PMID:27300271

  15. Contextual fear conditioning differs for infant, adolescent, and adult rats.

    PubMed

    Esmorís-Arranz, Francisco J; Méndez, Cástor; Spear, Norman E

    2008-07-01

    Contextual fear conditioning was tested in infant, adolescent, and adult rats in terms of Pavlovian-conditioned suppression. When a discrete auditory-conditioned stimulus (CS) was paired with footshock (unconditioned stimulus, US) within the largely olfactory context, infants and adolescents conditioned to the context with substantial effectiveness, but adult rats did not. When unpaired presentations of the CS and US occurred within the context, contextual fear conditioning was strong for adults, weak for infants, but about as strong for adolescents as when pairings of CS and US occurred in the context. Nonreinforced presentations of either the CS or context markedly reduced contextual fear conditioning in infants, but, in adolescents, CS extinction had no effect on contextual fear conditioning, although context extinction significantly reduced it. Neither CS extinction nor context extinction affected responding to the CS-context compound in infants, suggesting striking discrimination between the compound and its components. Female adolescents showed the same lack of effect of component extinction on response to the compound as infants, but CS extinction reduced responding to the compound in adolescent males, a sex difference seen also in adults. Theoretical implications are discussed for the development of perceptual-cognitive processing and hippocampus role.

  16. Differences between brainstem gliomas in juvenile and adult rats

    PubMed Central

    WANG, YU; TIAN, YONGJI; WAN, HONG; LI, DEZHI; WU, WENHAO; YIN, LUXIN; JIANG, JIAN; WAN, WEIQING; ZHANG, LIWEI

    2013-01-01

    Clinical studies have shown that gliomas of the brainstem behave differently in children and adults. The aim of the present study was to compare and analyze the differences between these gliomas in juvenile and adult rats with regard to tumor growth, survival, pathology and magnetic resonance imaging (MRI). A total of 25 juvenile and 25 adult Wistar rats were divided into groups A (15 juvenile rats), B (10 juvenile rats), C (15 adult rats) and D (10 adult rats). The rats of groups A and C (experimental) were injected with glioma cells, while groups B and D (control) were injected with a physiological saline solution. Rat neurological signs, survival time, tumor size, hematoxylin and eosin (HE) staining and immunohistochemical staining for MMP-2, MMP-9 and β-catenin were compared. The survival time of group A was 19.47±2.232 days, whereas that of group C was 21.47±2.232 days (P<0.05). The tumor sizes were 4.55 and 4.62 mm (P>0.05) in groups A and C, respectively. HE and immunohistochemical staining revealed no differences between the groups. The results suggest that the growth patterns and invasiveness of brainstem gliomas may vary in children compared with adults due to the varied biological behaviors of the tumor cells. PMID:23946812

  17. Slc:Wistar outbred rats show close genetic similarity with F344 inbred rats.

    PubMed

    Nakanishi, Satoshi; Serikawa, Tadao; Kuramoto, Takashi

    2015-01-01

    Although Slc:Wistar rats are used widely in biomedical research as outbred rats, close similarities in growth curves, survival rates, and immunological and biochemical phenotypes have been reported between Slc:Wistar and F344 inbred rats. We reported previously that nine genetic variations that were fixed in Slc:Wistar rats had identical genotypes in F344 rats. Here, we examined the genetic characteristics of Slc:Wistar rats using 27 simple-sequence length polymorphism (SSLP) markers and compared them with other Wistar stocks available in Japan and with some F344 strains. Among 27 SSLP loci, 23 (85%) were fixed in the Slc:Wistar rats, which was the highest among the other Wistar stocks. The 23 fixed loci shared identical genotypes with corresponding loci in F344 rats. Further, the predominant allele types in the unfixed loci had allele frequencies as high as 80%, and these alleles were identical in the F344 rats. When the nine genetic variations reported previously are added, a total of 32 (89%) out of the 36 loci examined were fixed and identical in the Slc:Wistar and F344 rat genomes. These findings indicate the low genetic variation in Slc:Wistar rats and the high genetic similarity between the Slc:Wistar and F344 inbred rats. This study demonstrates the importance of characterizing outbred rats and the need to pay ample attention to the genetic characteristics the Slc:Wistar rats for their proper use.

  18. Preproglucagon mRNA expression in adult rat submandibular glands.

    PubMed

    Egéa, J C; Hirtz, C; Deville de Périère, D

    2003-04-01

    Salivary glands of various animal species have been reported to contain and suggested to produce glucagon or glucagon-like material, but the origin and the nature of this salivary peptide are still doubtful. The present study was undertaken to ascertain whether the glucagon gene is expressed in rat submandibular glands and in an immortalized murine cell line derived from salivary glands (SCA-9 cell line). For this purpose, total RNA was isolated from submandibular glands or cultured cells and submitted to reverse transcription. The cDNAs obtained were amplified by a nested polymerase chain reaction using preproglucagon primers. The results showed that the preproglucagon mRNA was expressed in adult rat submandibular glands but not in the SCA-9 cell line. Determination of cyclic DNA (cDNA) sequence established identity with the coding regions of rat pancreatic pre-proglucagon gene. In conclusion, these results strongly support the idea that rat submandibular glands could represent a source of extrapancreatic glucagon or of its precursor's peptide.

  19. Mechanically induced orientation of adult rat cardiac myocytes in vitro

    NASA Technical Reports Server (NTRS)

    Samuel, J.-L.; Vandenburgh, H. H.

    1990-01-01

    The present study describes the spatial orientation of a population of freshly isolated adult rat cardiac myocytes using a computerized mechanical cell stimulator device for tissue cultured cells. A continuous unidirectional stretch of the substratum at 60 to 400 microns/min for 120 to 30 min, respectively, during the cell attachment period in a serum-free medium was found to induce a significant threefold increase in the number of rod-shaped myocytes oriented parallel to the direction of movement. The myocytes orient less well with unidirectional substratum stretching after their adhesion to the substratum. Adult myocytes plated onto a substratum undergoing continuous 10-percent stretch-relaxation cycling show no significant change in the myocyte orientation or cytoskeletal organization. In addition to the type of mechanical activity, orientation of rod-shaped myocytes is dependent on the speed of the substratum, the final stretch amplitude, and the timing between initiation of substratum stretching and adhesion of myocytes to the substratum.

  20. Leucocyte responses to fighting in the adult male bandicoot rat.

    PubMed

    Ghosh, P R; Sahu, A; Maiti, B R

    1983-01-01

    The effect of fighting stress on blood leucocyte count was studied in the adult male bandicoot rat. Exposure to fighting stress for 3 h induced neutrophilia, eosinopenia, lymphopenia and monocytopenia. The changes were more significant in the subordinate rat than in the dominant animal. It is suggested that leucocyte responses to fighting are perhaps mediated by the adrenal gland in these animals.

  1. Obesity-resistant S5B rats showed great cocaine conditioned place preference than the obesity-prone OM rats

    SciTech Connect

    Thanos, P.K.; Wang, G.; Thanos, P.K..; Kim, R.; Cho, J.; Michaelides, M.; Anderson, B.J.; Primeaux, S.D.; Bray, G.A.; Wang, G.-J.; Robinson, J.K.; Volkow, N.D.

    2010-12-01

    Dopamine (DA) and the DA D2 receptor (D2R) are involved in the rewarding and conditioned responses to food and drug rewards. Osborne-Mendel (OM) rats are genetically prone and S5B/P rats are genetically resistant to obesity when fed a high-fat diet. We hypothesized that the differential sensitivity of these two rat strains to natural rewards may also be reflected in sensitivity to drugs of abuse. Therefore, we tested whether OM and S5B/P rats showed a differential preference to cocaine using conditioned place preference (CPP). To also evaluate whether there is specific involvement of the D2R in this differential conditioning sensitivity, we then tested whether the D2R agonist bromocriptine (BC) would differentially affect the effects of cocaine in the two strains. OM and S5B/P rats were conditioned with cocaine (5 or 10 mg/kg) in one chamber and saline in another for 8 days. Rats were then tested for cocaine preference. The effects of BC (0.5, 1, 5, 10, 20 mg/kg) on cocaine preference were then assessed in subsequent test sessions. OM rats did not show a significant preference for the cocaine-paired chamber on test day. Only the S5B/P rats showed cocaine CPP. Later treatment with only the highest dose of BC resulted in reduced cocaine CPP in S5B/P rats when treated with 5 mg/kg cocaine and in OM rats treated with 10 mg/kg cocaine. Our results indicated that obesity-resistant S5B rats showed greater cocaine CPP than the obesity-prone OM rats. These findings do not support a theory of common vulnerability for reinforcer preferences (food and cocaine). However, they show that BC reduced cocaine conditioning effects supporting at least a partial regulatory role of D2R in conditioned responses to drugs.

  2. Decline of taste sensitivity in protein deficient adult rats.

    PubMed

    Ohara, I; Tabuchi, R; Kimura, M; Itokawa, Y

    1995-05-01

    The influence of dietary protein levels on taste sensitivity was studied in adult rats. Low protein diets of 0.0, 2.5, or 5.0% purified egg protein (PEP) were fed to animals for 28 days. Two bottle choice preference tests between aqueous solutions of either 2, 9, 17, or 86 mM sodium chloride and deionized water were conducted in an ascending order on days 14, 16, 18, and 20. Urine samples were collected for zinc and creatinine analysis. Blood samples were also collected for measuring serum zinc and creatinine concentrations. Scanning electron microscopy was performed to observe rats' tongue epithelia. Protein free diet group showed significantly lower taste sensitivity and renal reabsorption rate than other protein containing diet groups, while serum zinc and creatinine concentrations, and creatinine clearance were not affected by dietary protein level. Degeneration of filiform papillae and imperforation of taste pore of fungiform papillae were observed in protein free diet group. This experiment implies at least 2.5% dietary protein is required to manifest normal taste function in the adult. PMID:7610145

  3. Decline of taste sensitivity in protein deficient adult rats.

    PubMed

    Ohara, I; Tabuchi, R; Kimura, M; Itokawa, Y

    1995-05-01

    The influence of dietary protein levels on taste sensitivity was studied in adult rats. Low protein diets of 0.0, 2.5, or 5.0% purified egg protein (PEP) were fed to animals for 28 days. Two bottle choice preference tests between aqueous solutions of either 2, 9, 17, or 86 mM sodium chloride and deionized water were conducted in an ascending order on days 14, 16, 18, and 20. Urine samples were collected for zinc and creatinine analysis. Blood samples were also collected for measuring serum zinc and creatinine concentrations. Scanning electron microscopy was performed to observe rats' tongue epithelia. Protein free diet group showed significantly lower taste sensitivity and renal reabsorption rate than other protein containing diet groups, while serum zinc and creatinine concentrations, and creatinine clearance were not affected by dietary protein level. Degeneration of filiform papillae and imperforation of taste pore of fungiform papillae were observed in protein free diet group. This experiment implies at least 2.5% dietary protein is required to manifest normal taste function in the adult.

  4. Differential Effects of Acute Alcohol on EEG and Sedative Responses in Adolescent and Adult Wistar Rats

    PubMed Central

    Pian, Jerry P.; Criado, Jose R.; Walker, Brendan M.; Ehlers, Cindy L.

    2008-01-01

    Age-related developmental differences in sensitivity to the acute effects of alcohol may play an important role in the development of alcoholism. The present study was designed to evaluate the acute effects of alcohol on cortical electroencephalogram (EEG) in adolescent (P36) and adult (P78) Wistar rats. Five minutes of EEG was recorded after administration of 0, 0.75 or 1.5 g/kg alcohol. The righting reflex was performed to measure the sedative effects of alcohol (3.5 g/kg) and total sleeping time for each rat. Our results showed that alcohol (1.5 g/kg) increased power in the 1–2 Hz band and decreased the power in the 32–50 Hz band in the parietal cortical region of adolescent rats. Alcohol (1.5 g/kg) also increased stability of the EEG power in the slow-wave frequency bands (2–4 Hz, 4–6 Hz, and 6–8 Hz) of adolescent rats. In the frontal cortex of adult rats, but not in adolescent rats, alcohol (1.5 or 0.75 g/kg) decreased the power in the 16–32 Hz frequency band. Alcohol (1.5 g/kg) differentially increased power in a multiple of slow-wave frequency bands (2–4 Hz and 4–6 Hz) in the parietal cortex of adult rats as compared to adolescent rats. Adolescent rats were shown significantly shorter sleeping time and higher blood alcohol levels after regaining reflex than adult rats. Our results provide additional evidence of age-related differences in the effects of acute alcohol on cortical EEG, sedation and tolerance. PMID:18191821

  5. Expression of Lymphatic Markers in the Adult Rat Spinal Cord

    PubMed Central

    Kaser-Eichberger, Alexandra; Schroedl, Falk; Bieler, Lara; Trost, Andrea; Bogner, Barbara; Runge, Christian; Tempfer, Herbert; Zaunmair, Pia; Kreutzer, Christina; Traweger, Andreas; Reitsamer, Herbert A.; Couillard-Despres, Sebastien

    2016-01-01

    Under physiological conditions, lymphatic vessels are thought to be absent from the central nervous system (CNS), although they are widely distributed within the rest of the body. Recent work in the eye, i.e., another organ regarded as alymphatic, revealed numerous cells expressing lymphatic markers. As the latter can be involved in the response to pathological conditions, we addressed the presence of cells expressing lymphatic markers within the spinal cord by immunohistochemistry. Spinal cord of young adult Fisher rats was scrutinized for the co-expression of the lymphatic markers PROX1 and LYVE-1 with the cell type markers Iba1, CD68, PGP9.5, OLIG2. Rat skin served as positive control for the lymphatic markers. PROX1-immunoreactivity was detected in many nuclei throughout the spinal cord white and gray matter. These nuclei showed no association with LYVE-1. Expression of LYVE-1 could only be detected in cells at the spinal cord surface and in cells closely associated with blood vessels. These cells were found to co-express Iba1, a macrophage and microglia marker. Further, double labeling experiments using CD68, another marker found in microglia and macrophages, also displayed co-localization in the Iba1+ cells located at the spinal cord surface and those apposed to blood vessels. On the other hand, PROX1-expressing cells found in the parenchyma were lacking Iba1 or PGP9.5, but a significant fraction of those cells showed co-expression of the oligodendrocyte lineage marker OLIG2. Intriguingly, following spinal cord injury, LYVE-1-expressing cells assembled and reorganized into putative pre-vessel structures. As expected, the rat skin used as positive controls revealed classical lymphatic vessels, displaying PROX1+ nuclei surrounded by LYVE-1-immunoreactivity. Classical lymphatics were not detected in adult rat spinal cord. Nevertheless, numerous cells expressing either LYVE-1 or PROX1 were identified. Based on their localization and overlapping expression with

  6. Expression of Lymphatic Markers in the Adult Rat Spinal Cord.

    PubMed

    Kaser-Eichberger, Alexandra; Schroedl, Falk; Bieler, Lara; Trost, Andrea; Bogner, Barbara; Runge, Christian; Tempfer, Herbert; Zaunmair, Pia; Kreutzer, Christina; Traweger, Andreas; Reitsamer, Herbert A; Couillard-Despres, Sebastien

    2016-01-01

    Under physiological conditions, lymphatic vessels are thought to be absent from the central nervous system (CNS), although they are widely distributed within the rest of the body. Recent work in the eye, i.e., another organ regarded as alymphatic, revealed numerous cells expressing lymphatic markers. As the latter can be involved in the response to pathological conditions, we addressed the presence of cells expressing lymphatic markers within the spinal cord by immunohistochemistry. Spinal cord of young adult Fisher rats was scrutinized for the co-expression of the lymphatic markers PROX1 and LYVE-1 with the cell type markers Iba1, CD68, PGP9.5, OLIG2. Rat skin served as positive control for the lymphatic markers. PROX1-immunoreactivity was detected in many nuclei throughout the spinal cord white and gray matter. These nuclei showed no association with LYVE-1. Expression of LYVE-1 could only be detected in cells at the spinal cord surface and in cells closely associated with blood vessels. These cells were found to co-express Iba1, a macrophage and microglia marker. Further, double labeling experiments using CD68, another marker found in microglia and macrophages, also displayed co-localization in the Iba1+ cells located at the spinal cord surface and those apposed to blood vessels. On the other hand, PROX1-expressing cells found in the parenchyma were lacking Iba1 or PGP9.5, but a significant fraction of those cells showed co-expression of the oligodendrocyte lineage marker OLIG2. Intriguingly, following spinal cord injury, LYVE-1-expressing cells assembled and reorganized into putative pre-vessel structures. As expected, the rat skin used as positive controls revealed classical lymphatic vessels, displaying PROX1+ nuclei surrounded by LYVE-1-immunoreactivity. Classical lymphatics were not detected in adult rat spinal cord. Nevertheless, numerous cells expressing either LYVE-1 or PROX1 were identified. Based on their localization and overlapping expression with

  7. Male Roman high and low avoidance rats show different patterns of copulatory behaviour: comparison with Sprague Dawley rats.

    PubMed

    Sanna, Fabrizio; Corda, Maria Giuseppa; Melis, Maria Rosaria; Piludu, Maria Antonietta; Giorgi, Osvaldo; Argiolas, Antonio

    2014-03-29

    Roman high- (RHA) and low-avoidance (RLA) rats, selectively bred for, respectively, rapid vs. extremely poor acquisition of avoidant behaviour in the shuttle-box, display different coping strategies when exposed to aversive environmental conditions: RLA rats are reactive copers and show hyperemotional behaviour characterized by hypomotility and freezing, while RHA rats show a proactive coping behaviour aimed at gaining control over the stressor. RHA rats also display a robust sensation/novelty seeking profile, high baseline levels of impulsivity, and marked preference for, and intake of, natural and drug rewards. This study shows that the Roman lines also differ in sexual behaviour, a main source of natural reward. Thus, male RHA rats engaged in copulatory activity with a receptive female showing more mounts, intromissions and ejaculations in the first copulation test as compared with their RLA counterparts and Sprague Dawley rats used as an external reference strain. Such differences decreased only partially in subsequent copulation tests, with RHA rats always showing higher levels of sexual motivation and performance than RLA rats. Accordingly, analysis of copulatory parameters of five copulation tests performed at 3-day intervals confirmed that the Roman lines display different patterns of copulatory activity that persist after stabilization of copulatory behaviour by sexual experience. Finally, the weight of the testes, epididymides and seminal vesicles increased to a similar extent in both Roman lines after sexual activity. These results are discussed in terms of the relative contribution of differences in brain neurotransmission (mainly dopamine) and neuroendocrine function to the different patterns of copulatory behaviour of the Roman lines.

  8. Physiological responses during whole body suspension of adult rats

    NASA Technical Reports Server (NTRS)

    Steffen, J. M.; Fell, R. D.; Musacchia, X. J.

    1987-01-01

    The objective of this study was to characterize responses of adult rats to one and two weeks of whole body suspension. Body weights and food and water intakes were initially reduced during suspension, but, while intake of food and water returned to presuspension levels, body weight remained depressed. Diuresis was evident, but only during week two. Hindlimb muscle responses were differential, with the soleus exhibiting the greatest atrophy and the EDL a relative hypertrophy. These findings suggest that adult rats respond qualitatively in a manner similar to juveniles during suspension.

  9. Prenatal choline availability alters the context sensitivity of Pavlovian conditioning in adult rats.

    PubMed

    Lamoureux, Jeffrey A; Meck, Warren H; Williams, Christina L

    2008-12-01

    The effects of prenatal choline availability on Pavlovian conditioning were assessed in adult male rats (3-4 mo). Neither supplementation nor deprivation of prenatal choline affected the acquisition and extinction of simple Pavlovian conditioned excitation, or the acquisition and retardation of conditioned inhibition. However, prenatal choline availability significantly altered the contextual control of these learned behaviors. Both control and choline-deprived rats exhibited context specificity of conditioned excitation as exhibited by a loss in responding when tested in an alternate context after conditioning; in contrast, choline-supplemented rats showed no such effect. When switched to a different context following extinction, however, both choline-supplemented and control rats showed substantial contextual control of responding, whereas choline-deficient rats did not. These data support the view that configural associations that rely on hippocampal function are selectively sensitive to prenatal manipulations of dietary choline during prenatal development.

  10. Prenatal choline availability alters the context sensitivity of Pavlovian conditioning in adult rats

    PubMed Central

    Lamoureux, Jeffrey A.; Meck, Warren H.; Williams, Christina L.

    2008-01-01

    The effects of prenatal choline availability on Pavlovian conditioning were assessed in adult male rats (3–4 mo). Neither supplementation nor deprivation of prenatal choline affected the acquisition and extinction of simple Pavlovian conditioned excitation, or the acquisition and retardation of conditioned inhibition. However, prenatal choline availability significantly altered the contextual control of these learned behaviors. Both control and choline-deprived rats exhibited context specificity of conditioned excitation as exhibited by a loss in responding when tested in an alternate context after conditioning; in contrast, choline-supplemented rats showed no such effect. When switched to a different context following extinction, however, both choline-supplemented and control rats showed substantial contextual control of responding, whereas choline-deficient rats did not. These data support the view that configural associations that rely on hippocampal function are selectively sensitive to prenatal manipulations of dietary choline during prenatal development. PMID:19050158

  11. Adaptations of young adult rat cortical bone to 14 days of spaceflight

    NASA Technical Reports Server (NTRS)

    Vailas, A. C.; Vanderby, R., Jr.; Martinez, D. A.; Ashman, R. B.; Ulm, M. J.; Grindeland, R. E.; Durnova, G. N.; Kaplanskii, A.

    1992-01-01

    To determine whether mature humeral cortical bone would be modified significantly by an acute exposure to weightlessness, adult rats (110 days old) were subjected to 14 days of microgravity on the COSMOS 2044 biosatellite. There were no significant changes in peak force, stiffness, energy to failure, and displacement at failure in the flight rats compared with ground-based controls. Concentrations and contents of hydroxyproline, calcium, and mature stable hydroxylysylpyridinoline and lysylpyridinoline collagen cross-links remained unchanged after spaceflight. Bone lengths, cortical and endosteal areas, and regionl thicknesses showed no significant differences between flight animals and ground controls. The findings suggest that responsiveness of cortical bone to microgravity is less pronounced in adult rats than in previous spaceflight experiments in which young growing animals were used. It is hypothesized that 14 days of spaceflight may not be sufficient to impact the biochemical and biomechanical properties of cortical bone in the mature rat skeleton.

  12. Adult neurogenesis and its anatomical context in the hippocampus of three mole-rat species

    PubMed Central

    Amrein, Irmgard; Becker, Anton S.; Engler, Stefanie; Huang, Shih-hui; Müller, Julian; Slomianka, Lutz; Oosthuizen, Maria K.

    2014-01-01

    African mole-rats (family Bathyergidae) are small to medium sized, long-lived, and strictly subterranean rodents that became valuable animal models as a result of their longevity and diversity in social organization. The formation and integration of new hippocampal neurons in adult mammals (adult hippocampal neurogenesis, AHN) correlates negatively with age and positively with habitat complexity. Here we present quantitative data on AHN in wild-derived mole-rats of 1 year and older, and briefly describe its anatomical context including markers of neuronal function (calbindin and parvalbumin). Solitary Cape mole-rats (Georychus capensis), social highveld mole-rats (Cryptomys hottentotus pretoriae), and eusocial naked mole-rats (Heterocephalus glaber) were assessed. Compared to other rodents, the hippocampal formation in mole-rats is small, but shows a distinct cytoarchitecture in the dentate gyrus and CA1. Distributions of the calcium-binding proteins differ from those seen in rodents; e.g., calbindin in CA3 of naked mole-rats distributes similar to the pattern seen in early primate development, and calbindin staining extends into the stratum lacunosum-moleculare of Cape mole-rats. Proliferating cells and young neurons are found in low numbers in the hippocampus of all three mole-rat species. Resident granule cell numbers are low as well. Proliferating cells expressed as a percentage of resident granule cells are in the range of other rodents, while the percentage of young neurons is lower than that observed in surface dwelling rodents. Between mole-rat species, we observed no difference in the percentage of proliferating cells. The percentages of young neurons are high in social highveld and naked mole-rats, and low in solitary Cape mole-rats. The findings support that proliferation is regulated independently of average life expectancy and habitat. Instead, neuronal differentiation reflects species-specific demands, which appear lower in subterranean rodents. PMID

  13. BIOCHANIN A SHOWS NO EFFECT ON SKELETAL SYSTEM IN OVARIECTOMIZED RATS, WHEN ADMINISTERED IN MODERATE DOSE.

    PubMed

    Kaczmarczyk-Sedlak, Ilona; Zych, Maria; Wojnar, Weronika; Ozimina-Kamińska, Ewa; Dudek, Sławomir; Chadała, Natalia; Kachel, Agnieszka

    2015-01-01

    Biochanin A is a naturally occurring isoflavone. Its main sources are clover species such as Trifolium pretense, Trifolium subterraneum or Trifolium incarnatum. Phytoestrogens, including isoflavones, are plant-derived substances, which exhibit estrogen-like properties, thus they may be used as an alternative for hormonal replacement therapies and prevent postmenopausal osteoporosis. Therefore, the aim of the presented study, was to investigate the effect of biochanin A on chemistry and mechanical properties of skeletal system in rats with ovariectomy-induced osteoporosis. The animals were divided into 4 groups--(I) sham-operated rats, (II) ovariectomized rats, (III) ovariectomized rats receiving estradiol at a dose of 0.2 mg/kg p.o., which were a positive control, and (IV) ovariectomized rats receiving biochanin A at a dose of 5 mg/kg p.o. for four weeks. The administered dose of biochanin A is considered as moderate for human, which can be received in the dietary supplements, and was established using ten-fold conversion rate resulting from faster metabolism in rats. Obtained results showed that ovariectomy induced harmful changes in bone tissue, causing worsening in both chemistry and mechanical parameters in bones. Administration of biochanin A to ovariectomized rats did not affect any changes in bone tissue in comparison to the bones of untreated ovariectomized rats. There was neither improvement nor deterioration noted in chemical composition and mechanical properties in all analyzed bones. Basing on the results, it could be concluded, that biochanin A administered in a moderate dose shows no influence on bone tissue of rats with ovariectomy-induced osteoporosis.

  14. Effects of long-term methylphenidate treatment in adolescent and adult rats on hippocampal shape, functional connectivity and adult neurogenesis.

    PubMed

    van der Marel, K; Bouet, V; Meerhoff, G F; Freret, T; Boulouard, M; Dauphin, F; Klomp, A; Lucassen, P J; Homberg, J R; Dijkhuizen, R M; Reneman, L

    2015-11-19

    Methylphenidate (MPH) is a widely prescribed stimulant drug for the treatment of attention deficit hyperactivity disorder (ADHD) in children and adolescents. Its use in this age group raises concerns regarding the potential interference with ongoing neurodevelopmental processes. Particularly the hippocampus is a highly plastic brain region that continues to develop postnatally and is involved in cognition and emotional behavior, functions known to be affected by MPH. In this study, we assessed whether hippocampal structure and function were affected by chronic oral MPH treatment and whether its effects were different in adolescent or adult rats. Using behavioral testing, resting-state functional MRI, post-mortem structural magnetic resonance imaging (MRI), and immunohistochemistry, we assessed MPH's effects on recognition memory, depressive-like behavior, topological features of functional connectivity networks, hippocampal shape and markers for hippocampal neurogenesis and proliferation. Object recognition memory was transiently impaired in adolescent treated rats, while in animals treated during adulthood, increased depressive-like behavior was observed. Neurogenesis was increased in adolescent treated rats, whereas cell proliferation was decreased following adult treatment. Adolescent treated rats showed inward shape deformations adjacent to ventral parahippocampal regions known to be involved in recognition memory, whereas such deformations were not observed in adult treated animals. Irrespective of the age of treatment, MPH affected topological features of ventral hippocampal functional networks. Thus, chronic oral treatment with a therapeutically relevant dose of MPH preferentially affected the ventral part of the hippocampus and induced contrasting effects in adolescent and adult rats. The differences in behavior were paralleled by opposite effects on adult neurogenesis and granule cell proliferation.

  15. Respiratory autoresuscitation following severe acute hypoxemia in anesthetized adult rats.

    PubMed

    Krause, A; Nowak, Z; Srbu, R; Bell, H J

    2016-10-01

    In the present study we investigated the pattern and efficacy of respiratory autoresuscitation in spontaneously breathing adult male rats across three separate anesthetic backgrounds. Each animal was administered one of three injectable anesthetics to achieve a surgical plane of anesthesia: ketamine-xylazine (KET, n=10), pentobarbital (PEN, n=10), or urethane (URE, n=10). Animals were tracheostomized and equipped with a femoral artery catheter to record airflow and arterial pressures. In response to a bout of breathing anoxic air, none of the 10 URE animals were able to mount a successful autoresuscitation response. In contrast, all KET and PEN animals survived all four consecutive anoxic exposures, restoring eupneic breathing in all cases. Moreover, only 4/10 URE animals expressed gasping breaths following the onset of respiratory arrest, and these were temporally delayed (p<0.001) and much smaller in volume (P≤0.012) compared to KET and PEN animals. URE animals showed no clear aberrations in their cardiovascular responses to anoxia, with the exception of lower arterial pulse pressures compared to either KET or PEN animals at specific points following RA. Ketamine-xylazine and pentobarbital anesthesia can be reliably and effectively used to create models for the study of autoresuscitation in adult rats. In contrast, urethane causes catastrophic failure of respiratory autoresuscitation, by delaying or outright preventing the elaboration of gasping breaths following anoxia-induced respiratory arrest. The neuronal and synaptic alterations accompanying urethane anesthesia may therefore provide a means of understanding potential pathological alterations in rhythm generation that can predispose the respiratory control system to failed autoresuscitation following an episode of acute severe hypoxemia. PMID:27378495

  16. The Effects of Inflammatory Tooth Pain on Anxiety in Adult Male Rats

    PubMed Central

    Raoof, Maryam; Ebrahimnejad, Hamed; Abbasnejad, Mehdi; Amirkhosravi, Ladan; Raoof, Ramin; Esmaeili Mahani, Saeed; Ramazani, Mohsen; Shokouhinejad, Noushin; Khoshkhounejad, Mehrfam

    2016-01-01

    Introduction: This study aimed to examine the effects of induced inflammatory tooth pain on anxiety level in adult male rats. Methods: The mandibular incisors of 56 adult male rats were cut off and prefabricated crowns were fixed on the teeth. Formalin and capsaicin were injected intradentally to induce inflammatory tooth pain. Diazepam treated group received diazepam 30 minutes before intradental injection. The anxiety-related behavior was evaluated with elevated plus maze test. Results: Intradental application of chemical noxious stimuli, capsaicin and formalin, significantly affected nociceptive behaviors (P<0.001). Capsaicin (P<0.001) and formalin (P<0.01) significantly increased the anxiety levels in rats by decrease in the duration of time spent in open arm and increase in the duration of time spent in closed arm. Rats that received capsaicin made fewer open arm entries compared to the control animals (P<0.05). Capsaicin (P<0.001) and formalin (P<0.01) treated rats showed more stretch attend postures compared to the control and sham operated animals. In diazepampretreated rats, capsaicin induced algesic effect was prevented (P<0.001). Conclusion: Inflammatory pulpal pain has anxiogenic effect on rats, whereas diazepam premedication showed both anxiolytic and pain reducing effects. PMID:27563419

  17. Male rats show an indifference-avoidance response for increasing concentrations of the artificial sweetener sucralose.

    PubMed Central

    Bello, Nicholas T.; Hajnal, Andras

    2006-01-01

    Sucralose is a non-nutritive halogenated sucrose derivative that has been described by humans as tasting predominately sweet with little or no aftertaste. In this study we examined the preference for sucralose in adult male Sprague Dawley rats. A standard 24 hr two-bottle test was used to compare a wide range of sucralose concentrations (0.0003–10g/L; 0.8 μM–25 mM) with water. The rats did not prefer sucralose to water at low concentrations (0.0003–0.3 g/L) and avoided sucralose at high concentrations (1–10g/L). Although there are many similarities in the taste preference of humans, mice, and rats, these results suggest that male rats do not prefer sucralose and avoid it at high concentrations. An awareness of the potential species differences in preference testing for novel sweeteners is critical for the taste and nutritional research communities. PMID:16810335

  18. Methylphenidate treatment increases Na(+), K (+)-ATPase activity in the cerebrum of young and adult rats.

    PubMed

    Scherer, Emilene B S; Matté, Cristiane; Ferreira, Andréa G K; Gomes, Karin M; Comim, Clarissa M; Mattos, Cristiane; Quevedo, João; Streck, Emilio L; Wyse, Angela T S

    2009-12-01

    Methylphenidate is a central nervous system stimulant used for the treatment of attention-deficit hyperactivity disorder. Na(+), K(+)-ATPase is a membrane-bound enzyme necessary to maintain neuronal excitability. Considering that methylphenidate effects on central nervous system metabolism are poorly known and that Na(+), K(+)-ATPase is essential to normal brain function, the purpose of this study was to evaluate the effect of this drug on Na(+), K(+)-ATPase activity in the cerebrum of young and adult rats. For acute administration, a single injection of methylphenidate (1.0, 2.0, or 10.0 mg/Kg) or saline was given to rats on postnatal day 25 or postnatal day 60, in the young and adult groups, respectively. For chronic administration, methylphenidate (1.0, 2.0, or 10.0 mg/Kg) or saline injections were given to young rats starting at postnatal day 25 once daily for 28 days. In adult rats, the same regimen was performed starting at postnatal day 60. Our results showed that acute methylphenidate administration increased Na(+), K(+)-ATPase activity in hippocampus, prefrontal cortex, and striatum of young and adult rats. In young rats, chronic administration of methylphenidate also enhanced Na(+), K(+)-ATPase activity in hippocampus and prefrontal cortex, but not in striatum. When tested in adult rats, Na(+), K(+)-ATPase activity was increased in all cerebral structures studied. The present findings suggest that increased Na(+), K(+)-ATPase activity may be associated with neuronal excitability caused by methylphenidate.

  19. 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.

  20. 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

  1. Perinatal exposure to diethylstilbestrol alters the functional differentiation of the adult rat uterus.

    PubMed

    Bosquiazzo, Verónica L; Vigezzi, Lucía; Muñoz-de-Toro, Mónica; Luque, Enrique H

    2013-11-01

    The exposure to endocrine disrupters and female reproductive tract disorders has not been totally clarified. The present study assessed the long-term effect of perinatal (gestation+lactation) exposure to diethylstilbestrol (DES) on the rat uterus and the effect of estrogen replacement therapy. DES (5μg/kg bw/day) was administered in the drinking water from gestational day 9 until weaning and we studied the uterus of young adult (PND90) and adult (PND360) females. To investigate whether perinatal exposure to DES modified the uterine response to a long-lasting estrogen treatment, 12-month-old rats exposed to DES were ovariectomized and treated with 17β-estradiol for 3 months (PND460). In young adult rats (PND90), the DES treatment decreased both the proliferation of glandular epithelial cells and the percentage of glandular perimeter occupied by α-smooth muscle actin-positive cells. The other tissue compartments remained unchanged. Cell apoptosis was not altered in DES-exposed females. In control adult rats (PND360), there were some morphologically abnormal uterine glands. In adult rats exposed to DES, the incidence of glands with cellular anomalies increased. In response to estrogens (PND460), the incidence of cystic glands increased in the DES group. We observed glands with daughter glands and conglomerates of glands only on PND460 and in response to estrogen replacement therapy, independently of DES exposure. The p63 isoforms were expressed without changes on PND460. Estrogen receptors α and β showed no changes, while the progesterone receptor decreased in the subepithelial stroma of DES-exposed animals with estrogen treatment. The long-lasting effects of perinatal exposure to DES included the induction of abnormalities in uterine tissues of aged female rats and an altered response of the adult uterus to estradiol.

  2. Progesterone Treatment Shows Benefit in Female Rats in a Pediatric Model of Controlled Cortical Impact Injury

    PubMed Central

    Geddes, Rastafa I.; Peterson, Bethany L.; Stein, Donald G.; Sayeed, Iqbal

    2016-01-01

    Purpose We recently showed that progesterone treatment can reduce lesion size and behavioral deficits after moderate-to-severe bilateral injury to the medial prefrontal cortex in immature male rats. Whether there are important sex differences in response to injury and progesterone treatment in very young subjects has not been given sufficient attention. Here we investigated progesterone’s effects in the same model of brain injury but with pre-pubescent females. Methods Twenty-eight-day-old female Sprague-Dawley rats received sham (n = 14) or controlled cortical impact (CCI) (n = 21) injury, were given progesterone (8 mg/kg body weight) or vehicle injections on post-injury days (PID) 1–7, and underwent behavioral testing from PID 9–27. Brains were evaluated for lesion size at PID 28. Results Lesion size in vehicle-treated female rats with CCI injury was smaller than that previously reported for similarly treated age-matched male rats. Treatment with progesterone reduced the effect of CCI on extent of damage and behavioral deficits. Conclusion Pre-pubescent female rats with midline CCI injury to the frontal cortex have reduced morphological and functional deficits following progesterone treatment. While gender differences in susceptibility to this injury were observed, progesterone treatment produced beneficial effects in young rats of both sexes following CCI. PMID:26799561

  3. Dose related effects of nicotine on oxidative injury in young, adult and old rats.

    PubMed

    Jain, Anshu; Flora, S J S

    2012-03-01

    Nicotine affects a variety of cellular process ranging from induction of gene expression to secretion of hormones and modulation of enzymatic activities. The objective of the present study was to study the dose dependent toxicity of nicotine on the oxidative stress in young, adult and old rats which were administered 0.75, 3 and 6 mg kg(-1) nicotine as nicotine hydrogen tartarate intraperitoneally for a period of seven days. No changes were observed in blood catalase (CAT) activity and level of blood reactive oxygen species (ROS) in any of the age group at the lowest dose of nicotine. However, at the highest dose (6 mg kg(-1) nicotine) ROS level increased significantly from 1.17 to 1.41 microM ml(-1) in young rats and from 1.13 to 1.40 microM ml(-1) in old rats. However, no change was observed in blood ROS levels of adult rats. Administration of 3 mg kg(-1) nicotine resulted in an increase in level of reduced glutathione (GSH) in rats of all the age groups. The young animals were the most sensitive as a dose of 6 mg kg(-1) resulted in decline in the levels of reduced GSH to 0.89 mg ml(-1) as compared to normal control (1.03 mg ml(-1)). The antioxidant enzymes SOD and CAT were sensitive to a dose of 6 mg kg(-1) as it resulted in decline of the enzymatic activity in all age group animals. Also, administration of nicotine at a lower dose of 3 mg kg(-1) inhibited SOD activity from 1.48 to 1.20 units min(-1) mg(-1) protein in old rats. Catalase activity showed a similar trend at a dose of 3 mg kg(-1). Administration of nicotine also increased the blood lipid peroxidation levels at all three doses in young and old rats dose dependently. Nicotine exposure also increased ROS in brain at the doses of 3 and 6 mg kg(-1) in all the three age groups. Brain GSH decreased significantly at high dose of nicotine (6 mg kg(-1) b.wt.) in adult rats (4.27 mg g(-1)) and old rats (3.68 mg g(-1)) but in young rats level increased to 4.40 mg g(-1) at the lower dose (0.75 mg kg nicotine

  4. Prolonged performance of a high repetition low force task induces bone adaptation in young adult rats, but loss in mature rats.

    PubMed

    Massicotte, Vicky S; Frara, Nagat; Harris, Michele Y; Amin, Mamta; Wade, Christine K; Popoff, Steven N; Barbe, Mary F

    2015-12-01

    We have shown that prolonged repetitive reaching and grasping tasks lead to exposure-dependent changes in bone microarchitecture and inflammatory cytokines in young adult rats. Since aging mammals show increased tissue inflammatory cytokines, we sought here to determine if aging, combined with prolonged performance of a repetitive upper extremity task, enhances bone loss. We examined the radius, forearm flexor muscles, and serum from 16 mature (14-18 months of age) and 14 young adult (2.5-6.5 months of age) female rats after performance of a high repetition low force (HRLF) reaching and grasping task for 12 weeks. Young adult HRLF rats showed enhanced radial bone growth (e.g., increased trabecular bone volume, osteoblast numbers, bone formation rate, and mid-diaphyseal periosteal perimeter), compared to age-matched controls. Mature HRLF rats showed several indices of radial bone loss (e.g., decreased trabecular bone volume, and increased cortical bone thinning, porosity, resorptive spaces and woven bone formation), increased osteoclast numbers and inflammatory cytokines, compared to age-matched controls and young adult HRLF rats. Mature rats weighed more yet had lower maximum reflexive grip strength, than young adult rats, although each age group was able to pull at the required reach rate (4 reaches/min) and required submaximal pulling force (30 force-grams) for a food reward. Serum estrogen levels and flexor digitorum muscle size were similar in each age group. Thus, mature rats had increased bone degradative changes than in young adult rats performing the same repetitive task for 12 weeks, with increased inflammatory cytokine responses and osteoclast activity as possible causes. PMID:26517953

  5. Prolonged performance of a high repetition low force task induces bone adaptation in young adult rats, but loss in mature rats.

    PubMed

    Massicotte, Vicky S; Frara, Nagat; Harris, Michele Y; Amin, Mamta; Wade, Christine K; Popoff, Steven N; Barbe, Mary F

    2015-12-01

    We have shown that prolonged repetitive reaching and grasping tasks lead to exposure-dependent changes in bone microarchitecture and inflammatory cytokines in young adult rats. Since aging mammals show increased tissue inflammatory cytokines, we sought here to determine if aging, combined with prolonged performance of a repetitive upper extremity task, enhances bone loss. We examined the radius, forearm flexor muscles, and serum from 16 mature (14-18 months of age) and 14 young adult (2.5-6.5 months of age) female rats after performance of a high repetition low force (HRLF) reaching and grasping task for 12 weeks. Young adult HRLF rats showed enhanced radial bone growth (e.g., increased trabecular bone volume, osteoblast numbers, bone formation rate, and mid-diaphyseal periosteal perimeter), compared to age-matched controls. Mature HRLF rats showed several indices of radial bone loss (e.g., decreased trabecular bone volume, and increased cortical bone thinning, porosity, resorptive spaces and woven bone formation), increased osteoclast numbers and inflammatory cytokines, compared to age-matched controls and young adult HRLF rats. Mature rats weighed more yet had lower maximum reflexive grip strength, than young adult rats, although each age group was able to pull at the required reach rate (4 reaches/min) and required submaximal pulling force (30 force-grams) for a food reward. Serum estrogen levels and flexor digitorum muscle size were similar in each age group. Thus, mature rats had increased bone degradative changes than in young adult rats performing the same repetitive task for 12 weeks, with increased inflammatory cytokine responses and osteoclast activity as possible causes.

  6. 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

  7. Physiological and behavioral effects of acute ethanol hangover in juvenile, adolescent, and adult rats.

    PubMed

    Brasser, Susan M; Spear, Norman E

    2002-04-01

    This study examined differential responding of juvenile, adolescent, and adult rats after intoxication from an acute alcohol challenge. Experiment I generated blood ethanol curves for subjects 25, 35, or 110 days postnatal, after doses of 2.0 or 4.0 g/kg, assessing elimination rates and time of drug clearance. Experiment 2 compared ethanol's initial hypothermic and delayed hyperthermic effect across age by 48-hr temperature measurement with telemetry. At clearance or 24 hr after alcohol exposure, Experiment 3 tested subjects for changes in acoustic startle reactivity and ultrasonic vocalization (USV). Younger rats showed an absent or reduced tendency for residual hyperthermia, and adults showed alterations in USV observed as aftereffects of intoxication, despite greater initial blood alcohol levels and ethanol hypothermia in the former. The lesser ethanol hangover effects in weanlings and adolescents may be due in part to faster ethanol elimination at these ages compared with adults.

  8. Human apolipoprotein B transgenic SHR/NDmcr-cp rats show exacerbated kidney dysfunction.

    PubMed

    Asahina, Makoto; Shimizu, Fumi; Ohta, Masayuki; Takeyama, Michiyasu; Tozawa, Ryuichi

    2015-01-01

    Nephropathy frequently co-occurs with metabolic syndrome in humans. Metabolic syndrome is a cluster of metabolic diseases including obesity, diabetes, hypertension, and dyslipidemia, and some previous studies revealed that dyslipidemia contributes to the progression of kidney dysfunction. To establish a new nephropathy model with metabolic syndrome, we produced human apolipoprotein B (apoB) transgenic (Tg.) SHR/NDmcr-cp (SHR-cp/cp) rats, in which dyslipidemia is exacerbated more than in an established metabolic syndrome model, SHR-cp/cp rats. Human apoB Tg. SHR-cp/cp rats showed obesity, hyperinsulinemia, hypertension, and severe hyperlipidemia. They also exhibited exacerbated early-onset proteinuria, accompanied by increased kidney injury and increased oxidative and inflammatory markers. Histological analyses revealed the characteristic features of human apoB Tg. SHR-cp/cp rats including prominent glomerulosclerosis with lipid accumulation. Our newly established human apoB Tg. SHR-cp/cp rat could be a useful model for the nephropathy in metabolic syndrome and for understanding the interaction between dyslipidemia and renal dysfunction in metabolic syndrome.

  9. Reinstatement of cocaine seeking induced by drugs, cues, and stress in adolescent and adult rats

    PubMed Central

    Carroll, Marilyn E.

    2010-01-01

    Rationale In human and animal studies, adolescence marks a period of increased vulnerability to the initiation and subsequent abuse of drugs. Adolescents may be especially vulnerable to relapse, and a critical aspect of drug abuse is that it is a chronically relapsing disorder. However, little is known of how vulnerability factors such as adolescence are related to conditions that induce relapse, triggered by the drug itself, drug-associated cues, or stress. Objective The purpose of this study was to compare adolescent and adult rats on drug-, cue-, and stress-induced reinstatement of cocaine-seeking behavior. Methods On postnatal days 23 (adolescents) and 90 (adults), rats were implanted with intravenous catheters and trained to lever press for i.v. infusions of cocaine (0.4 mg/kg) during two daily 2-h sessions. The rats then self-administered i.v. cocaine for ten additional sessions. Subsequently, visual and auditory stimuli that signaled drug delivery were unplugged, and rats were allowed to extinguish lever pressing for 20 sessions. Rats were then tested on cocaine-, cue-, and yohimbine (stress)-induced cocaine seeking using a within-subject multicomponent reinstatement procedure. Results Results indicated that adolescents had heightened cocaine seeking during maintenance and extinction compared to adults. During reinstatement, adolescents (vs adults) responded more following cocaine- and yohimbine injections, while adults (vs adolescents) showed greater responding following presentations of drug-associated cues. Conclusion These results demonstrated that adolescents and adults differed across several measures of drug-seeking behavior, and adolescents may be especially vulnerable to relapse precipitated by drugs and stress. PMID:19953228

  10. Prenatal lipopolysaccharide exposure increases depression-like behaviors and reduces hippocampal neurogenesis in adult rats.

    PubMed

    Lin, Yu-Lung; Wang, Sabrina

    2014-02-01

    Major depression is one of the most prevalent mental disorders in the population. In addition to genetic influences, disturbances in fetal nervous system development might be a contributing factor. Maternal infection during pregnancy may affect fetal brain development and consequently lead to neurological and mental disorders. Previously, we used low-dose lipopolysaccharide (LPS) exposure on embryonic day 10.5 to mimic mild maternal infection in rats and found that dopaminergic and serotonergic neurons were reduced in the offspring. The offspring also showed more anxiety-like behavior and an enhanced stress response. In the present study we used forced swim test and chronic mild stress challenge to assess depression-like behaviors in the affected offspring and examined their adult hippocampal neurogenesis and brain-derived neurotrophic factor (BDNF) concentration. Our results showed that prenatally LPS-exposed rats (LPS rats) displayed more depression-like behaviors and had reduced adult neurogenesis and BDNF. The behavioral abnormalities and reduction in adult neurogenesis could be reversed by chronic fluoxetine (FLX) treatment. This study demonstrates that during the critical time of embryonic development LPS exposure can produce long-term behavioral changes and reduction in adult neurogenesis. The findings of enhanced depression-like behaviors, reduced adult neurogenesis, and their responsiveness to chronic antidepressant treatment suggest that prenatal LPS exposure could serve as an animal model of depression.

  11. Cocaine self-administration punished by intravenous histamine in adolescent and adult rats

    PubMed Central

    Holtz, Nathan A.; Carroll, Marilyn E.

    2016-01-01

    Adolescence is a transitional phase marked by a heightened vulnerability to substances of abuse. It has been hypothesized that both increased sensitivity to reward and decreased sensitivity to aversive events may drive drug-use liability during this phase. To investigate possible age-related differences in sensitivity to the aversive consequences of drug use, adolescent and adult rats were compared on self-administration of cocaine before, during, and after a 10-day period in which an aversive agent, histamine, was added to the cocaine solution. Adult and adolescent female rats were trained to self-administer intravenous cocaine (0.4 mg/kg/infusion) over 10 sessions (2 h/session; 2 sessions/day). Histamine (4 mg/kg/infusion) was then added directly into the cocaine solution for the next 10 sessions. Finally, the cocaine/histamine solution was replaced with a cocaine-only solution, and rats continued to self-administer cocaine (0.4 mg/kg) for 20 sessions. Compared with adolescent rats, adult rats showed a greater decrease in cocaine self-administration when it was punished with intravenous histamine compared with their baseline cocaine self-administration rates. These results suggest that differences in the sensitivity to negative consequences of drug use may partially explain developmental differences in drug use vulnerability. PMID:25769092

  12. Impact of prenatal and acute methamphetamine exposure on behaviour of adult male rats.

    PubMed

    Schutová, B; Hrubá, L; Pometlová, M; Slamberová, R

    2009-01-01

    Psychostimulants have been shown to alter behaviour in both rats and humans. The aim of the present study was: (1) to assess the effect of prenatal and acute methamphetamine (MA) administration on behaviour in adult male rats and (2) to find out if the prenatal exposure to MA increases sensitivity to acute MA application in adulthood. Behaviour of adult male rats prenatally exposed to MA (5 mg/kg) or no drug was tested in Open field (OF) and Elevated plus maze (EPM). Half of the animals were injected with MA (1 mg/kg) subcutaneously 30 minutes prior to testing. Locomotion, exploration, comforting behaviour and anxiety were evaluated in the OF, while anxiety and exploratory behaviour were assessed in the EPM. Our results showed that prenatal MA did not have an effect on baseline behaviour in either of the tests. By contrast, acute MA increased overall psychomotor activity by increasing locomotion and exploratory behaviour and decreasing comforting behaviour. Moreover, adult rats prenatally exposed to MA were more sensitive to the effects of acute MA on exploration. In addition, acute MA application decreased anxiety in the OF as well as in the EPM. Our present study, thus, demonstrates that acute MA increases overall psychomotor activity and decreases anxiety to novel environment. To further support our hypothesis that prenatal MA exposure increases sensitivity to drugs in adulthood, studies investigating the levels of dopamine in the rat brain after prenatal MA exposure are planned.

  13. Cocaine self-administration punished by intravenous histamine in adolescent and adult rats.

    PubMed

    Holtz, Nathan A; Carroll, Marilyn E

    2015-06-01

    Adolescence is a transitional phase marked by a heightened vulnerability to substances of abuse. It has been hypothesized that both increased sensitivity to reward and decreased sensitivity to aversive events may drive drug-use liability during this phase. To investigate possible age-related differences in sensitivity to the aversive consequences of drug use, adolescent and adult rats were compared on self-administration of cocaine before, during, and after a 10-day period in which an aversive agent, histamine, was added to the cocaine solution. Adult and adolescent female rats were trained to self-administer intravenous cocaine (0.4 mg/kg/infusion) over 10 sessions (2 h/session; 2 sessions/day). Histamine (4 mg/kg/infusion) was then added directly into the cocaine solution for the next 10 sessions. Finally, the cocaine/histamine solution was replaced with a cocaine-only solution, and rats continued to self-administer cocaine (0.4 mg/kg) for 20 sessions. Compared with adolescent rats, adult rats showed a greater decrease in cocaine self-administration when it was punished with intravenous histamine compared with their baseline cocaine self-administration rates. These results suggest that differences in the sensitivity to negative consequences of drug use may partially explain developmental differences in drug use vulnerability.

  14. Trading new neurons for status: Adult hippocampal neurogenesis in eusocial Damaraland mole-rats.

    PubMed

    Oosthuizen, M K; Amrein, I

    2016-06-01

    Diversity in social structures, from solitary to eusocial, is a prominent feature of subterranean African mole-rat species. Damaraland mole-rats are eusocial, they live in colonies that are characterized by a reproductive division of labor and a subdivision into castes based on physiology and behavior. Damaraland mole-rats are exceptionally long lived and reproductive animals show delayed aging compared to non-reproductive animals. In the present study, we described the hippocampal architecture and the rate of hippocampal neurogenesis of wild-derived, adult Damaraland mole-rats in relation to sex, relative age and social status or caste. Overall, Damaraland mole-rats were found to have a small hippocampus and low rates of neurogenesis. We found no correlation between neurogenesis and sex or relative age. Social status or caste was the most prominent modulator of neurogenesis. An inverse relationship between neurogenesis and social status was apparent, with queens displaying the lowest neurogenesis while the worker mole-rats had the most. As there is no natural progression from one caste to another, social status within a colony was relatively stable and is reflected in the level of neurogenesis. Our results correspond to those found in the naked mole-rat, and may reflect an evolutionary and environmentally conserved trait within social mole-rat species. PMID:26979050

  15. Radial glia-like cells persist in the adult rat brain.

    PubMed

    Gubert, Fernanda; Zaverucha-do-Valle, Camila; Pimentel-Coelho, Pedro M; Mendez-Otero, Rosalia; Santiago, Marcelo F

    2009-03-01

    During development, radial glia cells contribute to neuronal migration and neurogenesis, and differentiate into astrocytes by the end of the developmental period. Recently, it was demonstrated that during development, radial glia cells, in addition to their role in migration, also give rise to neuroblasts. Furthermore, radial glial cells remain in the adult brain as adult neural stem cells (NSC) in the subventricular zone (SVZ) around the lateral ventricles (LVs), and generate new neurons continuously throughout adulthood. In this study, we used immunohistochemical and morphological methods to investigate the presence of radial glia-like cells around the LVs during the postnatal development period until adulthood in rats. In all ages of rats studied, we identified cells with morphological and immunocytochemical features that are similar to the radial glia cells found in the embryonic brain. Similarly to the radial glia, these cells express nestin and vimentin, and have a radial morphology, extending perpendicularly as processes from the ventricle wall. These cells also express GFAP, GLAST, and Pax6, and proliferate. In the brains of adult rats, we identified cells with relatively long processes (up to 600 mum) in close apposition with migrating neuroblasts. Our results showed that the radial glia-like cells present in the adult rat brain share several morphological and functional characteristics with the embryonic radial glia. We suggest that the embryonic radial glia cells located around the LV walls do not complete their transformation into astrocytes, but rather persist in adulthood.

  16. Adolescent earthquake survivors' show increased prefrontal cortex activation to masked earthquake images as adults.

    PubMed

    Du, Xue; Wei, Dongtao; Ganzel, Barbara L; Kim, Pilyoung; Zhang, Qinglin; Qiu, Jiang

    2015-03-01

    The great Sichuan earthquake in China on May 12, 2008 was a traumatic event to many who live near the earthquake area. However, at present, there are few studies that explore the long-term impact of the adolescent trauma exposure on adults' brain function. In the present study, we used functional magnetic resonance imaging (fMRI) to investigate the brain activation evoked by masked trauma-related stimuli (earthquake versus neutral images) in 14 adults who lived near the epicenter of the great Sichuan earthquake when they were adolescents (trauma-exposed group) and 14 adults who lived farther from the epicenter of the earthquake when they were adolescents (control group). Compared with the control group, the trauma-exposed group showed significant elevation of activation in the right anterior cingulate cortex (ACC) and the medial prefrontal cortex (MPFC) in response to masked earthquake-related images. In the trauma-exposed group, the right ACC activation was negatively correlated with the frequency of symptoms of post-traumatic stress disorder (PTSD). These findings differ markedly from the long-term effects of trauma exposure in adults. This suggests that trauma exposure during adolescence may have a unique long-term impact on ACC/MPFC function, top-down modulation of trauma-related information, and subsequent symptoms of PTSD.

  17. Desvenlafaxine may accelerate neuronal maturation in the dentate gyri of adult male rats.

    PubMed

    Asokan, Aditya; Ball, Alan R; Laird, Christina D; Hermer, Linda; Ormerod, Brandi K

    2014-01-01

    Adult hippocampal neurogenesis has been linked to the effects of anti-depressant drugs on behavior in rodent models of depression. To explore this link further, we tested whether the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine impacted adult hippocampal neurogenesis differently than its primary active SNRI metabolite desvenlafaxine. Adult male Long Evans rats (n = 5-6 per group) were fed vehicle, venlafaxine (0.5 or 5 mg) or desvenlafaxine (0.5 or 5 mg) twice daily for 16 days. Beginning the third day of drug treatment, the rats were given a daily bromodeoxyuridine (BrdU; 50 mg/kg) injection for 5 days to label dividing cells and then perfused 2 weeks after the first BrdU injection to confirm total new hippocampal cell numbers and their phenotypes. The high desvenlafaxine dose increased total new BrdU+ cell number and appeared to accelerate neuronal maturation because fewer BrdU+ cells expressed maturing neuronal phenotypes and more expressed mature neuronal phenotypes in the dentate gyri of these versus vehicle-treated rats. While net neurogenesis was not increased in the dentate gyri of rats treated with the high desvenlafaxine dose, significantly more mature neurons were detected. Our data expand the body of literature showing that antidepressants impact adult neurogenesis by stimulating NPC proliferation and perhaps the survival of neuronal progeny and by showing that a high dose of the SNRI antidepressant desvenlafaxine, but neither a high nor low venlafaxine dose, may also accelerate neuronal maturation in the adult rat hippocampus. These data support the hypothesis that hippocampal neurogenesis may indeed serve as a biomarker of depression and the effects of antidepressant treatment, and may be informative for developing novel fast-acting antidepressant strategies.

  18. Reproductive toxicity of DDT in adult male rats.

    PubMed

    Ben Rhouma, K; Tébourbi, O; Krichah, R; Sakly, M

    2001-08-01

    The reproductive toxicity of DDT was investigated in adult male rats exposed to 50 and 100 mg/kg body weight (b.wt) day(-1) for 10 successive days. Compared with control animals, administration of DDT led to a dose-dependent reduction of testicular weight and the number as well as the percentage of motile spermatozoa in the epididymis. Testicular histological observations revealed also a marked loss of gametes in the lumen of seminiferous tubules. In DDT-treated rats, the seminal vesicles weights dropped significantly, resulting from a decrease of testosterone production by testes, whereas serum LH and FSH increased after pesticide exposure. This increase of gonadotrophin levels may be related to an impairment of the negative feedback exerted by the steroid on the hypothalamic--pituitary axis. It is concluded that DDT induced adverse effects on male rat fertility by acting directly on the testes and altering the neuroendocrine function.

  19. Activity/inactivity circadian rhythm shows high similarities between young obesity-induced rats and old rats.

    PubMed

    Bravo Santos, R; Delgado, J; Cubero, J; Franco, L; Ruiz-Moyano, S; Mesa, M; Rodríguez, A B; Uguz, C; Barriga, C

    2016-03-01

    The objective of the present study was to compare differences between elderly rats and young obesity-induced rats in their activity/inactivity circadian rhythm. The investigation was motivated by the differences reported previously for the circadian rhythms of both obese and elderly humans (and other animals), and those of healthy, young or mature individuals. Three groups of rats were formed: a young control group which was fed a standard chow for rodents; a young obesity-induced group which was fed a high-fat diet for four months; and an elderly control group with rats aged 2.5 years that was fed a standard chow for rodents. Activity/inactivity data were registered through actimetry using infrared actimeter systems in each cage to detect activity. Data were logged on a computer and chronobiological analysis were performed. The results showed diurnal activity (sleep time), nocturnal activity (awake time), amplitude, acrophase, and interdaily stability to be similar between the young obesity-induced group and the elderly control group, but different in the young control group. We have concluded that obesity leads to a chronodisruption status in the body similar to the circadian rhythm degradation observed in the elderly. PMID:27030628

  20. Activity/inactivity circadian rhythm shows high similarities between young obesity-induced rats and old rats.

    PubMed

    Bravo Santos, R; Delgado, J; Cubero, J; Franco, L; Ruiz-Moyano, S; Mesa, M; Rodríguez, A B; Uguz, C; Barriga, C

    2016-03-01

    The objective of the present study was to compare differences between elderly rats and young obesity-induced rats in their activity/inactivity circadian rhythm. The investigation was motivated by the differences reported previously for the circadian rhythms of both obese and elderly humans (and other animals), and those of healthy, young or mature individuals. Three groups of rats were formed: a young control group which was fed a standard chow for rodents; a young obesity-induced group which was fed a high-fat diet for four months; and an elderly control group with rats aged 2.5 years that was fed a standard chow for rodents. Activity/inactivity data were registered through actimetry using infrared actimeter systems in each cage to detect activity. Data were logged on a computer and chronobiological analysis were performed. The results showed diurnal activity (sleep time), nocturnal activity (awake time), amplitude, acrophase, and interdaily stability to be similar between the young obesity-induced group and the elderly control group, but different in the young control group. We have concluded that obesity leads to a chronodisruption status in the body similar to the circadian rhythm degradation observed in the elderly.

  1. The role of testicular hormones and luteinizing hormone in spatial memory in adult male rats.

    PubMed

    McConnell, Sarah E A; Alla, Juliet; Wheat, Elizabeth; Romeo, Russell D; McEwen, Bruce; Thornton, Janice E

    2012-04-01

    Attempts to determine the influence of testicular hormones on learning and memory in males have yielded contradictory results. The present studies examined whether testicular hormones are important for maximal levels of spatial memory in young adult male rats. To minimize any effect of stress, we used the Object Location Task which is a spatial working memory task that does not involve food or water deprivation or aversive stimuli for motivation. In Experiment 1 sham gonadectomized male rats demonstrated robust spatial memory, but gonadectomized males showed diminished spatial memory. In Experiment 2 subcutaneous testosterone (T) capsules restored spatial memory performance in gonadectomized male rats, while rats with blank capsules demonstrated compromised spatial memory. In Experiment 3, gonadectomized male rats implanted with blank capsules again showed compromised spatial memory, while those with T, dihydrotestosterone (DHT), or estradiol (E) capsules demonstrated robust spatial memory, indicating that T's effects may be mediated by its conversion to E or to DHT. Gonadectomized male rats injected with Antide, a gonadotropin-releasing hormone receptor antagonist which lowers luteinizing hormone levels, also demonstrated spatial memory, comparable to that shown by T-, E-, or DHT-treated males. These data indicate that testicular androgens are important for maximal levels of spatial working memory in male rats, that testosterone may be converted to E and/or DHT to exert its effects, and that some of the effects of these steroid hormones may occur via negative feedback effects on LH.

  2. Ketone-body utilization by homogenates of adult rat brain

    SciTech Connect

    Lopes-Cardozo, M.; Klein, W.

    1982-06-01

    The regulation of ketone-body metabolism and the quantitative importance of ketone bodies as lipid precursors in adult rat brain has been studied in vitro. Utilization of ketone bodies and of pyruvate by homogenates of adult rat brain was measured and the distribution of /sup 14/C from (3-/sup 14/C)ketone bodies among the metabolic products was analysed. The rate of ketone-body utilization was maximal in the presence of added Krebs-cycle intermediates and uncouplers of oxidative phosphorylation. The consumption of acetoacetate was faster than that of D-3-hydroxybutyrate, whereas, pyruvate produced twice as much acetyl-CoA as acetoacetate under optimal conditions. Millimolar concentrations of ATP in the presence of uncoupler lowered the consumption of ketone bodies but not of pyruvate. Indirect evidence is presented suggesting that ATP interferes specifically with the mitochondrial uptake of ketone bodies. Interconversion of ketone bodies and the accumulation of acid-soluble intermediates (mainly citrate and glutamate) accounted for the major part of ketone-body utilization, whereas only a small part was oxidized to CO/sub 2/. Ketone bodies were not incorporated into lipids or protein. We conclude that adult rat-brain homogenates use ketone bodies exclusively for oxidative purposes.

  3. Effects of neonatal methamphetamine treatment on adult stress-induced corticosterone release in rats.

    PubMed

    Grace, Curtis E; Schaefer, Tori L; Herring, Nicole R; Williams, Michael T; Vorhees, Charles V

    2012-01-01

    In rats, neonatal (+)-methamphetamine (MA) exposure and maternal separation stress increase corticosterone during treatment and result in learning and memory impairments later in life. Early-life stress also changes later responses to acute stress. We tested the hypothesis that neonatal MA exposure would alter adult corticosterone after acute stress or MA challenge. Rats were treated with MA (10 mg/kg × 4/day), saline, or handling on postnatal (P) days 11-15 or 11-20 (days that lead to learning and memory impairments at this dose). As adults, corticosterone was measured before and after 15 min forced swim (FS) or 15 min forced confinement (FC), counterbalanced, and after an acute MA challenge (10 mg/kg) given last. FS increased corticosterone more than FC; order and stress type interacted but did not interact with treatment; treatment interacted with FS but not with FC. In the P11-15 regimen, MA-treated rats showed more rapid increases in corticosterone after FS than controls. In the P11-20 regimen, MA-treated rats showed a trend toward more rapid decrease in corticosterone after FS. No differences were found after MA challenge. The data do not support the hypothesis that neonatal MA causes changes in adult stress responsiveness to FS, FC, or an acute MA challenge.

  4. Intestinal absorption of aspartame decomposition products in adult rats.

    PubMed

    Lipton, W E; Li, Y N; Younoszai, M K; Stegink, L D

    1991-12-01

    The dipeptide sweetener aspartame (N-L-alpha-aspartyl-L-phenylalanine, 1-methyl ester; alpha-APM) is relatively stable in dry powder form. However, when exposed to elevated temperature, extremes of pH and/or moisture, alpha-APM is converted into a variety of products. In aqueous solution alpha-APM decomposes to yield methanol, two isomeric forms of L-aspartyl-L-phenylalanine (Asp-Phe) [alpha-Asp-Phe and beta-Asp-Phe], and APM's diketopiperazine cyclo-Asp-Phe. Depending on beverage storage conditions, individuals drinking alpha-APM-sweetened beverages may consume small quantities of these three compounds. Relatively little has been published about the metabolism of beta-Asp-Phe and cyclo-Asp-Phe. We compared the absorption and metabolism of alpha-Asp-Phe, beta-Asp-Phe, and cyclo-Asp-Phe with that of L-phenylalanine (Phe) in adult rats. Steady-state perfusion studies of rat jejunum indicated rapid carrier-assisted uptake of Phe and alpha-Asp-Phe, but only slow passive diffusion of beta-Asp-Phe and cyclo-Asp-Phe from the lumen. Homogenates of rat intestinal mucosa, liver, and cecal contents, as well as homogenates of pure cultures of Escherichia coli B, catalyzed the hydrolysis of alpha-Asp-Phe, but not cyclo-Asp-Phe. Homogenates of E coli and rat cecal contents, but not homogenates of rat liver or intestinal mucosa catalyzed the hydrolysis of beta-Asp-Phe.

  5. Caffeine in the neonatal period induces long-lasting changes in sleep and breathing in adult rats.

    PubMed

    Montandon, Gaspard; Horner, Richard L; Kinkead, Richard; Bairam, Aida

    2009-11-15

    Caffeine is commonly used clinically to treat apnoeas and unstable breathing associated with premature birth. Caffeine antagonizes adenosine receptors and acts as an efficient respiratory stimulant in neonates. Owing to its persistent effects on adenosine receptor expression in the brain, neonatal caffeine administration also has significant effects on maturation of the respiratory control system. However, since adenosine receptors are critically involved in sleep regulation, and sleep also modulates breathing, we tested the hypothesis that neonatal caffeine treatment disrupts regulation of sleep and breathing in the adult rat. Neonatal caffeine treatment (15 mg kg(-1) day(-1)) was administered from postnatal days 3-12. At adulthood (8-10 weeks old), sleep and breathing were measured with a telemetry system and whole-body plethysmography respectively. In adult rats treated with caffeine during the neonatal period, sleep time was reduced, sleep onset latency was increased, and non-rapid eye movement (non-REM) sleep was fragmented compared to controls. Ventilation at rest was higher in caffeine-treated adult rats compared to controls across sleep/wake states. Hypercapnic ventilatory responses were significantly reduced in caffeine-treated rats compared to control rats across sleep/wake states. Additional experiments in adult anaesthetized rats showed that at similar levels of arterial blood gases, phrenic nerve activity was enhanced in caffeine-treated rats. This study demonstrates that administration of caffeine in the neonatal period alters respiratory control system activity in awake and sleeping rats, as well as in the anaesthetized rats, and also has persistent disrupting effects on sleep that are apparent in adult rats.

  6. Plexin a4 expression in adult rat cranial nerves.

    PubMed

    Gutekunst, Claire-Anne; Gross, Robert E

    2014-11-01

    PlexinsA1-A4 participate in class 3 semaphorin signaling as co-receptors to neuropilin 1 and 2. PlexinA4 is the latest member of the PlexinA subfamily to be identified. In previous studies, we described the expression of PlexinA4 in the brain and spinal cord of the adult rat. Here, antibodies to PlexinA4 were used to reveal immunolabeling in most of the cranial nerve surveyed. Labeling was found in the olfactory, optic, oculomotor, trochlear, trigeminal, abducens, facial, vestibulocochlear, glossopharyngeal, vagus, and hypoglossal nerves. This is the first detailed description of the cellular and subcellular distribution of PlexinA4 in the adult cranial nerves. The findings will set the basis for future studies on the potential role of PlexinA4 in regeneration and repair of the adult central and peripheral nervous system.

  7. 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

  8. Adult Rats Treated with Risperidone during Development Are Hyperactive

    PubMed Central

    Bardgett, Mark E.; Franks-Henry, Julie M.; Colemire, Kristin R.; Juneau, Kathleen R.; Stevens, Rachel M.; Marczinski, Cecile A.; Griffith, Molly S.

    2014-01-01

    Risperidone is an antipsychotic drug approved for use in children, but little is known about the long-term effects of early-life risperidone treatment. In animals, prolonged risperidone administration during development increases forebrain dopamine receptor expression immediately upon the cessation of treatment. A series of experiments was performed to ascertain whether early-life risperidone administration altered locomotor activity, a behavior sensitive to dopamine receptor function, in adult rats. One additional behavior modulated by forebrain dopamine function, spatial reversal learning, was also measured during adulthood. In each study, Long-Evans rats received daily subcutaneous injections of vehicle or one of two doses of risperidone (1.0 and 3.0 mg/kg per day) from postnatal days 14 – 42. Weight gain during development was slightly yet significantly reduced in risperidone-treated rats. In the first two experiments, early-life risperidone administration was associated with increased locomotor activity at one week post-administration through approximately nine months of age, independent of changes in weight gain. In a separate experiment, it was found that the enhancing effect of early-life risperidone on locomotor activity occurred in males and female rats. A final experiment indicated that spatial reversal learning was unaffected in adult rats administered risperidone early in life. These results indicate that locomotor activity during adulthood is permanently modified by early-life risperidone treatment. The findings suggest that chronic antipsychotic drug use in pediatric populations (e.g., treatment for the symptoms of autism) could modify brain development and alter neural set-points for specific behaviors during adulthood. PMID:23750695

  9. Beer promotes high levels of alcohol intake in adolescent and adult alcohol-preferring rats.

    PubMed

    Hargreaves, Garth A; Wang, Emyo Y J; Lawrence, Andrew J; McGregor, Iain S

    2011-08-01

    Previous studies suggest that high levels of alcohol consumption can be obtained in laboratory rats by using beer as a test solution. The present study extended these observations to examine the intake of beer and equivalent dilute ethanol solutions with an inbred line of alcohol-preferring P rats. In Experiment 1, male adolescent P rats and age-matched Wistar rats had access to either beer or equivalent ethanol solutions for 1h daily in a custom-built lickometer apparatus. In subsequent experiments, adolescent (Experiment 2) and adult (Experiment 3) male P rats were given continuous 24-h home cage access to beer or dilute ethanol solutions, with concomitant access to lab chow and water. In each experiment, the alcohol content of the beer and dilute ethanol solutions was gradually increased from 0.4, 1.4, 2.4, 3.4, 4.4, 5 to 10% EtOH (vol/vol). All three experiments showed a major augmentation of alcohol intake when rats were given beer compared with equivalent ethanol solutions. In Experiment 1, the overall intake of beer was higher in P rats compared with Wistar rats, but no strain difference was found during the 1-h sessions with plain ethanol consumption. Experiment 1 also showed that an alcohol deprivation effect was more readily obtained in rats with a history of consuming beer rather than plain ethanol solutions. In Experiments 2 and 3, voluntary beer intake in P rats represented ethanol intake of 10-15 g/kg/day, among the highest reported in any study with rats. This excessive consumption was most apparent in adolescent rats. Beer consumption markedly exceeded plain ethanol intake in these experiments except at the highest alcohol concentration (10%) tested. The advantage of using beer rather than dilute ethanol solutions in both selected and nonselected rat strains is therefore confirmed. Our findings encourage the use of beer with alcohol-preferring rats in future research that seeks to obtain high levels of alcohol self-administration.

  10. 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

  11. Behavioral changes in preweaning and adult rats exposed prenatally to low ionizing radiation

    SciTech Connect

    Norton, S.

    1986-04-01

    Seven behavioral tests were used to evaluate the postnatal behavior of rats after exposure on gestational Day 15 to 0, 25, 50, 75, or 125 r, whole body irradiation of the pregnant rat. Three tests were administered in the first 2 postnatal weeks (righting reflex, negative geotaxis, and reflex suspension); three tests were administered on postnatal Day 21 (modified open field, spatial maze, and continuous corridor). As adults, the rats were retested with the same tests as at 21 days and also in the running wheel. Dose-response decreases in body weight were greater in the younger rats. Some behavioral tests were not altered by irradiation, while others showed clear dose-response relationships, starting as low as 25 r. The early changes were characterized by light body weight, delays in behavioral development and hypoactivity, followed by recovery of some parameters with maturation. Eventually hyperactivity developed in adult rats after gestational irradiation. However, it cannot be concluded that either morphological or behavioral tests are more sensitive than neonatal body weight change for detection of damage from gestational irradiation.

  12. Aging-Dependent Changes in the Radiation Response of the Adult Rat Brain

    SciTech Connect

    Schindler, Matthew K. Forbes, M. Elizabeth; Robbins, Mike E.; Riddle, David R.

    2008-03-01

    Purpose: To assess the impact of aging on the radiation response in the adult rat brain. Methods and Materials: Male rats 8, 18, or 28 months of age received a single 10-Gy dose of whole-brain irradiation (WBI). The hippocampal dentate gyrus was analyzed 1 and 10 weeks later for sensitive neurobiologic markers associated with radiation-induced damage: changes in density of proliferating cells, immature neurons, total microglia, and activated microglia. Results: A significant decrease in basal levels of proliferating cells and immature neurons and increased microglial activation occurred with normal aging. The WBI induced a transient increase in proliferation that was greater in older animals. This proliferation response did not increase the number of immature neurons, which decreased after WBI in young rats, but not in old rats. Total microglial numbers decreased after WBI at all ages, but microglial activation increased markedly, particularly in older animals. Conclusions: Age is an important factor to consider when investigating the radiation response of the brain. In contrast to young adults, older rats show no sustained decrease in number of immature neurons after WBI, but have a greater inflammatory response. The latter may have an enhanced role in the development of radiation-induced cognitive dysfunction in older individuals.

  13. Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity.

    PubMed

    van de Heijning, Bert J M; Kegler, Diane; Schipper, Lidewij; Voogd, Eline; Oosting, Annemarie; van der Beek, Eline M

    2015-07-08

    Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN) Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control). A 50%-75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed.

  14. Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity

    PubMed Central

    van de Heijning, Bert J. M.; Kegler, Diane; Schipper, Lidewij; Voogd, Eline; Oosting, Annemarie; van der Beek, Eline M.

    2015-01-01

    Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN) Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control). A 50%–75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed. PMID:26184291

  15. Prenatal Ethanol Exposure Increases Brain Cholesterol Content in Adult Rats

    PubMed Central

    Barceló-Coblijn, Gwendolyn; Wold, Loren E.; Ren, Jun; Murphy, Eric J.

    2013-01-01

    Fetal alcohol syndrome is the most severe expression of the fetal alcohol spectrum disorders (FASD). Although alterations in fetal and neonate brain fatty acid composition and cholesterol content is known to change in animal models of FASD, the persistence of these alterations into adulthood is unknown. To address this question, we determined the effect of prenatal ethanol exposure on individual phospholipid class fatty acid composition, individual phospholipid class mass, and cholesterol mass in brains from 25-week-old rats that were exposed to ethanol during gestation beginning at gestational day 2. While total phospholipid mass was unaffected, phosphatidylinositol and cardiolipin mass was decreased 14 and 43%, respectively. Exposure to prenatal ethanol modestly altered brain phospholipid fatty acid composition, and the most consistent change was a significant 1.1-fold increase in total PUFA, in the n-3/n-6 ratio, and in the 22:6 n-3 content in ethanolamine glycerophospholipids and in phosphatidylserine. In contrast, prenatal ethanol consumption significantly increased brain cholesterol mass 1.4-fold and the phospholipid to cholesterol ratio was significantly increased 1.3-fold. These results indicate that brain cholesterol mass was significantly increased in adult rats exposed prenatally to ethanol, but changes in phospholipid mass and phospholipid fatty acid composition were extremely limited. Importantly, suppression of post-natal ethanol consumption was not sufficient to reverse the large increase in cholesterol observed in the adult rats. PMID:23996454

  16. Optical spectroscopy of radiotherapy and photodynamic therapy responses in normal rat skin shows vascular breakdown products

    NASA Astrophysics Data System (ADS)

    Teles de Andrade, Cintia; Nogueira, Marcelo S.; Kanick, Stephen C.; Marra, Kayla; Gunn, Jason; Andreozzi, Jacqueline; Samkoe, Kimberley S.; Kurachi, Cristina; Pogue, Brian W.

    2016-03-01

    Photodynamic therapy (PDT) and radiotherapy are non-systemic cancer treatment options with different mechanisms of damage. So combining these techniques has been shown to have some synergy, and can mitigate their limitations such as low PDT light penetration or radiotherapy side effects. The present study monitored the induced tissue changes after PDT, radiotherapy, and a combination protocol in normal rat skin, using an optical spectroscopy system to track the observed biophysical changes. The Wistar rats were treated with one of the protocols: PDT followed by radiotherapy, PDT, radiotherapy and radiotherapy followed by PDT. Reflectance spectra were collected in order to observe the effects of these combined therapies, especially targeting vascular response. From the reflectance, information about oxygen saturation, met-hemoglobin and bilirubin concentration, blood volume fraction (BVF) and vessel radius were extracted from model fitting of the spectra. The rats were monitored for 24 hours after treatment. Results showed that there was no significant variation in the vessel size or BVF after the treatments. However, the PDT caused a significant increase in the met-hemoglobin and bilirubin concentrations, indicating an important blood breakdown. These results may provide an important clue on how the damage establishment takes place, helping to understand the effect of the combination of those techniques in order to verify the existence of a known synergistic effect.

  17. Dentate gyrus-specific knockdown of adult neurogenesis impairs spatial and object recognition memory in adult rats

    PubMed Central

    Jessberger, Sebastian; Clark, Robert E.; Broadbent, Nicola J.; Clemenson, Gregory D.; Consiglio, Antonella; Lie, D. Chichung; Squire, Larry R.; Gage, Fred H.

    2009-01-01

    New granule cells are born throughout life in the dentate gyrus of the hippocampal formation. Given the fundamental role of the hippocampus in processes underlying certain forms of learning and memory, it has been speculated that newborn granule cells contribute to cognition. However, previous strategies aiming to causally link newborn neurons with hippocampal function used ablation strategies that were not exclusive to the hippocampus or that were associated with substantial side effects, such as inflammation. We here used a lentiviral approach to specifically block neurogenesis in the dentate gyrus of adult male rats by inhibiting WNT signaling, which is critically involved in the generation of newborn neurons, using a dominant-negative WNT (dnWNT). We found a level-dependent effect of adult neurogenesis on the long-term retention of spatial memory in the water maze task, as rats with substantially reduced levels of newborn neurons showed less preference for the target zone in probe trials >2 wk after acquisition compared with control rats. Furthermore, animals with strongly reduced levels of neurogenesis were impaired in a hippocampus-dependent object recognition task. Social transmission of food preference, a behavioral test that also depends on hippocampal function, was not affected by knockdown of neurogenesis. Here we identified a role for newborn neurons in distinct aspects of hippocampal function that will set the ground to further elucidate, using experimental and computational strategies, the mechanism by which newborn neurons contribute to behavior. PMID:19181621

  18. Effects of Adolescent Ethanol Exposure on Sleep in Adults Rats

    PubMed Central

    Criado, José R.; Wills, Derek N.; Walker, Brendan M.; Ehlers, Cindy L.

    2010-01-01

    Although adolescent ethanol (EtOH) exposure has been associated with long-lasting changes in brain function, little is known as to whether EtOH exposure during adolescence alters sleep and cortical arousal. This study examined protracted alterations in sleep in adult rats exposed to EtOH during adolescence. Adolescent male Wistar rats were exposed to EtOH vapor for 12 hr/day for five weeks. Cortical electroencephalograms (EEGs) were obtained during 4-hr recording sessions after five weeks of withdrawal from EtOH. Adolescent EtOH exposure significantly reduced the mean duration of slow-wave sleep (SWS) episodes and the total amount of time spent in SWS in EtOH-exposed rats, compared to controls. Spectral analysis revealed that adolescent EtOH exposure significantly increased cortical peak frequencies during SWS in the 2-4 Hz, 4-6 Hz and 6-8 Hz bands. Taken together, our findings suggest that chronic EtOH exposure in adolescent rats reduces measures of SWS, an effect also seen as part of normal aging. Although the cellular and molecular mechanisms mediating the consequences of EtOH exposure on the aging process are not known, the similarities between adolescent EtOH exposure and aging merits further investigation. PMID:18922666

  19. Maternal hyperthyroidism in rats impairs stress coping of adult offspring.

    PubMed

    Zhang, Limei; Hernández, Vito S; Medina-Pizarro, Mauricio; Valle-Leija, Pablo; Vega-González, Arturo; Morales, Teresa

    2008-05-01

    Given the evidence that maternal hyperthyroidism (MH) compromises expression of neuronal cytoskeletal proteins in the late fetal brain by accelerated neuronal differentiation, we investigated possible consequences of MH for the emotional and cognitive functions of adult offspring during acute and subchronic stress coping. Experimental groups consisted of male rat offspring from mothers implanted with osmotic minipumps infusing either thyroxine (MH) or vehicle (Ctrl) during pregnancy. Body weight and T4 level were monitored during the first 3 postnatal months, and no differences were found with the controls. We analyzed hippocampal CA3 pyramidal neurons and dentate granular cell morphology during several postnatal stages and found increased dendritic arborization. On postnatal day 90 a modified subchronic mild stress (SCMS) protocol was applied to experimental subjects for 10 days. The Morris water maze was used before, during, and after application of the SCMS protocol to measure spatial learning. The tail suspension test (TST) and forced-swimming test (FST) were used to evaluate behavioral despair. The MH rats displayed normal locomotor activity and spatial memory prior to SCMS, but impaired spatial learning after acute and chronic stress. In both the FST and TST we found that MH rats spent significantly more time immobile than did controls. Serum corticosterone level was found to increase after 30 min of restraint stress, and corticotropin-releasing factor immunoreactivity was found to be increased in the central nucleus of the amygdala. Our results suggest that MH in rats leads to the offspring being more vulnerable to stress in adulthood.

  20. [Average values of electrocardiograph parameters in healthy, adult Wistar rats].

    PubMed

    Zaciragić, Asija; Nakas-ićindić, Emina; Hadzović, Almira; Avdagić, Nesina

    2004-01-01

    Average values of heart rate (HR) and the average duration of electrocardiograph parameters were investigated (RR interval, P wave, PQ interval, QRS complex and QT interval) in healthy, adult Wistar rats of both sexes (n=86). Electrocardiogram (ECG) was recorded by Shiller Resting ECG, and for analysis of recordings SEMA-200 Vet computer program was used. Prior to registration animals were exposed to light ether anesthesia. Mean value of HR was 203.03+/-3.09 beats/min in whole sample. Observed differences in mean values of heart rate and duration of followed ECG parameters between sexes were not statistically significant. Results gathered in our study could serve as standard values for electrocardiograph parameters in future research where will be used Wistar rats in conditions of registration and analysis of ECG that are described in our paper.

  1. Gender differences in the effect of adult amphetamine on cognitive functions of rats prenatally exposed to methamphetamine.

    PubMed

    Macúchová, E; Nohejlová, K; Slamberová, R

    2014-08-15

    Psychostimulants have been shown to affect brain regions involved in the process of learning and memory consolidation. It has been shown that females are more sensitive to the effects of drugs than males. The aim of our study was to investigate how prenatal methamphetamine (MA) exposure and application of amphetamine (AMP) in adulthood would affect spatial learning of adult female and male rats. Mothers of the tested offspring were exposed to injections of MA (5mg/kg) or saline (SA) throughout the entire gestation period. Cognitive functions of adult rats were evaluated in the Morris Water Maze (MWM) tests. Adult offspring were injected daily with AMP (5mg/kg) or SA through the period of MWM testing. Our data from the MWM tests demonstrates the following. Prenatal MA exposure did not change the learning ability of adult male and female rats. However, AMP administration to adult animals affected cognitive function in terms of exacerbation of spatial learning (increasing the latency to reach the hidden platform, the distance traveled and the search error) only in female subjects. There were sex differences in the speed of swimming. Prenatal MA exposure and adult AMP treatment increased the speed of swimming in female groups greater than in males. Overall, the male subjects showed a better learning ability than females. Thus, our results indicate that the adult AMP treatment affects the cognitive function and behavior of rats in a sex-specific manner, regardless of prenatal exposure.

  2. Place Cell Networks in Pre-weanling Rats Show Associative Memory Properties from the Onset of Exploratory Behavior

    PubMed Central

    Muessig, L.; Hauser, J.; Wills, T. J.; Cacucci, F.

    2016-01-01

    Place cells are hippocampal pyramidal cells that are active when an animal visits a restricted area of the environment, and collectively their activity constitutes a neural representation of space. Place cell populations in the adult rat hippocampus display fundamental properties consistent with an associative memory network: the ability to 1) generate new and distinct spatial firing patterns when encountering novel spatial contexts or changes in sensory input (“remapping”) and 2) reinstate previously stored firing patterns when encountering a familiar context, including on the basis of an incomplete/degraded set of sensory cues (“pattern completion”). To date, it is unknown when these spatial memory responses emerge during brain development. Here, we show that, from the age of first exploration (postnatal day 16) onwards, place cell populations already exhibit these key features: they generate new representations upon exposure to a novel context and can reactivate familiar representations on the basis of an incomplete set of sensory cues. These results demonstrate that, as early as exploratory behaviors emerge, and despite the absence of an adult-like grid cell network, the developing hippocampus processes incoming sensory information as an associative memory network. PMID:27282394

  3. Place Cell Networks in Pre-weanling Rats Show Associative Memory Properties from the Onset of Exploratory Behavior.

    PubMed

    Muessig, L; Hauser, J; Wills, T J; Cacucci, F

    2016-08-01

    Place cells are hippocampal pyramidal cells that are active when an animal visits a restricted area of the environment, and collectively their activity constitutes a neural representation of space. Place cell populations in the adult rat hippocampus display fundamental properties consistent with an associative memory network: the ability to 1) generate new and distinct spatial firing patterns when encountering novel spatial contexts or changes in sensory input ("remapping") and 2) reinstate previously stored firing patterns when encountering a familiar context, including on the basis of an incomplete/degraded set of sensory cues ("pattern completion"). To date, it is unknown when these spatial memory responses emerge during brain development. Here, we show that, from the age of first exploration (postnatal day 16) onwards, place cell populations already exhibit these key features: they generate new representations upon exposure to a novel context and can reactivate familiar representations on the basis of an incomplete set of sensory cues. These results demonstrate that, as early as exploratory behaviors emerge, and despite the absence of an adult-like grid cell network, the developing hippocampus processes incoming sensory information as an associative memory network. PMID:27282394

  4. Effects of estradiol and methoxychlor on Leydig cell regeneration in the adult rat testis.

    PubMed

    Chen, Bingbing; Chen, Dongxin; Jiang, Zheli; Li, Jingyang; Liu, Shiwen; Dong, Yaoyao; Yao, Wenwen; Akingbemi, Benson; Ge, Renshan; Li, Xiaokun

    2014-05-06

    The objective of the present study is to determine whether methoxychlor (MXC) exposure in adulthood affects rat Leydig cell regeneration and to compare its effects with estradiol (E2). Adult 90-day-old male Sprague-Dawley rats received ethane dimethane sulfonate (EDS) to eliminate the adult Leydig cell population. Subsequently, rats were randomly assigned to four groups and gavaged with corn oil (control), 0.25 mg/kg E2 and 10 or 100 mg/kg MXC daily from days 5 to 30 post-EDS treatment. The results showed that MXC and E2 reduced serum testosterone levels on day 58 post-EDS treatment. qPCR showed Hsd17b3 mRNA levels were downregulated 7-15 fold by E2 and MXC, indicating that development of the new population of Leydig cells was arrested at the earlier stage. This observation was supported by the results of histochemical staining, which demonstrated that Leydig cells in MXC-treated testis on day 58 post-EDS treatment were mostly progenitor Leydig cells. However, Pdgfb mRNA levels were downregulated, while Lif transcript levels were increased by MXC. In contrast, E2 did not affect gene expression for these growth factors. In conclusion, our findings indicated that both MXC and E2 delayed rat Leydig cell regeneration in the EDS-treated model, presumably acting by different mechanisms.

  5. Effects of Estradiol and Methoxychlor on Leydig Cell Regeneration in the Adult Rat Testis

    PubMed Central

    Chen, Bingbing; Chen, Dongxin; Jiang, Zheli; Li, Jingyang; Liu, Shiwen; Dong, Yaoyao; Yao, Wenwen; Akingbemi, Benson; Ge, Renshan; Li, Xiaokun

    2014-01-01

    The objective of the present study is to determine whether methoxychlor (MXC) exposure in adulthood affects rat Leydig cell regeneration and to compare its effects with estradiol (E2). Adult 90-day-old male Sprague-Dawley rats received ethane dimethane sulfonate (EDS) to eliminate the adult Leydig cell population. Subsequently, rats were randomly assigned to four groups and gavaged with corn oil (control), 0.25 mg/kg E2 and 10 or 100 mg/kg MXC daily from days 5 to 30 post-EDS treatment. The results showed that MXC and E2 reduced serum testosterone levels on day 58 post-EDS treatment. qPCR showed Hsd17b3 mRNA levels were downregulated 7–15 fold by E2 and MXC, indicating that development of the new population of Leydig cells was arrested at the earlier stage. This observation was supported by the results of histochemical staining, which demonstrated that Leydig cells in MXC-treated testis on day 58 post-EDS treatment were mostly progenitor Leydig cells. However, Pdgfb mRNA levels were downregulated, while Lif transcript levels were increased by MXC. In contrast, E2 did not affect gene expression for these growth factors. In conclusion, our findings indicated that both MXC and E2 delayed rat Leydig cell regeneration in the EDS-treated model, presumably acting by different mechanisms. PMID:24806340

  6. Perinatal thiamine restriction affects central GABA and glutamate concentrations and motor behavior of adult rat offspring.

    PubMed

    Ferreira-Vieira, Talita Hélen; de Freitas-Silva, Danielle Marra; Ribeiro, Andrea Frozino; Pereira, Sílvia Rejane Castanheira; Ribeiro, Ângela Maria

    2016-03-23

    The purposes of the present study were to investigate the effects of perinatal thiamine deficiency, from the 11th day of gestation until the 5th day of lactation, on motor behavior and neurochemical parameters in adult rat offspring, using 3-month-old, adult, male Wistar rats. All rats were submitted to motor tests, using the rotarod and paw print tasks. After behavioral tests, their thalamus, cerebellum and spinal cord were dissected for glutamate and GABA quantifications by high performance liquid chromatography. The thiamine-restricted mothers (RM) group showed a significant reduction of time spent on the rotarod at 25 rpm and an increase in hind-base width. A significant decrease of glutamate concentration in the cerebellum and an increase of GABA concentrations in the thalamus were also observed. For the offspring from control mothers (CM) group there were significant correlations between thalamic GABA concentrations and both rotarod performance and average hind-base width. In addition, for rats from the RM group a significant correlation between stride length and cerebellar GABA concentration was found. These results show that the deficiency of thiamine during an early developmental period affects certain motor behavior parameters and GABA and glutamate levels in specific brain areas. Hence, a thiamine deficiency episode during an early developmental period can induce motor impairments and excitatory and inhibitory neurotransmitter changes that are persistent and detectable in later periods of life. PMID:26836141

  7. Combination of Pitavastatin and melatonin shows partial antineoplastic effects in a rat breast carcinoma model.

    PubMed

    Kubatka, Peter; Bojková, Bianka; Kassayová, Monika; Orendáš, Peter; Kajo, Karol; Výbohová, Desanka; Kružliak, Peter; Adamicová, Katarína; Péč, Martin; Stollárová, Nadežda; Adamkov, Marián

    2014-10-01

    Our previous results indicated significant tumor-suppressive effects of different statins in rat mammary carcinogenesis. The purpose of this experiment was to examine the chemopreventive effects of Pitavastatin alone and in combination with the pineal hormone melatonin in the model of N-methyl-N-nitrosourea-induced mammary carcinogenesis in female Sprague-Dawley rats. Pitavastatin was administered dietary (10mg/kg) and melatonin in an aqueous solution (20μg/ml). Chemoprevention began 7 days prior to carcinogen administration and subsequently continued for 15 weeks until autopsy. At autopsy, mammary tumors were removed and prepared for histopathological and immunohistochemical analysis. Compared to controls, Pitavastatin alone reduced average tumor volume by 58% and lengthened latency by 8 days; on the other hand, the drug increased tumor frequency by 23%. Combined administration of Pitavastatin with melatonin decreased tumor frequency by 23%, tumor volume by 44% and lengthened tumor latency by 5.5 days compared to control animals. The analysis of carcinoma cells showed significant increase in caspase-3 expression in both treated groups and a tendency of increased caspase-7 expression after Pitavastatin treatment alone. Significant expression decrease of Ki67 was found in carcinoma cells from both treated groups. Compared to control carcinoma cells, Pitavastatin alone increased VEGF expression by 41%, however melatonin totally reversed its undesirable effect. Pitavastatin combined with melatonin significantly increased femur compact bone thickness in animals. Pitavastatin alone decreased plasma triglycerides and total cholesterol levels, however it significantly increased levels of glucose. In summary, our results show a partial antineoplastic effect of Pitavastatin combined with melatonin in the rat mammary gland carcinoma model. PMID:25450902

  8. Alcohol-Preferring Rats Show Goal Oriented Behaviour to Food Incentives but Are Neither Sign-Trackers Nor Impulsive

    PubMed Central

    Peña-Oliver, Yolanda; Giuliano, Chiara; Goodlett, Charles R.; Robbins, Trevor W.; Dalley, Jeffrey W.; Everitt, Barry J.

    2015-01-01

    Drug addiction is often associated with impulsivity and altered behavioural responses to both primary and conditioned rewards. Here we investigated whether selectively bred alcohol-preferring (P) and alcohol-nonpreferring (NP) rats show differential levels of impulsivity and conditioned behavioural responses to food incentives. P and NP rats were assessed for impulsivity in the 5-choice serial reaction time task (5-CSRTT), a widely used translational task in humans and other animals, as well as Pavlovian conditioned approach to measure sign- and goal-tracking behaviour. Drug-naïve P and NP rats showed similar levels of impulsivity on the 5-CSRTT, assessed by the number of premature, anticipatory responses, even when the waiting interval to respond was increased. However, unlike NP rats, P rats were faster to enter the food magazine and spent more time in this area. In addition, P rats showed higher levels of goal-tracking responses than NP rats, as measured by the number of magazine nose-pokes during the presentation of a food conditioned stimulus. By contrast, NP showed higher levels of sign-tracking behaviour than P rats. Following a 4-week exposure to intermittent alcohol we confirmed that P rats had a marked preference for, and consumed more alcohol than, NP rats, but were not more impulsive when re-tested in the 5-CSRTT. These findings indicate that high alcohol preferring and drinking P rats are neither intrinsically impulsive nor do they exhibit impulsivity after exposure to alcohol. However, P rats do show increased goal-directed behaviour to food incentives and this may be associated with their strong preference for alcohol. PMID:26098361

  9. Alcohol-Preferring Rats Show Goal Oriented Behaviour to Food Incentives but Are Neither Sign-Trackers Nor Impulsive.

    PubMed

    Peña-Oliver, Yolanda; Giuliano, Chiara; Economidou, Daina; Goodlett, Charles R; Robbins, Trevor W; Dalley, Jeffrey W; Everitt, Barry J

    2015-01-01

    Drug addiction is often associated with impulsivity and altered behavioural responses to both primary and conditioned rewards. Here we investigated whether selectively bred alcohol-preferring (P) and alcohol-nonpreferring (NP) rats show differential levels of impulsivity and conditioned behavioural responses to food incentives. P and NP rats were assessed for impulsivity in the 5-choice serial reaction time task (5-CSRTT), a widely used translational task in humans and other animals, as well as Pavlovian conditioned approach to measure sign- and goal-tracking behaviour. Drug-naïve P and NP rats showed similar levels of impulsivity on the 5-CSRTT, assessed by the number of premature, anticipatory responses, even when the waiting interval to respond was increased. However, unlike NP rats, P rats were faster to enter the food magazine and spent more time in this area. In addition, P rats showed higher levels of goal-tracking responses than NP rats, as measured by the number of magazine nose-pokes during the presentation of a food conditioned stimulus. By contrast, NP showed higher levels of sign-tracking behaviour than P rats. Following a 4-week exposure to intermittent alcohol we confirmed that P rats had a marked preference for, and consumed more alcohol than, NP rats, but were not more impulsive when re-tested in the 5-CSRTT. These findings indicate that high alcohol preferring and drinking P rats are neither intrinsically impulsive nor do they exhibit impulsivity after exposure to alcohol. However, P rats do show increased goal-directed behaviour to food incentives and this may be associated with their strong preference for alcohol. PMID:26098361

  10. Alcohol exposure in utero perturbs retinoid homeostasis in adult rats

    PubMed Central

    Kim, Youn-Kyung; Zuccaro, Michael V.; Zhang, Changqing; Sarkar, Dipak

    2015-01-01

    Background Maternal alcohol exposure and adult alcohol intake have been shown to perturb the metabolism of various micro- and macro-nutrients, including vitamin A and its derivatives (retinoids). Therefore, it has been hypothesized that the well-known detrimental consequences of alcohol consumption may be due to deregulations of the metabolism of such nutrients rather than to a direct effect of alcohol. Alcohol exposure in utero also has long-term harmful consequences on the health of the offspring with mechanisms that have not been fully clarified. Disruption of tissue retinoid homeostasis has been linked not only to abnormal embryonic development, but also to various adult pathological conditions, including cancer, metabolic disorders and abnormal lung function. We hypothesized that prenatal alcohol exposure may permanently perturb tissue retinoid metabolism, predisposing the offspring to adult chronic diseases. Methods Serum and tissues (liver, lung and prostate from males; liver and lung from females) were collected from 60-75 day-old sprague dawley rats born from dams that were: (I) fed a liquid diet containing 6.7% alcohol between gestational day 7 and 21; or (II) pair-fed with isocaloric liquid diet during the same gestational window; or (III) fed ad libitum with regular rat chow diet throughout pregnancy. Serum and tissue retinoid levels were analyzed by reverse-phase high-performance liquid chromatography (HPLC). Serum retinol-binding protein (RBP) levels were measured by western blot analysis, and liver, lung and prostate mRNA levels of lecithin-retinol acyltransferase (LRAT) were measured by qPCR. Results Retinyl ester levels were significantly reduced in the lung of both males and females, as well as in the liver and ventral prostate of males born from alcohol-fed dams. Tissue LRAT mRNA levels remained unchanged upon maternal alcohol treatment. Conclusions Prenatal alcohol exposure in rats affects retinoid metabolism in adult life, in a tissue- and sex

  11. Female rats exposed to stress and alcohol show impaired memory and increased depressive-like behaviors.

    PubMed

    Gomez, J L; Luine, V N

    2014-01-17

    Exposure to daily life stressors is associated with increases in anxiety, depression, and overall negative affect. Alcohol or other psychoactive drugs are often used to alleviate stress effects. While females are more than twice as likely to develop mood disorders and are more susceptible to dependency than males, they are infrequently examined. In this study, female rats received no stress/no alcohol control (CON), alcohol alone (ALC), stress alone (STR), or stress plus alcohol (STR+ALC). Stress consisted of restraint for 6h/day/7days, and alcohol was administered immediately following restraint via gastric gavage at a dose of 2.0g/kg. Dependent measures included tests utilizing object recognition (OR), Y-maze, elevated plus maze (EPM), forced swim (FST), blood alcohol content, corticosterone levels, and body weights. ALC, STR+ALC, but not stress alone, impaired memory on OR. All treatments impaired spatial memory on the Y-maze. Anxiety was not affected on the EPM, but rats treated with alcohol or in combination with stress showed increased immobility on the FST, suggestive of alcohol-induced depression. Previously, we found alcohol reversed deleterious effects of stress on memory and mood in males, but current results show that females reacted negatively when the two treatments were combined. Thus, responses to alcohol, stress and their combination suggest that sex specific treatments are needed for stress-induced behavioral changes and that self-medicating with alcohol to cope with stress maybe deleterious in females.

  12. Female Rats Exposed to Stress and Alcohol Show Impaired Memory and Increased Depressive-like Behaviors

    PubMed Central

    Gomez, J.L.; Luine, V.N.

    2013-01-01

    Exposure to daily life stressors is associated with increases in anxiety, depression, and overall negative affect. Alcohol or other psychoactive drugs are often used to alleviate stress effects. While females are more than twice as likely to develop mood disorders and are more susceptible to dependency than males, they are infrequently examined. In this study, female rats received no stress/no alcohol control (CON), alcohol alone (ALC), stress alone (STR), or stress plus alcohol (STR+ALC). Stress consisted of restraint for 6hr/day/7days, and alcohol was administered immediately following restraint via gastric gavage at a dose of 2.0 g/kg. Dependent measures included tests utilizing object recognition (OR), Y-maze, elevated plus maze (EPM), forced swim (FST), blood alcohol content, corticosterone levels, and body weights. ALC, STR+ALC, but not stress alone, impaired memory on OR. All treatments impaired spatial memory on the Y-maze. Anxiety was not affected on the EPM, but rats treated with alcohol or in combination with stress showed increased immobility on the FST, suggestive of alcohol-induced depression. Previously, we found alcohol reversed deleterious effects of stress on memory and mood in males, but current results show females reacted negatively when the two treatments were combined. Thus, responses to alcohol, stress and their combination suggest that sex specific treatments are needed for stress-induced behavioral changes and that self-medicating with alcohol to cope with stress maybe deleterious in females. PMID:24096191

  13. A spaceflight study of synaptic plasticity in adult rat vestibular maculas

    NASA Technical Reports Server (NTRS)

    Ross, M. D.

    1994-01-01

    Behavioral signs of vestibular perturbation in altered gravity have not been well correlated with structural modifications in neurovestibular centers. This ultrastructural research investigated synaptic plasticity in hair cells of adult rat utricular maculas exposed to microgravity for nine days on a space shuttle. The hypothesis was that synaptic plasticity would be more evident in type II hair cells because they are part of a distributed modifying macular circuitry. All rats were shared with other investigators and were subjected to treatments unrelated to this experiment. Maculas were obtained from flight and control rats after shuttle return (R + 0) and nine days post-flight (R + 9). R + 9 rats had chromodacryorrhea, a sign of acute stress. Tissues were prepared for ultrastructural study by conventional methods. Ribbon synapses were counted in fifty serial sections from medial utricular macular regions of three rats of each flight and control group. Counts in fifty additional consecutive sections from one sample in each group established method reliability. All synapses were photographed and located to specific cells on mosaics of entire sections. Pooled data were analyzed statistically. Flown rats showed abnormal posture and movement at R + 0. They had statistically significant increases in total ribbon synapses and in sphere-like ribbons in both kinds of hair cells; in type II cells, pairs of synapses nearly doubled and clusters of 3 to 6 synapses increased twelve-fold. At R + 9, behavioral signs were normal. However, synapse counts remained high in both kinds of hair cells of flight maculas and were elevated in control type II cells. Only counts in type I cells showed statistically significant differences at R + 9. High synaptic counts at R + 9 may have resulted from stress due to experimental treatments. The results nevertheless demonstrate that adult maculas retain the potential for synaptic plasticity. Type II cells exhibited more synaptic plasticity, but

  14. Sacral chordoma in an adult showing an aggressive clinical course: A case report

    PubMed Central

    ENDO, KOJI; YAMASHITA, HIDEKI; NAGASHIMA, HIDEKI; TESHIMA, RYOTA

    2014-01-01

    The current report presents a case of a 78-year-old male with sacral chordoma, showing an aggressive clinical course. The patient underwent sacral resection, however, nine months later, multiple metastases were detected by magnetic resonance imaging. The metastases progressed rapidly and 15 months following surgery the patient succumbed to respiratory dysfunction. An autopsy revealed multiple metastases of the lung, liver, heart, kidneys and vertebrae. Pathologically, the tumors did not show proliferation of anaplastic cells or dedifferentiation; however, the metastatic tumor cells were smaller than the primary tumor cells. The Ki-67 labeling indices were <5% in all of the patient’s tumors, therefore, the capacity for cellular proliferation of the tumors was considered to be low. Chordoma in adults are generally slow-growing tumors and are associated with a relatively prolonged course and frequent local recurrences. Therefore, it must be recognized that chordoma may grow rapidly and show an aggressive clinical course, even when the Ki-67 labeling index is low. PMID:24765153

  15. Rat retina shows robust circadian expression of clock and clock output genes in explant culture

    PubMed Central

    Buonfiglio, Daniella C.; Malan, André; Sandu, Cristina; Jaeger, Catherine; Cipolla-Neto, José; Hicks, David

    2014-01-01

    Purpose Circadian rhythms are central to vision and retinal physiology. A circadian clock located within the retina controls various rhythmic processes including melatonin synthesis in photoreceptors. In the present study, we evaluated the rhythmic expression of clock genes and clock output genes in retinal explants maintained for several days in darkness. Methods Retinas were dissected from Wistar rats, either wild-type or from the Per1-luciferase transgenic line housed under a daily 12 h:12 h light-dark cycle (LD12/12), and put in culture at zeitgeber time (ZT) 12 on semipermeable membranes. Explants from wild-type rats were collected every 4 h over 3 days, and total RNA was extracted, quantified, and reverse transcribed. Gene expression was assessed with quantitative PCR, and the periodicity of the relative mRNA amounts was assessed with nonlinear least squares fitting to sine wave functions. Bioluminescence in explants from Per1-luciferase rats was monitored for several days under three different culture protocols. Results Rhythmic expression was found for all studied clock genes and for clock downstream targets such as c-fos and arylalkylamine N-acetyltransferase (Aanat) genes. Clock and output genes cycled with relatively similar periods and acrophases (peaks of expression during subjective night, except c-fos, which peaked around the end of the subjective day). Data for Per1 were confirmed with bioluminescence monitoring, which also permitted culture conditions to be optimized to study the retina clock. Conclusions Our work shows the free-running expression profile of multiple clock genes and potential clock targets in mammalian retinal explants. This research further strengthens the notion that the retina contains a self-sustained oscillator that can be functionally characterized in organotypic culture. PMID:24940028

  16. Nickel nanoparticles exposure and reproductive toxicity in healthy adult rats.

    PubMed

    Kong, Lu; Tang, Meng; Zhang, Ting; Wang, Dayong; Hu, Ke; Lu, Weiqi; Wei, Chao; Liang, Geyu; Pu, Yuepu

    2014-01-01

    Nickel is associated with reproductive toxicity. However, the reproductive toxicity of nickel nanoparticles (Ni NPs) is unclear. Our goal was to determine the association between nickel nanoparticle exposure and reproductive toxicity. According to the one-generation reproductive toxicity standard, rats were exposed to nickel nanoparticles by gavage and we selected indicators including sex hormone levels, sperm motility, histopathology, and reproductive outcome etc. Experimental results showed nickel nanoparticles increased follicle stimulating hormone (FSH) and luteinizing hormone (LH), and lowered etradiol (E2) serum levels at a dose of 15 and 45 mg/kg in female rats. Ovarian lymphocytosis, vascular dilatation and congestion, inflammatory cell infiltration, and increase in apoptotic cells were found in ovary tissues in exposure groups. For male rats, the weights decreased gradually, the ratio of epididymis weight over body weight increased, the motility of rat sperm changed, and the levels of FSH and testosterone (T) diminished. Pathological results showed the shedding of epithelial cells of raw seminiferous tubule, disordered arrangement of cells in the tube, and the appearance of cell apoptosis and death in the exposure group. At the same time, Ni NPs resulted in a change of the reproductive index and the offspring development of rats. Further research is needed to elucidate exposure to human populations and mechanism of actions. PMID:25407529

  17. Nickel Nanoparticles Exposure and Reproductive Toxicity in Healthy Adult Rats

    PubMed Central

    Kong, Lu; Tang, Meng; Zhang, Ting; Wang, Dayong; Hu, Ke; Lu, Weiqi; Wei, Chao; Liang, Geyu; Pu, Yuepu

    2014-01-01

    Nickel is associated with reproductive toxicity. However, the reproductive toxicity of nickel nanoparticles (Ni NPs) is unclear. Our goal was to determine the association between nickel nanoparticle exposure and reproductive toxicity. According to the one-generation reproductive toxicity standard, rats were exposed to nickel nanoparticles by gavage and we selected indicators including sex hormone levels, sperm motility, histopathology, and reproductive outcome etc. Experimental results showed nickel nanoparticles increased follicle stimulating hormone (FSH) and luteinizing hormone (LH), and lowered etradiol (E2) serum levels at a dose of 15 and 45 mg/kg in female rats. Ovarian lymphocytosis, vascular dilatation and congestion, inflammatory cell infiltration, and increase in apoptotic cells were found in ovary tissues in exposure groups. For male rats, the weights decreased gradually, the ratio of epididymis weight over body weight increased, the motility of rat sperm changed, and the levels of FSH and testosterone (T) diminished. Pathological results showed the shedding of epithelial cells of raw seminiferous tubule, disordered arrangement of cells in the tube, and the appearance of cell apoptosis and death in the exposure group. At the same time, Ni NPs resulted in a change of the reproductive index and the offspring development of rats. Further research is needed to elucidate exposure to human populations and mechanism of actions. PMID:25407529

  18. Myogenic regulatory factors during regeneration of skeletal muscle in young, adult, and old rats

    NASA Technical Reports Server (NTRS)

    Marsh, D. R.; Criswell, D. S.; Carson, J. A.; Booth, F. W.

    1997-01-01

    Myogenic factor mRNA expression was examined during muscle regeneration after bupivacaine injection in Fischer 344/Brown Norway F1 rats aged 3, 18, and 31 mo of age (young, adult, and old, respectively). Mass of the tibialis anterior muscle in the young rats had recovered to control values by 21 days postbupivacaine injection but in adult and old rats remained 40% less than that of contralateral controls at 21 and 28 days of recovery. During muscle regeneration, myogenin mRNA was significantly increased in muscles of young, adult, and old rats 5 days after bupivacaine injection. Subsequently, myogenin mRNA levels in young rat muscle decreased to postinjection control values by day 21 but did not return to control values in 28-day regenerating muscles of adult and old rats. The expression of MyoD mRNA was also increased in muscles at day 5 of regeneration in young, adult, and old rats, decreased to control levels by day 14 in young and adult rats, and remained elevated in the old rats for 28 days. In summary, either a diminished ability to downregulate myogenin and MyoD mRNAs in regenerating muscle occurs in old rat muscles, or the continuing myogenic effort includes elevated expression of these mRNAs.

  19. Developmental Vitamin D3 deficiency alters the adult rat brain.

    PubMed

    Féron, F; Burne, T H J; Brown, J; Smith, E; McGrath, J J; Mackay-Sim, A; Eyles, D W

    2005-03-15

    There is growing evidence that Vitamin D(3) (1,25-dihydroxyvitamin D(3)) is involved in brain development. We have recently shown that the brains of newborn rats from Vitamin D(3) deficient dams were larger than controls, had increased cell proliferation, larger lateral ventricles, and reduced cortical thickness. Brains from these animals also had reduced expression of nerve growth factor (NGF) and glial cell line-derived neurotrophic factor. The aim of the current study was to examine if there were any permanent outcomes into adulthood when the offspring of Vitamin D(3) deficient dams were restored to a normal diet. The brains of adult rats were examined at 10 weeks of age after Vitamin D(3) deficiency until birth or weaning. Compared to controls animals that were exposed to transient early Vitamin D(3) deficiency had larger lateral ventricles, reduced NGF protein content, and reduced expression of a number genes involved in neuronal structure, i.e. neurofilament or MAP-2 or neurotransmission, i.e. GABA-A(alpha4). We conclude that transient early life hypovitaminosis D(3) not only disrupts brain development but leads to persistent changes in the adult brain. In light of the high incidence of hypovitaminosis D(3) in women of child-bearing age, the public health implications of these findings warrant attention. PMID:15763180

  20. Perfluorooctane sulfonate effects on the reproductive axis in adult male rats.

    PubMed

    López-Doval, S; Salgado, R; Pereiro, N; Moyano, R; Lafuente, A

    2014-10-01

    Perfluorooctane sulfonate (PFOS) is a neurotoxic agent and it can disrupt the endocrine system activity. This work was undertaken to evaluate the possible effects of PFOS exposure on the hypothalamic-pituitary-testicular axis (HPT) in adult male rats, and to evaluate the possible morphological alterations induced by PFOS in the endocrine tissues of this axis. Adult male rats were orally treated with 0.5; 1.0; 3.0 and 6.0 mg of PFOS/kg/day for 28 days. After PFOS exposure, hypothalamic noradrenaline concentration increased in the anterior hypothalamus and in the median eminence, not changing in the mediobasal hypothalamus. PFOS treated rats presented a decrease of the gonadotropin releasing hormone (GnRH) gene expression, increasing the mRNA levels of the luteinizing hormone (LH) in rats treated with all doses administered except with the dose of 6 mg/kg/day. PFOS also induced a raise of the follicle stimulating hormone (FSH) gene expression in the animals exposed to 0.5 and 1.0 mg of PFOS/kg/day. After PFOS exposure, hypothalamic GnRH concentration was modified, LH and testosterone release was inhibited and FSH secretion was stimulated. Moreover, PFOS induced several histopathological alterations in the hypothalamus, pituitary gland and testis. The results obtained in the present study suggest in general terms that PFOS can inhibit the physiological activity of the reproductive axis in adult male rats, which could be explained, at least in part, by the structural alterations showed in the animals exposed to this chemical: very dense chromatin, condensed ribosomes and a loss of the morphology in the hypothalamus; a degeneration of the gonadotrophic cells, as well as a loss and degeneration of the spermatozoids and a very marked edema in the testis.

  1. Basic fibroblast growth factor protects against excitotoxicity and chemical hypoxia in both neonatal and adult rats.

    PubMed

    Kirschner, P B; Henshaw, R; Weise, J; Trubetskoy, V; Finklestein, S; Schulz, J B; Beal, M F

    1995-07-01

    Basic fibroblast growth factor (bFGF) is a polypeptide growth factor that promotes neuronal survival. We recently found that systemic administration of bFGF protects against both excitotoxicity and hypoxia-ischemia in neonatal animals. In the present study, we examined whether systemically administered bFGF could prevent neuronal death induced by intrastriatal injection of N-methyl-D-aspartate (NMDA) or chemical hypoxia induced by intrastriatal injection of malonate in adult rats and 1-methyl-4-phenylpyridinium (MPP+) in neonatal rats. Systemic administration of bFGF (100 micrograms/kg) for three doses both before and after intrastriatal injection of either NMDA or malonate in adult rats produced a significant neuroprotective effect. In neonatal rats, bFGF produced dose-dependent significant neuroprotective effects against MPP+ neurotoxicity, with a maximal protection of approximately 50% seen with either a single dose of bFGF of 300 micrograms/kg or three doses of 100 micrograms/kg. These results show that systemic administration of bFGF is effective in preventing neuronal injury under circumstances in which the blood-brain barrier may be compromised, raising the possibility that this strategy could be effective in stroke.

  2. Acute behavioral toxicity of carbaryl and propoxur in adult rats.

    PubMed

    Ruppert, P H; Cook, L L; Dean, K F; Reiter, L W

    1983-04-01

    Motor activity and neuromotor function were examined in adult CD rats exposed to either carbaryl or propoxur, and behavioral effects were compared with the time course of cholinesterase inhibition. Rats received an IP injection of either 0, 2, 4, 6 or 8 mg/kg propoxur or 0, 4, 8, 16 or 28 mg/kg carbaryl in corn oil 20 min before testing. All doses of propoxur reduced 2 hr activity in a figure-eight maze, and crossovers and rears in an open field. For carbaryl, dosages of 8, 16 and 28 mg/kg decreased maze activity whereas 16 and 28 mg/kg reduced open field activity. In order to determine the time course of effects, rats received a single IP injection of either corn oil, 2 mg/kg propoxur or 16 mg/kg carbaryl, and were tested for 5 min in a figure-eight maze either 15, 30, 60, 120 or 240 min post-injection. Immediately after testing, animals were sacrificed and total cholinesterase was measured. Maximum effects of propoxur and carbaryl on blood and brain cholinesterase and motor activity were seen within 15 min. Maze activity had returned to control levels within 30 and 60 min whereas cholinesterase levels remained depressed for 120 and 240 min for propoxur and carbaryl, respectively. These results indicate that both carbamates decrease motor activity, but behavioral recovery occurs prior to that of cholinesterase following acute exposure.

  3. Effect of exposure to diazinon on adult rat's brain.

    PubMed

    Rashedinia, Marzieh; Hosseinzadeh, Hossein; Imenshahidi, Mohsen; Lari, Parisa; Razavi, Bibi Marjan; Abnous, Khalil

    2016-04-01

    Diazinon (DZN), a commonly used agricultural organophosphate insecticide, is one of the major concerns for human health. This study was planned to investigate neurotoxic effects of subacute exposure to DZN in adult male Wistar rats. Animals received corn oil as control and 15 and 30 mg/kg DZN orally by gastric gavage for 4 weeks. The cerebrum malondialdehyde and glutathione (GSH) contents were assessed as biomarkers of lipid peroxidation and nonenzyme antioxidants, respectively. Moreover, activated forms of caspase 3, -9, and Bax/Bcl-2 ratios were evaluated as key apoptotic proteins. Results of this study suggested that chronic administration of DZN did not change lipid peroxidation and GSH levels significantly in comparison with control. Also, the active forms of caspase 3 and caspase 9 were not significantly altered in DZN-treated rat groups. Moreover, no significant changes were observed in Bax and Bcl-2 ratios. This study indicated that generation of reactive oxygen species was probably modulated by intracellular antioxidant system. In conclusion, subacute oral administration of DZN did not alter lipid peroxidation. Moreover, apoptosis induction was not observed in rat brain.

  4. Testosterone potentiates the hypoxic ventilatory response of adult male rats subjected to neonatal stress.

    PubMed

    Fournier, Sébastien; Gulemetova, Roumiana; Joseph, Vincent; Kinkead, Richard

    2014-05-01

    Neonatal stress disrupts development of homeostatic systems. During adulthood, male rats subjected to neonatal maternal separation (NMS) are hypertensive and show a larger hypoxic ventilatory response (HVR), with greater respiratory instability during sleep. Neonatal stress also affects sex hormone secretion; hypoxia increases circulating testosterone of NMS (but not control) male rats. Given that these effects of NMS are not observed in females, we tested the hypothesis that testosterone elevation is necessary for the stress-related increase of the HVR in adult male rats. Pups subjected to NMS were placed in an incubator for 3 h per day from postnatal day 3 to 12. Control pups remained undisturbed. Rats were reared until adulthood, and the HVR was measured by plethysmography (fractional inspired O2 = 0.12, for 20 min). We used gonadectomy to evaluate the effects of reducing testosterone on the HVR. Gonadectomy had no effect on the HVR of control animals but reduced that of NMS animals below control levels. Immunohistochemistry was used to quantify androgen receptors in brainstem areas involved in the HVR. Androgen receptor expression was generally greater in NMS rats than in control rats; the most significant increase was noted in the caudal region of the nucleus tractus solitarii. We conclude that the abnormal regulation of testosterone is important in stress-related augmentation of the HVR. The greater number of androgen receptors within the brainstem may explain why NMS rats are more sensitive to testosterone withdrawal. Based on the similarities of the cardiorespiratory phenotype of NMS rats and patients suffering from sleep-disordered breathing, these results provide new insight into its pathophysiology, especially sex-based differences in its prevalence.

  5. Use of the light/dark test for anxiety in adult and adolescent male rats.

    PubMed

    Arrant, Andrew E; Schramm-Sapyta, Nicole L; Kuhn, Cynthia M

    2013-11-01

    The light/dark (LD) test is a commonly used rodent test of unconditioned anxiety-like behavior that is based on an approach/avoidance conflict between the drive to explore novel areas and an aversion to brightly lit, open spaces. We used the LD test to investigate developmental differences in behavior between adolescent (postnatal day (PN) 28-34) and adult (PN67-74) male rats. We investigated whether LD behavioral measures reflect anxiety-like behavior similarly in each age group using factor analysis and multiple regression. These analyses showed that time in the light compartment, percent distance in the light, rearing, and latency to emerge into the light compartment were measures of anxiety-like behavior in each age group, while total distance traveled and distance in the dark compartment provided indices of locomotor activity. We then used these measures to assess developmental differences in baseline LD behavior and the response to anxiogenic drugs. Adolescent rats emerged into the light compartment more quickly than adults and made fewer pokes into the light compartment. These age differences could reflect greater risk taking and less risk assessment in adolescent rats than adults. Adolescent rats were less sensitive than adults to the anxiogenic effects of the benzodiazepine inverse agonist N-methyl-β-carboline-3-carboxamide (FG-7142) and the α₂ adrenergic antagonist yohimbine on anxiety-like behaviors validated by factor analysis, but locomotor variables were similarly affected. These data support the results of the factor analysis and indicate that GABAergic and noradrenergic modulation of LD anxiety-like behavior may be immature during adolescence.

  6. Ablating adult neurogenesis in the rat has no effect on spatial processing: evidence from a novel pharmacogenetic model.

    PubMed

    Groves, James O; Leslie, Isla; Huang, Guo-Jen; McHugh, Stephen B; Taylor, Amy; Mott, Richard; Munafò, Marcus; Bannerman, David M; Flint, Jonathan

    2013-01-01

    The function of adult neurogenesis in the rodent brain remains unclear. Ablation of adult born neurons has yielded conflicting results about emotional and cognitive impairments. One hypothesis is that adult neurogenesis in the hippocampus enables spatial pattern separation, allowing animals to distinguish between similar stimuli. We investigated whether spatial pattern separation and other putative hippocampal functions of adult neurogenesis were altered in a novel genetic model of neurogenesis ablation in the rat. In rats engineered to express thymidine kinase (TK) from a promoter of the rat glial fibrillary acidic protein (GFAP), ganciclovir treatment reduced new neurons by 98%. GFAP-TK rats showed no significant difference from controls in spatial pattern separation on the radial maze, spatial learning in the water maze, contextual or cued fear conditioning. Meta-analysis of all published studies found no significant effects for ablation of adult neurogenesis on spatial memory, cue conditioning or ethological measures of anxiety. An effect on contextual freezing was significant at a threshold of 5% (P = 0.04), but not at a threshold corrected for multiple testing. The meta-analysis revealed remarkably high levels of heterogeneity among studies of hippocampal function. The source of this heterogeneity remains unclear and poses a challenge for studies of the function of adult neurogenesis. PMID:24039591

  7. Older Adults Show Deficits in Retrieving and Decoding Associative Mediators Generated at Study

    ERIC Educational Resources Information Center

    Hertzog, Christopher; Fulton, Erika K.; Mandviwala, Lulua; Dunlosky, John

    2013-01-01

    We instructed the use of mediators to encode paired-associate items, and then measured both cued recall of targets and mediators. Older adults (n = 49) and younger adults (n = 57) studied a mixed list of concrete and abstract noun pairs under instructions to either generate a sentence or an image to form a new association between normatively…

  8. Novel alternative splice variants of rat phosphodiesterase 7B showing unique tissue-specific expression and phosphorylation.

    PubMed Central

    Sasaki, Takashi; Kotera, Jun; Omori, Kenji

    2002-01-01

    cDNA species coding for novel variants of cyclic-AMP-specific phosphodiesterases (PDEs), namely the PDE7B family, were isolated from rats and characterized. Rat PDE7B1 (RNPDE7B1) was composed of 446 amino acid residues. Rat PDE7B2 (RNPDE7B2) and PDE7B3 (RNPDE7B3), which possessed unique N-terminal sequences, consisted of 359 and 459 residues respectively. Northern hybridization analysis showed that rat PDE7B transcripts were particularly abundant in the striatum and testis. PCR analyses revealed that rat PDE7B2 transcripts were restricted to the testis and that low levels of PDE7B3 transcripts were expressed in the heart, lung and skeletal muscle. In situ hybridization analysis demonstrated that rat PDE7B transcripts were expressed in striatal neurons and spermatocytes. In spermatocytes, rat PDE7B transcripts were expressed in a stage-specific manner during spermatogenesis. The K(m) values of recombinant rat PDE7B1, PDE7B2 and PDE7B3 for cAMP were 0.05, 0.07 and 0.05 microM respectively. Each rat PDE7B variant was the most sensitive to 3-isobutyl-1-methylxanthine (IC(50) 1.5-2.1 microM). Two phosphorylation sites for cAMP-dependent protein kinase (PKA) were found in rat PDE7B1 and PDE7B3, whereas rat PDE7B2 possessed one site. PKA-dependent phosphorylation was observed in C-terminal phosphorylation sites of three rat PDE7B variants, in addition to unique N-terminal regions of rat PDE7B1 and PDE7B3. Unique tissue distribution and PKA-dependent phosphorylation of PDE7B variants suggested that each variant has a specific role for cellular functions via cAMP signalling in various tissues. PMID:11772393

  9. The longitudinal study of rat hippocampus influenced by stress: early adverse experience enhances hippocampal vulnerability and working memory deficit in adult rats.

    PubMed

    Jin, Fengkui; Li, Lei; Shi, Mei; Li, Zhenzi; Zhou, Jinghua; Chen, Li

    2013-06-01

    Epidemiologic studies indicate that early adverse experience is related to learning disabilities in adults, but the neurobiological mechanisms have not yet been identified. We used longitudinal animal experiments to test the hypothesis that early life stress enhances hippocampal vulnerability and working memory deficit in adult rats. The expression of Synaptophysin (SYN) and apoptosis (Apo) in hippocampal CA3 and dentate gyrus (DG) regions were examined to evaluate the effects of environmental factors on the hippocampus. The working memory errors via radial 8-arm maze were studied to evaluate the long-term effect of early stress on rats' spatial learning ability. Our results indicated that chronic restraint stress in early life and forced cold water swimming stress in adulthood reduced SYN expression and increased Apo levels in rat hippocampus, but the hippocampal damage tended to recover when rats returned to a non-stress environment. In addition, when the rats were exposed to forced cold water swimming stress during adulthood, SYN expression (CA3 and DG regions) and Apo levels (CA3 region) in rat hippocampus showed statistical difference between early restraint stress group and non-early restraint stress group (rats exposed to stress in adulthood only). One month after the two groups of rats returned to non-stress environment, this difference of SYN expression (CA3 and DG regions) and working memory deficit between the two groups was still statistically significant. Our study findings suggested that early adverse experience enhances hippocampal vulnerability and working memory deficit in adult rats, and reduces structural plasticity of hippocampus.

  10. Spaced training facilitates long-term retention of place navigation in adult but not in adolescent rats.

    PubMed

    Spreng, Matthieu; Rossier, Jérôme; Schenk, Françoise

    2002-01-01

    Young and adult Long Evans rats were tested in the water maze according to two different procedures: half of the subjects were given one session of four trials a day for 6 days, whereas the other subjects had the same amount of training massed in 1 day. For both conditions, a 14-day retention interval was then introduced to test long-term memory. This was followed by a four-trial reversal session. All groups showed a significant learning curve, but escape latencies were shorter for the adult than for the young rats, without differential effect of the training procedure. A first probe trial (PT1) confirmed similar accurate short-term retention in all the groups. But unimpaired long-term memory was only seen in the adult rats trained with the spaced procedure. The young rats trained over 1 day also showed some retention of the platform location after 14 days, but not the other two groups. Reversal acquisition of the new platform location was rapid in the four groups. These results indicate that although accurate short-term spatial memory in the water maze is seen after a 1-day massed training in both age groups, unimpaired long-term retention is only observed in adult rats trained with 24-h inter-session intervals.

  11. Effect of MPEP in Morris water maze in adult and old rats.

    PubMed

    Car, Halina; Stefaniuk, Radosław; Wiśniewska, Róza J

    2007-01-01

    The present investigation assessed the effects of 2-methyl-6-(phenylethynyl)-pyridine (MPEP) on acquisition and reference memory in the Morris water maze in young adult rats aged 3-month and old rats aged 26-month. MPEP reduced the swim speed of the young adult rats during acquisition, shortened the distance they covered and reduced their swim speed in the probe trial. The untreated old rats had impaired acquisition of spatial learning, shortened distance and a lower swim speed in the probe trial in comparison with young rats. MPEP did not influence the activity of the old rats in the water maze. In summary, MPEP did not influence acquisition of spatial learning and reference memory in the young adult and old rats.

  12. Purification and culture of adult rat dorsal root ganglia neurons.

    PubMed

    Delree, P; Leprince, P; Schoenen, J; Moonen, G

    1989-06-01

    To study the trophic requirements of adult rat dorsal root ganglia neurons (DRG) in vitro, we developed a purification procedure that yields highly enriched neuronal cultures. Forty to fifty ganglia are dissected from the spinal column of an adult rat. After enzymatic and mechanical dissociation of the ganglia, myelin debris are eliminated by centrifugation on a Percoll gradient. The resulting cell suspension is layered onto a nylon mesh with a pore size of 10 microns. Most of the neurons, the diameter of which ranged from 17 microns to greater than 100 microns, are retained on the upper surface of the sieve; most of the non-neuronal cells with a caliber of less than 10 microns after trypsinization go through it. Recovery of neurons is achieved by reversing the mesh onto a Petri dish containing culture medium. Neurons to non-neurons ratio is 1 to 10 in the initial cell suspension and 1 to 1 after separation. When these purified neurons are seeded at a density of 3,000 neurons/cm2 in 6 mm polyornithine-laminin (PORN-LAM) coated wells, neuronal survival (assessed by the ability to extend neurites), measured after 48 hr of culture, is very low (from 0 to 16%). Addition of nerve growth factor (NGF) does not improve neuronal survival. However, when neurons are cultured in the presence of medium conditioned (CM) by astrocytes or Schwann cells, 60-80% of the seeded, dye-excluding neurons survive. So, purified adult DRG neurons require for their short-term survival and regeneration in culture, a trophic support that is present in conditioned medium from PNS or CNS glia.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Immature rat Leydig cells are intrinsically less sensitive than adult Leydig cells to ethane dimethanesulfonate.

    PubMed

    Kelce, W R; Zirkin, B R; Ewing, L L

    1991-11-01

    Leydig cells from immature rat testes appear to be insensitive to doses of ethane-1,2-dimethanesulfonate (EDS) which eliminate Leydig cells from adult rat testes. We sought to determine whether this differential response to EDS is intrinsic to the Leydig cell or mediated by other intra- or extratesticular differences between adult and immature rats. To differentiate among these possibilities, Leydig cells were exposed to EDS (1) in vivo, (2) through in vitro testicular perfusion, or (3) in highly purified Leydig cell primary cultures. Four days after ip injections of 85 mg EDS/kg body wt Leydig cells were eliminated from testes of adult, but not immature rats. Total androgen production by testes perfused in vitro with 94 micrograms EDS/ml was dramatically reduced in adult, but not immature rats. Highly purified adult, but not immature, rat Leydig cells were far more sensitive to the effects of EDS on luteinizing hormone-stimulated androgen production (functional effects; apparent EC50 = 94 for adult and 407 micrograms/ml for immature rat Leydig cells) and on [35S]methionine incorporation (cytotoxic effects; apparent EC50 = 140 for adult and 1000 micrograms/ml for immature rat Leydig cells). Finally, the in vitro effects of EDS were both cell type and chemical specific. Since the differential response of adult and immature rat Leydig cells to EDS was manifest in vivo, during in vitro testicular perfusion, and in highly purified Leydig cell primary cultures, we conclude that immature rat Leydig cells are intrinsically less sensitive to the specific cytotoxic effects of EDS than adult rat Leydig cells.

  14. Regulatory Mechanism of Muscle Disuse Atrophy in Adult Rats

    NASA Technical Reports Server (NTRS)

    1993-01-01

    During the last phase of NAG 2-386 we completed three studies. The effects of 14 days of weightlessness; the vastus medialis (VM) from flight rats in COSMOS 2044 was compared with the VM from tail suspended rats and other controls. The type I and II fibers in the mixed fiber portion of the VM were significantly reduced in flight rats and capillary densities paralleled the fiber density changes. The results of this project compared favorably with those in the extensor digitorum longus following seven days of flight in SL 3. The cardiovascular projects focused on the blood pressure changes in head down tilted rats (HDT) and non-head down tilted (N-HDT) rats. Blood pressures (MAP, SP and DP) were significantly elevated through seven days of HDT and rapidly returned to control levels within one day after removal from the HDT position. The N-HDT showed some slight rise in blood pressure but these were not as great and they were not as rapid. The HDT rats were characterized as exhibiting transient hypertension. These results led to some of the microvascular and vascular graduate student projects of Dr. Bernhard Stepke. Also our results refute or, at least, do not agree with previous reports from other laboratories. Each animal, in our blood pressure projects, served as its own control thereby providing more accurate results. Also, our experiments focused on recovery studies which can, in and of themselves, provide guidelines for flight experiments concerned with blood pressure changes. Another experiment was conducted to examine the role of testicular atrophy in whole body suspended (WBS) and tail suspended (TS) rats. We worked in conjunction with Dr. D.R. Deaver's laboratory at Pennsylvania State University and Dr. R. P. Amann at Colorado State University. In the TS rats the testes are retracted into the abdominal cavity, unless a ligature is placed to maintain them in the external scrotal sac. The cryptorchid condition in TS rats results in atrophy of the testes and

  15. 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.

  16. Myocardial infarction induces cognitive impairment by increasing the production of hydrogen peroxide in adult rat hippocampus.

    PubMed

    Liu, Chunhua; Liu, Ye; Yang, Zhuo

    2014-02-01

    Accumulating clinical evidence has shown a causal relationship between heart diseases and cognitive impairment in clinical, but the underlying mechanism remains unclear. In this study, rats with myocardial infarction (MI) were used to investigate cognition-related synaptic function and proteins. Adult male Wistar rats were subjected to MI by ligating of left anterior descending artery (LAD) and the infarct size of rat heart was measured by 2,3,5-triphenyltetrazoium chloride (TTC) staining. In this study, results showed that compared with control group, long-term potentiation was suppressed in dentate gyrus area, the contents of hydrogen peroxide (H2O2) and malondialdehyde were significantly increased, whereas the Cu/Zn-superoxide dismutase activity and N-methyl-d-aspartate receptor subunit 2B were attenuated in hippocampus of MI rats. Interestingly, it was observed that the PI3K/Akt pathway was activated in MI rats. Therefore, this study suggests that H2O2 plays an important role in cognitive dysfunction induced by MI.

  17. Early deprivation reduced anxiety and enhanced memory in adult male rats.

    PubMed

    Zhang, Xuliang; Wang, Bo; Jin, Jing; An, Shuming; Zeng, Qingwen; Duan, Yanhong; Yang, Liguo; Ma, Jing; Cao, Xiaohua

    2014-09-01

    The effects of early deprivation (ED, which involves both dam and littermate deprivation) on anxiety and memory are less investigated in comparison with maternal separation (MS), and it is not yet clear how ED affects long-term potentiation (LTP) in the hippocampal Schaffer collateral pathway. By using a series of behavioral tests, enzyme-linked immunosorbent assay and field potential recording, we explored the effect of pre-weaning daily 3-h ED on anxiety, memory and potential mechanisms in adult male rats. Compared with control, ED rats spent longer time in open arms of elevated plus maze and in light compartment of light-dark transition box. Consistently, stress-induced blood plasma corticosterone level was also lower in ED rats. Moreover, ED rats showed better performance in social recognition and Morris water maze test. In accordance with results in memory tests, the threshold of LTP induction in hippocampal CA3-CA1 pathway of ED rats was also reduced. Our results indicate ED reduced anxiety, but enhanced social recognition and spatial reference memory. We suggest the diminished hypothalamic-pituitary-adrenal axis response and facilitated hippocampal LTP may contribute to the anxiety-reducing and memory-enhancing effects of ED, respectively.

  18. Differential Effects of Acute Alcohol on Prepulse Inhibition and Event-Related Potentials in Adolescent and Adult Wistar Rats

    PubMed Central

    Pian, Jerry P.; Criado, Jose R.; Ehlers, Cindy L.

    2009-01-01

    Background Previous studies have demonstrated that adolescent and adult rats show differential sensitivity to many of the acute effects of alcohol. We recently reported evidence of developmental differences in the effects of acute alcohol on the cortical electroencephalogram (EEG). However, it is unclear whether developmental differences are also observed in other neurophysiological and neurobehavioral measurements known to be sensitive to alcohol exposure. The present study determined the age-related effects of acute alcohol on behavioral and event-related potential (ERP) responses to acoustic startle (AS) and prepulse inhibition (PPI). Methods Male adolescent and adult Wistar rats were implanted with cortical recording electrodes. The effects of acute alcohol (0.0, 0.75, and 1.5 g/kg) on behavioral and ERP responses to AS and PPI were assessed. Results Acute alcohol (0.75 and 1.5 g/kg) significantly reduced the behavioral and electrophysiological response to AS in adolescent and adult rats. Both 0.75 and 1.5 g/kg alcohol significantly enhanced the behavioral response to PPI in adolescent, but not in adult rats. During prepulse+pulse trials, 1.5 g/kg alcohol significantly increased the N10 pulse response in the adolescent frontal cortex. Acute alcohol (0.75 and 1.5 g/kg) also increased the N1 ERP pulse response to prepulse stimuli in frontal and parietal cortices in adult rats, but not in adolescent rats. Conclusions These data suggest that alcohol’s effect on behavioral and electrophysiological indices of AS do not differ between adults and adolescents whereas developmental stage does appear to significantly modify alcohol influenced response to PPI. PMID:18828807

  19. Analysis of proteome changes in doxorubicin-treated adult rat cardiomyocyte

    PubMed Central

    Kumar, Suresh N.; Konorev, Eugene A.; Aggarwal, Deepika; Kalyanaraman, Balaraman

    2011-01-01

    Doxorubicin-induced cardiomyopathy in cancer patients is well established. The proposed mechanism of cardiac damage includes generation of reactive oxygen species, mitochondrial dysfunction and cardiomyocyte apoptosis. Exposure of adult rat cardiomyocytes to low levels of DOX for 48 h induced apoptosis. Analysis of protein expression showed a differential regulation of several key proteins including the voltage dependent anion selective channel protein 2 and methylmalonate semialdehyde dehydrogenase. In comparison, proteomic evaluation of DOX-treated rat heart showed a slightly different set of protein changes that suggests nuclear accumulation of DOX. Using a new solubilization technique, changes in low abundant protein profiles were monitored. Altered protein expression, modification and function related to oxidative stress response may play an important role in DOX cardiotoxicity. PMID:21338723

  20. Effects of opioid (tramadol) treatment on testicular functions in adult male rats: The role of nitric oxide and oxidative stress.

    PubMed

    Ahmed, Marwa A; Kurkar, Adel

    2014-04-01

    Nowadays, tramadol hydrochloride is frequently used as a pain reliever, and for the treatment of premature ejaculation. Decreased semen quality was noted in chronic tramadol users. The present study aimed to elucidate the effects of tramadol on the testicular functions of adult male rats. A total of 40 albino adult male rats were divided into control and tramadol groups, with 20 rats for each group. Rats of the tramadol group were subcutaneously injected with 40 mg/kg three times per week for 8 weeks. The control group received normal saline 0.9%. Blood samples from each animal were obtained. Plasma levels of different biochemical substances were determined. Nitric oxide was measured in testicular tissue samples. Those samples together with epididymal tissue samples were processed for histopathological examination. Tramadol significantly reduced plasma levels of luteinizing hormone, follicle-stimulating hormone, testosterone and total cholesterol, but elevated prolactin and estradiol levels compared with the control group. In addition, tramadol increased the testicular levels of nitric oxide and lipid peroxidation, and decreased the anti-oxidant enzymes activities significantly compared with the control group. The tramadol group showed decreased sperm count and motility, and numbers of primary spermatocytes, rounded spermatid and Leydig cells. Immunohistochemical examinations showed that tramadol increased the expression of endothelial nitric oxide synthase in testicular tissues. The present study showed that tramadol treatment affects the testicular function of adult male rats, and these effects might be through the overproduction of nitric oxide and oxidative stress induced by this drug.

  1. Polygonal networks, "geodomes", of adult rat hepatocytes in primary culture.

    PubMed

    Mochizuki, Y; Furukawa, K; Mitaka, T; Yokoi, T; Kodama, T

    1988-01-01

    Polygonal networks, "geodomes", in cultured hepatocytes of adult rats were examined by both light and electron microscopy. On light microscopical examinations of specimens stained with Coomassie blue after the treatment with Triton X-100, the networks were detected 5 days after culture, which consisted of triangles arranged mainly in hexagonal patterns. They surrounded main cell body, looking like a headband, or were occasionally situated over nuclei, looking like a geodesic dome. Scanning electron microscopical observations after Triton treatment revealed that these structures were located underneath surface membrane. Transmission electron microscopical investigations revealed that the connecting fibers of networks consisted of microfilaments which radiated in a compact bundle from electron-dense vertices. PMID:3396075

  2. Cysteamine reduces serum gonadotropin concentrations in adult male rats.

    PubMed

    Badger, T M; Sagar, S M; Millard, W J; Martin, J B; Rosenblum, P

    1982-01-18

    We have examined the effects of cysteamine on the hypothalamic-pituitary-gonadal axis of the adult male rat. A single subcutaneous injection of cysteamine (300 mg/kg) reduces significantly (p less than or equal to 0.05 serum concentrations of LH, FSH and T. Cysteamine blocked LH secretion induced by castration and administration of naloxone and LHRH. Neither acute nor chronic treatment (7 days) altered the hypothalamic LHRH content. These results suggest that cysteamine acts to reduce pituitary responsiveness to LHRH, resulting in lower mean serum gonadotropin and testosterone concentrations. It is possible, however, that cysteamine acts also at the hypothalamus to reduce LHRH secretion and/or at the testes to reduce testosterone release.

  3. Resurgence of Response Sequences during Extinction in Rats Shows a Primacy Effect

    ERIC Educational Resources Information Center

    Reed, Phil; Morgan, Theresa A.

    2006-01-01

    Rats were trained to emit a series of three-response sequences to a criterion (i.e., more than 80% of all emitted sequences correct over five successive sessions). Each rat was trained on a series of different, three-response sequences. After the final three-response sequence was acquired, two extinction tests were administered, and the…

  4. Alterations in cytochrome P-450 levels in adult rats following neonatal exposure to xenobiotics

    SciTech Connect

    Zangar, R.C. Pacific Northwest Laboratories, Richland, WA ); Springer, D.L. ); Buhler, D.R. )

    1993-01-01

    Neonatal exposure to certain xenobiotics has been shown to alter hepatic metabolism in adult rats in a manner that indicates long-term changes in enzyme regulation. Previously, the authors have observed changes in adult testosterone metabolism and in cytochrome P-450 (P-450) mRNA levels in animals neonatally exposed to phenobarbital (PB) or diethylstilbestrol (DES). In order to test for other enzyme alterations, they used Western blot procedures for specific P-450s to analyze hepatic microsomes from adult rats (24 wk old) that had been exposed neonatally to DES, PB, 7,12-dimethylbenz[a]anthracene (DMBA), or pregnenolone 16[alpha]-carbonitrile (PCN). The most striking effects were observed in the DES-treated males: P-4502C6 and an immunologically similar protein were increased 60 and 90%, respectively, relative to control values, but P-4503A2 was decreased by 44%. No changes were observed in the DES-treated males in levels of P-4502E1, P-4502B, or the male-specific P-4502C13. Adult males neonatally treated with PB had 150% increase in levels of anti-P4502B-reactive protein without significant changes in the other enzymes. The DES- and DMBA-treated females had increased levels of the female-specific P-4502C12 of 38 and 48%, respectively, but no other observed alterations. The results confirm that neonatal exposure to DES or PB can cause alterations in adult hepatic cytochrome P-450 levels but show that these chemicals act on different enzymes. Neonatal DMBA resulted in changes in adult females similar to those produced by the synthetic estrogen DES, but did so at about two-thirds lower dose. 37 refs., 5 figs.

  5. Effect of Phaleria macrocarpa on Sperm Characteristics in Adult Rats

    PubMed Central

    Parhizkar, Saadat; Yusoff, Maryam Jamielah; Dollah, Mohammad Aziz

    2013-01-01

    Purpose: The purpose of this study was to determine the effects of Phaleria macrocarpa (PM) on male fertility by assessing its effect on the sperm characteristics which included the sperm count, motility, viability and morphology. Methods: Eighteen male rats were equally divided into three groups. Each group of rats was orally supplemented for 7 weeks either with PM aqueous extract (240 mg/kg), distilled water (0 mg/kg) or testosterone hormone, Andriol® Testocaps™ (4 mg/kg) respectively. On the last day of supplementation period, the rats were sacrificed and sperm was obtained from cauda epididymis via orchidectomy. The sperm count, motility, viability and morphology were determined. Results: PM aqueous extract significantly increased (p<0.05) the percentage of sperm viability. However, there was no significant effect of PM on the percentage of both sperm motility and morphology. The mean of body weight declined significantly in rats supplemented with PM aqueous extract compared to control groups (p<0.05). Conclusion: The results showed that PM significantly increased sperm viability without changing the sperm motility and morphology. Hence, this study suggests that PM offers an alternative way to improve male fertility by improving the sperm quality. PMID:24312859

  6. Prenatal exposure to dexamethasone alters Leydig cell steroidogenic capacity in immature and adult rats.

    PubMed

    Page, K C; Sottas, C M; Hardy, M P

    2001-01-01

    This study examines the effects of prenatal exposure to dexamethasone (DEX) on postnatal testosterone production in male rats. Pregnant female rats were treated on gestation days 14-19 with DEX (100 microg/kg body weight per day; n = 9) or vehicle (n = 9). Results show that 35-day-old male offspring from DEX-treated pregnant females (n = 42) had decreased levels of serum testosterone (45.6% lower, P < .05) compared with control offspring (n = 43), although serum luteinizing hormone (LH) levels were not significantly altered. These findings suggest that a direct programming of developing gonadal cells occurs in response to high levels of maternal glucocorticoid. Indeed, testosterone production was significantly reduced in Leydig cells isolated from immature offspring of DEX-treated pregnant females compared with controls (48.3%, P < .001), and LH stimulation of these cells did not compensate for the lowered steroidogenic capacity. The hypothalamic-pituitary-adrenal axis was also affected, because significant reductions in both serum adrenocorticotropic hormone (ACTH; 26.2%, P < .001) and corticosterone (CORT; 32.3%, P < .001) were measured in DEX-exposed immature male offspring. In contrast, adult male offspring from DEX-treated dams had significantly higher levels of serum ACTH (39.2%, P <. 001) and CORT (37.8%, P < .001). These same animals had higher serum testosterone (31.6%, P < or = .05) and a significant reduction in serum LH (30.8%, P < .001). Moreover, Leydig cells isolated from these adult offspring exhibited an increased capacity for testosterone biosynthesis under basal (38.6%, P < .001) and LH-stimulated conditions (33.5%, P < .001). In summary, sustained changes in steroidogenic capacity were observed in male rats exposed to high levels of glucocorticoid during prenatal development. More specifically, DEX exposure in utero perturbed Leydig cell testosterone production in both pubertal and adult rats.

  7. Mothers Do Not Show Increased Offspring Avoidance and Elevated Corticosterone Levels during Weaning Conflict in Rats

    PubMed Central

    Cox, Charlotte; Hager, Reinmar

    2016-01-01

    Parent-offspring conflict is predicted to occur because offspring will demand more parental investment than is optimal for the parent, and is said to be strongest during weaning when parents reduce nursing while offspring continue to demand parental care. While weaning conflict has been shown to be stressful in offspring, little is known about the effects of weaning conflict on mothers. We hypothesized that during weaning mothers have higher levels of stress hormone (corticosterone) compared to early lactation because of increased offspring demand. Further, we predicted that if mothers are given the option to avoid offspring solicitation they would do so and show lower corticosterone levels. We tested our hypotheses in an experimental population of rats in which one group of females was given the opportunity to avoid offspring solicitation. We measured faecal corticosterone metabolite levels using a non-invasive approach, and maternal and offspring behaviours during weaning. In contrast to our predictions, we detected lower levels of corticosterone metabolites during weaning than before, irrespective of cage type. Further, during weaning mothers did not show increased offspring avoidance behaviour although offspring solicitation increased significantly. Our results therefore cast doubt on the generally accepted notion of weaning conflict as a stressful period for mothers characterized by overt offspring solicitation. PMID:27662366

  8. Astaxanthin reduces ischemic brain injury in adult rats.

    PubMed

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N; Post, Jeremy; Woods, Amina S; Hoffer, Barry J; Wang, Yun; Harvey, Brandon K

    2009-06-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events. PMID:19218497

  9. Astaxanthin reduces ischemic brain injury in adult rats.

    PubMed

    Shen, Hui; Kuo, Chi-Chung; Chou, Jenny; Delvolve, Alice; Jackson, Shelley N; Post, Jeremy; Woods, Amina S; Hoffer, Barry J; Wang, Yun; Harvey, Brandon K

    2009-06-01

    Astaxanthin (ATX) is a dietary carotenoid of crustaceans and fish that contributes to their coloration. Dietary ATX is important for development and survival of salmonids and crustaceans and has been shown to reduce cardiac ischemic injury in rodents. The purpose of this study was to examine whether ATX can protect against ischemic injury in the mammalian brain. Adult rats were injected intracerebroventricularly with ATX or vehicle prior to a 60-min middle cerebral artery occlusion (MCAo). ATX was present in the infarction area at 70-75 min after onset of MCAo. Treatment with ATX, compared to vehicle, increased locomotor activity in stroke rats and reduced cerebral infarction at 2 d after MCAo. To evaluate the protective mechanisms of ATX against stroke, brain tissues were assayed for free radical damage, apoptosis, and excitoxicity. ATX antagonized ischemia-mediated loss of aconitase activity and reduced glutamate release, lipid peroxidation, translocation of cytochrome c, and TUNEL labeling in the ischemic cortex. ATX did not alter physiological parameters, such as body temperature, brain temperature, cerebral blood flow, blood gases, blood pressure, and pH. Collectively, our data suggest that ATX can reduce ischemia-related injury in brain tissue through the inhibition of oxidative stress, reduction of glutamate release, and antiapoptosis. ATX may be clinically useful for patients vulnerable or prone to ischemic events.

  10. Comparison of electroretinographic responses between two different age groups of adult Dark Agouti rats

    PubMed Central

    Fu, Lin; Lo, Amy Cheuk Yin; Lai, Jimmy Shiu Ming; Shih, Kendrick Co

    2015-01-01

    AIM To describe and compare the differences in electroretinographic responses between two different age groups of adult Dark Agouti (DA) rats and to better understand the effect of age on retinal histology and function. METHODS The electroretinographic responses of two different age groups of adult DA rats were compared. Animals were divided into younger adult DA rats 10-12wk (n=8) and older adult DA rats 17-19wk (n=8). Full field electroretinography (ERG) was recorded simultaneously from both eyes after dark adaption and light adaption and parameters including the positive scotopic threshold response (pSTR), negative scotopic threshold response (nSTR), scotopic a-wave, b-wave, photopic a-wave, b-wave and photopic negative response (PhNR) were compared between groups. RESULTS The older adult rats displayed lower stimulation thresholds of the STRs (pSTR and nSTR) and higher amplitudes of pSTR, scotopic a-wave and b-wave, photopic b-wave and PhNR amplitudes, with shorter implicit times. Photopic a-wave amplitudes were however higher in the younger adult rats. CONCLUSION In summary, for the rod system, photoreceptor, bipolar cell and RGC activity was enhanced in the older adult rats. For the cone system, RGC and bipolar cell activity was enhanced, while photoreceptor activity was depressed in the older adult rats. Such age-related selective modification of retinal cell function needs to be considered when conducting ophthalmic research in adult rats. PMID:26558198

  11. Impaired contextual fear extinction and hippocampal synaptic plasticity in adult rats induced by prenatal morphine exposure.

    PubMed

    Tan, Ji-Wei; Duan, Ting-Ting; Zhou, Qi-Xin; Ding, Ze-Yang; Jing, Liang; Cao, Jun; Wang, Li-Ping; Mao, Rong-Rong; Xu, Lin

    2015-07-01

    Prenatal opiate exposure causes a series of neurobehavioral disturbances by affecting brain development. However, the question of whether prenatal opiate exposure increases vulnerability to memory-related neuropsychiatric disorders in adult offspring remains largely unknown. Here, we found that rats prenatally exposed to morphine (PM) showed impaired acquisition but enhanced maintenance of contextual fear memory compared with control animals that were prenatally exposed to saline (PS). The impairment of acquisition was rescued by increasing the intensity of footshocks (1.2 mA rather than 0.8 mA). Meanwhile, we also found that PM rats exhibited impaired extinction of contextual fear, which is associated with enhanced maintenance of fear memory. The impaired extinction lasted for 1 week following extinction training. Furthermore, PM rats exhibited reduced anxiety-like behavior in the elevated plus-maze and light/dark box test without differences in locomotor activity. These alterations in PM rats were mirrored by abnormalities in synaptic plasticity in the Schaffer collateral-CA1 synapses of the hippocampus in vivo. PS rats showed blocked long-term potentiation and enabled long-term depression in CA1 synapses following contextual fear conditioning, while prenatal morphine exposure restricted synaptic plasticity in CA1 synapses. The smaller long-term potentiation in PM rats was not further blocked by contextual fear conditioning, and the long-term depression enabled by contextual fear conditioning was abolished. Taken together, our results provide the first evidence suggesting that prenatal morphine exposure may increase vulnerability to fear memory-related neuropsychiatric disorders in adulthood.

  12. Older adults show a self-reference effect for narrative information.

    PubMed

    Carson, Nicole; Murphy, Kelly J; Moscovitch, Morris; Rosenbaum, R Shayna

    2016-10-01

    The self-reference effect (SRE), enhanced memory for information encoded through self-related processing, has been established in younger and older adults using single trait adjective words. We sought to examine the generality of this phenomenon by studying narrative information in these populations. Additionally, we investigated retrieval experience at recognition and whether valence of stimuli influences memory differently in young and older adults. Participants encoded trait adjectives and narratives in self-reference, semantic, or structural processing conditions, followed by tests of recall and recognition. Experiment 1 revealed an SRE for trait adjective recognition and narrative cued recall in both age groups, although the existence of an SRE for narrative recognition was unclear due to ceiling effects. Experiment 2 revealed an SRE on an adapted test of narrative recognition. Self-referential encoding was shown to enhance recollection for both trait adjectives and narrative material in Experiment 1, whereas similar estimates of recollection for self-reference and semantic conditions were found in Experiment 2. Valence effects were inconsistent but generally similar in young and older adults when they were found. Results demonstrate that the self-reference technique extends to narrative information in young and older adults and may provide a valuable intervention tool for those experiencing age-related memory decline.

  13. Older adults show a self-reference effect for narrative information.

    PubMed

    Carson, Nicole; Murphy, Kelly J; Moscovitch, Morris; Rosenbaum, R Shayna

    2016-10-01

    The self-reference effect (SRE), enhanced memory for information encoded through self-related processing, has been established in younger and older adults using single trait adjective words. We sought to examine the generality of this phenomenon by studying narrative information in these populations. Additionally, we investigated retrieval experience at recognition and whether valence of stimuli influences memory differently in young and older adults. Participants encoded trait adjectives and narratives in self-reference, semantic, or structural processing conditions, followed by tests of recall and recognition. Experiment 1 revealed an SRE for trait adjective recognition and narrative cued recall in both age groups, although the existence of an SRE for narrative recognition was unclear due to ceiling effects. Experiment 2 revealed an SRE on an adapted test of narrative recognition. Self-referential encoding was shown to enhance recollection for both trait adjectives and narrative material in Experiment 1, whereas similar estimates of recollection for self-reference and semantic conditions were found in Experiment 2. Valence effects were inconsistent but generally similar in young and older adults when they were found. Results demonstrate that the self-reference technique extends to narrative information in young and older adults and may provide a valuable intervention tool for those experiencing age-related memory decline. PMID:26360612

  14. Do Adults with Mental Retardation Show Pictorial Superiority Effects in Recall and Recognition?

    ERIC Educational Resources Information Center

    Cherry, Katie E.; Applegate, Heather; Reese, Celinda M.

    2002-01-01

    A study examined memory for pictures and words in 16 adults with mental retardation and 24 controls. Pictorial superiority effects occurred in free recall and recognition for both intelligence-level groups. Correlational analyses indicated working memory span was primarily related to recall performance, irrespective of stimulus format. (Contains…

  15. Do Adults Show an Effect of Delayed First Language Acquisition When Calculating Scalar Implicatures?

    PubMed Central

    Davidson, Kathryn; Mayberry, Rachel I

    2015-01-01

    Language acquisition involves learning not only grammatical rules and a lexicon, but also what someone is intending to convey with their utterance: the semantic/pragmatic component of language. In this paper we separate the contributions of linguistic development and cognitive maturity to the acquisition of the semantic/pragmatic component of language by comparing deaf adults who had either early or late first exposure to their first language (ASL). We focus on the particular type of meaning at the semantic/pragmatic interface called scalar implicature, for which preschool-age children typically differ from adults. Children's behavior has been attributed to either their not knowing appropriate linguistic alternatives to consider or to cognitive developmental differences between children and adults. Unlike children, deaf adults with late language exposure are cognitively mature, although they never fully acquire some complex linguistic structures, and thus serve as a test for the role of language in such interpretations. Our results indicate an overall high performance by late learners, especially when implicatures are not based on conventionalized items. However, compared to early language learners, late language learners compute fewer implicatures when conventionalized linguistic alternatives are involved (e.g. ). We conclude that (i) in general, Gricean pragmatic reasoning does not seem to be impacted by delayed first language acquisition and can account for multiple quantity implicatures, but (ii) the creation of a scale based on lexical items can lead to ease in alternative creation that may be advantageously learned early in life, and that this may be one of several factors contributing to differences between adults and children on scalar implicature tasks. PMID:26997850

  16. Neonatal injections of methoxychlor decrease adult rat female reproductive behavior.

    PubMed

    Bertolasio, Jennifer; Fyfe, Susanne; Snyder, Ben W; Davis, Aline M

    2011-12-01

    Methoxychlor (MXC), a commonly used pesticide, has been labeled as an endocrine disruptor. To evaluate the impact of neonatal exposure to MXC on female reproduction, female Sprague-Dawley rats were given subcutaneous injections on postnatal days 1, 3, and 5. The injections contained 1.0mg MXC, 2.0mg MXC, 10 μg 17β-estradiol benzoate (positive control), or sesame oil (vehicle). The injections of MXC had no effect on anogenital distance or day of vaginal opening. Treatment with either 2.0mg MXC or estradiol significantly increased the total number of days with vaginal keratinization. Treatment with MXC had no effect on ability to exhibit a mating response as an adult female, although the high dose MXC (2.0) and the positive control (estradiol) animals demonstrated a decrease in degree of receptivity, a decrease in proceptive behavior and an increase in rejection behavior. These data suggest that higher doses of MXC given directly to pups during the neonatal period can act as an estrogen and alter aspects of the nervous system, impacting adult reproductive characteristics.

  17. Unilateral eye enucleation in adult rats causes neuronal loss in the contralateral superior colliculus

    PubMed Central

    SMITH, S. A.; BEDI, K. S.

    1997-01-01

    Several studies have reported the morphological changes induced by unilateral enucleation during early neonatal life on the developing visual system. This study has examined cellular changes in the superior colliculi by removal of a single eye in adult rats. Anaesthetised male hooded rats aged 90 d had their right eyes removed. Groups of nonenucleated control and enucleated rats were killed when aged either 150 or 390 d. The brains were removed and both the right and left superior colliculi dissected out. The volume of the stratum griseum superficiale (SGS) within these colliculi was estimated stereologically by light microscopy, as well as the numerical density and total number of neurons within this cell layer. The volume of the cell layer was reduced by about 40% on the side contralateral to the enucleated eye but not on the ipsilateral side at both survival periods examined. The numerical density of neurons within the SGS was unaffected by the enucleation so that the colliculi contralateral to the enucleated eye showed a substantial loss of neurons within this cell layer. This study demonstrates the importance of the retinal ganglion cell input, even in adult animals, for maintaining the viability of neurons in the SGS layer of the superior colliculus. PMID:9183672

  18. Evidence of lactoferrin transportation into blood circulation from intestine via lymphatic pathway in adult rats.

    PubMed

    Takeuchi, Takashi; Kitagawa, Hiroshi; Harada, Etsumori

    2004-05-01

    Using adult rats, the characteristic transporting system for lactoferrin (LF) from intestinal lumen into the blood circulation was investigated. The rats were randomly divided into two groups, a non-collected thoracic lymph (NC) group and a collected thoracic lymph (LC) group. Peripheral blood and thoracic lymph were collected from a jugular vein and a thoracic lymph duct, respectively, under anaesthesia. Bovine LF (bLF) was infused into the duodenal lumen by needle over a 1-min period at a dose of 1 g kg(-1). The transported bLF in the plasma and lymph was assayed quantitatively by double-antibody enzyme-linked immunosorbent assay (ELISA). Morphological investigation was also carried out in the intestine, lymph node, and liver. Following intraduodenal administration of bLF, the transported bLF in the NC group was detected in the plasma, and reached a peak value at 2 h. Furthermore, the bLF concentration in the thoracic duct lymph fluid in the LC group increased significantly, and peaked 2 h after the administration. In addition, bLF was not detected in the plasma of the LC group. Immunohistochemical analysis clearly showed anti-bLF positive particles in the epithelial cells of the apical villi. The striated border and baso-lateral membrane were also bLF positive. These results suggest that intraduodenally infused bLF is transported into the blood circulation via the lymphatic pathway, not via portal circulation in adult rats.

  19. Influence of hyperoxia and mechanical ventilation in lung inflammation and diaphragm function in aged versus adult rats.

    PubMed

    Andrade, P V; dos Santos, J M; Silva, H C A; Wilbert, D D; Cavassani, S S; Oliveira-Júnior, I S

    2014-04-01

    Although assist ventilation with FIO2 0.21 is the preferable mode of ventilation in the intensive care unit, sometimes controlled ventilation with hyperoxia is needed. But the impact of this setting has not been extensively studied in elderly subjects. We hypothesized that a high fraction of inspired oxygen (FiO(2)) and controlled mechanical ventilation (CMV) is associated with greater deleterious effects in old compared to adult subjects. Adult and old rats were submitted to CMV with low tidal volume (6 ml/kg) and FiO(2) 1 during 3 or 6 h. Arterial blood gas samples were measured at 0, 60 and 180 min (four groups: old and adult rats, 3 or 6 h of CMV), and additionally at 360 min (two groups: old and adult rats, 6 h of CMV). Furthermore, total protein content (TPC) and tumor necrosis factor-alpha (TNF-α) in bronchoalveolar lavage were assessed; lung tissue was used for malondialdehyde and histological analyses, and the diaphragm for measurement of contractile function. Arterial blood gas analysis showed an initial (60 min) greater PaO(2) in elderly versus adult animals; after that time, elderly animals had lowers pH and PaO(2), and greater PaCO(2). After 3 h of CMV, TPC and TNF-α levels were higher in the old compared with the adult group (P < 0.05). After 6 h of MV, malondialdehyde was significantly higher in elderly compared with the adult animals (P < 0.05). Histological analysis showed leukocyte infiltration and edema, greater in old animals. In diaphragm, twitch contraction with caffeine significantly declined after 6 h of CMV only for the elderly group. These data support the hypothesis that relatively short-term CMV with low tidal volume and hyperoxia has greatest impact in elderly rats, decreasing diaphragmatic contractile function and increasing lung inflammation.

  20. Effect of MDMA (ecstasy) on activity and cocaine conditioned place preference in adult and adolescent rats.

    PubMed

    Aberg, Maria; Wade, Dean; Wall, Erin; Izenwasser, Sari

    2007-01-01

    MDMA (ecstasy) is a drug commonly used in adolescence, and many users of MDMA also use other illicit drugs. It is not known whether MDMA during adolescence alters subsequent responses to cocaine differently than in adults. This study examined the effects of MDMA in adolescent and adult rats on cocaine conditioned reward. At the start of these experiments, adolescent rats were at postnatal day (PND) 33 and adult rats at PND 60. Each rat was treated for 7 days with MDMA (2 or 5 mg/kg/day or vehicle) and locomotor activity was measured. Five days later cocaine conditioned place preference (CPP) was begun. Rats were trained for 3 days, in the morning with saline and in the afternoon with 10 mg/kg cocaine in 30 min sessions, and tested on the fourth day. MDMA stimulated activity in both age groups, but with a greater effect in the adult rats. Sensitization to the locomotor-stimulant effects of the lower dose of MDMA occurred in adult rats and in both groups to the higher dose. Cocaine did not produce a CPP in vehicle-treated adolescent rats, but a significant CPP was observed subsequent to treatment with MDMA. In contrast, cocaine-induced CPP was diminished after MDMA in adult rats. These effects were still evident 2 weeks later upon retest. Thus, under the present conditions, MDMA increased cocaine conditioned reward in adolescent and decreased it in adult rats. These findings suggest that exposure to MDMA during this critical developmental period may carry a greater risk than during adulthood and that male adolescents may be particularly vulnerable to the risk of stimulant abuse after use of MDMA.

  1. Influx mechanisms in the embryonic and adult rat choroid plexus: a transcriptome study

    PubMed Central

    Saunders, Norman R.; Dziegielewska, Katarzyna M.; Møllgård, Kjeld; Habgood, Mark D.; Wakefield, Matthew J.; Lindsay, Helen; Stratzielle, Nathalie; Ghersi-Egea, Jean-Francois; Liddelow, Shane A.

    2015-01-01

    The transcriptome of embryonic and adult rat lateral ventricular choroid plexus, using a combination of RNA-Sequencing and microarray data, was analyzed by functional groups of influx transporters, particularly solute carrier (SLC) transporters. RNA-Seq was performed at embryonic day (E) 15 and adult with additional data obtained at intermediate ages from microarray analysis. The largest represented functional group in the embryo was amino acid transporters (twelve) with expression levels 2–98 times greater than in the adult. In contrast, in the adult only six amino acid transporters were up-regulated compared to the embryo and at more modest enrichment levels (<5-fold enrichment above E15). In E15 plexus five glucose transporters, in particular Glut-1, and only one monocarboxylate transporter were enriched compared to the adult, whereas only two glucose transporters but six monocarboxylate transporters in the adult plexus were expressed at higher levels than in embryos. These results are compared with earlier published physiological studies of amino acid and monocarboxylate transport in developing rodents. This comparison shows correlation of high expression of some transporters in the developing brain with higher amino acid transport activity reported previously. Data for divalent metal transporters are also considered. Immunohistochemistry of several transporters (e.g., Slc16a10, a thyroid hormone transporter) gene products was carried out to confirm translational activity and to define cellular distribution of the proteins. Overall the results show that there is substantial expression of numerous influx transporters in the embryonic choroid plexus, many at higher levels than in the adult. This, together with immunohistochemical evidence and data from published physiological transport studies suggests that the choroid plexus in embryonic brain plays a major role in supplying the developing brain with essential nutrients. PMID:25972776

  2. Homeostatic regulation of adult hippocampal neurogenesis in aging rats: long-term effects of early exercise

    PubMed Central

    Merkley, Christina M.; Jian, Charles; Mosa, Adam; Tan, Yao-Fang; Wojtowicz, J. Martin

    2014-01-01

    Adult neurogenesis is highly responsive to environmental and physiological factors. The majority of studies to date have examined short-term consequences of enhancing or blocking neurogenesis but long-term changes remain less well understood. Current evidence for age-related declines in neurogenesis warrant further investigation into these long-term changes. In this report we address the hypothesis that early life experience, such as a period of voluntary running in juvenile rats, can alter properties of adult neurogenesis for the remainder of the animal's life. The results indicate that the number of proliferating and differentiating neuronal precursors is not altered in runners beyond the initial weeks post-running, suggesting homeostatic regulation of these processes. However, the rate of neuronal maturation and survival during a 4 week period after cell division was enhanced up to 11 months of age (the end of the study period). This study is the first to show that a transient period of physical activity at a young age promotes changes in neurogenesis that persist over the long-term, which is important for our understanding of the modulation of neurogenesis by exercise with age. Functional integration of adult-born neurons within the hippocampus that resist homeostatic regulation with aging, rather than the absolute number of adult-born neurons, may be an essential feature of adult neurogenesis that promotes the maintenance of neural plasticity in old age. PMID:25071426

  3. Ghrelin modulates testicular germ cells apoptosis and proliferation in adult normal rats

    SciTech Connect

    Kheradmand, Arash; Dezfoulian, Omid; Alirezaei, Masoud; Rasoulian, Bahram

    2012-03-09

    , ghrelin balanced Bax/Bcl-2 ratio toward at increase of Bax level in the spermatocytes and therefore may stimulate apoptosis in these germ cells. In contrast, ghrelin administration significantly suppressed proliferation-associated peptide PCNA in the spermatocytes as well as spermatogonia (P < 0.05). Whereas, caspase-3 activity did not show any marked alteration during the experiment in both groups (P > 0.05). Upstream of Bax substance parallel to down-regulation of PCNA demonstrate that ghrelin may prevent massive accumulation of germ cells during normal spermatogenesis. These observations also indicate that ghrelin may be considered as a modulator of spermatogenesis in normal adult rats and could be potentially implicated for abnormal spermatogenesis in some testicular germ cell tumors.

  4. Nuclear transfer of adult and genetically modified fetal cells of the rat.

    PubMed

    Hayes, E; Galea, S; Verkuylen, A; Pera, M; Morrison, J; Lacham-Kaplan, O; Trounson, A

    2001-04-27

    The present study examines the handling, activation, and micromanipulation of rat eggs in an attempt to produce live young using nuclear transfer (NT) of adult and genetically modified rat fetal cells. Mature rat eggs cultured in calcium-free medium showed reduced rates (24%) of chromosomal dispersion ("spontaneous activation" characteristic of this species) compared with eggs cultured in calcium-containing medium (47%), but failed to survive micromanipulation procedures. High rates of parthenogenetic cleavage were obtained with chemical activation using ethanol/cycloheximide (65%) compared with other standard chemical activation methods (4-28%). This type of activation was also effective in reestablishing cleavage capability (19-71%), in a time-dependent manner, of spontaneously activated eggs arrested at a second prophase-like state. At most, two of four tested micromanipulation procedures were effective in producing NT embryos capable of morula or blastocyst development (14-16%) in vivo following transfer to mouse oviducts. NT blastocysts produced from cumulus cells and transfected rat fetal fibroblasts appeared morphologically and karyotypically normal (2n = 42). Nocodazole-assisted metaphase enucleation and piezoelectric-assisted donor cell injection produced significant and equivocal effects on survival and cleavage rates of reconstructed embryos but failed to significantly improve in vivo morula/blastocyst development rates (16-28%) compared with unassisted micromanipulation (16%). Live births have not yet been obtained from early cleavage stage embryos (n = 269) transferred to pseudopregnant recipient rat oviducts. Improvements in reconstituted NT embryo culture and transfer are required for these methods to be an effective means of transgenic rat production.

  5. Abnormal secretion of reproductive hormones and antioxidant status involved in quinestrol-induced reproductive toxicity in adult male rat.

    PubMed

    Li, Jian; Wang, Hongwei; Zhang, Jiliang; Zhou, Bianhua; Si, Lifang; Wei, Lan; Li, Xiang

    2014-02-01

    This study aimed to evaluate the effects of quinestrol, a synthetic oestrogen homologue with reproductive toxicity, on the secretion of reproductive hormones and antioxidant status in adult male rat. Our results showed that quinestrol exposure significantly decreased the weight of the testis, epididymides, seminal vesicle, and prostate, as well as the sperm counts in the cauda epididymis of rats. Quinestrol significantly reduced the size of seminiferous tubules and the total number of spermatogenic cells. Serum testosterone, follitropin, and lutropin were also significantly reduced in a dose-related manner after quinestrol exposure. Meanwhile, the activity of superoxide dismutase, glutathione peroxidase, and total antioxide capacity significantly decreased, whereas the malondialdehyde and nitric oxide concentrations significantly increased in the testes. These findings revealed that endocrine disorders of reproductive hormones and oxidative stress may be involved in reproductive toxicity induced by quinestrol in adult male rats. PMID:24183492

  6. Prenatal caffeine exposure induces a poor quality of articular cartilage in male adult offspring rats via cholesterol accumulation in cartilage.

    PubMed

    Luo, Hanwen; Li, Jing; Cao, Hong; Tan, Yang; Magdalou, Jacques; Chen, Liaobin; Wang, Hui

    2015-12-07

    Epidemiological investigations indicate that osteoarthritis is associated with intrauterine growth retardation (IUGR) and abnormal cholesterol metabolism. Our previous studies showed that prenatal caffeine exposure (PCE) induced chondrogenesis retardation in IUGR offspring rats. The current study sought to investigate the effects of PCE on male IUGR offspring rats' articular cartilage, and the mechanisms associated with abnormal cholesterol metabolism. Based on the results from both male fetal and adult fed a high-fat diet (HFD) studies of rats that experienced PCE (120 mg/kg.d), the results showed a poor quality of articular cartilage and cholesterol accumulation in the adult PCE group. Meanwhile, the serum total cholesterol and low-density lipoprotein-cholesterol concentrations were increased in adult PCE offspring. We also observed lower expression of insulin-like growth factor1 (IGF1) and impaired cholesterol efflux in adult articular cartilage. Furthermore, the expression of cartilage functional genes, components of the IGF1 signaling pathway and cholesterol efflux pathway related genes were decreased in PCE fetal cartilage. In conclusion, PCE induced a poor quality of articular cartilage in male adult offspring fed a HFD. This finding was shown to be due to cholesterol accumulation in the cartilage, which may have resulted from intrauterine reduced activity of the IGF1 signaling pathway.

  7. Sodium metabisulfite-induced changes on testes, spermatogenesis and epididymal morphometric values in adult rats

    PubMed Central

    Shekarforoush, Shahnaz; Ebrahimi, Zahra; Hoseini, Maryam

    2015-01-01

    Background: Sulphites are widely used as a preservative and antioxidant additives in the food and pharmaceutical industries. Many types of biological and toxicological effects of sulphites in multiple organs of mammals have been shown in previous studies. Objective: The aim of this study was to investigate the effects of sodium metabisulfite (SMB) on testicular function and morphometric values of epididymis in adult male Wistar rats. Materials and Methods: A total of 32 rats were randomly divided into four groups. The experimental groups received SMB at doses of 10 mg/kg (S10), 100mg/kg (S100), and 260 mg/kg (S260) while an equal volume of normal saline was administered to the control group via gavage. The rats were anaesthetized after 28 days and the left testis with the head of epididimis was excised following abdominal incision for histological observation using hematoxylin and eosin staining. Serum samples were collected for assay of testosterone level. The initial epididymis was analyzed for motility, morphology, and the number of sperms. Result: The results of this study showed that normal morphology, count, and motility of sperms and testosterone level were decreased in the SMB treated groups. In comparison with the control group, SMB resulted in a lower total number of spermatogonia, primary spermatocyte, spermatids, and Leydig cells. Conclusion: It is suggested that SMB decreases the sperm production and has the potential to affect the fertility adversely in male rats. PMID:27141536

  8. A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats.

    PubMed

    Lin, Tiao; Tong, Wei; Chandra, Abhishek; Hsu, Shao-Yun; Jia, Haoruo; Zhu, Ji; Tseng, Wei-Ju; Levine, Michael A; Zhang, Yejia; Yan, Shi-Gui; Liu, X Sherry; Sun, Dongming; Young, Wise; Qin, Ling

    2015-01-01

    Spinal cord injury (SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment. Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae, and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography (µCT), micro-finite element, histology, and serum biochemical analyses. At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI. PMID:26528401

  9. Tianeptine facilitates spreading depression in well-nourished and early-malnourished adult rats.

    PubMed

    Amancio-Dos-Santos, Angela; Maia, Luciana Maria Silva de Seixas; Germano, Paula Catirina Pereira da Silva; Negrão, Yleana Danielle Dos Santos; Guedes, Rubem Carlos Araújo

    2013-04-15

    Nutritional status during development can modify the brain's electrophysiological properties and its response to drugs that reduce the serotonin availability in the synaptic cleft. Here we used cortical spreading depression (CSD) in the rat as a neurophysiological parameter to investigate the interaction between nutritional status and treatment with tianeptine, a serotonin uptake enhancer. From postnatal day 2 to 24, well-nourished and early-malnourished rat pups were s.c. injected with tianeptine (5 or 10mg/kg; 10 ml/kg) or equivalent volume of saline solution (control group). When the animals were 25-30 days old, CSD was recorded on the brain cortical surface. In the well-nourished rats, but not in the malnourished group, systemic tianeptine dose-dependently increased the CSD propagation velocity, with 10mg/kg producing a significant (P<0.05) effect. An experiment in adult rats showed that cortical topical application of tianeptine solutions (5mg/ml, 10mg/ml, and 20mg/ml) increased the CSD propagation in both the well-nourished and early-malnourished conditions. In well-nourished animals, 0.5mg/ml topical tianeptine did not affect CSD propagation, and 2mg/ml produced a small, but significant CSD acceleration. Our results indicate a facilitating action of tianeptine on CSD propagation, probably via tianeptine's pharmacological action on the serotonin system. These findings support previous data suggesting an antagonistic role of the serotoninergic system on CSD.

  10. A comprehensive study of long-term skeletal changes after spinal cord injury in adult rats

    PubMed Central

    Lin, Tiao; Tong, Wei; Chandra, Abhishek; Hsu, Shao-Yun; Jia, Haoruo; Zhu, Ji; Tseng, Wei-Ju; Levine, Michael A; Zhang, Yejia; Yan, Shi-Gui; Liu, X Sherry; Sun, Dongming; Young, Wise; Qin, Ling

    2015-01-01

    Spinal cord injury (SCI)-induced bone loss represents the most severe osteoporosis with no effective treatment. Past animal studies have focused primarily on long bones at the acute stage using adolescent rodents. To mimic chronic SCI in human patients, we performed a comprehensive analysis of long-term structural and mechanical changes in axial and appendicular bones in adult rats after SCI. In this experiment, 4-month-old Fischer 344 male rats received a clinically relevant T13 contusion injury. Sixteen weeks later, sublesional femurs, tibiae, and L4 vertebrae, supralesional humeri, and blood were collected from these rats and additional non-surgery rats for micro-computed tomography (µCT), micro-finite element, histology, and serum biochemical analyses. At trabecular sites, extreme losses of bone structure and mechanical competence were detected in the metaphysis of sublesional long bones after SCI, while the subchondral part of the same bones showed much milder damage. Marked reductions in bone mass and strength were also observed in sublesional L4 vertebrae but not in supralesional humeri. At cortical sites, SCI induced structural and strength damage in both sub- and supralesional long bones. These changes were accompanied by diminished osteoblast number and activity and increased osteoclast number and activity. Taken together, our study revealed site-specific effects of SCI on bone and demonstrated sustained inhibition of bone formation and elevation of bone resorption at the chronic stage of SCI. PMID:26528401

  11. Tianeptine facilitates spreading depression in well-nourished and early-malnourished adult rats.

    PubMed

    Amancio-Dos-Santos, Angela; Maia, Luciana Maria Silva de Seixas; Germano, Paula Catirina Pereira da Silva; Negrão, Yleana Danielle Dos Santos; Guedes, Rubem Carlos Araújo

    2013-04-15

    Nutritional status during development can modify the brain's electrophysiological properties and its response to drugs that reduce the serotonin availability in the synaptic cleft. Here we used cortical spreading depression (CSD) in the rat as a neurophysiological parameter to investigate the interaction between nutritional status and treatment with tianeptine, a serotonin uptake enhancer. From postnatal day 2 to 24, well-nourished and early-malnourished rat pups were s.c. injected with tianeptine (5 or 10mg/kg; 10 ml/kg) or equivalent volume of saline solution (control group). When the animals were 25-30 days old, CSD was recorded on the brain cortical surface. In the well-nourished rats, but not in the malnourished group, systemic tianeptine dose-dependently increased the CSD propagation velocity, with 10mg/kg producing a significant (P<0.05) effect. An experiment in adult rats showed that cortical topical application of tianeptine solutions (5mg/ml, 10mg/ml, and 20mg/ml) increased the CSD propagation in both the well-nourished and early-malnourished conditions. In well-nourished animals, 0.5mg/ml topical tianeptine did not affect CSD propagation, and 2mg/ml produced a small, but significant CSD acceleration. Our results indicate a facilitating action of tianeptine on CSD propagation, probably via tianeptine's pharmacological action on the serotonin system. These findings support previous data suggesting an antagonistic role of the serotoninergic system on CSD. PMID:23499681

  12. Auditory map reorganization and pitch discrimination in adult rats chronically exposed to low-level ambient noise

    PubMed Central

    Zheng, Weimin

    2012-01-01

    Behavioral adaption to a changing environment is critical for an animal's survival. How well the brain can modify its functional properties based on experience essentially defines the limits of behavioral adaptation. In adult animals the extent to which experience shapes brain function has not been fully explored. Moreover, the perceptual consequences of experience-induced changes in the brains of adults remain unknown. Here we show that the tonotopic map in the primary auditory cortex of adult rats living with low-level ambient noise underwent a dramatic reorganization. Behaviorally, chronic noise-exposure impaired fine, but not coarse pitch discrimination. When tested in a noisy environment, the noise-exposed rats performed as well as in a quiet environment whereas the control rats performed poorly. This suggests that noise-exposed animals had adapted to living in a noisy environment. Behavioral pattern analyses revealed that stress or distraction engendered by the noisy background could not account for the poor performance of the control rats in a noisy environment. A reorganized auditory map may therefore have served as the neural substrate for the consistent performance of the noise-exposed rats in a noisy environment. PMID:22973201

  13. Female Flinders Sensitive Line rats show estrous cycle-independent depression-like behavior and altered tryptophan metabolism.

    PubMed

    Eskelund, Amanda; Budac, David P; Sanchez, Connie; Elfving, Betina; Wegener, Gregers

    2016-08-01

    Clinical studies suggest a link between depression and dysfunctional tryptophan (TRP) metabolism. Even though depression is twice as prevalent in women as men, the impact of the estrous cycle on TRP metabolism is not well-understood. Here we investigated 13 kynurenine and serotonin metabolites in female Flinders Sensitive Line (FSL) rats, a genetic rat model of depression. FSL rats and controls (Flinders Resistant Line rats), 12-20weeks old, were subject to the forced swim test (FST), a commonly used measure of depression-like behavior. Open field was used to evaluate locomotor ability and agoraphobia. Subsequently, plasma and hemispheres were collected and analyzed for their content of TRP metabolites using liquid chromatography-tandem mass spectrometry. Vaginal saline lavages were obtained daily for ⩾2 cycles. To estimate the effects of sex and FST we included plasma from unhandled, naïve male FSL and FRL rats. Female FSL rats showed a depression-like phenotype with increased immobility in the FST, not confounded by anxiety. In the brain, 3-hydroxykynurenine was increased whereas anthranilate and 5-hydroxytryptophan were decreased. In plasma, anthranilate and quinolinate levels were lower in FSL rats compared to the control line, independent of sex and FST. The estrous cycle neither impacted behavior nor TRP metabolite levels in the FSL rat. In conclusion, the female FSL rat is an interesting preclinical model of depression with altered TRP metabolism, independent of the estrous cycle. The status of the pathway in brain was not reflected in the plasma, which may indicate that an inherent local, cerebral regulation of TRP metabolism occurs. PMID:27210075

  14. Deprivation of endogenous brain-derived neurotrophic factor results in impairment of spatial learning and memory in adult rats.

    PubMed

    Mu, J S; Li, W P; Yao, Z B; Zhou, X F

    1999-07-24

    Brain-derived neurotrophic factor (BDNF) is abundantly expressed in the hippocampus and cerebral cortex and is involved in synaptic plasticity and long-term potentiation (LTP). The present study was under taken to investigate whether endogenous BDNF was required for spatial learning and memory in a rat model. Antibodies to BDNF (anti-BDNF, n=7) or control immunoglobulin G (control, n=6) were delivered into the rat brain continuously for 7 days with an osmotic pump. The rats were then subjected to a battery of behavioral tests. The results show that the average escape latencies in the BDNF antibody treated group were dramatically longer than those of the control (F=13.3, p<0.001). The rats treated with control IgG swam for a significantly longer distance in the P quadrant (where the escape plane had been placed) compared with the other three quadrants (p<0.05). In contrast, anti-BDNF-treated rats swam an equivalent distance in all four quadrants. The average percentage of swimming distance in the P quadrant by anti-BDNF-treated rats was much less than that by control IgG treated rats (p<0.001). These results suggest that endogenous BDNF is required for spatial learning and memory in adult rats.

  15. Sex differences in anxiety-like behavior and locomotor activity following prenatal and postnatal methamphetamine exposure in adult rats.

    PubMed

    Hrubá, L; Schutová, B; Šlamberová, R

    2012-01-18

    The aim of the present study was to investigate the impact of prenatal and postnatal methamphetamine (MA) exposure on behavior and anxiety in adult male and female rats. Mothers were daily exposed to injection of MA (5 mg/kg) or saline (S): prior to impregnation and throughout gestation and lactation periods. On postnatal day 1, pups were cross-fostered so that each mother raised 6 saline-exposed pups and 6 MA-exposed pups. Based on the prenatal and postnatal exposure 4 experimental groups (S/S, S/MA, MA/S, MA/MA) were tested in the Open field (OF) and in the Elevated plus maze (EPM) in adulthood. Locomotion, exploration, immobility and comforting behavior were evaluated in the OF, while anxiety was assessed in the EPM. While prenatal MA exposure did not affect behavior and anxiety in adulthood, postnatal MA exposure (i.e. MA administration to lactating mothers) induced long-term changes. Specifically, adult female rats in diestrus and adult males postnatally exposed to MA via breast milk (S/MA and MA/MA) had decreased locomotion and exploratory behavior in the OF and showed increased anxiety-like behavior in the EPM when compared to female rats in diestrus or males postnatally exposed to saline (S/S and MA/S). In adult females in proestrus, postnatal exposure to MA affected only exploratory behavior in the OF when compared to rats in proestrus postnatally exposed to saline. Thus, the present study shows that postnatal exposure to MA via breast milk impairs behavior in unfamiliar environment and anxiety-like behavior of adult male and female rats more than prenatal MA exposure. PMID:21884713

  16. Resurgence of response sequences during extinction in rats shows a primacy effect.

    PubMed

    Reed, Phil; Morgan, Theresa A

    2006-11-01

    Rats were trained to emit a series of three-response sequences to a criterion (i.e., more than 80% of all emitted sequences correct over five successive sessions). Each rat was trained on a series of different, three-response sequences. After the final three-response sequence was acquired, two extinction tests were administered, and the three-response sequences that re-emerged during these extinction tests were noted. Resurgence effects during extinction were observed; that is, the previously trained sequences were emitted. These resurgence effects followed an orderly pattern, which involved a primacy effect. The rats initially emitted the immediately previously trained response, but then started to emit the response sequence they first were trained to emit. Thus, resurgence behavior during extinction can be an orderly function of previous training history. These results replicate those previously obtained with human subjects.

  17. A case of adult moyamoya disease showing progressive angiopathy on cerebral angiography.

    PubMed

    Shirane, R; Mikawa, S; Ebina, T

    1999-09-01

    In moyamoya disease, progression of carotid occlusive lesion in an adult patient is very rare. We report a case of adult moyamoya disease with acute angiographical stage progression and hemodynamic deterioration. A 56-year-old female complaining of left motor weakness visited our department. On MRI, infarct lesion was found in the right white matter. On cerebral angiography, occlusive lesions in the bilateral internal carotid arterial siphons and moyamoya vessels were found. The right side was stage V and the left side was stage III. On IMP-SPECT, decreased cerebral hemodynamic reserve of the right cerebral hemisphere was found. In this patient, right STA-MCA anastomosis was performed. After operation, she became possible to walk and discharged to home. Five months after operation, good collateral formation and improvement of hemodynamic reserve in the right hemisphere were found. However, on left carotid arteriography, the anterior and middle cerebral arteries were only slightly imaged, and the disease state progressed to stage IV. In addition, decreased blood flow and hemodynamic reserve were appeared in the left hemisphere.

  18. Effects of fasting and/or oxidizing and reducing agents on absorption of neptunium from the gastrointestinal tract of mice and adult or neonatal rats.

    PubMed

    Sullivan, M F; Ruemmler, P S; Ryan, J L

    1984-12-01

    Neptunium-237(V) nitrate was administered by gavage to groups of fed or fasted adult and 5-day-old rats. Some groups also received the oxidants quinhydrone or ferric iron, and others received the reducing agent ferrous iron. Adult mice received ferric or ferrous iron and 235Np. When the adult rats were killed at 7 days after gavage, measurements showed that, compared with rats that were fed, a 24-hr fast caused a fivefold increase in 237Np absorption and retention. Both quinhydrone and ferric iron caused an even greater increase in absorption in both fed and fasted rats. Ferrous iron, on the other hand, decreased absorption in fasted rats to values lower than those obtained in fed rats. Similar results were obtained in mice treated with 235Np and either ferric or ferrous iron. The highest absorption obtained after gavage of ferric iron to fasted rats and mice was about two orders of magnitude higher than the value obtained in animals that were fed before gavage. The effects of ferric and ferrous iron on neptunium absorption by neonatal rats were similar to their effects on adult animals but of lesser magnitude. These results are consistent with the hypothesis that Np(V), when given in small mass quantities to fed animals, is reduced in the gastrointestinal tract to Np(IV), which is less well absorbed than Np(V).

  19. Inhibition of acetylcholinesterase activity in brain and behavioral analysis in adult rats after chronic administration of fenproporex.

    PubMed

    Rezin, Gislaine T; Scaini, Giselli; Ferreira, Gabriela K; Cardoso, Mariane R; Gonçalves, Cinara L; Constantino, Larissa S; Deroza, Pedro F; Ghedim, Fernando V; Valvassori, Samira S; Resende, Wilson R; Quevedo, João; Zugno, Alexandra I; Streck, Emilio L

    2012-12-01

    Fenproporex is an amphetamine-based anorectic and it is rapidly converted in vivo into amphetamine. It elevates the levels of extracellular dopamine in the brain. Acetylcholinesterase is a regulatory enzyme which is involved in cholinergic synapses and may indirectly modulate the release of dopamine. Thus, we investigated whether the effects of chronic administration of fenproporex in adult rats alters acquisition and retention of avoidance memory and acetylcholinesterase activity. Adult male Wistar rats received repeated (14 days) intraperitoneal injection of vehicle or fenproporex (6.25, 12.5 or 25 mg/kg i.p.). For behavioral assessment, animals were submitted to inhibitory avoidance (IA) tasks and continuous multiple trials step-down inhibitory avoidance (CMIA). Acetylcholinesterase activity was measured in the prefrontal cortex, hippocampus, hypothalamus and striatum. The administration of fenproporex (6.25, 12.5 and 25 mg/kg) did not induce impairment in short and long-term IA or CMIA retention memory in rats. In addition, longer periods of exposure to fenproporex administration decreased acetylcholinesterase activity in prefrontal cortex and striatum of rats, but no alteration was verified in the hippocampus and hypothalamus. In conclusion, the present study showed that chronic fenproporex administration decreased acetylcholinesterase activity in the rat brain. However, longer periods of exposure to fenproporex did not produce impairment in short and long-term IA or CMIA retention memory in rats. PMID:22832793

  20. Diethylene glycol-induced toxicities show marked threshold dose response in rats

    SciTech Connect

    Landry, Greg M.; Dunning, Cody L.; Abreo, Fleurette; Latimer, Brian; Orchard, Elysse; McMartin, Kenneth E.

    2015-02-01

    Diethylene glycol (DEG) exposure poses risks to human health because of widespread industrial use and accidental exposures from contaminated products. To enhance the understanding of the mechanistic role of metabolites in DEG toxicity, this study used a dose response paradigm to determine a rat model that would best mimic DEG exposure in humans. Wistar and Fischer-344 (F-344) rats were treated by oral gavage with 0, 2, 5, or 10 g/kg DEG and blood, kidney and liver tissues were collected at 48 h. Both rat strains treated with 10 g/kg DEG had equivalent degrees of metabolic acidosis, renal toxicity (increased BUN and creatinine and cortical necrosis) and liver toxicity (increased serum enzyme levels, centrilobular necrosis and severe glycogen depletion). There was no liver or kidney toxicity at the lower DEG doses (2 and 5 g/kg) regardless of strain, demonstrating a steep threshold dose response. Kidney diglycolic acid (DGA), the presumed nephrotoxic metabolite of DEG, was markedly elevated in both rat strains administered 10 g/kg DEG, but no DGA was present at 2 or 5 g/kg, asserting its necessary role in DEG-induced toxicity. These results indicate that mechanistically in order to produce toxicity, metabolism to and significant target organ accumulation of DGA are required and that both strains would be useful for DEG risk assessments. - Highlights: • DEG produces a steep threshold dose response for kidney injury in rats. • Wistar and F-344 rats do not differ in response to DEG-induced renal injury. • The dose response for renal injury closely mirrors that for renal DGA accumulation. • Results demonstrate the importance of DGA accumulation in producing kidney injury.

  1. Thermoregulatory deficits in adult Long Evans rat exposed perinatally to the antithyroidal drug, propylthiouracil.

    PubMed

    Johnstone, Andrew F M; Gilbert, Mary E; Aydin, Cenk; Grace, Curtis E; Hasegawa, Masashi; Gordon, Christopher J

    2013-01-01

    Developmental exposure to endocrine disrupting drugs and environmental toxicants has been shown to alter a variety of physiological processes in mature offspring. Body (core) temperature (T(c)) is a tightly regulated homeostatic system but is susceptible to disruptors of the hypothalamic pituitary thyroid (HPT) axis. We hypothesized that thermoregulation would be disrupted in adult offspring exposed perinatally to an HPT disruptor. Propylythiouracil (PTU) was used as a prototypical compound because of its well known antithyroidal properties. PTU was added to the drinking water of pregnant rats in concentrations of 0, 1, 2, 3, and 10 ppm from gestational day (GD) 6 through postnatal day (PND) 21. Adult male offspring were implanted with radiotransmitters to monitor Tc and motor activity (MA) and were observed undisturbed at an ambient temperature of 22 °C for 12 consecutive days. Data were averaged into a single 24 hour period to minimize impact of ultradian changes in T(c) and MA. All treatment groups showed a distinct circadian temperature rhythm. Rats exposed to 10 ppm PTU exhibited a marked deviation in their regulated T(c) with a reduction of approximately 0.4 °C below that of controls throughout the daytime period and a smaller reduction at night. Rats exposed to 1 or 2 ppm also had smaller but significant reductions in T(c). MA was unaffected by PTU. Overall, developmental exposure to moderate doses of an antithyroidal drug led to an apparent permanent reduction in T(c) of adult offspring that was independent of changes in MA. PMID:23732561

  2. Evaluation of possible toxic effects of spearmint (Mentha spicata) on the reproductive system, fertility and number of offspring in adult male rats

    PubMed Central

    Nozhat, Fatemeh; Alaee, Sanaz; Behzadi, Khodabakhsh; Azadi Chegini, Najmeh

    2014-01-01

    Objective: In this study we investigated the effects of spearmint (Mentha spicata Labiatae) on the reproductive system, fertility and number of offspring in adult male rats. Materials and Methods: Adult Wistar male rats in one control (C) and three experimental groups (I, II and III) received 0, 10, 20 and 40 mg/kg spearmint extract orally for 45 days, respectively. Following this treatment, the animals’ weights, and the standard weight of reproductive tissues, sperm count, sperm motility and serum testosterone concentration were measured, and reproductive tissues were examined histopathologically. To evaluate the effects of spearmint on fertility of male rats and growth of their offspring, male rats of the control and experimental groups mated with untreated female rats. Results: Results showed that spearmint did not affect the rats’ body and reproductive tissue weights. The sperm count, fast and slow progressive motility of sperm and serum testosterone concentration decreased while number of non-progressive sperm and immotile sperm increased in the experimental groups compared to the control group, but none of these changes were statistically significant. Histopathological studies showed no severe changes in reproductive tissues between control and experimental groups. Number and growth of offspring born from mating of male rats with untreated female rats showed no difference. Conclusion: We concluded that spearmint has no significant toxic effect on the reproductive system, fertility and number of offspring in adult male rats at the above mentioned dose levels. However high levels of this extract may have adverse effects on male fertility. PMID:25386406

  3. Perinatal undernutrition facilitates morphine sensitization and cross-sensitization to cocaine in adult rats: a behavioral and neurochemical study.

    PubMed

    Velazquez, E E; Valdomero, A; Orsingher, O A; Cuadra, G R

    2010-01-20

    The development of sensitization to the locomotor effects of morphine and cross-sensitization between morphine and cocaine were evaluated in adult rats submitted to a protein malnutrition schedule from the 14th day of gestation up to 30 days of age (D-rats), and compared with well-nourished animals (C-rats). Dose-response curves to morphine-induced locomotor activity (5, 7.5, 10 or 15 mg/kg, i.p., every other day for 5 days) revealed a shift to the left in D-rats compared to C-rats. This implies that D-rats showed behavioral sensitization to the lower dose of morphine used (5 mg/kg), which was ineffective in C-rats. Furthermore, when a cocaine challenge (10 mg/kg, i.p) was given 48 h after the last morphine administration, only D-rats exhibited cross-sensitization in morphine-pretreated animals (7.5 and 10 mg/kg). In order to correlate the differential response observed with the functioning of the mesocorticolimbic dopaminergic system, extracellular dopamine (DA) levels were measured in the nucleus accumbens (core and shell) and the dorsal caudate-putamen. A challenge with cocaine in morphine pre-exposed animals produced an increase in DA release, but only in the nucleus accumbens "core" of D-rats. Similar DA levels were found in the nucleus accumbens "shell" and in the dorsal caudate-putamen of both groups. Finally, these results demonstrate that D-rats had a lower threshold for developing both a progressive behavioral sensitization to morphine and a cross-sensitization to cocaine. In accordance with these behavioral findings, a higher responsiveness of the nucleus accumbens core, expressed by increased DA levels, both basal and after cocaine challenge, was observed in D-rats.

  4. Maternal exposure to cadmium during gestation perturbs the vascular system of the adult rat offspring

    SciTech Connect

    Ronco, Ana Maria; Montenegro, Marcela; Castillo, Paula; Urrutia, Manuel; Saez, Daniel; Hirsch, Sandra; Zepeda, Ramiro; Llanos, Miguel N.

    2011-03-01

    Several cardiovascular diseases (CVD) observed in adulthood have been associated with environmental influences during fetal growth. Here, we show that maternal exposure to cadmium, a ubiquitously distributed heavy metal and main component of cigarette smoke is able to induce cardiovascular morpho-functional changes in the offspring at adult age. Heart morphology and vascular reactivity were evaluated in the adult offspring of rats exposed to 30 ppm of cadmium during pregnancy. Echocardiographic examination shows altered heart morphology characterized by a concentric left ventricular hypertrophy. Also, we observed a reduced endothelium-dependent reactivity in isolated aortic rings of adult offspring, while endothelium-independent reactivity remained unaltered. These effects were associated with an increase of hem-oxygenase 1 (HO-1) expression in the aortas of adult offspring. The expression of HO-1 was higher in females than males, a finding likely related to the sex-dependent expression of the vascular cell adhesion molecule 1 (VCAM-1), which was lower in the adult female. All these long-term consequences were observed along with normal birth weights and absence of detectable levels of cadmium in fetal and adult tissues of the offspring. In placental tissues however, cadmium levels were detected and correlated with increased NF-{kappa}B expression - a transcription factor sensitive to inflammation and oxidative stress - suggesting a placentary mechanism that affect genes related to the development of the cardiovascular system. Our results provide, for the first time, direct experimental evidence supporting that exposure to cadmium during pregnancy reprograms cardiovascular development of the offspring which in turn may conduce to a long term increased risk of CVD.

  5. Resveratrol shows neuronal and vascular-protective effects in older, obese, streptozotocin-induced diabetic rats.

    PubMed

    Phyu, Hnin Ei; Irwin, Jordon Candice; Vella, Rebecca Kate; Fenning, Andrew Stuart

    2016-06-01

    Diabetes-induced CVD is the most significant complication of prolonged hyperglycaemia. The aim of this study was to determine whether resveratrol, a polyphenol antioxidant compound, when administered at a dose that can be reasonably obtained through supplementation could prevent the development of cardiovascular complications in older, obese, diabetic rats. Diabetes was induced in 6-month old, obese, male Wistar rats via a single intravenous dose of streptozotocin (65 mg/kg). Randomly selected animals were administered resveratrol (2 mg/kg) via oral gavage daily for 8 weeks. Body weights, blood glucose levels, food intake and water consumption were monitored, and assessments of vascular reactivity, tactile allodynia and left ventricular function were performed. Resveratrol therapy significantly improved tactile allodynia and vascular contractile functionality in diabetic rats (P<0·05). There were no significant changes in standardised vasorelaxation responses, plasma glucose concentrations, water consumption, body weight, left ventricular hypertrophy, kidney hypertrophy, heart rate or left ventricular compliance with resveratrol administration. Resveratrol-mediated improvements in vascular and nerve function in old, obese, diabetic rats were associated with its reported antioxidant effects. Resveratrol did not improve cardiac function nor mitigate the classic clinical symptoms of diabetes mellitus (i.e. hyperglycaemia, polydypsia and a failure to thrive). This suggests that supplementation with resveratrol at a dose achievable with commercially available supplements would not produce significant cardioprotective effects in people with diabetes mellitus.

  6. Resveratrol shows neuronal and vascular-protective effects in older, obese, streptozotocin-induced diabetic rats.

    PubMed

    Phyu, Hnin Ei; Irwin, Jordon Candice; Vella, Rebecca Kate; Fenning, Andrew Stuart

    2016-06-01

    Diabetes-induced CVD is the most significant complication of prolonged hyperglycaemia. The aim of this study was to determine whether resveratrol, a polyphenol antioxidant compound, when administered at a dose that can be reasonably obtained through supplementation could prevent the development of cardiovascular complications in older, obese, diabetic rats. Diabetes was induced in 6-month old, obese, male Wistar rats via a single intravenous dose of streptozotocin (65 mg/kg). Randomly selected animals were administered resveratrol (2 mg/kg) via oral gavage daily for 8 weeks. Body weights, blood glucose levels, food intake and water consumption were monitored, and assessments of vascular reactivity, tactile allodynia and left ventricular function were performed. Resveratrol therapy significantly improved tactile allodynia and vascular contractile functionality in diabetic rats (P<0·05). There were no significant changes in standardised vasorelaxation responses, plasma glucose concentrations, water consumption, body weight, left ventricular hypertrophy, kidney hypertrophy, heart rate or left ventricular compliance with resveratrol administration. Resveratrol-mediated improvements in vascular and nerve function in old, obese, diabetic rats were associated with its reported antioxidant effects. Resveratrol did not improve cardiac function nor mitigate the classic clinical symptoms of diabetes mellitus (i.e. hyperglycaemia, polydypsia and a failure to thrive). This suggests that supplementation with resveratrol at a dose achievable with commercially available supplements would not produce significant cardioprotective effects in people with diabetes mellitus. PMID:27153202

  7. Characterization of motor units in behaving adult mice shows a wide primary range.

    PubMed

    Ritter, Laura K; Tresch, Matthew C; Heckman, C J; Manuel, Marin; Tysseling, Vicki M

    2014-08-01

    The mouse is essential for genetic studies of motor function in both normal and pathological states. Thus it is important to consider whether the structure of motor output from the mouse is in fact analogous to that recorded in other animals. There is a striking difference in the basic electrical properties of mouse motoneurons compared with those in rats, cats, and humans. The firing evoked by injected currents produces a unique frequency-current (F-I) function that emphasizes recruitment of motor units at their maximum force. These F-I functions, however, were measured in anesthetized preparations that lacked two key components of normal synaptic input: high levels of synaptic noise and neuromodulatory inputs. Recent studies suggest that the alterations in the F-I function due to these two components are essential for recreating firing behavior of motor units in human subjects. In this study we provide the first data on firing patterns of motor units in the awake mouse, focusing on steady output in quiet stance. The resulting firing patterns did not match the predictions from the mouse F-I behaviors but instead revealed rate modulation across a remarkably wide range (10-60 Hz). The low end of the firing range may be due to changes in the F-I relation induced by synaptic noise and neuromodulatory inputs. The high end of the range may indicate that, unlike other species, quiet standing in the mouse involves recruitment of relatively fast-twitch motor units. PMID:24805075

  8. Rats with congenital learned helplessness respond less to sucrose but show no deficits in activity or learning.

    PubMed

    Vollmayr, Barbara; Bachteler, Daniel; Vengeliene, Valentina; Gass, Peter; Spanagel, Rainer; Henn, Fritz

    2004-04-01

    Inbred rat strains for congenital learned helplessness (cLH) and for congenital resistance to learned helplessness (cNLH) were investigated as a model to study genetic predisposition to major depression. Congenitally helpless rats respond less to sucrose under a progressive ratio schedule. This is not confounded by locomotor hypoactivity: in contrast, cLH rats show a slight hyperactivity during the first 5 min of an open field test. cLH rats acquire operant responding to sucrose as readily as cNLH rats and exhibit normal memory acquisition and retrieval in the Morris water maze, thus ruling out general learning deficits as the cause of the decreased response to sucrose. Reduced total responses and reduced breaking points for sucrose in the cLH strain argue for anhedonia, which is an analogue to loss of pleasure essential for the diagnosis of major depressive episodes, and thus confirm the validity of congenitally learned helpless rats as a model of major depression.

  9. Voluntary and involuntary running in the rat show different patterns of theta rhythm, physical activity, and heart rate.

    PubMed

    Li, Jia-Yi; Kuo, Terry B J; Yen, Jiin-Cherng; Tsai, Shih-Chih; Yang, Cheryl C H

    2014-05-01

    Involuntarily exercising rats undergo more physical and mental stress than voluntarily exercising rats; however, these findings still lack electrophysiological evidence. Many studies have reported that theta rhythm appears when there is mental stress and that it is affected by emotional status. Thus we hypothesized that the differences between voluntary and involuntary movement should also exist in the hippocampal theta rhythm. Using the wheel and treadmill exercise models as voluntary and involuntary exercise models, respectively, this study wirelessly recorded the hippocampal electroencephalogram, electrocardiogram, and three-dimensional accelerations of young male rats. Treadmill and wheel exercise produced different theta patterns in the rats before and during running. Even though the waking baselines for the two exercise types were recorded in different environments, there did not exist any significant difference after distinguishing the rats' sleep/wake status. When the same movement-related parameters are considered, the treadmill running group showed more changes in their theta frequency (4-12 Hz), in their theta power between 9.5-12 Hz, and in their heart rate than the wheel running group. A positive correlation between the changes in high-frequency (9.5-12 Hz) theta power and heart rate was identified. Our results reveal various voluntary and involuntary changes in hippocampal theta rhythm as well as divergences in heart rate and high-frequency theta activity that may represent the effects of an additional emotional state or the sensory interaction during involuntary running by rats. PMID:24623507

  10. Nocturnal food-related hyperdipsia in the adult spontaneously hypertensive rat.

    PubMed

    Kraly, F S; Moore, A F; Miller, L A; Drexler, A

    1982-05-01

    Male adult spontaneously hypertensive rats (SHR) ate the same but drank more and had a higher water to food ratio (W:F) than did Wistar-Kyoto (WKY) rats in 24-hr when they had continuous access to standard laboratory pellets and tap water. When rats ate in the day phase of a 12:12 light/dark cycle after 24-hr food deprivation, SHR rats ate and drank the same ad did WKY rats in a 60-min test. When the same rats ate at night after 24-hr food deprivation, however, SHR rats were hyperdipsic: They ate the same as did WKY rats, but SHR rats drank more and had a higher W:F. This relative hyperdipsia reflected the increased ability of ingestion of food to stimulate drinking in SHR, because when food was absent for a 60-min test at night SHR drank the same as did WKY rats. Three dipsogens which are candidate components for eating-elicited drinking in the rat, cellular dehydration, histamine and angiotensin II, elicited drinking differentially in SHR and WKY rats: SHR drank more than did WKY rats in response to (1) cellular dehydration produced by IP hypertonic saline, (2) large doses of SC histamine, and (3) SC angiotensin II. These results demonstrate that SHR exhibit a nocturnal food-related hyperdipsia which may reflect differential sensitivity to stimuli important for eating-elicited drinking such as increased osmolality and endogenous histamine or angiotensin.

  11. Brain-derived neurotrophic factor heterozygous mutant rats show selective cognitive changes and vulnerability to chronic corticosterone treatment.

    PubMed

    Gururajan, A; Hill, R A; van den Buuse, M

    2015-01-22

    Brain-derived neurotrophic factor (BDNF) is a widely expressed neurotrophin involved in neurodevelopment, neuroprotection and synaptic plasticity. It is also implicated in a range of psychiatric disorders such as schizophrenia, depression and post-traumatic stress disorder. Stress during adolescence/young adulthood can have long-term psychiatric and cognitive consequences, however it is unknown how altered BDNF signaling is involved in such effects. Here we investigated whether a congenital deficit in BDNF availability in rats increases vulnerability to the long-term effects of the stress hormone, corticosterone (CORT). Compared to wildtype (WT) littermates, BDNF heterozygous (HET) rats showed higher body weights and minor developmental changes, such as reduced relative brain and pituitary weight. These animals furthermore showed deficits in short-term spatial memory in the Y-maze and in prepulse inhibition and startle, but not in object-recognition memory. CORT treatment induced impairments in novel-object recognition memory in both genotypes but disrupted fear conditioning extinction learning in BDNF HET rats only. These results show selective behavioral changes in BDNF HET rats, at baseline or after chronic CORT treatment and add to our understanding of the role of BDNF and its interaction with stress. Importantly, this study demonstrates the utility of the BDNF HET rat in investigations into the pathophysiology of various psychiatric disorders.

  12. Differences in Response Initiation and Behavioral Flexibility Between Adolescent and Adult Rats

    PubMed Central

    Simon, Nicholas W.; Gregory, Timothy A.; Wood, Jesse; Moghaddam, Bita

    2014-01-01

    Adolescence is a period of increased vulnerability to psychiatric illnesses such as addiction, mood disorders, and schizophrenia. Rats provide a useful animal model for investigating the differences in behavior and biology between adults and adolescents that stem from ongoing brain development. We developed the Cued Response Inhibition Task, or CRIT, to assess response inhibition and initiation processes by measuring the ability of rodents to withhold a response during an inhibitory cue and then to respond promptly after cue termination. We found no difference between adult and adolescent rats in the ability to appropriately inhibit a response during cue presentation. Adolescents, however, were unable to initiate a response as quickly as adults after cue termination. Further, we observed that this difference in responding was abolished after adolescent rats aged to adulthood with no additional training. In a separate experiment, adult and adolescent rats were trained in CRIT and then trained in another protocol in which the response inhibitory cue from CRIT was used as a Pavlovian cue predictive of reward. Adolescents demonstrated more reward-seeking behavior during the previously inhibitory Pavlovian cue than adults, indicative of greater behavioral flexibility. Taken together, these data suggest that, compared with adults, adolescent rats (a) are less able to initiate a response after response inhibition, (b) equally inhibit behavioral responses, and (c) are more adept at flexibly switching behavioral patterns. Furthermore, this study characterizes a task that is well suited for future pharmacological and electrophysiological investigations for assessing neuronal processing differences between adolescents and adults. PMID:23398439

  13. Accumulation of glycogen in axotomized adult rat facial motoneurons.

    PubMed

    Takezawa, Yosuke; Baba, Otto; Kohsaka, Shinichi; Nakajima, Kazuyuki

    2015-06-01

    This study biochemically determined glycogen content in the axotomized facial nucleus of adult rats up to 35 days postinsult. The amounts of glycogen in the transected facial nucleus were significantly increased at 5 days postinsult, peaked at 7 days postinsult, and declined to the control levels at 21-35 days postinsult. Immunohistochemical analysis with antiglycogen antibody revealed that the quantity of glycogen granules in the axotomized facial nucleus was greater than that in the control nucleus at 7 days postinjury. Dual staining methods with antiglycogen antibody and a motoneuron marker clarified that the glycogen was localized mainly in motoneurons. Immunoblotting and quantification analysis revealed that the ratio of inactive glycogen synthase (GS) to total GS was significantly decreased in the injured nucleus at about 1-3 days postinsult and significantly increased from 7 to 14 days postinsult, suggesting that glycogen is actively synthesized in the early period postinjury but suppressed after 7 days postinsult. The enhanced glycogen at about 5-7 days postinsult is suggested to be responsible for the decrease in inactive GS levels, and the decrease of glycogen after 7 days postinsult is considered to be caused by increased inactive GS levels and possibly the increase in active glycogen phosphorylase.

  14. Effects of adult dysthyroidism on the morphology of hippocampal granular cells in rats.

    PubMed

    Martí-Carbonell, Maria Assumpció; Garau, Adriana; Sala-Roca, Josefina; Balada, Ferran

    2012-01-01

    Thyroid hormones are essential for normal brain development and very important in the normal functioning of the brain. Thyroid hormones action in the adult brain has not been widely studied. The effects of adult hyperthyroidism are not as well understood as adult hypothyroidism, mainly in hippocampal granular cells. The purpose of the present study is to assess the consequences of adult hormone dysthyroidism (excess/deficiency of TH) on the morphology of dentate granule cells in the hippocampus by performing a quantitative study of dendritic arborizations and dendritic spines using Golgi impregnated material. Hypo-and hyperthyroidism were induced in rats by adding 0.02 percent methimazole and 1 percent L-thyroxine, respectively, to drinking water from 40 days of age. At 89 days, the animals' brains were removed and stained by a modified Golgi method and blood samples were collected in order to measure T4 serum levels. Neurons were selected and drawn using a camera lucida. Our results show that both methimazole and thyroxine treatment affect granule cell morphology. Treatments provoke alterations in the same direction, namely, reduction of certain dendritic-branching parameters that are more evident in the methimazole than in the thyroxine group. We also observe a decrease in spine density in both the methimazole and thyroxine groups. PMID:23093010

  15. Synergistic effect of estradiol and fluoxetine in young adult and middle-aged female rats in two models of experimental depression.

    PubMed

    Récamier-Carballo, Soledad; Estrada-Camarena, Erika; Reyes, Rebeca; Fernández-Guasti, Alonso

    2012-08-01

    The antidepressant effect of estrogens combined with antidepressants is controversial: some preclinical data showed that estrogens facilitate the effect of antidepressants in the forced swimming test (FST) in young adult rats, while others failed to find such effect in middle-aged rats in the chronic mild stress (CMS) model. In clinics similar differences were reported and may be due to the compounds, the depression model or type of depression, the experimental design, and the age of the subjects or the women's menopause stage. The objective of this study was to analyze the antidepressant-like effect of the combination of 17β-estradiol (E(2)) and fluoxetine (FLX) in young adults (2-4 months) and middle-aged (12-14 months) ovariectomized (OVX) rats in two experimental models: FST and CMS. E(2) (5 and 10 μg/rat) and FLX (2.5 and 10 mg/kg) per se dose-dependently reduced immobility in both age groups and, in young adults both compounds increased swimming, whereas in middle-aged rats they increased swimming and climbing. Analysis of the antidepressant-like effect of the combination of suboptimal doses of FLX (1.25 mg/kg) and E(2) (2.5 μg/rat) showed a decrease in immobility and an increase in swimming in both age groups. In the CMS, chronic E(2) (2.5 μg/rat) with FLX (1.25 mg/kg) augmented relative sucrose intake, but middle-aged rats responded 2 weeks earlier than young adults. These results show that the antidepressant-like effect of the combination of E(2) and FLX in young adult and middle-aged female rats is evidenced in the two animal models of depression: FST and CMS.

  16. The impact of emotional stress early in life on adult voluntary ethanol intake-results of maternal separation in rats.

    PubMed

    Roman, Erika; Nylander, Ingrid

    2005-09-01

    The combination of genetic and environmental factors determines the individual vulnerability for excessive ethanol intake, possibly leading to dependence. The environmental influences early in life represent examples of determinant factors for adult behaviour and can be protective as well as risk factors. Maternal separation is one model to examine the long-term consequences of early environmental experiences on neurochemistry and behaviour, including drug-taking behaviour in experimental animals. In the present review, findings from studies using repeated short and prolonged periods of maternal separation, with emphasis on effects on voluntary ethanol intake in rats with or without a genetic predisposition for high voluntary ethanol intake, are summarized. Despite some contradictory results, the general picture emerging shows that short periods of maternal separation during the postnatal period result in a lower adult voluntary ethanol intake in male rats. Prolonged periods of maternal separation were found to induce a high voluntary ethanol intake in male rats, including rats with a genetic predisposition for high ethanol intake. Results from the literature also show that changes were not just related to time of separation but were also related to the degree of handling. Interestingly, in terms of voluntary ethanol intake, female rats were generally not affected by postnatal maternal separation. The reasons for these sex differences need further investigation. In terms of neurobiological consequences of maternal separation, conclusive data are sparse and one of the future challenges will, therefore, be to identify and characterize underlying neurobiological mechanisms, especially in the individual animal.

  17. GAS1 is present in the cerebrospinal fluid and is expressed in the choroid plexus of the adult rat.

    PubMed

    Ayala-Sarmiento, Alberto E; Estudillo, Enrique; Pérez-Sánchez, Gilberto; Sierra-Sánchez, Arturo; González-Mariscal, Lorenza; Martínez-Fong, Daniel; Segovia, José

    2016-09-01

    Growth arrest specific 1 (GAS1) is a GPI-anchored protein that inhibits proliferation when overexpressed in tumors but during development it promotes proliferation and survival of different organs and tissues. This dual ability is caused by its capacity to interact both by inhibiting the signaling induced by the glial cell line-derived neurotrophic factor and by facilitating the activity of the sonic hedgehog pathway. GAS1 is expressed as membrane bound in different organs and as a secreted form by glomerular mesangial cells. In the developing central nervous system, GAS1 is found in neural progenitors; however, it continues to be expressed in the adult brain. Here, we demonstrate that soluble GAS1 is present in the cerebrospinal fluid (CSF) and it is expressed in the choroid plexus (CP) of the adult rat, the main producer of CSF. Additionally, we confirm the presence of GAS1 in blood plasma and liver of the adult rat, the principal source of blood plasma proteins. The pattern of expression of GAS1 is perivascular in both the CP and the liver. In vitro studies show that the fibroblast cell line NIH/3T3 expresses one form of GAS1 and releases two soluble forms into the supernatant. Briefly, in the present work, we show the presence of GAS1 in adult rat body fluids focusing in the CSF and the CP, and suggest that secreted GAS1 exists as two different isoforms. PMID:27225491

  18. The effects of early-life predator stress on anxiety- and depression-like behaviors of adult rats.

    PubMed

    Chen, Lu-jing; Shen, Bing-qing; Liu, Dan-dan; Li, Sheng-tian

    2014-01-01

    Childhood emotional trauma contributes significantly to certain psychopathologies, such as post-traumatic stress disorder. In experimental animals, however, whether or not early-life stress results in behavioral abnormalities in adult animals still remains controversial. Here, we investigated both short-term and long-term changes of anxiety- and depression-like behaviors of Wistar rats after being exposed to chronic feral cat stress in juvenile ages. The 2-week predator stress decreased spontaneous activities immediately following stress but did not increase depression- or anxiety-like behaviors 4 weeks after the stimulation in adulthood. Instead, juvenile predator stress had some protective effects, though not very obvious, in adulthood. We also exposed genetic depression model rats, Wistar Kyoto (WKY) rats, to the same predator stress. In WKY rats, the same early-life predator stress did not enhance anxiety- or depression-like behaviors in both the short-term and long-term. However, the stressed WKY rats showed slightly reduced depression-like behaviors in adulthood. These results indicate that in both normal Wistar rats and WKY rats, early-life predator stress led to protective, rather than negative, effects in adulthood. PMID:24839560

  19. 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.

  20. Testicular hormones do not regulate sexually dimorphic Pavlovian fear conditioning or perforant-path long-term potentiation in adult male rats.

    PubMed

    Anagnostaras, S G; Maren, S; DeCola, J P; Lane, N I; Gale, G D; Schlinger, B A; Fanselow, M S

    1998-04-01

    We recently reported that Pavlovian fear conditioning and hippocampal perforant-path long-term potentiation (LTP) are sexually dimorphic in rats. Males show greater contextual fear conditioning, which depends on the hippocampus, as well as greater hippocampal LTP. In order to examine the role of circulating gonadal hormones in adult male rats, animals were castrated in two experiments, and Pavlovian fear conditioning and in vivo perforant-path LTP were examined. It was found that sexually-dimorphic LTP and fear conditioning are not regulated by the activational effects of testicular hormones in adult male rats. That is, in every respect, castrated male rats were similar to intact male rats in Pavlovian fear conditioning and hippocampal LTP. It is likely that sexual dimorphism in this system is established earlier in development by the organizational effects of gonadal hormones.

  1. Lycium barbarum polysaccharides promotes in vivo proliferation of adult rat retinal progenitor cells

    PubMed Central

    Wang, Hua; Lau, Benson Wui-Man; Wang, Ning-li; Wang, Si-ying; Lu, Qing-jun; Chang, Raymond Chuen-Chung; So, Kwok-fai

    2015-01-01

    Lycium barbarum is a widely used Chinese herbal medicine prescription for protection of optic nerve. However, it remains unclear regarding the effects of Lycium barbarum polysaccharides, the main component of Lycium barbarum, on in vivo proliferation of adult ciliary body cells. In this study, adult rats were intragastrically administered low- and high-dose Lycium barbarum polysaccharides (1 and 10 mg/kg) for 35 days and those intragastrically administered phosphate buffered saline served as controls. The number of Ki-67-positive cells in rat ciliary body in the Lycium barbarum polysaccharides groups, in particular low-dose Lycium barbarum polysaccharides group, was significantly greater than that in the phosphate buffered saline group. Ki-67-positive rat ciliary body cells expressed nestin but they did not express glial fibrillary acidic protein. These findings suggest that Lycium barbarum polysaccharides can promote the proliferation of adult rat retinal progenitor cells and the proliferated cells present with neuronal phenotype. PMID:26889185

  2. [Comparative study of the long-term behavioral effects of noopept and piracetam in adult male rats and female rats in postnatal period].

    PubMed

    Voronina, T A; Guzevatykh, L S; Trofimov, S S

    2005-01-01

    Adult male and female rats were treated with the peptide nootrope drug noopept (daily dose, 0.1 mg/kg) and piracetam (200 mg/kg). In the period from 8th to 20th day, both drugs (cognitive enhancers) suppressed the horizontal and vertical activity and the anxiety in test animals as compared to the control group treated with 0.9 % aqueous NaCl solution. Early postnatal injections of the nootropes influenced neither the morphology development nor the behavior of adult female rats in the plus maze, extrapolational escape, passive avoidance, and pain sensitivity threshold tests. Animals in the "intact" group (having received neither drugs not physiological solution, that is, developing in a poor sensor environment), showed less pronounced habituation in the open field test as compared to the control and drug treated groups. PMID:15934357

  3. Hindlimb Stretching Alters Locomotor Function Post-Spinal Cord Injury in the Adult Rat

    PubMed Central

    Caudle, Krista L.; Atkinson, Darryn A.; Brown, Edward H.; Donaldson, Katie; Seibt, Erik; Chea, Tim; Smith, Erin; Chung, Karianne; Shum-Siu, Alice; Cron, Courtney C.; Magnuson, David S. K.

    2014-01-01

    Background Stretching is a widely accepted standard-of-care therapy following spinal cord injury that has not been systematically studied in animal models. Objective To investigate the influence of a daily stretch-based physical therapy program on locomotor recovery in adult rats with moderate T9 contusive SCI. Methods A randomized treatment and control study of stretching in an animal model of acute spinal cord injury (SCI). Moderate spinal cord injuries were delivered with the NYU Impactor. Daily stretching (30 min./day, 5 days/wk for 8 wks) was provided by a team of animal handlers. Hindlimb function was assessed using the BBB Open Field Locomotor Scale and kinematically. Passive range-of-motion for each joint was determined weekly using a goniometer. Results Declines in hindlimb function during overground stepping were observed for the first 4 weeks. BBB scores improved weeks 5–10 but remained below the control group. Stretched animals had significant deficits in knee passive ROM starting at week 4 and for the duration of the study. Kinematic assessment showed decreased joint excursion during stepping that partially recovered beginning at week 5. Conclusion Stretch-based therapy significantly impaired functional recovery in adult rats with a moderate contusive SCI at T10. The negative impact on function was greatest acutely, but persisted even after the stretching ceased at 8 weeks post-injury. PMID:25106555

  4. Distribution of bisphenol A into tissues of adult, neonatal, and fetal Sprague-Dawley rats

    SciTech Connect

    Doerge, Daniel R.; Twaddle, Nathan C.; Vanlandingham, Michelle; Brown, Ronald P.; Fisher, Jeffrey W.

    2011-09-15

    Bisphenol A (BPA) is an important industrial chemical used in the manufacture of polycarbonate plastic products and epoxy resin-based food can liners. The presence of BPA metabolites in urine of > 90% of Americans aged 6-60 suggests ubiquitous and frequent exposure in the range of 0.02-0.2 {mu}g/kg bw/d (25th-95th percentiles). The current study used LC/MS/MS to measure placental transfer and concentrations of aglycone (receptor-active) and conjugated (inactive) BPA in tissues from Sprague-Dawley rats administered deuterated BPA (100 {mu}g/kg bw) by oral and IV routes. In adult female rat tissues, the tissue/serum concentration ratios for aglycone BPA ranged from 0.7 in liver to 5 in adipose tissue, reflecting differences in tissue perfusion, composition, and metabolic capacity. Following IV administration to dams, placental transfer was observed for aglycone BPA into fetuses at several gestational days (GD), with fetal/maternal serum ratios of 2.7 at GD 12, 1.2 at GD 16, and 0.4 at GD 20; the corresponding ratios for conjugated BPA were 0.43, 0.65, and 3.7. These ratios were within the ranges observed in adult tissues and were not indicative of preferential accumulation of aglycone BPA or hydrolysis of conjugates in fetal tissue in vivo. Concentrations of aglycone BPA in GD 20 fetal brain were higher than in liver or serum. Oral administration of the same dose did not produce measurable levels of aglycone BPA in fetal tissues. Amniotic fluid consistently contained levels of BPA at or below those in maternal serum. Concentrations of aglycone BPA in tissues of neonatal rats decreased with age in a manner consistent with the corresponding circulating levels. Phase II metabolism of BPA increased with fetal age such that near-term fetus was similar to early post-natal rats. These results show that concentrations of aglycone BPA in fetal tissues are similar to those in other maternal and neonatal tissues and that maternal Phase II metabolism, especially following oral

  5. Influence of Panax ginseng on the offspring of adult rats exposed to prenatal stress

    PubMed Central

    KIM, YOUNG OCK; LEE, HWA-YOUNG; WON, HANSOL; NAH, SEONG-SU; LEE, HWA-YOUNG; KIM, HYUNG-KI; KWON, JUN-TACK; KIM, HAK-JAE

    2015-01-01

    The exposure of pregnant females to stress during a critical period of fetal brain development is an environmental risk factor for the development of schizophrenia in adult offspring. Schizophrenia is a group of common mental disorders of unclear origin, affecting approximately 1% of the global population, showing a generally young age at onset. In the present study, a repeated variable stress paradigm was applied to pregnant rats during the final week of gestation. The effects of an extract of Panax ginseng C.A. Meyer (PG) on rats exposed to prenatal stress (PNS) were investigated in terms of behavioral activity and protein expression analyses. In the behavioral tests, grooming behavior in a social interaction test, line-crossing behavior in an open-field test and swimming activity in a forced-swim test were decreased in the rats exposed to PNS compared with the non-stressed offspring; the changes in behavioral activity were reversed upon oral treatment with PG (300 mg/kg). Subsequently, western blot analysis and immunohistochemical analyses of the prefrontal cortex and hippocampus revealed that the downregulation of several neurodevelopmental genes which occurred following exposure to PNS was reversed upon treatment with PG. The current findings demonstrate that the downregulation of several genes following exposure to PNS may affect subsequent behavioral changes, and that these phenomena are reversed following treatment with PG during pregnancy. Our results suggest that oral treatment with PG reduces the incidence of psychiatric disorders, such as schizophrenia. PMID:25394395

  6. Prenatal testosterone supplementation alters puberty onset, aggressive behavior, and partner preference in adult male rats.

    PubMed

    Dela Cruz, Cynthia; Pereira, Oduvaldo C M

    2012-03-01

    The objective of this study was to investigate whether prenatal exposure to testosterone (T) could change the body weight (BW), anogenital distance (AGD), anogenital distance index (AGDI), puberty onset, social behavior, fertility, sexual behavior, sexual preference, and T level of male rats in adulthood. To test this hypothesis, pregnant rats received either 1 mg/animal of T propionate diluted in 0.1 ml peanut oil or 0.1 ml peanut oil, as control, on the 17th, 18th and 19th gestational days. No alterations in BW, AGD, AGDI, fertility, and sexual behavior were observed (p > 0.05). Delayed onset of puberty (p < 0.0001), increased aggressive behavior (p > 0.05), altered pattern of sexual preference (p < 0.05), and reduced T plasma level (p < 0.05) were observed for adult male rats exposed prenatally to T. In conclusion, the results showed that prenatal exposure to T was able to alter important aspects of sexual and social behavior although these animals were efficient at producing descendants. In this sense more studies should be carried to evaluated the real impact of this hormonal alteration on critical period of sexual differentiation on humans, because pregnant women exposed to hyperandrogenemia and then potentially exposing their unborn children to elevated androgen levels in the uterus can undergo alteration of normal levels of T during the sexual differentiation period, and, as a consequence, affect the reproductive and behavior patterns of their children in adulthood.

  7. Effects of different exercise protocols on ethanol-induced spatial memory impairment in adult male rats.

    PubMed

    Hashemi Nosrat Abadi, T; Vaghef, L; Babri, S; Mahmood-Alilo, M; Beirami, M

    2013-06-01

    Chronic ethanol consumption is often accompanied by numerous cognitive deficits and may lead to long-lasting impairments in spatial learning and memory. The aim of the present study was to evaluate the therapeutic potential of regular treadmill exercise on hippocampal-dependent memory in ethanol-treated rats. Spatial memory was tested in a Morris Water Maze task. Adult male Wistar rats were exposed to ethanol (4 g/kg, 20% v/v for 4 weeks) and effects of three exercise protocols (pre-ethanol, post-ethanol and pre-to-post-ethanol treatment) were examined. Results showed that ethanol exposure resulted in longer escape latencies during the acquisition phase of the Morris Water Maze task. Moreover, all three exercise protocols significantly decreased the latency to locate the hidden platform. During the probe trial, ethanol led to decreased time spent in the target quadrant. In contrast, performance on the probe trial was significantly better in the rats that had done the post- and pre-to-post-ethanol, but not pre-ethanol, exercises. These findings suggest that treadmill running can attenuate the adverse effects of chronic ethanol exposure on spatial memory, and may serve as a non-pharmacological alcohol abuse treatment.

  8. Daily patterns of ethanol drinking in peri-adolescent and adult alcohol-preferring (P) rats.

    PubMed

    Bell, Richard L; Rodd, Zachary A; Sable, Helen J K; Schultz, Jonathon A; Hsu, Cathleen C; Lumeng, Lawrence; Murphy, James M; McBride, William J

    2006-01-01

    Alcohol abuse among adolescents continues to be a major health problem for our society. Our laboratory has used the peri-adolescent alcohol-preferring, P, rat as an animal model of adolescent alcohol abuse. Even though peri-adolescent P rats consume more alcohol (g/kg/day) than their adult counterparts, it is uncertain whether their drinking is sufficiently aggregated to result in measurable blood ethanol concentrations (BECs). The objectives of this study were to examine daily alcohol drinking patterns of adolescent and adult, male and female P rats, and to determine whether alcohol drinking episodes were sufficiently aggregated to result in meaningful BECs. Male and female P rats were given 30 days of 24 h free-choice access to alcohol (15%, v/v) and water, with ad lib access to food, starting at the beginning of adolescence (PND 30) or adulthood (PND 90). Water and alcohol drinking patterns were monitored 22 h/day with a "lickometer" set-up. The results indicated that (a) peri-adolescent P rats consumed more water and total fluids than adult P rats, (b) female P rats consumed more water and total fluids than male P rats, (c) there were differences in alcohol, and water, licking patterns between peri-adolescent and adult and female and male P rats, (d) individual licking patterns revealed that alcohol was consumed in bouts often exceeding the amount required to self-administer 1 g/kg of alcohol, and (e) BECs at the end of the dark cycle, on the 30th day of alcohol access, averaged 50 mg%, with alcohol intakes during the last 1 to 2 h averaging 1.2 g/kg. Overall, these findings indicate that alcohol drinking patterns differ across the age and sex of P rats. This suggests that the effectiveness of treatments for reducing excessive alcohol intake may vary depending upon the age and/or sex of the subjects being tested.

  9. The effects of gonadectomy and binge-like ethanol exposure during adolescence on open field behaviour in adult male rats.

    PubMed

    Yan, Wensheng; Kang, Jie; Zhang, Guoliang; Li, Shuangcheng; Kang, Yunxiao; Wang, Lei; Shi, Geming

    2015-09-14

    Binge drinking ethanol exposure during adolescence can lead to long-term neurobehavioural damage. It is not known whether the pubertal surge in testosterone that occurs during adolescence might impact the neurobehavioural effects of early ethanol exposure in adult animals. We examined this hypothesis by performing sham or gonadectomy surgeries on Sprague-Dawley rats around postnatal day (P) 23. From P28-65,the rats were administered 3.0g/kg ethanol using a binge-like model of exposure. Dependent measurements included tests of open field behaviour, blood ethanol concentrations, and testosterone levels. As adults, significant decreases in open field activity were observed in the GX rats. The open field behaviour of the GX rats was restored after testosterone administration. Binge-like ethanol exposure altered most of the parameters of the open field behaviour, suggestive of alcohol-induced anxiety, but rats treated with alcohol in combination with gonadectomy showed less motor behaviour and grooming behaviour and an increase in immobility, suggesting ethanol-induced depression. These results indicated that testosterone is required for ethanol-induced behavioural changes and that testicular hormones are potent stimulators of ethanol-induced behaviours.

  10. Perinatal malnutrition programs sympathoadrenal and hypothalamic-pituitary-adrenal axis responsiveness to restraint stress in adult male rats.

    PubMed

    Lesage, J; Dufourny, L; Laborie, C; Bernet, F; Blondeau, B; Avril, I; Bréant, B; Dupouy, J P

    2002-02-01

    In humans, an altered control of cortisol secretion was reported in adult men born with a low birth weight making the hypothalamic-pituitary-adrenal (HPA) axis a possible primary target of early life programming. In rats, we have recently shown that maternal food restriction during late pregnancy induces both an intrauterine growth retardation and an overexposure of fetuses to maternal corticosterone, which disturb the development of the HPA axis in offspring. The first aim of this work was to investigate, in adult male rats, whether perinatal malnutrition has long-lasting effects on the HPA axis activity during both basal and stressful conditions. Moreover, as the HPA axis and sympathetic nervous system are both activated by stress, the second aim of this work was to investigate, in these rats, the adrenomedullary catecholaminergic system under basal and stressful conditions. This study was conducted on 4-month-old male rats malnourished during their perinatal life and on age-matched control animals. Under basal conditions, perinatal malnutrition reduced body weight and plasma corticosteroid-binding globulin (CBG) level but increased mineralocorticoid receptor (MR) gene expression in CA1 hippocampal area. After 30 min of restraint, perinatally malnourished (PM) rats showed increased plasma noradrenaline, adrenocorticotropin hormone (ACTH) and corticosterone concentrations similarly as controls, but calculated plasma-free corticosterone concentration was significantly higher and adrenaline level lower than controls. During the phase of recovery, PM rats showed a rapid return of plasma ACTH and corticosterone concentrations to baseline levels in comparison with controls. These data suggest that in PM rats, an elevation of basal concentrations of corticosterone, in face of reduced CBG and probably increased hippocampal MR lead to a much larger impact of corticosterone on target cells that mediate the negative-feedback mechanism on the activities of both the HPA axis

  11. Some histological effects of chronic administration of chloroquine on the medial geniculate body of adult wistar rat.

    PubMed

    Adjene, J O; Caxton-Martins, A E

    2006-06-01

    Some histological effects of chronic administration of chloroquine commonly used for prophylaxis or treatment of malaria. rheumatoid arthritis and lupus erythematosus on the medial geniculate body (MGB) of adult wistar rats was carefully studied. The rats of both sexes (n= 18), average weight of 184g were randomly assigned into treatment (n= 10) and control (n=7) groups. The rats in the treatment group received 2mg/kg body weight of chloroquine base dissolved in distilled water daily for fourteen days through the orogastric tube administration while the control rats received equal volume of distilled water daily through the same route. The rats were fed with rat pellets purchased from Topfeed Ltd. Sapele. Delta State. Nigeria and given water liberally and were then sacrificed on day fifteen of the experiment. The MGB were carefully dissected out and quickly fixed in 10% formal saline for routine histological study after H & E and thionin methods. The histological findings after H & E methods indicated that the treated sections of the MGB showed faintly reduced nuclei size, with the presence of many autophagic vacuoles and degenerative neurons when compared to the control sections. On the other hand. the thionin method indicated that the treated sections showed sparsely distributed neurons, which stain less intensely when compared with the control. The nissl substance in some of the neurons appeared degenerative while some hypertrophied with some vacuolations. These findings indicated that chronic administration of chloroquine has a deleterious effect on the neurons and nissl substance of the MGB. Chloroquine may probably have adverse effects on auditory sensibilities by its deleterious effects on the nerve cells and nissl substances of the MGB of the adult wistar rats. It is recommended that further studies aimed at corroborating these observations be carried out. PMID:17209307

  12. Altered dendritic arborization of amygdala neurons in young adult rats orally intubated with Clitorea ternatea aqueous root extract.

    PubMed

    Rai, Kiranmai S; Murthy, K Dilip; Rao, Muddanna S; Karanth, K Sudhakar

    2005-07-01

    Young adult (60 day old) Wistar rats of either sex were orally intubated with 50 mg/kg body weight and 100 mg/kg body weight of aqueous root extract of Clitoria ternatea (CTR) for 30 days, along with age-matched saline controls. These rats were then subjected to passive avoidance tests and the results from these studies showed a significant increase in passive avoidance learning and retention. Subsequent to the passive avoidance tests, these rats were killed by decapitation. The amygdala was processed for Golgi staining and the stained neurons were traced using a camera lucida and analysed. The results showed a significant increase in dendritic intersections, branching points and dendritic processes arising from the soma of amygdaloid neurons in CTR treated rats especially in the 100 mg/kg group of rats, compared with age-matched saline controls. This improved dendritic arborization of amygdaloid neurons correlates with the increased passive avoidance learning and memory in the CTR treated rats as reported earlier. The results suggest that Clitoria ternatea aqueous root extract enhances memory by increasing the functional growth of neurons of the amygdala. PMID:16161034

  13. Some factors influencing cadmium-manganese interaction in adult rats

    SciTech Connect

    Gruden, N.; Matausic, S. )

    1989-07-01

    Recent data show that even a low dose of cadmium (20 {mu}g/day/rat) significantly suppresses manganese transduodenal transport when administered during a three-day period. The inhibitory effect of cadmium upon manganese absorption is enhanced by concurrently administered iron-fortified milk diet. This suggests that the (synergistic) action of cadmium and iron upon manganese and the competition between these (three) ions in the intestine depend on their relative concentrations and affinity for the binding sites within the intestinal mucosa. For this reason the authors considered it worthwhile examining whether this inhibitory effect of cadmium would be affected by simultaneously administered manganese-fortified milk. Since the absorption of heavy metals and, at the same time, the demand for manganese is higher in the young than in the old animals, they also studied how this interaction depends upon the animals' age and sex and whether it is the same in the whole small intestine.

  14. Prenatal caffeine exposure induces a poor quality of articular cartilage in male adult offspring rats via cholesterol accumulation in cartilage

    PubMed Central

    Luo, Hanwen; Li, Jing; Cao, Hong; Tan, Yang; Magdalou, Jacques; Chen, Liaobin; Wang, Hui

    2015-01-01

    Epidemiological investigations indicate that osteoarthritis is associated with intrauterine growth retardation (IUGR) and abnormal cholesterol metabolism. Our previous studies showed that prenatal caffeine exposure (PCE) induced chondrogenesis retardation in IUGR offspring rats. The current study sought to investigate the effects of PCE on male IUGR offspring rats’ articular cartilage, and the mechanisms associated with abnormal cholesterol metabolism. Based on the results from both male fetal and adult fed a high-fat diet (HFD) studies of rats that experienced PCE (120 mg/kg.d), the results showed a poor quality of articular cartilage and cholesterol accumulation in the adult PCE group. Meanwhile, the serum total cholesterol and low-density lipoprotein-cholesterol concentrations were increased in adult PCE offspring. We also observed lower expression of insulin-like growth factor1 (IGF1) and impaired cholesterol efflux in adult articular cartilage. Furthermore, the expression of cartilage functional genes, components of the IGF1 signaling pathway and cholesterol efflux pathway related genes were decreased in PCE fetal cartilage. In conclusion, PCE induced a poor quality of articular cartilage in male adult offspring fed a HFD. This finding was shown to be due to cholesterol accumulation in the cartilage, which may have resulted from intrauterine reduced activity of the IGF1 signaling pathway. PMID:26639318

  15. Neocortical neurodegeneration in young adult Wistar rats prenatally exposed to ethanol.

    PubMed

    Fakoya, Francis Adelade; Caxton-Martins, Ezekiel Ademola

    2006-01-01

    This study was aimed to determine the persistence of neurodegeneration in the cerebral cortex of adult Wistar rats following prenatal ethanol exposure. Timed pregnant rats maintained on standard mouse chow (Ladokun Feeds, Ibadan, Nigeria) and water ad libitum were used for the study. The rats were divided randomly into groups A and B (n-6) and C (n = 4). Group A received a daily ethanol dose of 5.8 g/Kg body weight/day, on the 9th, 10th, 11th, and 12th days of gestation by intragastric intubation, at 16.00 h (PEE) group B was pair-fed with the ethanol dams on isocaloric solution of sucrose for the same duration (PF), while group C received standard chow (C) and water ad libitum. At birth, the pups were weighed and weaned at 30 days of age. Wet brain weights of adult offsprings were determined at 42 days of age. Following whole body perfusion-fixation after anaesthesia, specimens of the neocortex were processed routinely for paraffin embedding and sections of 6 mum thickness stained for neurohistology from each group. Another set of specimens was cryosectioned at -23 degrees C and evaluated for apoptosis by the TUNEL method. The study showed a significantly sustained 44% reduction in brain weight. Neurodegeneration was evident in the layer V, consisting of mostly pyknotic pyramidal neurons, with broken dendrites, collapsed cell bodies, obliterated nuclei and nucleoli. There was a 55% decrease in the normal pyramidal neuron cell pack density. The negative TUNEL signals in both groups suggest that apoptosis may play no role in the mechanism of action occurring at this age of the animals. These sustained changes may underlie the neurobehavioural deficits that have been variously reported. PMID:16503114

  16. Effect of methamphetamine exposure and cross-fostering on cognitive function in adult male rats.

    PubMed

    Hrubá, Lenka; Schutová, Barbora; Pometlová, Marie; Rokyta, Richard; Slamberová, Romana

    2010-03-17

    The aim of our study was to examine the effect of prenatal methamphetamine (MA) exposure and cross-fostering on cognitive functions of adult male rats tested in Morris water maze (MWM). Rat mothers were exposed daily to injection of MA (5mg/kg) or saline for 9 weeks: prior to impregnation, throughout gestation and lactation periods. Females without any injections were used as an absolute control. On postnatal day 1, pups were cross-fostered so that each mother raised 4 pups of her own and 8 pups from the mothers with the other two treatments. Four types of tests were used: (1) Place navigation test (Learning), (2) Probe test (Probe), (3) Retention memory test (Memory) and (4) Visible platform task. Our results demonstrate that the prenatal exposure to MA does not impact learning and memory, while postnatal exposure to MA shows impairments in cognition. In the test of learning, all animals fostered to MA-treated dams had longer latencies, bigger search error and used lower spatial strategies than the animals fostered to control or saline-treated mother, regardless of prenatal exposure. Regardless of postnatal exposure, the animals prenatally exposed to saline swam faster in all the tests than the animals prenatally exposed to MA and controls, respectively. This study indicates that postnatal but not prenatal exposure to MA affects learning in adult male rats. However, it is still not clear whether these impairments are due to a direct effect of MA on neuronal structure or due to an indirect effect of MA mediated by impaired maternal care.

  17. Subculture of proliferating adult rat hepatocytes in medium supplemented with nicotinamide and EGF.

    PubMed

    Mitaka, T; Kojima, T; Mizuguchi, T; Mochizuki, Y

    1996-09-01

    To establish parenchymal hepatocyte cell lines, we tried to subculture the primary hepatocytes isolated from adult rats. The hepatocytes were cultured in serum-free modified Dulbecco's modified Eagle's medium supplemented with 10 mM nicotinamide and 10 ng/ml epidermal growth factor. When 6 x 10(5) cells were plated on 35-mm dishes coated with rat tail collagen, the cells proliferated and reached confluence at Day 6 to Day 8. The first subculture was carried out at Day 8 using 0.005% collagenase and gentle pipettings. Most cells were recovered and plated on the new dishes coated with the collagen (first passage). The attached cells could proliferate and reached near confluence when the cells occupied more than two-thirds of the dish surface. About a week after the first subculture, the second one was conducted. Although the number of the recovered cells was smaller than at the first passage, the cells could attach and proliferate to a certain extent. Thereafter, they were maintained for more than 2 mo, but they never overgrew. Albumin secretion into the culture medium was confirmed in the subcultured cells. Ultrastructurally, these subcultured cells possessed hepatic characteristics such as peroxisomes with a crystalline nucleiod and bile-canaliculus structures. When 10% fetal bovine serum and ascorbic acid 2-phosphate were added to the cells of the second passage, they began to proliferate very slowly. These proliferating cells were mainly mononucleate and had a small cytoplasm. In addition, some of them could differentitate into typical mature hepatocytes by forming a three-dimensional structure interacting with nonparenchymal cells. In this experiment, we showed the successful subculturing of parenchymal hepatocytes isolated from adult rats and provided evidence that the subcultured cells still have the potential to proliferate and to differentiate.

  18. Preterm birth and unintentional injuries: risks to children, adolescents and young adults show no consistent pattern

    PubMed Central

    Calling, Susanna; Palmér, Karolina; Jönsson, Lena; Sundquist, Jan; Winkleby, Marilyn; Sundquist, Kristina

    2012-01-01

    Aim Preterm birth is associated with a number of physical and mental health issues. The aim of this study was to find out if there was also any association between individuals born preterm in Sweden between 1984 and 2006 and the risk of unintentional injuries during childhood, adolescence and young adulthood. Methods The study followed 2,297,134 individuals, including 5.9% born preterm, from 1985 to 2007 for unintentional injuries leading to hospitalisation or death (n=244,021). The males and females were divided into four age groups: 1–5 years, 6–12 years, 13–18 years and 19–23 years. Hazard ratios were calculated for falls, transport injuries and other injuries. Results After adjusting for a comprehensive set of covariates, some of the preterm subgroups demonstrated slightly increased risks of unintentional injuries, while others showed slightly decreased risks. However, most of the estimates were borderline or non-significant in both males and females. In addition, the absolute risk differences between individuals born preterm and full term were small. Conclusion Despite the association between preterm birth and a variety of physical and mental health consequences, this study shows that there is no consistent risk pattern between preterm birth and unintentional injuries in childhood, adolescence and young adulthood. PMID:23181809

  19. The effects of acute alcohol on motor impairments in adolescent, adult, and aged rats.

    PubMed

    Ornelas, Laura C; Novier, Adelle; Van Skike, Candice E; Diaz-Granados, Jaime L; Matthews, Douglas B

    2015-03-01

    Acute alcohol exposure has been shown to produce differential motor impairments between aged and adult rats and between adolescent and adult rats. However, the effects of acute alcohol exposure among adolescent, adult, and aged rats have yet to be systematically investigated within the same project using a dose-dependent analysis. We sought to determine the age- and dose-dependent effects of acute alcohol exposure on gross and coordinated motor performance across the rodent lifespan. Adolescent (PD 30), adult (PD 70), and aged (approximately 18 months) male Sprague-Dawley rats were tested on 3 separate motor tasks: aerial righting reflex (ARR), accelerating rotarod (RR), and loss of righting reflex (LORR). In a separate group of animals, blood ethanol concentrations (BEC) were determined at multiple time points following a 3.0 g/kg ethanol injection. Behavioral tests were conducted with a Latin square repeated-measures design in which all animals received the following doses: 1.0 g/kg or 2.0 g/kg alcohol or saline over 3 separate sessions via intraperitoneal (i.p.) injection. During testing, motor impairments were assessed on the RR 10 min post-injection and on ARR 20 min post-injection. Aged animals spent significantly less time on the RR when administered 1.0 g/kg alcohol compared to adult rats. In addition, motor performance impairments significantly increased with age after 2.0 g/kg alcohol administration. On the ARR test, aged rats were more sensitive to the effects of 1.0 g/kg and 2.0 g/kg alcohol compared to adolescents and adults. Seven days after the last testing session, animals were given 3.0 g/kg alcohol and LORR was examined. During LORR, aged animals slept longer compared to adult and adolescent rats. This effect cannot be explained solely by BEC levels in aged rats. The present study suggests that acute alcohol exposure produces greater motor impairments in older rats when compared to adolescent and adult rats and begins to establish a

  20. Testosterone differentially alters cocaine-induced ambulatory and rearing behavioral responses in adult and adolescent rats

    PubMed Central

    Minerly, AnaChristina E.; Wu, Hui Bing K.; Weierstall, Karen M.; Niyomchai, Tipyamol; Kemen, Lynne; Jenab, Shirzad; Quinones-Jenab, Vanya

    2016-01-01

    Little is known about the physiological and behavioral effects of testosterone when co-administered with cocaine during adolescence. The present study aimed to determine whether exogenous testosterone administration differentially alters psychomotor responses to cocaine in adolescent and adult male rats. To this end, intact adolescent (30-days-old) and adult (60-day-old) male Fisher rats were pretreated with vehicle (sesame oil) or testosterone (5 or 10 mg/kg) 45 minutes prior to saline or cocaine (20 mg/kg) administration. Behavioral responses were monitored 1 hour after drug treatment, and serum testosterone levels were determined. Serum testosterone levels were affected by age: saline- and cocaine-treated adults in the vehicle groups had higher serum testosterone levels than adolescents rats, but after co-administration of testosterone the adolescent rats had higher serum testosterone levels than the adults. Pretreatment with testosterone affected baseline activity in adolescent rats: 5 mg/kg of testosterone increased both rearing and ambulatory behaviors in saline-treated adolescent rats. After normalizing data to % saline, an interaction between hormone administration and cocaine-induced behavioral responses was observed; 5 mg/kg of testosterone decreased both ambulatory and rearing behaviors among adolescents whereas 10 mg/kg of testosterone decreased only rearing behaviors. Testosterone pretreatment did not alter cocaine-induced behavioral responses in adult rats. These findings suggest that adolescents are more sensitive than adults to an interaction between testosterone and cocaine, and, indirectly, suggest that androgen abuse may lessen cocaine-induced behavioral responses in younger cocaine users. PMID:19822170

  1. Neonatal handling causes impulsive behavior and decreased pharmacological response to methylphenidate in male adult wistar rats.

    PubMed

    Lazzaretti, Camilla; Kincheski, Grasielle Clotildes; Pandolfo, Pablo; Krolow, Rachel; Toniazzo, Ana Paula; Arcego, Danusa Mar; Couto-Pereira, Natividade de Sá; Zeidán-Chuliá, Fares; Galvalisi, Martin; Costa, Gustavo; Scorza, Cecilia; Souza, Tadeu Mello E; Dalmaz, Carla

    2016-03-01

    Neonatal handling has an impact on adult behavior of experimental animals and is associated with rapid and increased palatable food ingestion, impaired behavioral flexibility, and fearless behavior to novel environments. These symptoms are characteristic features of impulsive trait, being controlled by the medial prefrontal cortex (mPFC). Impulsive behavior is a key component of many psychiatric disorders such as attention deficit hyperactivity disorder (ADHD), manic behavior, and schizophrenia. Others have reported a methylphenidate (MPH)-induced enhancement of mPFC functioning and improvements in behavioral core symptoms of ADHD patients. The aims of the present study were: (i) to find in vivo evidence for an association between neonatal handling and the development of impulsive behavior in adult Wistar rats and (ii) to test whether neonatal handling could have an impact on monoamine levels in the mPFC and the pharmacological response to MPH in vivo. Therefore, experimental animals (litters) were classified as: "non-handled" and "handled" (10[Formula: see text]min/day, postnatal days 1-10). After puberty, they were exposed to either a larger and delayed or smaller and immediate reward (tolerance to delay of reward task). Acute MPH (3[Formula: see text]mg/Kg. i.p.) was used to suppress and/or regulate impulsive behavior. Our results show that only neonatally handled male adult Wistar rats exhibit impulsive behavior with no significant differences in monoamine levels in the medial prefrontal cortex, together with a decreased response to MPH. On this basis, we postulate that early life interventions may have long-term effects on inhibitory control mechanisms and affect the later response to pharmacological agents during adulthood.

  2. Adult partner preference and sexual behavior of male rats affected by perinatal endocrine manipulations.

    PubMed

    Brand, T; Kroonen, J; Mos, J; Slob, A K

    1991-09-01

    Intact adult male rats, in which aromatization of testosterone to estradiol was prevented pre- and/or neonatally by ATD (1,4,6-androstatriene-3,17-dione), were repeatedly tested for partner preference behavior (choice: estrous female vs active male). In consecutive tests increasing preference scores for the female were found. Neonatal ATD males showed significantly lower preference scores for an estrous female than controls or prenatal ATD males. Prenatal ATD caused preference scores only slightly lower than those of controls. Ejaculation frequencies were markedly reduced or even absent in neonatal ATD males. Prenatal ATD treatment only had no or a moderately lowering effect on ejaculation frequency. Lordosis behavior of adult intact males was more facilitated following neonatal ATD treatment than following prenatal ATD treatment. In a number of tests the serotonergic drug 8-OH-DPAT was injected prior to testing for sexual partner preference and copulatory behavior. DPAT significantly increased preference for an estrous female in all groups of males when interaction was possible, but had no effect when sexual interaction was prevented by wire mesh. DPAT was able to increase the number of ejaculators in nonejaculating groups (i.e., perinatally ATD-treated males). "Premature ejaculations," i.e., ejaculations with the first intromission, were frequently observed with DPAT treatment in all groups of males. In conclusion, the availability of neonatal estrogen (derived from testosterone) organizes, at least partially, the preference for an estrous female normally shown by adult male rats. The lack of neonatal estrogen causes males to be less masculinized, both in partner preference behavior and ejaculatory behavior, and less defeminized in lordosis behavior.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. 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.

  4. Extensor motoneurone properties are altered immediately before and during fictive locomotion in the adult decerebrate rat

    PubMed Central

    MacDonell, C W; Power, K E; Chopek, J W; Gardiner, K R; Gardiner, P F

    2015-01-01

    Key points This is the first report, in adult decerebrate rats, to examine intracellular hindlimb motoneurone properties during quiescence, fictive locomotion and a tonic period immediately before fictive locomotion that is characterized by increased peripheral nerve activity. It is shown for the first time during fictive locomotion that motoneurones become more responsive in the tonic period, suggesting that the motoneurone pool becomes primed before patterned motor output commences. Spike frequency adaptation exists in quiescence and during fictive locomotion during constant excitation with injected current but not during centrally driven fictive locomotion. Motoneurones within the extensor motor pool show changes in excitability even when they are not directly involved in locomotion. The data show increased responsiveness of motoneurones during locomotion via a lowered threshold for spike initiation and decreased rheobase. Abstract This study examined motoneurone properties during fictive locomotion in the adult rat for the first time. Fictive locomotion was induced via electrical stimulation of the mesencephalic locomotor region in decerebrate adult rats under neuromuscular blockade to compare basic and rhythmic motoneurone properties in antidromically identified extensor motoneurones during: (1) quiescence, before and after fictive locomotion; (2) the ‘tonic’ period immediately preceding locomotor-like activity, whereby the amplitude of peripheral flexor (peroneal) and extensor (tibial) nerves are increased but alternation has not yet occurred; and (3) locomotor-like episodes. Locomotion was identified by alternating flexor–extensor nerve activity, where the motoneurone either produced membrane oscillations consistent with a locomotor drive potential (LDP) or did not display membrane oscillation during alternating nerve activity. Cells producing LDPs were referred to as such, while those that did not were referred to as ‘idle’ motoneurones. LDP and

  5. Role of Periductal and Ductular Epithelial Cells of the Adult Rat Pancreas in Pancreatic Hepatocyte Lineage

    PubMed Central

    Rao, M. Sambasiva; Dwivedi, Rama S.; Yeldandi, Anjana V.; Subbarao, V.; Tan, Xiaodi; Usman, Mohammed I.; Thangada, Shobha; Nemali, Mohan R.; Kumar, Sujata; Scarpelli, Dante G.; Reddy, Janardan K.

    1989-01-01

    Development of pancreatic hepatocytes in adult rats maintained on copper dificient diet containing 0.6% trien (CuDT) has been reported recently. To elucidate the histogenesis of hepatocytes a sequential study was undertaken using morphologic, histochemical, immunochemical, in situ hybridization, and Northern blot analysis. Male F-344 rats weighing 80 to 90 g were fed CuDT for 8 weeks and returned to normal rat chow. Beginning from 4 weeks of copper depletion, there was a progressive loss of acinar cells and by 8 weeks more than 90% of the acinar tissue was lost. During this period, there was an increase in the number of adipocytes in the interstitium, and in the number of interstitial and ductular cells. Morphologic observations were confirmed by immunoblot and Northern blot analysis, in which the amount of pancreatic proteins and their mRNAs decreased between 5 and 8 weeks. During this period, a progressive increase in the level of albumin mRNA was observed. In situ hybridization, performed at 7 weeks of copper deficiency, showed localization of albumin mRNA over interstitial and ductular cells. Pancreatic hepatocytes were identified immediately after the rats were returned to a normal diet and gradually increased in number. The hepatocytes occupied almost 60% of the pancreatic volume by 8 weeks. During the early recovery phase, hepatocytes were identified in ductules as well as in the interstitium. Based on these studies, it is concluded that both the ductular cells and interstitial cells, which resemble oval cells of liver, are capable of transforming into pancreatic hepatocytes and these cells may be considered stem-cell equivalent. ImagesFigure 9Figure 10Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 11Figure 12Figure 13Figure 14Figure 15Figure 16 PMID:2470253

  6. Persistent neocortical astrogliosis in adult wistar rats following prenatal ethanol exposure.

    PubMed

    Fakoya, Francis Adelade

    2005-06-01

    Timed pregnant wistar rats were divided randomly into groups A and B (n=6) each and C (n=4). Group A received a daily ethanol dose of 5.8 g/kg body weight per day, at 16.00 h on days 9-12th of gestation by intragastric intubations. Group B was pair-fed along with the treated rats and received an isocaloric solution of sucrose to substitute for the ethanol in the experimental group, for the same duration, while group C received standard chow and water ad libitum. The adult offsprings at 42 days of age, (n=10) from each group were sacrificed by whole body perfusion-fixation, after anaesthesia by an overdose of pentothal intraperitoneally. Specimens of neocortical samples were processed routinely for paraffin embedding and sections of 6 microm thickness stained for neurohistology. Another set of specimens was cryosectioned at -23 degrees C after cryoprotection in 30% sucrose/PBS and evaluated for GFAP immunohistochemistry. The study showed a distortion of the microanatomy of the neocortex in the treatment group A, particularly of layer V pyramidal neurons, which revealed mostly pyknotic pyramidal neurons with broken dendrites, collapsed cell bodies, obliterated nuclei and nucleoli. No differences were found between the brains from rats in groups B and C. There were widespread focal areas of reactive astrogliosis, more prominent within the layer V. Astrocytes demonstrated highly stained GFAP-positive immunoreactivity with heavy fibrillary processes in the neocortex of group A offsprings compared to the controls. The sub-pial regions were, however, sparse. In conclusion, this study confirms the hypothesis that microanatomical and microchemical changes following prenatal ethanol exposure persist into adulthood in rats. PMID:15862187

  7. Potent spinal parenchymal AAV9-mediated gene delivery by subpial injection in adult rats and pigs

    PubMed Central

    Miyanohara, Atsushi; Kamizato, Kota; Juhas, Stefan; Juhasova, Jana; Navarro, Michael; Marsala, Silvia; Lukacova, Nada; Hruska-Plochan, Marian; Curtis, Erik; Gabel, Brandon; Ciacci, Joseph; Ahrens, Eric T; Kaspar, Brian K; Cleveland, Don; Marsala, Martin

    2016-01-01

    Effective in vivo use of adeno-associated virus (AAV)-based vectors to achieve gene-specific silencing or upregulation in the central nervous system has been limited by the inability to provide more than limited deep parenchymal expression in adult animals using delivery routes with the most clinical relevance (intravenous or intrathecal). Here, we demonstrate that the spinal pia membrane represents the primary barrier limiting effective AAV9 penetration into the spinal parenchyma after intrathecal AAV9 delivery. We develop a novel subpial AAV9 delivery technique and AAV9-dextran formulation. We use these in adult rats and pigs to show (i) potent spinal parenchymal transgene expression in white and gray matter including neurons, glial and endothelial cells after single bolus subpial AAV9 delivery; (ii) delivery to almost all apparent descending motor axons throughout the length of the spinal cord after cervical or thoracic subpial AAV9 injection; (iii) potent retrograde transgene expression in brain motor centers (motor cortex and brain stem); and (iv) the relative safety of this approach by defining normal neurological function for up to 6 months after AAV9 delivery. Thus, subpial delivery of AAV9 enables gene-based therapies with a wide range of potential experimental and clinical utilizations in adult animals and human patients. PMID:27462649

  8. Cyclophosphamide-induced immunosuppression protects cardiac noradrenergic nerve terminals from damage by Trypanosoma cruzi infection in adult rats.

    PubMed

    Guerra, L B; Andrade, L O; Galvão, L M; Macedo, A M; Machado, C R

    2001-01-01

    Trypanosoma cruzi-infected juvenile rats develop severe cardiac sympathetic denervation in parallel with acute myocarditis. This aspect has not been studied in adult rats, thought to be resistant to this infection. The mechanism involved in T. cruzi-induced neuronal damage remains to be completely elucidated. In juvenile rats, the mortality during the acute phase depends on T. cruzi populations, ranging from 30% to 100%. Therefore, studies of mechanisms through hazardous procedures such as immunosuppression are restricted. The current paper shows that adult rats infected with T. cruzi (Y strain) develop severe acute myocarditis and cardiac sympathetic denervation, despite null mortality and virtual absence of patent parasitaemia followed by negative haemoculture. Recovery from the myocarditis and denervation occurred but PCR studies showed persistence of parasite DNA at least until day 111 post inoculation. Immunosuppression by cyclophosphamide treatment increased the parasitaemia, prevented the acute myocarditis and the sympathetic denervation without significant alteration of the myocardial parasitism. These results argue against a direct role for parasite-derived products and implicate the inflammatory cells in the denervation process. As previous studies in juvenile animals have discarded an essential role for radiosensitive cells, the macrophages remain as the possible effectors for the T. cruzi-induced neuronal damage.

  9. A quantitative study on feedback control of LH by testosterone in young adult and old male rats.

    PubMed

    Pirke, K M; Geiss, M; Sintermann, R

    1978-12-01

    The hypothalamic pituitary gonadal axis was studied in young adult (3 month old) and old (24 to 27 month old) male Wistar rats. Plasma testosterone decreased significantly in old animals (x: 262 hg/100 ml (n = 35); versus x: 110 ng/100 ml (n =30). The fall in LH was less pronounced but still significant (54.5 ng LH-RP-1/ml in young versus 39.5 ng/ml in old rats). Groups of 6 to 8 animals of both ages were castrated and implanted with silastic capsules continuously releasing testosterone. The length of the capsules was directly proportional to the plasma testosterone levels achieved (range between 63 and 350 ng/100 ml). After one week young castrated rats not substituted with testosterone showed LH values three times higher (x: 351 ng/ml) than old rats treated in the same way (x = 126 ng/ml). LH values in the animals substituted with testosterone indicate that the sensitivity of the negative testosterone-LH feedback is greatly increased in old rats. Testosterone can be depressed to 60 ng/100 ml before an increase in LH occurs. In young rats no increase in LH was observed when testosterone values were higher than 170 ng/100 ml. In the range between 170 and 100 ng/100 ml about half of the young animals reacted with increased LH secretion, while an increase was observed in all young animals when testosterone dropped below 100 ng/100 ml.

  10. Vitamin D deficiency during various stages of pregnancy in the rat; its impact on development and behaviour in adult offspring.

    PubMed

    O'Loan, Jonathan; Eyles, Darryl W; Kesby, James; Ko, Pauline; McGrath, John J; Burne, Thomas H J

    2007-04-01

    Developmental vitamin D (DVD) deficiency alters brain development and behaviour in the rat. The aim of this study was to vary levels of vitamin D deficiency during gestation and examine the effects on developmental milestones and behaviour in adult offspring. By manipulating the withdrawal and reintroduction of vitamin D in the diet of female Sprague-Dawley rats, their offspring were subjected to four different prenatal vitamin D conditions: (a) control (normal vitamin D throughout gestation); (b) early-DVD deficiency; (c) late-DVD deficiency; and (d) full-DVD deficiency. We show that the standard measure for vitamin D status, 25(OH)D(3), can be significantly manipulated within 7 days by dietary intervention. We also show that levels of the active form of this vitamin, 1,25(OH)(2)D(3), replete within the same time frame as 25(OH)D(3) but are slower to deplete. Developmental milestones remained normal across all four dietary groups. Concerning the adult behavioural phenotype, both full- and late-DVD deficiency were associated with MK-801-induced hyperlocomotion. Overall, these data suggest that vitamin D deficiency restricted to late gestation only is sufficient to disrupt adult brain functioning in the rat. These findings suggest there may be a therapeutic window for maternal dietary intervention in the DVD model of psychosis. PMID:17276604

  11. Histologic and histomorphometric changes of testis following oral exposure to methyl tertiary-butyl ether in adult rat.

    PubMed

    Gholami, S; Ansari-Lari, M; Khalili, L

    2015-01-01

    Methyl tertiary-butyl ether (MTBE) is used to reduce carbon monoxide and ozone in urban air and to boost fuel octane. There is a lack of knowledge in the literature about the histomorphometric changes of the testis following exposure to MTBE. Therefore, this experimental study was performed to determine the effect of oral exposure to MTBE on histologic and histomorphometric changes of testis in adult rat. A total of 25 adult male Sprague-Dawley rats were randomly divided into five equal experimental groups: control, almond oil and three treatment groups which received 400, 800 and 1600 mg/kg/day MTBE in almond oil by gavages for 30 consecutive days. Histomorphometric analysis showed no significant difference in absolute and relative testis weight, connective tissue thickness, germinal epithelium height, tunica albuginea thickness and Sertoli cell numbers between experimental groups (P>0.05). However, trend analysis showed that the seminiferous tubule diameter increased and interstitial cell numbers as well as spermatocyte and spermatid cell numbers decreased significantly in MTBE treated groups (P<0.05). It may be concluded that MTBE could exert adverse effects on spermatogenic cells in adult rat. Whether the observed changes in the present study are due to the direct effect of MTBE via passing blood-testis barrier or its indirect effect through another mechanism should be elucidated in future studies. PMID:27175191

  12. Blood-brain barrier permeability is increased after acute adult stroke but not neonatal stroke in the rat.

    PubMed

    Fernández-López, David; Faustino, Joel; Daneman, Richard; Zhou, Lu; Lee, Sarah Y; Derugin, Nikita; Wendland, Michael F; Vexler, Zinaida S

    2012-07-11

    The immaturity of the CNS at birth greatly affects injury after stroke but the contribution of the blood-brain barrier (BBB) to the differential response to stroke in adults and neonates is poorly understood. We asked whether the structure and function of the BBB is disrupted differently in neonatal and adult rats by transient middle cerebral artery occlusion. In adult rats, albumin leakage into injured regions was markedly increased during 2-24 h reperfusion but leakage remained low in the neonates. Functional assays employing intravascular tracers in the neonates showed that BBB permeability to both large (70 kDa dextran) and small (3 kDa dextran), gadolinium (III)-diethyltriaminepentaacetic acid tracers remained largely undisturbed 24 h after reperfusion. The profoundly different functional integrity of the BBB was associated with the largely nonoverlapping patterns of regulated genes in endothelial cells purified from injured and uninjured adult and neonatal brain at 24 h (endothelial transcriptome, 31,042 total probe sets). Within significantly regulated 1266 probe sets in injured adults and 361 probe sets in neonates, changes in the gene expression of the basal lamina components, adhesion molecules, the tight junction protein occludin, and matrix metalloproteinase-9 were among the key differences. The protein expression of collagen-IV, laminin, claudin-5, occludin, and zonula occludens protein 1 was also better preserved in neonatal rats. Neutrophil infiltration remained low in acutely injured neonates but neutralization of cytokine-induced neutrophil chemoattractant-1 in the systemic circulation enhanced neutrophil infiltration, BBB permeability, and injury. The markedly more integrant BBB in neonatal brain than in adult brain after acute stroke may have major implications for the treatment of neonatal stroke. PMID:22787045

  13. Quantitative proteomics of rat livers shows that unrestricted feeding is stressful for proteostasis with implications on life span

    PubMed Central

    Pinto, Galit; Quadroni, Manfredo; Shtaif, Biana; Goloubinoff, Pierre

    2016-01-01

    Studies in young mammals on the molecular effects of food restriction leading to prolong adult life are scares. Here, we used high-throughput quantitative proteomic analysis of whole rat livers to address the molecular basis for growth arrest and the apparent life-prolonging phenotype of the food restriction regimen. Over 1800 common proteins were significantly quantified in livers of ad libitum, restriction- and re-fed rats, which summed up into 92% of the total protein mass of the cells. Compared to restriction, ad libitum cells contained significantly less mitochondrial catabolic enzymes and more cytosolic and ER HSP90 and HSP70 chaperones, which are hallmarks of heat- and chemically-stressed tissues. Following re-feeding, levels of HSPs nearly reached ad libitum levels. The quantitative and qualitative protein values indicated that the restriction regimen was a least stressful condition that used minimal amounts of HSP-chaperones to maintain optimal protein homeostasis and sustain optimal life span. In contrast, the elevated levels of HSP-chaperones in ad libitum tissues were characteristic of a chronic stress, which in the long term could lead to early aging and shorter life span. PMID:27508340

  14. Quantitative proteomics of rat livers shows that unrestricted feeding is stressful for proteostasis with implications on life span.

    PubMed

    Gat-Yablonski, Galia; Finka, Andrija; Pinto, Galit; Quadroni, Manfredo; Shtaif, Biana; Goloubinoff, Pierre

    2016-08-01

    Studies in young mammals on the molecular effects of food restriction leading to prolong adult life are scares. Here, we used high-throughput quantitative proteomic analysis of whole rat livers to address the molecular basis for growth arrest and the apparent life-prolonging phenotype of the food restriction regimen. Over 1800 common proteins were significantly quantified in livers of ad libitum, restriction- and re-fed rats, which summed up into 92% of the total protein mass of the cells. Compared to restriction, ad libitum cells contained significantly less mitochondrial catabolic enzymes and more cytosolic and ER HSP90 and HSP70 chaperones, which are hallmarks of heat- and chemically-stressed tissues. Following re-feeding, levels of HSPs nearly reached ad libitum levels. The quantitative and qualitative protein values indicated that the restriction regimen was a least stressful condition that used minimal amounts of HSP-chaperones to maintain optimal protein homeostasis and sustain optimal life span. In contrast, the elevated levels of HSP-chaperones in ad libitum tissues were characteristic of a chronic stress, which in the long term could lead to early aging and shorter life span. PMID:27508340

  15. Transgenic rats overexpressing the human MrgX3 gene show cataracts and an abnormal skin phenotype

    SciTech Connect

    Kaisho, Yoshihiko . E-mail: Kaisho_Yoshihiko@takeda.co.jp; Watanabe, Takuya; Nakata, Mitsugu; Yano, Takashi; Yasuhara, Yoshitaka; Shimakawa, Kozo; Mori, Ikuo; Sakura, Yasufumi; Terao, Yasuko; Matsui, Hideki; Taketomi, Shigehisa

    2005-05-13

    The human MrgX3 gene, belonging to the mrgs/SNSRs (mass related genes/sensory neuron specific receptors) family, was overexpressed in transgenic rats using the actin promoter. Two animal lines showed cataracts with liquification/degeneration and swelling of the lens fiber cells. The transient epidermal desquamation was observed in line with higher gene expression. Histopathology of the transgenic rats showed acanthosis and focal parakeratosis. In the epidermis, there was an increase in cellular keratin 14, keratin 10, and loricrin, as well as PGP 9.5 in innervating nerve fibers. These phenotypes accompanied an increase in the number of proliferating cells. These results suggest that overexpression of the human MrgX3 gene causes a disturbance of the normal cell-differentiation process.

  16. Ethanol facilitation of short-term memory in adult rats with a disturbed circadian cycle.

    PubMed

    Mikolajczak, P; Okulicz-Kozaryn, I; Nowaczyk, M; Kaminska, E

    2001-01-01

    The aim of this study was to evaluate the effect of 3-month ethanol treatment on olfactory social memory test performance using two inter-exposure intervals [30 min: short-term recognition (STR); or 120 min: long-term recognition (LTR)] in adult rats with a disturbed circadian cycle (DCC). Ethanol treatment both in ethanol-preferring and -non-preferring groups improved the STR task compared to control rats. However, LTR procedure triggered the opposite tendency. Moreover, no differences between control rats with DCC and those with normal diurnal rhythm in STR and LTR paradigms were observed. Our results suggest that, under some conditions, alcohol facilitates short-term memory in adult rats. PMID:11468127

  17. Regeneration of central cholinergic neurones in the adult rat brain.

    PubMed

    Svendgaard, N A; Björklund, A; Stenevi, U

    1976-01-30

    The regrowth of lesioned central acetylcholinesterase (AChE)-positive axons in the adult rat was studied in irides implanted to two different brain sites: in the caudal diencephalon and hippocampus, and in the hippocampal fimbria. At both implantation sites the cholinergic septo-hippocampal pathways were transected. At 2-4 weeks after lesion, newly formed, probably sprouting fibres could be followed in abundance from the lesioned proximal axon stumps into the iris transplant. Growth of newly formed AChE-positive fibres into the transplant was also observed from lesioned axons in the anterior thalamus, and to a minor extent also from the dorsal and ventral tegmental AChE-positive pathways and the habenulo-interpeduncular tract. The regrowth process of the sprouting AChE-positive, presumed cholinergic fibres into the iris target was studied in further detail in whole-mount preparations of the transplants. For this purpose the irides were removed from the brain, unfolded, spread out on microscope slides, and then stained for AChE. During the first 2-4 weeks after transplantation the sprouting central fibres grew out over large areas of the iris. The new fibres branched profusely into a terminal plexus that covered maximally about half of the iris surface, and in some areas the patterning of the regenerated central fibres mimicked closely that of the normal autonomic cholinergic innervation of the iris. In one series of experiments the AChE-staining was combined with fluorescence histochemical visualization of regenerated adrenergic fibres in the same specimens. In many areas there was a striking congruence in the distributional patterns of the regenerated central cholinergic and adrenergic fibres in the transplant. This indicates that - as in the normal iris - the sprouting cholinergic axons (primarily originating in the lesioned septo-hippocampal pathways) and adrenergic axons (primarily originating in the lesioned axons of the locus neurones) regenerate together

  18. Cellular distribution and localisation of iron in adult rat brain ( substantia nigra)

    NASA Astrophysics Data System (ADS)

    Meinecke, Ch.; Morawski, M.; Reinert, T.; Arendt, T.; Butz, T.

    2006-08-01

    Iron appears to be one of the main factors in the metal induced neurodegeneration. Quantitative information on cellular, sub-cellular and cell specific distributions of iron is therefore important to assess. The investigations reported here were carried out on a brain from an adult rat. Therefore, 6 μm thick embedded, unstained brain sections containing the midbrain (substantia nigra, SN) were analysed. Particle induced X-ray emission (PIXE) using a focussed proton beam (beam - diameter app. 1 μm) was performed to determine the quantitative iron content on a cellular and sub-cellular level. The integral analysis shows that the iron content in the SN pars reticulata is twice as high than in the SN pars compacta. The analysis of the iron content on the cellular level revealed no remarkable differences between glia cells and neurons. This is in contrast to other studies using staining techniques.

  19. CYP 450 enzyme induction by chronic oral musk xylene in adult and developing rats.

    PubMed

    Suter-Eichenberger, R; Boelsterli, U A; Conscience-Egli, M; Lichtensteiger, W; Schlumpf, M

    2000-04-10

    Developmental and adult toxicity of musk xylene was studied in Long Evans (LE) rats fed with chow containing musk xylene (MX) in food pellets in concentrations of 1 mg, 10 mg, 33 mg, 100 mg and 1000 mg MX per 1 kg chow corresponding to a daily intake of 0.07-0.08 mg MX/kg up to 70-80 mg MX/kg body weight. Adult male and female rats were MX exposed for a minimum of 10 weeks before mating. Exposure continued throughout pregnancy, birth and lactation. The effects of MX on CYP1A1/1A2 were studied in liver microsomes by EROD (7-ethoxyresorufin-rosomes deethylase) for CYP1A1 and by MROD (methoxyresorufin-o-demethylase) for CYP1A2 activity and by Western blotting. MX induced these enzymes dose dependently in adult and developing rats at PN (postnatal day) 1 and 14. The lowest effective maternal dose was 2-3 mg MX/kg/day. Western blot data of CYP2B and CYP3A indicated the induction of both P450 enzyme proteins in developing rats at PN 14 at the higher dose of 70-80 mg MX/kg/day. In contrast, upon high MX exposure CYP2B but not CYP3A was found to be induced in adult first generation male and female rats, indicating differential sensitivity to MX in development.

  20. CYP 450 enzyme induction by chronic oral musk xylene in adult and developing rats.

    PubMed

    Suter-Eichenberger, R; Boelsterli, U A; Conscience-Egli, M; Lichtensteiger, W; Schlumpf, M

    1999-12-20

    Developmental and adult toxicity of musk xylene was studied in Long Evans (LE) rats fed with chow containing musk xylene (MX) in food pellets in concentrations of 1 mg, 10 mg, 33 mg, 100 mg and 1000 mg MX per 1 kg chow corresponding to a daily intake of 0.07-0.08 mg MX/kg up to 70-80 mg MX/kg body weight. Adult male and female rats were MX exposed for a minimum of 10 weeks before mating. Exposure continued throughout pregnancy, birth and lactation. The effects of MX on CYP1A1/1A2 were studied in liver microsomes by EROD (7-ethoxyresorufin-o-deethylase) for CYP1A1 and by MROD (methoxyresorufin-o-demethylase) for CYP1A2 activity and by Western blotting. MX induced these enzymes dose dependently in adult and developing rats at PN (postnatal day) 1 and 14. The lowest effective maternal dose was 2-3 mg MX/kg/day. Western blot data of CYP2B and CYP3A indicated the induction of both P450 enzyme proteins in developing rats at PN 14 at the higher dose of 70-80 mg MX/kg/day. In contrast, upon high MX exposure CYP2B but not CYP3A was found to be induced in adult first generation male and female rats, indicating differential sensitivity to MX in development.

  1. Developmental methoxychlor exposure affects multiple reproductive parameters and ovarian folliculogenesis and gene expression in adult rats.

    PubMed

    Armenti, AnnMarie E; Zama, Aparna Mahakali; Passantino, Lisa; Uzumcu, Mehmet

    2008-12-01

    Methoxychlor (MXC) is an organochlorine pesticide with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether transient developmental exposure to MXC could cause adult ovarian dysfunction, we exposed Fischer rats to 20 microg/kg/day (low dose; environmentally relevant dose) or 100 mg/kg/day (high dose) MXC between 19 days post coitum and postnatal day 7. Multiple reproductive parameters, serum hormone levels, and ovarian morphology and molecular markers were examined from prepubertal through adult stages. High dose MXC accelerated pubertal onset and first estrus, reduced litter size, and increased irregular cyclicity (P<0.05). MXC reduced superovulatory response to exogenous gonadotropins in prepubertal females (P<0.05). Rats exposed to high dose MXC had increasing irregular estrous cyclicity beginning at 4 months of age, with all animals showing abnormal cycles by 6 months. High dose MXC reduced serum progesterone, but increased luteinizing hormone (LH). Follicular composition analysis revealed an increase in the percentage of preantral and early antral follicles and a reduction in the percentage of corpora lutea in high dose MXC-treated ovaries (P<0.05). Immunohistochemical staining and quantification of the staining intensity showed that estrogen receptor beta was reduced by high dose MXC while anti-Mullerian hormone was upregulated by both low- and high dose MXC in preantral and early antral follicles (P<0.05). High dose MXC significantly reduced LH receptor expression in large antral follicles (P<0.01), and down-regulated cytochrome P450 side-chain cleavage. These results demonstrated that developmental MXC exposure results in reduced ovulation and fertility and premature aging, possibly by altering ovarian gene expression and folliculogenesis.

  2. Developmental methoxychlor exposure affects multiple reproductive parameters and ovarian folliculogenesis and gene expression in adult rats

    SciTech Connect

    Armenti, AnnMarie E.; Zama, Aparna Mahakali; Passantino, Lisa; Uzumcu, Mehmet

    2008-12-01

    Methoxychlor (MXC) is an organochlorine pesticide with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether transient developmental exposure to MXC could cause adult ovarian dysfunction, we exposed Fischer rats to 20 {mu}g/kg/day (low dose; environmentally relevant dose) or 100 mg/kg/day (high dose) MXC between 19 days post coitum and postnatal day 7. Multiple reproductive parameters, serum hormone levels, and ovarian morphology and molecular markers were examined from prepubertal through adult stages. High dose MXC accelerated pubertal onset and first estrus, reduced litter size, and increased irregular cyclicity (P < 0.05). MXC reduced superovulatory response to exogenous gonadotropins in prepubertal females (P < 0.05). Rats exposed to high dose MXC had increasing irregular estrous cyclicity beginning at 4 months of age, with all animals showing abnormal cycles by 6 months. High dose MXC reduced serum progesterone, but increased luteinizing hormone (LH). Follicular composition analysis revealed an increase in the percentage of preantral and early antral follicles and a reduction in the percentage of corpora lutea in high dose MXC-treated ovaries (P < 0.05). Immunohistochemical staining and quantification of the staining intensity showed that estrogen receptor {beta} was reduced by high dose MXC while anti-Mullerian hormone was upregulated by both low- and high dose MXC in preantral and early antral follicles (P < 0.05). High dose MXC significantly reduced LH receptor expression in large antral follicles (P < 0.01), and down-regulated cytochrome P450 side-chain cleavage. These results demonstrated that developmental MXC exposure results in reduced ovulation and fertility and premature aging, possibly by altering ovarian gene expression and folliculogenesis.

  3. Neonatal glucocorticoid treatment increased depression-like behaviour in adult rats.

    PubMed

    Ko, Meng-Chang; Hung, Yu-Hui; Ho, Pei-Yin; Yang, Yi-Ling; Lu, Kwok-Tung

    2014-12-01

    Synthetic glucocorticoid dexamethasone (DEX) is frequently used as a therapeutic agent to lessen the morbidity of chronic lung disease in premature infants. Previous studies suggested that neonatal DEX treatment altered brain development and cognitive function. It has been recognized that the amygdala is involved in emotional processes and also a critical site of neuronal plasticity for fear conditioning. Little is known about the possible long-term adverse effect of neonatal DEX treatment on amygdala function. The present study was aimed to evaluate the possible effect of neonatal DEX treatment on the synaptic function of amygdala in adult rats. Newborn Wistar rats were subjected to subcutaneous tapering-dose injections of DEX (0.5, 0.3 and 0.1 mg/kg) from post-natal day one to three, PN1-PN3. Animals were then subjected to a forced swimming test (FST) and electrophysiological recording aged eight weeks. The results of the FST showed neonatal DEX treatment increased depression-like behaviour in adulthood. After acute stress evoking, the percentage of time spent free floating is significantly increased in the DEX treated group compared with the control animals. Furthermore, neonatal DEX treatment elevated long-term potentiation (LTP) response and the phosphorylation level of MAPK in the lateral nucleus of amygdala (LA). Intracerebroventricular infusion of the MAPK inhibitor, PD98059, showed significant rescue effects including reduced depression-like behaviour and restoration of LTP to within normal range. In conclusion, our results suggested that MAPK signalling cascade in the LA plays an important role in the adverse effect of neonatal DEX treatment on amygdala function, which may result in adverse consequences in adult age, such as the enhancement of susceptibility for a depressive disorder in later life. PMID:24945924

  4. Triclosan exhibits a tendency to accumulate in the epididymis and shows sperm toxicity in male Sprague-Dawley rats.

    PubMed

    Lan, Zhou; Hyung Kim, Tae; Shun Bi, Kai; Hui Chen, Xiao; Sik Kim, Hyung

    2015-01-01

    Triclosan (TCS) is considered a potent endocrine disruptor that causes reproductive toxicity in non-mammals, but it is still unclear exactly whether TCS has adverse effects on the sperm or reproductive organs in mammals. In this study, we aimed to evaluate the distribution status of TCS in male reproductive organs of rats, and seek the correlation with the TCS-induced sperm toxicity or reproductive organ damage. Male rats were intragastrically administered with TCS at a dose of 50 mg/kg, the kinetics of TCS in the plasma and reproductive organs were investigated. TCS in testes and prostates both showed a lower-level distribution compared to that in the plasma, which indicates it has no tendency to accumulate in those organs. However, TCS in the epididymides showed a longer elimination half-life (t1/2 z), a longer the mean retention time (MRT), and a lower clearance (CLZ /F) compared with those in the plasma. Besides, the ratios of mean area under the concentration-time curve (AUC)(0-96 h(epididymides/plasma)) and AUC(0-∞(epididymides/plasma)) were 1.13 and 1.51, respectively. These kinetic parameters suggest TCS has an accumulation tendency in the epididymides. Based on this, we investigated the TCS-induced sperm toxicity and histopathological changes of reproductive organs in rats. TCS was given intragastrically at doses of 10, 50, and 200 mg/kg for 8 weeks. Rats treated with the high dose (200 mg/kg) of TCS showed a significant decrease in daily sperm production (DSP), changes in sperm morphology and epididymal histopathology. Considering the histopathological change in the epididymides, TCS may induce the epididymal damage due to the epididymal accumulation of that.

  5. Comparison of catalase immunoreactivity in the hippocampus between young, adult and aged mice and rats

    PubMed Central

    AHN, JI HYEON; CHEN, BAI HUI; SHIN, BICH-NA; LEE, TAE-KYEONG; CHO, JEONG HWI; KIM, IN HYE; PARK, JOON HA; LEE, JAE-CHUL; TAE, HYUN-JIN; LEE, CHOONG-HYUN; WON, MOO-HO; LEE, YUN LYUL; CHOI, SOO YOUNG; HONG, SEONGKWEON

    2016-01-01

    Catalase (CAT) is an important antioxidant enzyme and is crucial in modulating synaptic plasticity in the brain. In this study, CAT expression as well as neuronal distribution was compared in the hippocampus among young, adult and aged mice and rats. Male ICR mice and Sprague Dawley rats were used at postnatal month (PM) 1, PM 6 and PM 24 as the young, adult and aged groups, respectively (n=14/group). CAT expression was examined by immunohistochemistry and western blot analysis. In addition, neuronal distribution was examined by NeuN immunohistochemistry. In the present study, the mean number of NeuN-immunoreactive neurons was marginally decreased in mouse and rat hippocampi during aging, although this change was not identified to be significantly different. However, CAT immunoreactivity was significantly increased in pyramidal and granule neurons in the adult mouse and rat hippocampi and was significantly decreased in the aged mouse and rat hippocampi compared with that in the young animals. CAT protein levels in the hippocampus were also lowest in the aged mouse and rat hippocampus. These results indicate that CAT expression is significantly decreased in the hippocampi of aged animals and decreased CAT expression may be closely associated with aging. PMID:27221506

  6. Methylphenidate treatment leads to abnormalities on krebs cycle enzymes in the brain of young and adult rats.

    PubMed

    Réus, Gislaine Z; Scaini, Giselli; Furlanetto, Camila B; Morais, Meline O S; Jeremias, Isabela C; Mello-Santos, Lis Mairá; Freitas, Karolina V; Quevedo, João; Streck, Emilio L

    2013-08-01

    Studies have shown a relationship between energy metabolism and methylphenidate (MPH); however, there are no studies evaluating the effects of MPH in Krebs cycle. So, we investigated if MPH treatment could alter the activity of citrate synthase (CS), malate dehydrogenase (MD), and isocitrate dehydrogenase (ID) in the brain of young and adult Wistar rats. Our results showed that MPH (2 and 10 mg/kg) reduced CS in the striatum and prefrontal cortex (PF), with MPH at all doses in the cerebellum and hippocampus after chronic treatment in young rats. In adult rats the CS was reduced in the cerebellum after acute treatment with MPH at all doses, and after chronic treatment in the PF and cerebellum with MPH (10 mg/kg), and in the hippocampus with MPH (2 and 10 mg/kg). The ID decreased in the hippocampus and striatum with MPH (2 and 10 mg/kg), and in the cortex (10 mg/kg) after acute treatment in young rats. In adult rats acute treatment with MPH (2 and 10 mg/kg) reduced ID in the cerebellum, and with MPH (10 mg/kg) in the cortex; chronic treatment with MPH (10 mg/kg) decreased ID in the PF; with MPH (2 and 10 mg/kg) in the cerebellum, and with MPH at all doses in the hippocampus. The MD did not alter. In conclusion, our results suggest that MPH can alter enzymes of Krebs cycle in brain areas involved with circuits related with attention deficit hyperactivity disorder; however, such effects depend on age of animal and treatment regime.

  7. Behavioural changes induced by angiotensin-converting enzyme inhibition during pregnancy and lactation in adult offspring rats.

    PubMed

    Mecawi, A S; Araujo, I G; Fonseca, F V; Almeida-Pereira, G; Côrtes, W S; Rocha, F F; Reis, L C

    2009-05-01

    1. The use of angiotensin-converting enzyme (ACE) inhibitors during pregnancy is contraindicated because of their association with increased risks of fetopathy, including central nervous systems malformations. In addition, some reports have shown that renin-angiotensin system components are expressed differently during embryonic development and adulthood in the rat. 2. Because angiotensin II and its derivative peptides have been implicated in anxiety and modulation of nociception, the aim of the present study was to investigate whether inhibiting ACE during prenatal and neonatal periods would alter behavioural plasticity in adult male offspring rats. 3. Female Wistar rats were treated with captopril (2 mg/mL water; approximately 200 mg/kg per day) during pregnancy and lactation. At adulthood, the offspring were subjected to the open field, elevated plus maze, social interaction, forced swimming and tail flick tests. 4. Perinatal captopril treatment significantly increased ambulation (33%; P < 0.05) and decreased resting time (37.5%; P < 0.05) in the open field test. Perinatal captopril treatment did not alter any of the behavioural parameters of the elevated plus maze; however, captopril treatment did cause a significant increase in social interaction (75.3%; P < 0.05). In the forced swimming test, there was an increased latency period (102.9%; P < 0.001) and a decreased immobility period (38.7, P < 0.05) in rats treated with perinatal captopril. In the tail flick test, perinatal captopril treatment significantly reduced the latency time (26.3%; P < 0.01). 5. The data show that ACE inhibition during prenatal and neonatal periods affects behavioural responses in adult offspring rats, suggesting that ACE is required for the development of neural systems that are associated with adult anxiety and nociceptive behavioural responses.

  8. Adolescent nicotine exposure fails to impact cocaine reward, aversion and self-administration in adult male rats.

    PubMed

    Pomfrey, Rebecca L; Bostwick, Tamaara A; Wetzell, B Bradley; Riley, Anthony L

    2015-10-01

    The present experiments examined the effects of adolescent nicotine pre-exposure on the rewarding and aversive effects of cocaine and on cocaine self-administration in adult male rats. In Experiment 1, adolescent Sprague-Dawley rats (postnatal days 28-43) were given once daily injections of nicotine (0.6mg/kg) or vehicle and then tested for the aversive and rewarding effects of cocaine in a combined conditioned taste avoidance (CTA)/conditioned place preference (CPP) procedure in adulthood. In Experiment 2, adolescent Sprague-Dawley rats were pre-exposed to nicotine then tested for cocaine self-administration (0.25 or 0.75mg/kg), progressive ratio (PR) responding, extinction and cue-induced reinstatement in adulthood. In Experiment 1, rats showed significant dose-dependent cocaine-induced taste avoidance with cocaine-injected subjects consuming less saccharin over trials, but no effect of nicotine pre-exposure. For place preferences, cocaine induced significant place preferences with cocaine injected subjects spending significantly more time on the cocaine-paired side, but again there was no effect of nicotine history. All rats in Experiment 2 showed clear, dose-dependent responding during cocaine acquisition, PR testing, extinction and reinstatement with no effect of nicotine pre-exposure. These studies demonstrate that adolescent nicotine pre-exposure does not have an impact on cocaine's affective properties or its self-administration at least with the specific parametric conditions under which these effects were tested.

  9. Adolescent nicotine exposure fails to impact cocaine reward, aversion and self-administration in adult male rats.

    PubMed

    Pomfrey, Rebecca L; Bostwick, Tamaara A; Wetzell, B Bradley; Riley, Anthony L

    2015-10-01

    The present experiments examined the effects of adolescent nicotine pre-exposure on the rewarding and aversive effects of cocaine and on cocaine self-administration in adult male rats. In Experiment 1, adolescent Sprague-Dawley rats (postnatal days 28-43) were given once daily injections of nicotine (0.6mg/kg) or vehicle and then tested for the aversive and rewarding effects of cocaine in a combined conditioned taste avoidance (CTA)/conditioned place preference (CPP) procedure in adulthood. In Experiment 2, adolescent Sprague-Dawley rats were pre-exposed to nicotine then tested for cocaine self-administration (0.25 or 0.75mg/kg), progressive ratio (PR) responding, extinction and cue-induced reinstatement in adulthood. In Experiment 1, rats showed significant dose-dependent cocaine-induced taste avoidance with cocaine-injected subjects consuming less saccharin over trials, but no effect of nicotine pre-exposure. For place preferences, cocaine induced significant place preferences with cocaine injected subjects spending significantly more time on the cocaine-paired side, but again there was no effect of nicotine history. All rats in Experiment 2 showed clear, dose-dependent responding during cocaine acquisition, PR testing, extinction and reinstatement with no effect of nicotine pre-exposure. These studies demonstrate that adolescent nicotine pre-exposure does not have an impact on cocaine's affective properties or its self-administration at least with the specific parametric conditions under which these effects were tested. PMID:26255152

  10. Vitamin A Kinetics in Neonatal Rats vs. Adult Rats: Comparisons from Model-Based Compartmental Analysis12

    PubMed Central

    Tan, Libo; Green, Michael H; Ross, A Catharine

    2015-01-01

    A critical role for vitamin A (VA) in development is well established, but still relatively little is known about whole-body VA metabolism in early postnatal life. Recently, methods of mathematical modeling have begun to shed light on retinol kinetics in the postnatal growth period and on the effect of retinoid supplementation on retinol kinetics. Comparison of kinetic parameters from tracer studies in neonatal rats with those previously determined in models of VA metabolism in the adult suggests both similarities and differences in the relative transfer rates of plasma retinol to extrahepatic tissues, resulting in similarities and differences in kinetic parameters and inferences about physiologic processes. Similarities between neonatal and adult models include the capacity for efficient digestion and absorption of VA; characteristics of a high-response system; extensive retinol recycling among liver, plasma, and extrahepatic tissues; and comparable VA disposal rates. Differences between neonatal and adult models include that, in neonates, retinol turnover is faster and retinol recycling is much more extensive; there is a greater role for extrahepatic tissues in the uptake of chylomicron VA; and the intestine plays an important role in chylomicron VA uptake, especially in neonatal rats treated with a supplement containing VA. In summary, retinol kinetic modeling in the neonatal rat has provided a first view of whole-body VA metabolism in this age group and suggests that VA kinetics in neonatal rats differs in many ways from that in adults, perhaps reflecting an adaption to the lower VA concentration found in neonates compared with adults. PMID:25540407

  11. Effect of bisphenol A on morphology, apoptosis and proliferation in the resting mammary gland of the adult albino rat.

    PubMed

    Ibrahim, Marwa A A; Elbakry, Reda H; Bayomy, Naglaa A

    2016-02-01

    Bisphenol A (BPA) is a synthetic oestrogen that is extensively used in a wide range of daily used plastic products. This makes it one of the environmental chemicals that may have impact on human health. Due to its oestrogenic effect, BPA might affect the mammary gland. This study aimed to investigate the influence of BPA on the histological structure of the mammary gland of the adult female albino rat and its effect on epithelial cell proliferation and apoptosis status, in addition to its possible modulating effect on estrogen receptor expression. Thirty female adult albino rats were divided into control and experimental groups. The rats in the experimental group were gavaged with 5 mg/kg BPA daily for 8 weeks. The mammary glands were dissected and processed for histological and immunohistochemical stains for Ki-67, activated caspase-3 and estrogen receptor alpha (ER-α). BPA induced an increase in the number and size of the acini and ducts in the mammary gland of treated rats with hyperplasia of their lining epithelial cells. The collagen fibre content was significantly increased in the connective tissue stroma separating the ducts. Immunohistochemical results showed a significant increase in Ki-67 and caspase-3, but a non-significant increase in ER-α expression. Bisphenol A induced structural changes and affected the proliferation rate of mammary glands, so it might be one of the predisposing factors for breast cancer.

  12. The Effect of a Unilateral Orchiectomy before Gonadotoxic Treatment on the Contralateral Testis in Adult and Prepubertal Rats

    PubMed Central

    Rombaut, Charlotte; Faes, Katrien; Goossens, Ellen

    2016-01-01

    Purpose Previous studies have shown that the removal of one testis leads to a compensatory mechanism in the contralateral one, but this was species and age dependent. The aim of this study was to check whether this compensation would still occur after the combination of a unilateral orchiectomy and gonadotoxic treatment, since this resembles the clinical situation of patients who have to undergo highly toxic cancer treatment and therefore choose to cryopreserve a testicular biopsy for fertility restoration purposes. Materials & Methods Sprague Dawley rats underwent either unilateral orchiectomy, gonadotoxic busulfan treatment, the combination of both or served as fertile control. A comparison of the compensatory effects was made between adult and prepubertal treated rats. Mating experiments were performed, testosterone levels were followed-up, testicular weight was recorded and histology was analysed. Results Adult treated rats were able to restore fertility spontaneously in all treatment groups. On the other hand, 30% of the rats that underwent a unilateral orchiectomy and gonadotoxic treatment at prepubertal age showed hampered spermatogenesis, low testosterone levels, decreased testicular weights and were not able to reproduce. Conclusion This study emphasizes the need of fertility preservation strategies in prepubertal patients before gonadotoxic interventions. PMID:27768736

  13. Effect of bisphenol A on morphology, apoptosis and proliferation in the resting mammary gland of the adult albino rat.

    PubMed

    Ibrahim, Marwa A A; Elbakry, Reda H; Bayomy, Naglaa A

    2016-02-01

    Bisphenol A (BPA) is a synthetic oestrogen that is extensively used in a wide range of daily used plastic products. This makes it one of the environmental chemicals that may have impact on human health. Due to its oestrogenic effect, BPA might affect the mammary gland. This study aimed to investigate the influence of BPA on the histological structure of the mammary gland of the adult female albino rat and its effect on epithelial cell proliferation and apoptosis status, in addition to its possible modulating effect on estrogen receptor expression. Thirty female adult albino rats were divided into control and experimental groups. The rats in the experimental group were gavaged with 5 mg/kg BPA daily for 8 weeks. The mammary glands were dissected and processed for histological and immunohistochemical stains for Ki-67, activated caspase-3 and estrogen receptor alpha (ER-α). BPA induced an increase in the number and size of the acini and ducts in the mammary gland of treated rats with hyperplasia of their lining epithelial cells. The collagen fibre content was significantly increased in the connective tissue stroma separating the ducts. Immunohistochemical results showed a significant increase in Ki-67 and caspase-3, but a non-significant increase in ER-α expression. Bisphenol A induced structural changes and affected the proliferation rate of mammary glands, so it might be one of the predisposing factors for breast cancer. PMID:26877094

  14. Behavioral deficits in adult rats treated neonatally with glutamate.

    PubMed

    Hlinák, Zdenek; Gandalovicová, Dana; Krejcí, Ivan

    2005-01-01

    The present study evaluated long-term behavioral consequences of neonatal monosodium-l-glutamate (MSG) treatment in rats. The pups received MSG (3 mg/g sc) daily from postnatal day (PD) 5-12. Data from an automatic activity monitor showed that locomotion of MSG-treated females and males aged 56 and 84 days was significantly reduced. Beginning PD 120, three behavioral tests were performed. As compared to the controls, in the elevated plus maze test, modified to evaluate the adaptive form of spatial memory, MSG-treated animals of both sex had significantly prolonged start and transfer latencies. In the social recognition test, assessing olfactory working memory, MSG-treated males displayed a reduced interest in the juvenile conspecific as the stimulus partner during both the initial exposure and re-exposure performed 30 min later. In the open field test, a significant decrease in the habituation rate was found in MSG-treated animals. Sex-dependent differences in behavioral performance were suggested in the open field and elevated plus maze tests. Behavioral changes are discussed in light of the deficits in perception and processing of visual and olfactory stimuli.

  15. Effects of subchronic inhalation of low concentrations of nitrogen dioxide. 1. The proximal alveolar region of juvenile and adult rats

    SciTech Connect

    Chang, L.Y.; Graham, J.A.; Miller, F.J.; Ospital, J.J.; Crapo, J.D.

    1986-01-01

    Techniques were devised to isolate tissue from the epithelium of terminal airways and the alveoli proximal to the airways. One-day-old juveniles and six week old adult rats were exposed to either room air or 0.5 ppm NO/sub 2/ for 23 hrs per day seven days per week. An additional group of adult rats were exposed to 2.0 ppm NO/sub 2/ for the same duration. Two daily hour spikes to three times the background levels (0.5 to 1.5 ppm and 2.0 to 6.0 ppm) were applied Mon. through Fri. Morphometric analysis revealed that epithelial injury occurred in all exposed animals. The juvenile rats which had been exposed to 0.5 ppm NO/sub 2/ exhibited changes in the characteristics of type II epithelial cells. These cells spread to cover more alveolar surface and became thinner. Adult animals exposed to 0.5 and 2.0 ppm NO/sub 2/ showed changes in alveolar macrophages and in the alveolar interstitium in addition to changes in the epithelium.

  16. Periodic maternal deprivation induces gender-dependent alterations in behavioral and neuroendocrine responses to emotional stress in adult rats.

    PubMed

    Wigger, A; Neumann, I D

    1999-04-01

    There is evidence that stressful events during the neonatal "stress hyporesponsive period" may influence both emotional behavior and the maturation of the hypothalamic-pituitary-adrenal (HPA) axis in rats. We tested whether periodic maternal deprivation (180 min daily on postnatal days 3-10, PMD) caused chronic changes in emotional behavior and HPA axis activity in either male or female adult rats, or both. In addition, HPA secretory responses to human/rat corticotropin-releasing factor (CRH, 50 ng/kg i.v.) were determined in the adult males. In the elevated plus-maze test, adult (4-5 months of age) PMD-treated animals of both sexes displayed increased anxiety-related behavior compared to control rats. This was indicated by a reduction in the number of entries (male: 70% reduction, p < 0.01; female: 31% reduction, p < 0.01) and amount of time spent on the open arms (male: 86% reduction, p < 0.01; female: 40% reduction, NS). Neuroendocrine parameters were also altered in PMD-treated rats in a gender-dependent manner. Whereas basal plasma adrenocorticotropin (ACTH) and corticosterone levels did not differ significantly between PMD and control groups of either sex, the ACTH response to elevated plus-maze exposure, a predominantly emotional stressor, was higher in male (p < 0.01), but not female, PMD animals than in the respective controls. In contrast, PMD had no effect on behavioral (duration of struggling) or HPA axis responses to forced swimming (90 s, 19 degrees C), a complex and predominantly physical stressor, in either male or female rats. In response to CRH stimulation, PMD-treated males did not show differences in the ACTH secretion compared to controls, indicating alterations in HPA axis regulation at a suprapituitary level. Thus, PMD caused long-term changes in the emotional behavior of adult rats of both sexes, although to a differing degree in males and females, whereas it appeared to cause predominantly alterations in the HPA axis response in males

  17. Embedding a Panoramic Representation of Infrared Light in the Adult Rat Somatosensory Cortex through a Sensory Neuroprosthesis

    PubMed Central

    Hartmann, Konstantin; Thomson, Eric E.; Zea, Ivan; Yun, Richy; Mullen, Peter; Canarick, Jay; Huh, Albert

    2016-01-01

    Can the adult brain assimilate a novel, topographically organized, sensory modality into its perceptual repertoire? To test this, we implemented a microstimulation-based neuroprosthesis that rats used to discriminate among infrared (IR) light sources. This system continuously relayed information from four IR sensors that were distributed to provide a panoramic view of IR sources, into primary somatosensory cortex (S1). Rats learned to discriminate the location of IR sources in <4 d. Animals in which IR information was delivered in spatial register with whisker topography learned the task more quickly. Further, in animals that had learned to use the prosthesis, altering the topographic mapping from IR sensor to stimulating electrode had immediate deleterious effects on discrimination performance. Multielectrode recordings revealed that S1 neurons had multimodal (tactile/IR) receptive fields, with clear preferences for those stimuli most likely to be delivered during the task. Neuronal populations predicted, with high accuracy, which stimulation pattern was present in small (75 ms) time windows. Surprisingly, when identical microstimulation patterns were delivered during an unrelated task, cortical activity in S1 was strongly suppressed. Overall, these results show that the adult mammalian neocortex can readily absorb completely new information sources into its representational repertoire, and use this information in the production of adaptive behaviors. SIGNIFICANCE STATEMENT Understanding the potential for plasticity in the adult brain is a key goal for basic neuroscience and modern rehabilitative medicine. Our study examines one dimension of this challenge: how malleable is sensory processing in adult mammals? We implemented a panoramic infrared (IR) sensory prosthetic system in rats; it consisted of four IR sensors equally spaced around the circumference of the head of the rat. Each sensor was coupled to a microstimulating electrode placed in the somatosensory

  18. Effects of monomethylarsonic and monomethylarsonous acid on evoked synaptic potentials in hippocampal slices of adult and young rats

    SciTech Connect

    Krueger, Katharina Straub, Heidrun; Hirner, Alfred V.; Hippler, Joerg; Binding, Norbert; Musshoff, Ulrich

    2009-04-01

    Arsenite and its metabolites, dimethylarsinic or dimethylarsinous acid, have previously been shown to disturb synaptic transmission in hippocampal slices of rats (Krueger, K., Gruner, J., Madeja, M., Hartmann, L.M., Hirner, A.V., Binding, N., Mu{beta}hoff, U., 2006a. Blockade and enhancement of glutamate receptor responses in Xenopus oocytes by methylated arsenicals. Arch. Toxicol. 80, 492-501, Krueger, K., Straub, H., Binding, N., Mu{beta}hoff, U., 2006b. Effects of arsenite on long-term potentiation in hippocampal slices from adult and young rats. Toxicol. Lett. 165, 167-173, Krueger, K., Repges, H., Hippler, J., Hartmann, L.M., Hirner, A.V., Straub, H., Binding, N., Mu{beta}hoff, U., 2007. Effects of dimethylarsinic and dimethylarsinous acid on evoked synaptic potentials in hippocampal slices of young and adult rats. Toxicol. Appl. Pharmacol. 225, 40-46). The present experiments investigate, whether the important arsenic metabolites monomethylarsonic acid (MMA{sup V}) and monomethylarsonous acid (MMA{sup III}) also influence the synaptic functions of the hippocampus. In hippocampal slices of young (14-21 days-old) and adult (2-4 months-old) rats, evoked synaptic field potentials from the Schaffer collateral-CA1 synapse were measured under control conditions and during and after 30 and 60 min of application of the arsenic compounds. MMA{sup V} had no effect on the synapse functions neither in slices of adult nor in those from young rats. However, MMA{sup III} strongly influenced the synaptic transmission: it totally depressed the amplitudes of fEPSPs at concentrations of 50 {mu}mol/l (adult rats) and 25 {mu}mol/l (young rats) and LTP amplitudes at concentrations of 25 {mu}mol/l (adult rats) and 10 {mu}mol/l (young rats), respectively. In contrast, application of 1 {mu}mol/l MMA{sup III} led to an enhancement of the LTP amplitude in young rats, which is interpretable by an enhancing effect on NMDA receptors and a lack of the blocking effect on AMPA receptors at

  19. Circadian rhythm of intraocular pressure in the adult rat.

    PubMed

    Lozano, Diana C; Hartwick, Andrew T E; Twa, Michael D

    2015-05-01

    Ocular hypertension is a risk factor for developing glaucoma, which consists of a group of optic neuropathies characterized by progressive degeneration of retinal ganglion cells and subsequent irreversible vision loss. Our understanding of how intraocular pressure damages the optic nerve is based on clinical measures of intraocular pressure that only gives a partial view of the dynamic pressure load inside the eye. Intraocular pressure varies over the course of the day and the oscillator regulating these daily changes has not yet been conclusively identified. The purpose of this study was to compare and contrast the circadian rhythms of intraocular pressure and body temperature in Brown Norway rats when these animals are housed in standard light-dark and continuous dim light (40-90 lux) conditions. The results from this study show that the temperature rhythm measured in continuous dim light drifted forward relative to external time, indicating that the rhythm was free running and being regulated by an internal biological clock. Also, the results show that there is a persistent, but dampened, circadian rhythm of intraocular pressure in continuous dim light and that the circadian rhythms of temperature and intraocular pressure are not synchronized by the same central oscillator. We conclude that once- or twice-daily clinical measures of intraocular pressure are insufficient to describe intraocular pressure dynamics. Similarly, our results indicate that, in experimental animal models of glaucoma, the common practice of housing animals in constant light does not necessarily eliminate the potential influence of intraocular pressure rhythms on the progression of nerve damage. Future studies should aim to determine whether an oscillator within the eye regulates the rhythm of intraocular pressure and to better characterize the impact of glaucoma on this rhythm.

  20. Treatment with tianeptine induces antidepressive-like effects and alters the neurotrophin levels, mitochondrial respiratory chain and cycle Krebs enzymes in the brain of maternally deprived adult rats.

    PubMed

    Della, Franciela P; Abelaira, Helena M; Réus, Gislaine Z; Santos, Maria Augusta B dos; Tomaz, Débora B; Antunes, Altamir R; Scaini, Giselli; Morais, Meline O S; Streck, Emilio L; Quevedo, João

    2013-03-01

    Maternally deprived rats were treated with tianeptine (15 mg/kg) once a day for 14 days during their adult phase. Their behavior was then assessed using the forced swimming and open field tests. The BDNF, NGF and energy metabolism were assessed in the rat brain. Deprived rats increased the immobility time, but tianeptine reversed this effect and increased the swimming time; the BDNF levels were decreased in the amygdala of the deprived rats treated with saline and the BDNF levels were decreased in the nucleus accumbens within all groups; the NGF was found to have decreased in the hippocampus, amygdala and nucleus accumbens of the deprived rats; citrate synthase was increased in the hippocampus of non-deprived rats treated with tianeptine and the creatine kinase was decreased in the hippocampus and amygdala of the deprived rats; the mitochondrial complex I and II-III were inhibited, and tianeptine increased the mitochondrial complex II and IV in the hippocampus of the non-deprived rats; the succinate dehydrogenase was increased in the hippocampus of non-deprived rats treated with tianeptine. So, tianeptine showed antidepressant effects conducted on maternally deprived rats, and this can be attributed to its action on the neurochemical pathways related to depression.

  1. Treatment with tianeptine induces antidepressive-like effects and alters the neurotrophin levels, mitochondrial respiratory chain and cycle Krebs enzymes in the brain of maternally deprived adult rats.

    PubMed

    Della, Franciela P; Abelaira, Helena M; Réus, Gislaine Z; Santos, Maria Augusta B dos; Tomaz, Débora B; Antunes, Altamir R; Scaini, Giselli; Morais, Meline O S; Streck, Emilio L; Quevedo, João

    2013-03-01

    Maternally deprived rats were treated with tianeptine (15 mg/kg) once a day for 14 days during their adult phase. Their behavior was then assessed using the forced swimming and open field tests. The BDNF, NGF and energy metabolism were assessed in the rat brain. Deprived rats increased the immobility time, but tianeptine reversed this effect and increased the swimming time; the BDNF levels were decreased in the amygdala of the deprived rats treated with saline and the BDNF levels were decreased in the nucleus accumbens within all groups; the NGF was found to have decreased in the hippocampus, amygdala and nucleus accumbens of the deprived rats; citrate synthase was increased in the hippocampus of non-deprived rats treated with tianeptine and the creatine kinase was decreased in the hippocampus and amygdala of the deprived rats; the mitochondrial complex I and II-III were inhibited, and tianeptine increased the mitochondrial complex II and IV in the hippocampus of the non-deprived rats; the succinate dehydrogenase was increased in the hippocampus of non-deprived rats treated with tianeptine. So, tianeptine showed antidepressant effects conducted on maternally deprived rats, and this can be attributed to its action on the neurochemical pathways related to depression. PMID:23325329

  2. Pharmacokinetics of bisphenol A in neonatal and adult Sprague-Dawley rats

    SciTech Connect

    Doerge, Daniel R.; Twaddle, Nathan C.; Vanlandingham, Michelle; Fisher, Jeffrey W.

    2010-09-01

    Bisphenol A (BPA) is an important industrial chemical used in the manufacture of polycarbonate plastic products and epoxy resin-based food can liners. The presence of BPA in urine of > 90% of Americans aged 6-60 suggests ubiquitous and frequent exposure. The current study used LC/MS/MS to measure serum pharmacokinetics of aglycone (active) and conjugated (inactive) BPA in adult and neonatal Sprague-Dawley rats by oral and injection routes. Deuterated BPA was used to avoid issues of background contamination. Linear pharmacokinetics were observed in adult rats treated orally in the range of 0-200 {mu}g/kg bw. Evidence for enterohepatic recirculation of conjugated, but not aglycone, BPA was observed in adult rats. Significant inverse relationships were observed between postnatal age and measures of internal exposures to aglycone BPA and its elimination. In neonatal rats treated orally, internal exposures to aglycone BPA were substantially lower than from subcutaneous injection. The results reinforce the critical role for first-pass Phase II metabolism of BPA in gut and liver after oral exposure that attenuates internal exposure to the aglycone form in rats of all ages. The internal exposures to aglycone BPA observed in adult and neonatal rats following a single oral dose of 100 {mu}g/kg bw are inconsistent with effects mediated by classical estrogen receptors based on binding affinities. However, an impact on alternative estrogen signaling pathways that have higher receptor affinity cannot be excluded in neonatal rats. These findings emphasize the importance of matching aglycone BPA internal dosimetry with receptor affinities in experimental animal studies reporting toxicity.

  3. Neurobehavioral assessment following e-cigarette refill liquid exposure in adult rats.

    PubMed

    Golli, Narges El; Dallagi, Yosra; Rahali, Dalila; Rejeb, Ines; Fazaa, Saloua El

    2016-07-01

    The present study was conducted to assess the toxic effect of e-cigarette refill liquid on cognitive and motor functions in adult rats. Animals were administered 28 μl/kg of body weight of e-liquid with/without a dose of 0.5 mg of nicotine/kg of body weight, using the intraperitoneally route for a period of 4 weeks. They were then evaluated by novel object recognition test (NORT) and spontaneous alternation T-maze test for cognitive functions. Results indicated that e-liquid without nicotine induced, in the NORT, a decrease in time exploring the novel object during the test session and lower discrimination and recognition indexes compared to control and e-liquid with nicotine treated rats. Furthermore, short-term spatial memory was affected after e-liquid treatment in the spontaneous alternation T-maze test, identifying recognition memory impairments. However, none of the treatments altered motor functions assessed by inclined plane test, Kondziela's inverted screen test and weights test. Cell cytotoxicity assessment following e-liquid exposure showed a significant decrease in hippocampal cell viability, but no change in cortical cell viability. Thereby, e-liquid without nicotine causes cognitive impairments, especially on the hippocampus. Based on these results, more extensive assessments on e-cigarettes must be carried out. PMID:27401341

  4. Effect of hindlimb unloading on motor activity in adult rats: impact of prenatal stress.

    PubMed

    Canu, M H; Darnaudéry, M; Falempin, M; Maccari, S; Viltart, O

    2007-02-01

    Environmental changes that occur in daily life or, in particular, in situations like actual or simulated microgravity require neuronal adaptation of sensory and motor functions. Such conditions can exert long-lasting disturbances on an individual's adaptive ability. Additionally, prenatal stress also leads to behavioral and physiological abnormalities in adulthood. Therefore, the aims of the present study were (a) to evaluate in adult rats the behavioral motor adaptation that follows 14 days of exposure to simulated microgravity (hindlimb unloading) and (b) to determine whether restraint prenatal stress influences this motor adaptation. For this purpose, the authors assessed rats' motor reactivity to novelty, their skilled walking on a ladder, and their swimming performance. Results showed that unloading severely impaired motor activity and skilled walking. By contrast, it had no effect on swimming performance. Moreover, results demonstrated for the first time that restraint prenatal stress exacerbates the effects of unloading. These results are consistent with the role of a steady prenatal environment in allowing an adequate development and maturation of sensorimotor systems to generate adapted responses to environmental challenges during adulthood. PMID:17324062

  5. Neurobehavioral assessment following e-cigarette refill liquid exposure in adult rats.

    PubMed

    Golli, Narges El; Dallagi, Yosra; Rahali, Dalila; Rejeb, Ines; Fazaa, Saloua El

    2016-07-01

    The present study was conducted to assess the toxic effect of e-cigarette refill liquid on cognitive and motor functions in adult rats. Animals were administered 28 μl/kg of body weight of e-liquid with/without a dose of 0.5 mg of nicotine/kg of body weight, using the intraperitoneally route for a period of 4 weeks. They were then evaluated by novel object recognition test (NORT) and spontaneous alternation T-maze test for cognitive functions. Results indicated that e-liquid without nicotine induced, in the NORT, a decrease in time exploring the novel object during the test session and lower discrimination and recognition indexes compared to control and e-liquid with nicotine treated rats. Furthermore, short-term spatial memory was affected after e-liquid treatment in the spontaneous alternation T-maze test, identifying recognition memory impairments. However, none of the treatments altered motor functions assessed by inclined plane test, Kondziela's inverted screen test and weights test. Cell cytotoxicity assessment following e-liquid exposure showed a significant decrease in hippocampal cell viability, but no change in cortical cell viability. Thereby, e-liquid without nicotine causes cognitive impairments, especially on the hippocampus. Based on these results, more extensive assessments on e-cigarettes must be carried out.

  6. Thyroxine binding to serum thyronine-binding globulin in thyroidectomized adult and normal neonatal rats

    SciTech Connect

    Young, R.A.; Meyers, B.; Alex, S.; Fang, S.L.; Braverman, L.E.

    1988-05-01

    The amount of tracer (125I)T4 bound to serum thyronine-binding globulin (TBG) was measured by polyacrylamide gel electrophoresis in adult thyroidectomized (TX) rats and normal 1-day to 4-week-old rat puts. Thyroidectomy was associated with the appearance of significant amounts of (125I)T4 binding to serum TBG in lean rats, but not in obese Zucker rats. Treatment of the TX rats in vivo with replacement doses of T4 prevented this increase in TBG binding, but enrichment of serum from TX rats with T4 did not. Significant amounts of tracer (125I)T4 binding to TBG was present in serum from 1- to 3-week-old normal rat pups, but not in 1-day- or 4-week-old pups. There were significantly higher levels of TBG binding of (125I)T4 in serum from 2-week-old rat pups raised in litters of 16 pups compared to those raised in litters of 4 pups. All manipulations that result in the appearance of TBG in rat serum also result in either weight loss or a slowing in the rate of growth, suggesting that the appearance of TBG in rat serum has a nutritional component. This possibility is further supported by the observations that increases in TBG binding of (125I)T4 are not found in obese Zucker rats fed a low protein-high carbohydrate diet for 14 days or fasted for 7 days, or after thyroidectomy, perhaps owing to the large stores of fuel in the obese rat.

  7. The ependymal region of the adult human spinal cord differs from other species and shows ependymoma-like features.

    PubMed

    Garcia-Ovejero, Daniel; Arevalo-Martin, Angel; Paniagua-Torija, Beatriz; Florensa-Vila, José; Ferrer, Isidro; Grassner, Lukas; Molina-Holgado, Eduardo

    2015-06-01

    Several laboratories have described the existence of undifferentiated precursor cells that may act like stem cells in the ependyma of the rodent spinal cord. However, there are reports showing that this region is occluded and disassembled in humans after the second decade of life, although this has been largely ignored or interpreted as a post-mortem artefact. To gain insight into the patency, actual structure, and molecular properties of the adult human spinal cord ependymal region, we followed three approaches: (i) with MRI, we estimated the central canal patency in 59 control subjects, 99 patients with traumatic spinal cord injury, and 26 patients with non-traumatic spinal cord injuries. We observed that the central canal is absent from the vast majority of individuals beyond the age of 18 years, gender-independently, throughout the entire length of the spinal cord, both in healthy controls and after injury; (ii) with histology and immunohistochemistry, we describe morphological properties of the non-lesioned ependymal region, which showed the presence of perivascular pseudorosettes, a common feature of ependymoma; and (iii) with laser capture microdissection, followed by TaqMan® low density arrays, we studied the gene expression profile of the ependymal region and found that it is mainly enriched in genes compatible with a low grade or quiescent ependymoma (53 genes); this region is enriched only in 14 genes related to neurogenic niches. In summary, we demonstrate here that the central canal is mainly absent in the adult human spinal cord and is replaced by a structure morphologically and molecularly different from that described for rodents and other primates. The presented data suggest that the ependymal region is more likely to be reminiscent of a low-grade ependymoma. Therefore, a direct translation to adult human patients of an eventual therapeutic potential of this region based on animal models should be approached with caution. PMID:25882650

  8. The ependymal region of the adult human spinal cord differs from other species and shows ependymoma-like features.

    PubMed

    Garcia-Ovejero, Daniel; Arevalo-Martin, Angel; Paniagua-Torija, Beatriz; Florensa-Vila, José; Ferrer, Isidro; Grassner, Lukas; Molina-Holgado, Eduardo

    2015-06-01

    Several laboratories have described the existence of undifferentiated precursor cells that may act like stem cells in the ependyma of the rodent spinal cord. However, there are reports showing that this region is occluded and disassembled in humans after the second decade of life, although this has been largely ignored or interpreted as a post-mortem artefact. To gain insight into the patency, actual structure, and molecular properties of the adult human spinal cord ependymal region, we followed three approaches: (i) with MRI, we estimated the central canal patency in 59 control subjects, 99 patients with traumatic spinal cord injury, and 26 patients with non-traumatic spinal cord injuries. We observed that the central canal is absent from the vast majority of individuals beyond the age of 18 years, gender-independently, throughout the entire length of the spinal cord, both in healthy controls and after injury; (ii) with histology and immunohistochemistry, we describe morphological properties of the non-lesioned ependymal region, which showed the presence of perivascular pseudorosettes, a common feature of ependymoma; and (iii) with laser capture microdissection, followed by TaqMan® low density arrays, we studied the gene expression profile of the ependymal region and found that it is mainly enriched in genes compatible with a low grade or quiescent ependymoma (53 genes); this region is enriched only in 14 genes related to neurogenic niches. In summary, we demonstrate here that the central canal is mainly absent in the adult human spinal cord and is replaced by a structure morphologically and molecularly different from that described for rodents and other primates. The presented data suggest that the ependymal region is more likely to be reminiscent of a low-grade ependymoma. Therefore, a direct translation to adult human patients of an eventual therapeutic potential of this region based on animal models should be approached with caution.

  9. High neuronal/astroglial differentiation plasticity of adult rat hippocampal neural stem/progenitor cells in response to the effects of embryonic and adult cerebrospinal fluids

    PubMed Central

    Peirouvi, T.; Yekani, F.; Azarnia, M.; Massumi, M.

    2015-01-01

    Hippocampal neural stem/progenitor cells (hipp-NS/PCs) of the adult mammalian brain are important sources of neuronal and gial cell production. In this study, the main goal is to investigate the plasticity of these cells in neuronal/astroglial differentiations. To this end, the differentiation of the hipp-NS/PCs isolated from 3-month-old Wistar rats was investigated in response to the embryonic cerebrospinal fluid (E-CSF) including E13.5, E17-CSF and the adult cerebrospinal fluid (A-CSF), all extracted from rats. CSF samples were selected based on their effects on cell behavioral parameters. Primary cell culture was performed in the presence of either normal or high levels of KCL in a culture medium. High levels of KCL cause cell depolarization, and thus the activation of quiescent NSCs. Results from immunocytochemistry (ICC) and semi-quantitative RT-PCR (sRT-PCR) techniques showed that in E-CSF-treated groups, neuronal differentiation increased (E17>E13.5). In contrast, A-CSF decreased and increased neuronal and astroglial differentiations, respectively. Cell survivability and/or proliferation (S/P), evaluated by an MTT assay, increased by E13.5 CSF, but decreased by both E17 CSF and A-CSF. Based on the results, it is finally concluded that adult rat hippocampal proliferative cells are not restricted progenitors but rather show high plasticity in neuronal/astroglial differentiation according to the effects of CSF samples. In addition, using high concentrations of KCL in the primary cell culture led to an increase in the number of NSCs, which in turn resulted in the increase in neuronal or astroglial differentiations after CSF treatment. PMID:27175157

  10. Brain apoptosis signaling pathways are regulated by methylphenidate treatment in young and adult rats.

    PubMed

    Réus, Gislaine Z; Scaini, Giselli; Jeremias, Gabriela C; Furlanetto, Camila B; Morais, Meline O S; Mello-Santos, Lis Maira; Quevedo, João; Streck, Emilio L

    2014-10-01

    Methylphenidate (MPH) is commonly prescribed for children who have been diagnosed with attention deficit hyperactivity disorder (ADHD); however, the action mechanisms of methylphenidate have not been fully elucidated. Studies have shown a relationship between apoptosis signaling pathways and psychiatric disorders, as well as in therapeutic targets for such disorders. So, we investigated if chronic treatment with MPH at doses of 1, 2 and 10mg/kg could alter the levels of pro-apoptotic protein, Bax, anti-apoptotic protein, Bcl-2, caspase-3 and cytochrome c in the brain of young and adult Wistar rats. Our results showed that MPH at all doses increased Bax in the cortex; the Bcl-2 and caspase-3 were increased with MPH (1mg/kg) and were reduced with MPH (2 and 10mg/kg); the cytochrome c was reduced in the cortex after treatment with MPH at all doses; in the cerebellum there was an increase of Bax with MPH at all doses, however, there was a reduction of Bcl-2, caspase-3, and cytochrome c with MPH (2 and 10mg/kg); in the striatum the treatment with MPH (10mg/kg) decreased caspase-3 and cytochrome c; treatment with MPH (2 and 10mg/kg) increased Bax and decreased Bcl-2 in the hippocampus; and the caspase-3 and cytochrome c were reduced in the hippocampus with MPH (10mg/kg). In conclusion, our results suggest that MPH influences plasticity in the brain of young and adult rats; however, the effects were dependent of age and brain area, on the one hand activating the initial cascade of apoptosis, increasing Bax and reducing Bcl-2, but otherwise inhibiting apoptosis by reduction of caspase-3 and cytochrome c. PMID:25128604

  11. Extensor motoneurone properties are altered immediately before and during fictive locomotion in the adult decerebrate rat.

    PubMed

    MacDonell, C W; Power, K E; Chopek, J W; Gardiner, K R; Gardiner, P F

    2015-05-15

    This study examined motoneurone properties during fictive locomotion in the adult rat for the first time. Fictive locomotion was induced via electrical stimulation of the mesencephalic locomotor region in decerebrate adult rats under neuromuscular blockade to compare basic and rhythmic motoneurone properties in antidromically identified extensor motoneurones during: (1) quiescence, before and after fictive locomotion; (2) the 'tonic' period immediately preceding locomotor-like activity, whereby the amplitude of peripheral flexor (peroneal) and extensor (tibial) nerves are increased but alternation has not yet occurred; and (3) locomotor-like episodes. Locomotion was identified by alternating flexor-extensor nerve activity, where the motoneurone either produced membrane oscillations consistent with a locomotor drive potential (LDP) or did not display membrane oscillation during alternating nerve activity. Cells producing LDPs were referred to as such, while those that did not were referred to as 'idle' motoneurones. LDP and idle motoneurones during locomotion had hyperpolarized spike threshold (Vth ; LDP: 3.8 mV; idle: 5.8 mV), decreased rheobase and an increased discharge rate (LDP: 64%; idle: 41%) during triangular ramp current injection even though the frequency-current slope was reduced by 70% and 55%, respectively. Modulation began in the tonic period immediately preceding locomotion, with a hyperpolarized Vth and reduced rheobase. Spike frequency adaptation did not occur in spiking LDPs or firing generated from sinusoidal current injection, but occurred during a sustained current pulse during locomotion. Input conductance showed no change. Results suggest motoneurone modulation occurs across the pool and is not restricted to motoneurones engaged in locomotion. PMID:25809835

  12. Prenatal cocaine exposure alters progenitor cell markers in the subventricular zone of the adult rat brain

    PubMed Central

    Patel, Dhyanesh Arvind; Booze, Rosemarie M.; Mactutus, Charles F.

    2013-01-01

    Long-term consequences of early developmental exposure to drugs of abuse may have deleterious effects on the proliferative plasticity of the brain. The purpose of this study was to examine the long-term effects of prenatal exposure to cocaine, using the IV route of administration and doses that mimic the peak arterial levels of cocaine use in humans, on the proliferative cell types of the subventricular zones (SVZ) in the adult (180 days-old) rat brain. Employing immunocytochemistry, the expression of GFAP+ (type B cells) and nestin+(GFAP−) (Type C and A cells) staining was quantified in the subcallosal area of the SVZ. GFAP+ expression was significantly different between the prenatal cocaine treated group and the vehicle (saline) control group. The prenatal cocaine treated group possessed significantly lower GFAP+ expression relative to the vehicle control group, suggesting that prenatal cocaine exposure significantly reduced the expression of type B neural stem cells of the SVZ. In addition, there was a significant sex difference in nestin+ expression with females showing approximately 8–13% higher nestin+ expression compared to the males. More importantly, a significant prenatal treatment condition (prenatal cocaine, control) by sex interaction in nestin+ expression was confirmed, indicating different effects of cocaine based on sex of the animal. Specifically, prenatal cocaine exposure eliminated the basal difference between the sexes. Collectively, the present findings suggest that prenatal exposure to cocaine, when delivered via a protocol designed to capture prominent features of recreational usage, can selectively alter the major proliferative cell types in the subcallosal area of the SVZ in an adult rat brain, and does so differently for males and females. PMID:22119286

  13. Inhibition of Adult Rat Retinal Ganglion Cells by D1-type Dopamine Receptor Activation

    PubMed Central

    Hayashida, Yuki; Rodríguez, Carolina Varela; Ogata, Genki; Partida, Gloria J.; Oi, Hanako; Stradleigh, Tyler W.; Lee, Sherwin C.; Colado, Anselmo Felipe; Ishida, Andrew T.

    2011-01-01

    The spike output of neural pathways can be regulated by modulating output neuron excitability and/or their synaptic inputs. Dopaminergic interneurons synapse onto cells that route signals to mammalian retinal ganglion cells, but it is unknown whether dopamine can activate receptors in these ganglion cells and, if it does, how this affects their excitability. Here, we show D1a-receptor-like immunoreactivity in ganglion cells identified in adult rats by retrogradely transported dextran, and that dopamine, D1-type receptor agonists, and cAMP analogs inhibit spiking in ganglion cells dissociated from adult rats. These ligands curtailed repetitive spiking during constant current injections, and reduced the number and rate of rise of spikes elicited by fluctuating current injections without significantly altering the timing of the remaining spikes. Consistent with mediation by D1-type receptors, SCH-23390 reversed the effects of dopamine on spikes. Contrary to a recent report, spike inhibition by dopamine was not precluded by blocking Ih. Consistent with the reduced rate of spike rise, dopamine reduced voltage-gated Na+ current (INa) amplitude and tetrodotoxin, at doses that reduced INa as moderately as dopamine, also inhibited spiking. These results provide the first direct evidence that D1-type dopamine receptor activation can alter mammalian retinal ganglion cell excitability, and demonstrate that dopamine can modulate spikes in these cells by a mechanism different from the pre- and postsynaptic means proposed by previous studies. To our knowledge, our results also provide the first evidence that dopamine receptor activation can reduce excitability without altering the temporal precision of spike firing. PMID:19940196

  14. Serotonin Transporter Knockout Rats Show Improved Strategy Set-Shifting and Reduced Latent Inhibition

    ERIC Educational Resources Information Center

    Nonkes, Lourens J. P.; van de Vondervoort, Ilse I. G. M.; de Leeuw, Mark J. C.; Wijlaars, Linda P.; Maes, Joseph H. R.; Homberg, Judith R.

    2012-01-01

    Behavioral flexibility is a cognitive process depending on prefrontal areas allowing adaptive responses to environmental changes. Serotonin transporter knockout (5-HTT[superscript -/-]) rodents show improved reversal learning in addition to orbitofrontal cortex changes. Another form of behavioral flexibility, extradimensional strategy set-shifting…

  15. Early life versus lifelong oral manganese exposure differently impairs skilled forelimb performance in adult rats.

    PubMed

    Beaudin, Stephane A; Nisam, Sean; Smith, Donald R

    2013-01-01

    Recent studies of children suggest that exposure to elevated manganese (Mn) levels disrupts aspects of motor, cognitive and behavioral functions that are dependent on dopamine brain systems. Although basal ganglia motor functions are well-known targets of adult occupational Mn exposure, the extent of motor function deficits in adults as a result of early life Mn exposure is unknown. Here we used a rodent model early life versus lifelong oral Mn exposure and the Montoya staircase test to determine whether developmental Mn exposure produces long-lasting deficits in sensorimotor performance in adulthood. Long-Evans male neonate rats (n=11/treatment) were exposed daily to oral Mn at levels of 0, 25, or 50mg Mn/kg/d from postnatal day (PND) 1-21 (early life only), or from PND 1-throughout life. Staircase testing began at age PND 120 and lasted 1month to objectively quantify measures of skilled forelimb use in reaching and pellet grasping/retrieval performance. Behavioral reactivity also was rated on each trial. Results revealed that (1) behavioral reactivity scores were significantly greater in the Mn-exposed groups, compared to controls, during the staircase acclimation/training stage, but not the latter testing stages, (2) early life Mn exposure alone caused long-lasting impairments in fine motor control of reaching skills at the higher, but not lower Mn dose, (3) lifelong Mn exposure from drinking water led to widespread impairment in reaching and grasping/retrieval performance in adult rats, with the lower Mn dose group showing the greatest impairment, and (4) lifelong Mn exposure produced similar (higher Mn group) or more severe (lower Mn group) impairments compared to their early life-only Mn exposed counterparts. Collectively, these results substantiate the emerging clinical evidence in children showing associations between environmental Mn exposure and deficits in fine sensorimotor function. They also show that the objective quantification of skilled motor

  16. Methoxychlor induces apoptosis via mitochondria- and FasL-mediated pathways in adult rat testis.

    PubMed

    Vaithinathan, S; Saradha, B; Mathur, P P

    2010-04-29

    In the past few years, there has been much concern about the adverse health effects of environmental contaminants in general and organochlorine in particular. Studies have shown the repro-toxic effects of long-term exposure to methoxychlor, a member of the organochlorine family. However, the insight into the mechanisms of gonadal toxicity induced by methoxychlor is not well known. In the present study we sought to elucidate the mechanism(s) underpinning the gonadal effects within hours of exposure to methoxychlor. Experimental rats were divided into six groups of four each. Animals were orally administered with a single dose of methoxychlor (50mg/kg body weight) and killed at 0, 3, 6, 12, 24, and 72h post-treatment. The levels and time-course of induction of apoptosis-related proteins like cytochorome C, caspase 3 and procaspase 9, Fas-FasL and NF-kappaB were determined to assess sequential induction of apoptosis in the rat testis. DNA damage was assessed by TUNEL assay and flowcytometry. Administration of methoxychlor resulted in a significant increase in the levels of cytosolic cytochrome c and procaspase 9 as early as 6h following exposure. Time-dependent elevations in the levels of Fas, FasL, pro- and cleaved caspase 3 were observed. The DNA damage was measured and showed time-dependent increase in the TUNEL positive cells, and also by flowcytometry of testicular cells. The study demonstrates induction of testicular apoptosis in adult rats following exposure to a single dose of methoxychlor.

  17. Eyeblink classical conditioning and interpositus nucleus activity are disrupted in adult rats exposed to ethanol as neonates.

    PubMed

    Green, John T; Johnson, Timothy B; Goodlett, Charles R; Steinmetz, Joseph E

    2002-01-01

    Neonatal exposure to ethanol in rats, during the period of brain development comparable to that of the human third trimester, produces significant, dose-dependent cell loss in the cerebellum and deficits in coordinated motor performance. These rats are also impaired in eyeblink conditioning as weanlings and as adults. The current study examined single-unit neural activity in the interpositus nucleus of the cerebellum in adults following neonatal binge ethanol exposure. Group Ethanol received alcohol doses of 5.25 g/kg/day on postnatal days 4-9. Group Sham Intubated underwent acute intragastric intubation on postnatal days 4-9 but did not receive any infusions. Group Unintubated Control (from separate litters) did not receive any intubations. When rats were 3-7 mo old, pairs of extracellular microelectrodes were implanted in the region of the interpositus nucleus. Beginning 1 wk later, the rats were given either 100 paired or 190 unpaired trials per day for 10 d followed by 4 d of 100 conditioned stimulus (CS)-alone trials per day. As in our previous study, conditioned response acquisition in Group Ethanol rats was impaired. In addition, by session 5 of paired acquisition, Group Sham Intubated and Group Unintubated Control showed significant increases in interpositus nucleus activity, relative to baseline, in the CS-unconditioned stimulus interval. In contrast, Group Ethanol failed to show significant changes in interpositus nucleus activity until later in training. These results indicate that the disruption in eyeblink conditioning after early exposure to ethanol is reflected in alterations in interpositus nucleus activity.

  18. Muscle mechanical properties of adult and older rats submitted to exercise after immobilization

    PubMed Central

    Kodama, Fábio Yoshikazu; Camargo, Regina Celi Trindade; Job, Aldo Eloizo; Ozaki, Guilherme Akio Tamura; Koike, Tatiana Emy; Camargo Filho, José Carlos Silva

    2012-01-01

    Objectives To describe the effects of immobilization, free remobilization and remobilization by physical exercise about mechanical properties of skeletal muscle of rats of two age groups. Methods 56 Wistar rats divided into two groups according to age, an adult group (five months) and an older group (15 months). These groups were subdivided in: control, immobilized, free remobilized and remobilized by physical exercise. The pelvic limb of rats was immobilized for seven days. The exercise protocol consisted of five swimming sessions, once per day and 25 minutes per session. The gastrocnemius muscle was subjected to tensile tests, and evaluated the properties: load at the maximum limit, stretching at the maximum limit and stiffness. Results The immobilization reduced the values of load at the maximum limit and the remobilization protocols were not sufficient to restore control levels in adult group and older rats. The stretching at the maximum limit differs only in the older group. Conclusions The immobilization reduces the muscle's ability to bear loads and exercise protocol tends to restore the default at control values in adult and older rats. The age factor only interfered in the stretching at the maximum limit, inducing a reduction of this property in the post-immobilization. Level of Evidence II, Investigating the Results of Treatment. PMID:24453606

  19. Restricted feeding facilitates time-place learning in adult rats.

    PubMed

    Lukoyanov, Nikolai V; Pereira, Pedro A; Mesquita, Rui M; Andrade, José P

    2002-08-21

    Many species can acquire time-of-day discrimination when tested in food reinforced place learning tasks. It is believed that this type of learning is dependent upon the ability of animals to consult their internal circadian pacemakers entrained by various environmental zeitgebers, such as light-dark cycles and scheduled restricted feeding. In the present study, we examined, (1) whether rats can acquire time-of-day discrimination in an aversively motivated water maze task wherein an escape platform is located in one position in the morning and in another position in the afternoon; (2) whether time-of-day cues provided by the light- and feeding-entrainable pacemakers may have divergent impacts upon the ability of rats to learn this task. Two groups of rats, both maintained on 12-h light:12-h dark cycle, were used; in one group, animals had free access to food, whereas in the other, they were subjected to a restricted feeding protocol (60% of food consumed by rats fed ad libitum, once daily). Despite the heightened difficulty of the task, food-restricted rats were apparently able to acquire associations between two different platform positions and two different times of day, as indicated by the fact that the percentage of discrimination errors in this group declined progressively, as a function of training, and stabilized at the level of 22+/-9%. In contrast, rats that were fed ad libitum, even after extensive training, failed to perform the task above level of chance. These data indicate that time-place learning is a universal, reward-nonspecific, cognitive phenomenon. They furthermore suggest that the ability of animals to integrate spatial and temporal information can be dependent on the access to timing stimuli provided by the feeding-entrainable circadian system.

  20. Effects of neonatal treatment with the TRPV1 agonist, capsaicin, on adult rat brain and behaviour.

    PubMed

    Newson, Penny N; van den Buuse, Maarten; Martin, Sally; Lynch-Frame, Ann; Chahl, Loris A

    2014-10-01

    Treatment of neonatal rats with the transient receptor potential vanilloid 1 (TRPV1) channel agonist, capsaicin, produces life-long loss of sensory neurons expressing TRPV1 channels. Previously it was shown that rats treated on day 2 of life with capsaicin had behavioural hyperactivity in a novel environment at 5-7 weeks of age and brain changes reminiscent of those found in subjects with schizophrenia. The objective of the present study was to investigate brain and behavioural responses of adult rats treated as neonates with capsaicin. It was found that the brain changes found at 5-7 weeks in rats treated as neonates with capsaicin persisted into adulthood (12 weeks) but were less in older rats (16-18 weeks). Increased prepulse inhibition (PPI) of acoustic startle was found in these rats at 8 and 12 weeks of age rather than the deficit commonly found in animal models of schizophrenia. Subjects with schizophrenia also have reduced flare responses to niacin and methylnicotinate proposed to be mediated by prostaglandin D2 (PGD2). Flare responses are accompanied by cutaneous plasma extravasation. It was found that the cutaneous plasma extravasation responses to methylnicotinate and PGD2 were reduced in capsaicin-treated rats. In conclusion, several neuroanatomical changes observed in capsaicin-treated rats, as well as the reduced cutaneous plasma extravasation responses, indicate that the role of TRPV1 channels in schizophrenia is worthy of investigation.

  1. Prenatal Choline Availability Alters the Context Sensitivity of Pavlovian Conditioning in Adult Rats

    ERIC Educational Resources Information Center

    Lamoureux, Jeffrey A.; Meck, Warren H.; Williams, Christina L.

    2008-01-01

    The effects of prenatal choline availability on Pavlovian conditioning were assessed in adult male rats (3-4 mo). Neither supplementation nor deprivation of prenatal choline affected the acquisition and extinction of simple Pavlovian conditioned excitation, or the acquisition and retardation of conditioned inhibition. However, prenatal choline…

  2. Prenatal exposure to vapors of gasoline-ethanol blends causes few cognitive deficits in adult rats

    EPA Science Inventory

    Developmental exposure to inhaled ethanol-gasoline fuel blends is a potential public health concern. Here we assessed cognitive functions in adult offspring of pregnant rats that were exposed to vapors of gasoline blended with a range of ethanol concentrations, including gasoli...

  3. PREPUBERTAL EXPOSURES TO COMPOUNDS THAT INCREASE PROLACTIN SECRETION IN THE MALE RAT: EFFECTS ON ADULT PROSTATE

    EPA Science Inventory

    Prepubertal exposure to compounds that increase prolactin secretion in the male rat: effects on the adult prostate.

    Stoker TE, Robinette CL, Britt BH, Laws SC, Cooper RL.

    Endocrinology Branch, Reproductive Toxicology Division, National Health and Environmental Effec...

  4. The role of apelin in the modulation of gastric and pancreatic enzymes activity in adult rats.

    PubMed

    Antuschevich, H; Kapica, M; Krawczynska, A; Herman, A; Kato, I; Kuwahara, A; Zabielski, R

    2016-06-01

    Apelin is considered as important gut regulatory peptide ligand of APJ receptor with a potential physiological role in gastrointestinal cytoprotection, regulation of food intake and drinking behavior. Circulating apelin inhibits secretion of pancreatic juice through vagal- cholecystokinin-dependent mechanism and reduces local blood flow. Our study was aimed to determine the effect of fundectomy and intraperitoneal or intragastric administration of apelin-13 on pancreatic and gastric enzymes activities in adult rats. Fundectomy is a surgical removal of stomach fundus - maine site apelin synthesis. Three independent experiments were carried out on Wistar rats. In the first and second experiment apelin-13 was given by intragastric or intraperitoneal way twice a day for 10 days (100 nmol/kg b.w.). Control groups received the physiological saline respectively. In the third experiment the group of rats after fundectomy were used. Fundectomized rats did not receive apelin and the rats from control group were 'sham operated'. At the end of experiment rats were sacrificed and blood from rats was withdrawn for apelin and CCK (cholecystokinin) radioimmunoassay analysis and pancreas and stomach tissues were collected for enzyme activity analyses. Intragastric and intraperitoneal administrations of apelin-13 increased basal plasma CCK level and stimulated gastric and pancreatic enzymes activity in rats. In animals after fundectomy decreased activity of studied enzymes was observed, as well as basal plasma apelin and CCK levels. In conclusion, apelin can effects on CCK release and stimulates some gastric and pancreatic enzymes activity in adult rats while fudectomy suppresses those processes. Changes in the level of pancreatic lipase activity point out that apelin may occurs as a regulator of lipase secretion.

  5. The role of apelin in the modulation of gastric and pancreatic enzymes activity in adult rats.

    PubMed

    Antuschevich, H; Kapica, M; Krawczynska, A; Herman, A; Kato, I; Kuwahara, A; Zabielski, R

    2016-06-01

    Apelin is considered as important gut regulatory peptide ligand of APJ receptor with a potential physiological role in gastrointestinal cytoprotection, regulation of food intake and drinking behavior. Circulating apelin inhibits secretion of pancreatic juice through vagal- cholecystokinin-dependent mechanism and reduces local blood flow. Our study was aimed to determine the effect of fundectomy and intraperitoneal or intragastric administration of apelin-13 on pancreatic and gastric enzymes activities in adult rats. Fundectomy is a surgical removal of stomach fundus - maine site apelin synthesis. Three independent experiments were carried out on Wistar rats. In the first and second experiment apelin-13 was given by intragastric or intraperitoneal way twice a day for 10 days (100 nmol/kg b.w.). Control groups received the physiological saline respectively. In the third experiment the group of rats after fundectomy were used. Fundectomized rats did not receive apelin and the rats from control group were 'sham operated'. At the end of experiment rats were sacrificed and blood from rats was withdrawn for apelin and CCK (cholecystokinin) radioimmunoassay analysis and pancreas and stomach tissues were collected for enzyme activity analyses. Intragastric and intraperitoneal administrations of apelin-13 increased basal plasma CCK level and stimulated gastric and pancreatic enzymes activity in rats. In animals after fundectomy decreased activity of studied enzymes was observed, as well as basal plasma apelin and CCK levels. In conclusion, apelin can effects on CCK release and stimulates some gastric and pancreatic enzymes activity in adult rats while fudectomy suppresses those processes. Changes in the level of pancreatic lipase activity point out that apelin may occurs as a regulator of lipase secretion. PMID:27512001

  6. Effect of Ruta graveolens and Cannabis sativa alcoholic extract on spermatogenesis in the adult wistar male rats

    PubMed Central

    Sailani, M. R.; Moeini, H.

    2007-01-01

    Objective: The present study was undertaken to evaluate the effects of alcohol extracts of Ruta graveolens and Cannabis sativa that were used traditionally in medieval Persian medicine as male contraceptive drugs, on spermatogenesis in the adult male rats. Materials and Methods: Ethanol extracts of these plants were obtained by the maceration method. The male rats were injected intraperitionaly with C. sativa and R. graveolens 5% ethanol extracts at dose of 20 mg/day for 20 consecutive days, respectively. Twenty-four hours after the last treatment, testicular function was assessed by epididymal sperm count. Result: The statistical results showed that the ethanol extracts of these plants reduced the number of sperms significantly (P=0.00) in the treatment groups in comparison to the control group. The results also showed that the group, treated by extract of R. graveolens reduced spermatogenesis more than the group treated by extracts of C. sativa. Conclusion: The present study demonstrated the spermatogenesis reducing properties of the ethanol extracts of R. graveolens and C. sativa in the adult male wistar rats but more studies are necessary to reveal the mechanism of action that is involved in spermatogenesis. PMID:19718326

  7. Juvenile play conditions sexual partner preference in adult female rats.

    PubMed

    Paredes-Ramos, Pedro; Miquel, Marta; Manzo, Jorge; Coria-Avila, Genaro A

    2011-10-24

    Rats can display a conditioned partner preference for individuals that bear an odor previously associated with sexual reward. Herein we tested the possibility that odors associated with the reward induced by social play in prepubescent rats would induce a conditioned partner preference in adulthood. Two groups of 31-day-old, single-housed female rats were formed, and were given daily 30-min periods of social play with scented females. In one group, almond scent was paired with juvenile play during conditioning trials, whereas lemon scent functioned as a novel odor in the final test. The counterbalanced group received the opposite association. At age 42, females were tested for play partner preference with two males, one almond-scented and one lemon-scented. In both groups females displayed a play partner preference only for males scented with the paired odor. They were ovariectomized, hormone-primed, and at age 55 were tested for sexual partner preference with two scented stud males. Females displayed a sexual preference towards males scented with the paired odor as observed with more visits, solicitations, hops and darts, intromissions and ejaculations. These results indicate that olfactory stimuli paired with juvenile play affects later partner choice for play as well as for sex in female rats.

  8. Adversity before Conception Will Affect Adult Progeny in Rats

    ERIC Educational Resources Information Center

    Shachar-Dadon, Alice; Schulkin, Jay; Leshem, Micah

    2009-01-01

    The authors investigated whether adversity in a female, before she conceives, will influence the affective and social behavior of her progeny. Virgin female rats were either undisturbed (controls) or exposed to varied, unpredictable, stressors for 7 days (preconceptual stress [PCS]) and then either mated immediately after the end of the stress…

  9. Dermal penetration of [14C]captan in young and adult rats.

    PubMed

    Fisher, H L; Hall, L L; Sumler, M R; Shah, P V

    1992-07-01

    Age dependence in dermal absorption has been a major concern in risk assessment. Captan, a chloroalkyl thio heterocyclic fungicide, was selected for study of age dependence as representative of this class of pesticides. Dermal penetration of [14C]captan applied at 0.286 mumol/cm2 was determined in young (33-d-old) and adult (82-d-old) female Fischer 344 rats in vivo and by two in vitro methods. Dermal penetration in vivo at 72 h was about 9% of the recovered dose in both young and adult rats. The percentage penetration was found to increase as dosage (0.1, 0.5, 2.7 mumol/cm2) decreased. Two in vitro methods gave variable dermal penetration values compared with in vivo results. A static system yielded twofold higher dermal penetration values compared with in vivo results for both young and adult rats. A flow system yielded higher dermal penetration values in young rats and lower penetration values in adults compared with in vivo results. Concentration in body, kidney, and liver was less in young than in adult rats given the same absorbed dosage. A physiological pharmacokinetic model was developed having a dual compartment for the treated skin and appeared to describe dermal absorption and disposition well. From this model, tissue/blood ratios of captan-derived radioactivity for organs were found to range from 0.35 to 3.4, indicating no large uptake or binding preferences by any organ. This preliminary pharmacokinetic model summarizes the experimental findings and could provide impetus for more complex and realistic models.

  10. Reduced Cerebral Oxygen Content in the DG and SVZ In Situ Promotes Neurogenesis in the Adult Rat Brain In Vivo.

    PubMed

    Zhang, Kuan; Zhou, Yanzhao; Zhao, Tong; Wu, Liying; Huang, Xin; Wu, Kuiwu; Xu, Lun; Li, Dahu; Liu, Shuhong; Zhao, Yongqi; Fan, Ming; Zhu, Lingling

    2015-01-01

    Neurogenesis in the adult brain occurs mainly within two neurogenic structures, the dentate gyrus (DG) of the hippocampus and the sub-ventricular zone (SVZ) of the forebrain. It has been reported that mild hypoxia promoted the proliferation of Neural Stem Cells (NSCs)in vitro. Our previous study further demonstrated that an external hypoxic environment stimulated neurogenesis in the adult rat brain in vivo. However, it remains unknown how external hypoxic environments affect the oxygen content in the brain and result in neurogenesis. Here we use an optical fiber luminescent oxygen sensor to detect the oxygen content in the adult rat brain in situ under normoxia and hypoxia. We found that the distribution of oxygen in cerebral regions is spatiotemporally heterogeneous. The Po2 values in the ventricles (45∼50 Torr) and DG (approximately 10 Torr) were much higher than those of other parts of the brain, such as the cortex and thalamus (approximately 2 Torr). Interestingly, our in vivo studies showed that an external hypoxic environment could change the intrinsic oxygen content in brain tissues, notably reducing oxygen levels in both the DG and SVZ, the major sites of adult neurogenesis. Furthermore, the hypoxic environment also increased the expression of HIF-1α and VEGF, two factors that have been reported to regulate neurogenesis, within the DG and SVZ. Thus, we have demonstrated that reducing the oxygen content of the external environment decreased Po2 levels in the DG and SVZ. This reduced oxygen level in the DG and SVZ might be the main mechanism triggering neurogenesis in the adult brain. More importantly, we speculate that varying oxygen levels may be the physiological basis of the regionally restricted neurogenesis in the adult brain.

  11. The role of the sarcoplasmic reticulum in neonatal uterine smooth muscle: enhanced role compared to adult rat

    PubMed Central

    Noble, Karen; Wray, Susan

    2002-01-01

    Little is known about contractile activity, response to agonists or excitation-contraction coupling in neonatal smooth muscle. We have therefore investigated 10-day rat uterus to better understand these processes, and compared it to adult uterus to elucidate how control of contractility develops. Spontaneous contractions are present in the 10-day neonatal uterus, although they are not as large or as regular as those present in adult tissues. External Ca2+ entry via L-type Ca2+ channels is the sole source of Ca2+ and is essential for the spontaneous activity. The neonatal uterus was responsive to carbachol or prostaglandin F2α application; it showed a marked stimulation and a clear dissociation between the force and Ca2+ changes. Such sensitization was not apparent in adult rat myometrium. The sarcoplasmic reticulum (SR) had more releasable Ca2+ and contributed more to the response to agonists in neonatal compared to adult tissues. Thus, Ca2+ entry as opposed to SR Ca2+ release contributed much less to the uterine response to agonists in the neonatal, compared to adult tissues. Inhibition of the SR by cyclopiazonic acid also caused a more vigorous increase in Ca2+ and contractile activity, particularly frequency, in the neonatal compared to the adult uterus. Taken together these data suggest that: (1) spontaneous activity is already present by day 10, (2) receptor-coupling and excitation-contraction signalling pathways are functional, (3) the SR and Ca2+ sensitization mechanisms play a more prominent role in the neonate, and (4) there is a shift to a greater reliance on Ca2+ entry and excitability with development of the myometrium. PMID:12456834

  12. Effect of prenatal programming and postnatal rearing on glomerular filtration rate in adult rats.

    PubMed

    Lozano, German; Elmaghrabi, Ayah; Salley, Jordan; Siddique, Khurrum; Gattineni, Jyothsna; Baum, Michel

    2015-03-01

    The present study examined whether a prenatal low-protein diet programs a decrease in glomerular filtration rate (GFR) and an increase in systolic blood pressure (BP). In addition, we examined whether altering the postnatal nutritional environment of nursing neonatal rats affected GFR and BP when rats were studied as adults. Pregnant rats were fed a normal (20%) protein diet or a low-protein diet (6%) during the last half of pregnancy until birth, when rats were fed a 20% protein diet. Mature adult rats from the prenatal low-protein group had systolic hypertension and a GFR of 0.38 ± 0.03 versus 0.57 ± 0.05 ml·min(-1)·100 g body wt(-1) in the 20% group (P < 0.01). In cross-fostering experiments, mothers continued on the same prenatal diet until weaning. Prenatal 6% protein rats cross-fostered to a 20% mother on day 1 of life had a GFR of 0.53 ± 0.05 ml·min(-1)·100 g body wt(-1), which was not different than the 20% group cross-fostered to a different 20% mother (0.45 ± 0.04 ml·min(-1)·100 g body wt(-1)). BP in the 6% to 20% group was comparable with the 20% to 20% group. Offspring of rats fed either 20% or 6% protein diets during pregnancy and cross-fostered to a 6% mother had elevated BP but a comparable GFR normalized to body weight as the 20% to 20% control group. Thus, a prenatal low-protein diet causes hypertension and a reduction in GFR in mature adult offspring, which can be modified by postnatal rearing.

  13. Altered differentiation of CNS neural progenitor cells after transplantation into the injured adult rat spinal cord.

    PubMed

    Onifer, S M; Cannon, A B; Whittemore, S R

    1997-01-01

    Denervation of CNS neurons and peripheral organs is a consequence of traumatic SCI. Intraspinal transplantation of embryonic CNS neurons is a potential strategy for reinnervating these targets. Neural progenitor cell lines are being investigated as alternates to embryonic CNS neurons. RN33B is an immortalized neural progenitor cell line derived from embryonic rat raphe nuclei following infection with a retrovirus encoding the temperature-sensitive mutant of SV40 large T-antigen. Transplantation studies have shown that local epigenetic signals in intact or partially neuron-depleted adult rat hippocampal formation or striatum direct RN33B cell differentiation to complex multipolar morphologies resembling endogenous neurons. After transplantation into neuron-depleted regions of the hippocampal formation or striatum, RN33B cells were relatively undifferentiated or differentiated with bipolar morphologies. The present study examines RN33B cell differentiation after transplantation into normal spinal cord and under different lesion conditions. Adult rats underwent either unilateral lesion of lumbar spinal neurons by intraspinal injection of kainic acid or complete transection at the T10 spinal segment. Neonatal rats underwent either unilateral lesion of lumbar motoneurons by sciatic nerve crush or complete transection at the T10 segment. At 2 or 6-7 wk postinjury, lacZ-labeled RN33B cells were transplanted into the lumbar enlargement of injured and age-matched normal rats. At 2 wk posttransplantation, bipolar and some multipolar RN33B cells were found throughout normal rat gray matter. In contrast, only bipolar RN33B cells were seen in gray matter of kainic acid lesioned, sciatic nerve crush, or transection rats. These observations suggest that RN33B cell multipolar morphological differentiation in normal adult spinal cord is mediated by direct cell-cell interaction through surface molecules on endogenous neurons and may be suppressed by molecules released after SCI

  14. Juvenile stress affects anxiety-like behavior and limbic monoamines in adult rats.

    PubMed

    Luo, Xiao-Min; Yuan, San-Na; Guan, Xi-Ting; Xie, Xi; Shao, Feng; Wang, Wei-Wen

    2014-08-01

    Epidemiological evidence suggests that childhood and adolescent maltreatment is a major risk factor for mood disorders in adulthood. However, the mechanisms underlying the manifestation of mental disorders during adulthood are not well understood. Using a recently developed rat model for assessing chronic variable stress (CVS) during early adolescence (juvenility), we investigated the long-term effects of juvenile CVS on emotional and cognitive function and on monoaminergic activities in the limbic areas. During juvenility (postnatal days 27-33), rats in the stress group were exposed to variable stressors every other day for a week. Four weeks later, anhedonia was tested in the sucrose test, anxiety-like behaviors were assessed in the elevated plus-maze (EPM) and open field (OF) tests, and cortically mediated cognitive function was evaluated during an attentional set-shifting task (AST). After the behavioral tests, the rats were decapitated to determine limbic monoamine and metabolite levels. Adult rats stressed during juvenility exhibited higher anxiety-like behaviors, as evidenced by reduced locomotion and rearing behavior in the OF and fewer entries into the open arms in the EPM. There were no differences between the stressed rats and the controls in depressive-like anhedonia during the sucrose preference test or in cognitive function during the AST test in adulthood. In addition, the previously stressed rats exhibited increased dopamine (DA) and decreased 5-HIAA in the medial prefrontal cortex (mPFC) and decreased noradrenaline in the amygdala compared with controls. Furthermore, DA levels in the mPFC were correlated with adult anxious behaviors in the OF. These results suggest that juvenile stress induces long-term changes in the expression of anxiety-like behaviors and limbic monoaminergic activity in adult rats.

  15. Functional Myotube Formation from Adult Rat Satellite Cells in a Defined Serum-free System

    PubMed Central

    McAleer, Christopher W.; Rumsey, John W.; Stancescu, Maria; Hickman, James J.

    2016-01-01

    This manuscript describes the development of a culture system whereby mature contracting myotubes were formed from adult rat derived satellite cells. Satellite cells, extracted from the Tibialis Anterior (TA) of adult rats, were grown in defined serum-free growth and differentiation media, on a non-biological substrate, N-1[3-trimethoxysilyl propyl] diethylenetriamine. Myotubes were evaluated morphologically and immunocytochemically, using MyHC specific antibodies, as well as functionally using patch clamp electrophysiology to measure ion channel activity. Results indicated the establishment of the rapid expression of adult myosin isoforms that contrasts to their slow development in embryonic cultures. This culture system has applications in the understanding and treatment of age related muscle myopathy, muscular dystrophy, and for skeletal muscle engineering by providing a more relevant phenotype for both in vitro and in vivo applications. PMID:25683642

  16. Age-related differences in the sensitivity to opiate-induced perturbations in reproductive endocrinology in the developing and adult male rat.

    PubMed

    Cicero, T J; O'Connor, L; Nock, B; Adams, M L; Miller, B T; Bell, R D; Meyer, E R

    1989-01-01

    The effects of a single morphine pellet (75 mg) implanted in developing male rats at 27 days of age on reproductive endocrine parameters were compared to those found in adult (65-day-old) animals after the same treatment. The pellets were left in place to provide the release of morphine during critical phases of puberty and sexual maturation and to prevent an abrupt withdrawal syndrome upon pellet removal which would confound our results. Developing rats were sacrificed at representative intervals after pellet insertion to assess the development of key indices of reproductive endocrinology; adult rats were sacrificed at the same time intervals to permit an evaluation of age-related differences in the sensitivity to opiate-induced endocrine disturbances. Our results showed that morphine markedly influenced a number of endocrine parameters associated with the maturation of the hypothalamic-pituitary-gonadal axis in developing rats for prolonged periods of time, whereas the effects of the opiate in the adult rat were relatively modest and transient. In the developing rat, serum luteinizing hormone (LH), testosterone, the wet tissue weights of the seminal vesicles and testes and hypothalamic LH-releasing hormone (LHRH) levels were substantially depressed immediately after pellet implantation and these effects persisted for up to 4 weeks when compared to placebo-implanted, age-matched controls. In contrast to these results, adult rats showed only transient effects (less than 1 week) of morphine on certain reproductive endocrine parameters (e.g., serum LH, testosterone and the weights of the seminal vesicles) and no effects on others (e.g., testes weights and hypothalamic LHRH).(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Comparison of apoptosis between adult worms of Schistosoma japonicum from susceptible (BALB/c mice) and less-susceptible (Wistar rats) hosts.

    PubMed

    Wang, Tao; Guo, Xiaoyong; Hong, Yang; Han, Hongxiao; Cao, Xiaodan; Han, Yanhui; Zhang, Min; Wu, Miaoli; Fu, Zhiqiang; Lu, Ke; Li, Hao; Zhao, Zhixin; Lin, Jiaojiao

    2016-10-30

    Schistosomiasis remains a serious public health concern in China. BALB/c mice are susceptible to Schistosoma japonicum infection, whereas the Wistar rats are less susceptible. Apoptosis phenomenon was observed in 42d adult worms of S. japonicum from both rats and mice at the morphologic, DNA, cellular, and gene levels by transmission electron microscopy (TEM), fluorometric terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) analysis, fluorescein isothiocyanate-annexin-V/propidium iodide staining flow cytometry (FCM) analysis, and real-time PCR. The results showed that the apoptotic state in worms from two different susceptible hosts was diverse. Several classical hallmarks of apoptosis, including cell shrinkage, chromatin condensation and lunate marginalization, splitting of the nucleoli, nuclear shrinkage and apoptotic body formation were observed by TEM. TUNEL analysis showed that there were much more apoptosis spots in adult worms from rats than those from mice. Statistical analysis revealed that the degree of apoptosis and percentage of necrotic cells in adult worms from Wistar rats were significantly greater (P<0.01) than those from BALB/c mice by flow cytometry. A total of 15 apoptosis-associated genes including the major components of an intrinsic cell-death pathway were identified from S. japonicum in this study, suggested that a similar apoptosis pathway might occur in S. japonicum. Real-time PCR analyses revealed that the expression levels of most of the tested apoptosis-associated genes, except CASP7, were significantly higher or at the similar level in adult worms from Wistar rats, as compared to those from BALB/c mice. The results obtained in this study collectively demonstrated that differential development of adult S. japonicum in less-susceptible rats and susceptible mice was significantly associated with apoptosis in the worm, and provided valuable information to guide further investigations of the mechanisms governing

  18. Comparison of apoptosis between adult worms of Schistosoma japonicum from susceptible (BALB/c mice) and less-susceptible (Wistar rats) hosts.

    PubMed

    Wang, Tao; Guo, Xiaoyong; Hong, Yang; Han, Hongxiao; Cao, Xiaodan; Han, Yanhui; Zhang, Min; Wu, Miaoli; Fu, Zhiqiang; Lu, Ke; Li, Hao; Zhao, Zhixin; Lin, Jiaojiao

    2016-10-30

    Schistosomiasis remains a serious public health concern in China. BALB/c mice are susceptible to Schistosoma japonicum infection, whereas the Wistar rats are less susceptible. Apoptosis phenomenon was observed in 42d adult worms of S. japonicum from both rats and mice at the morphologic, DNA, cellular, and gene levels by transmission electron microscopy (TEM), fluorometric terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) analysis, fluorescein isothiocyanate-annexin-V/propidium iodide staining flow cytometry (FCM) analysis, and real-time PCR. The results showed that the apoptotic state in worms from two different susceptible hosts was diverse. Several classical hallmarks of apoptosis, including cell shrinkage, chromatin condensation and lunate marginalization, splitting of the nucleoli, nuclear shrinkage and apoptotic body formation were observed by TEM. TUNEL analysis showed that there were much more apoptosis spots in adult worms from rats than those from mice. Statistical analysis revealed that the degree of apoptosis and percentage of necrotic cells in adult worms from Wistar rats were significantly greater (P<0.01) than those from BALB/c mice by flow cytometry. A total of 15 apoptosis-associated genes including the major components of an intrinsic cell-death pathway were identified from S. japonicum in this study, suggested that a similar apoptosis pathway might occur in S. japonicum. Real-time PCR analyses revealed that the expression levels of most of the tested apoptosis-associated genes, except CASP7, were significantly higher or at the similar level in adult worms from Wistar rats, as compared to those from BALB/c mice. The results obtained in this study collectively demonstrated that differential development of adult S. japonicum in less-susceptible rats and susceptible mice was significantly associated with apoptosis in the worm, and provided valuable information to guide further investigations of the mechanisms governing

  19. Characterization of Amino Acid Profile and Enzymatic Activity in Adult Rat Astrocyte Cultures.

    PubMed

    Souza, Débora Guerini; Bellaver, Bruna; Hansel, Gisele; Arús, Bernardo Assein; Bellaver, Gabriela; Longoni, Aline; Kolling, Janaina; Wyse, Angela T S; Souza, Diogo Onofre; Quincozes-Santos, André

    2016-07-01

    Astrocytes are multitasking players in brain complexity, possessing several receptors and mechanisms to detect, participate and modulate neuronal communication. The functionality of astrocytes has been mainly unraveled through the study of primary astrocyte cultures, and recently our research group characterized a model of astrocyte cultures derived from adult Wistar rats. We, herein, aim to characterize other basal functions of these cells to explore the potential of this model for studying the adult brain. To characterize the astrocytic phenotype, we determined the presence of GFAP, GLAST and GLT 1 proteins in cells by immunofluorescence. Next, we determined the concentrations of thirteen amino acids, ATP, ADP, adenosine and calcium in astrocyte cultures, as well as the activities of Na(+)/K(+)-ATPase and acetylcholine esterase. Furthermore, we assessed the presence of the GABA transporter 1 (GAT 1) and cannabinoid receptor 1 (CB 1) in the astrocytes. Cells demonstrated the presence of glutamine, consistent with their role in the glutamate-glutamine cycle, as well as glutamate and D-serine, amino acids classically known to act as gliotransmitters. ATP was produced and released by the cells and ADP was consumed. Calcium levels were in agreement with those reported in the literature, as were the enzymatic activities measured. The presence of GAT 1 was detected, but the presence of CB 1 was not, suggesting a decreased neuroprotective capacity in adult astrocytes under in vitro conditions. Taken together, our results show cellular functionality regarding the astrocytic role in gliotransmission and neurotransmitter management since they are able to produce and release gliotransmitters and to modulate the cholinergic and GABAergic systems. PMID:26915106

  20. Delayed intramuscular human neurotrophin-3 improves recovery in adult and elderly rats after stroke.

    PubMed

    Duricki, Denise A; Hutson, Thomas H; Kathe, Claudia; Soleman, Sara; Gonzalez-Carter, Daniel; Petruska, Jeffrey C; Shine, H David; Chen, Qin; Wood, Tobias C; Bernanos, Michel; Cash, Diana; Williams, Steven C R; Gage, Fred H; Moon, Lawrence D F

    2016-01-01

    There is an urgent need for a therapy that reverses disability after stroke when initiated in a time frame suitable for the majority of new victims. We show here that intramuscular delivery of neurotrophin-3 (NT3, encoded by NTF3) can induce sensorimotor recovery when treatment is initiated 24 h after stroke. Specifically, in two randomized, blinded preclinical trials, we show improved sensory and locomotor function in adult (6 months) and elderly (18 months) rats treated 24 h following cortical ischaemic stroke with human NT3 delivered using a clinically approved serotype of adeno-associated viral vector (AAV1). Importantly, AAV1-hNT3 was given in a clinically-feasible timeframe using a straightforward, targeted route (injections into disabled forelimb muscles). Magnetic resonance imaging and histology showed that recovery was not due to neuroprotection, as expected given the delayed treatment. Rather, treatment caused corticospinal axons from the less affected hemisphere to sprout in the spinal cord. This treatment is the first gene therapy that reverses disability after stroke when administered intramuscularly in an elderly body. Importantly, phase I and II clinical trials by others show that repeated, peripherally administered high doses of recombinant NT3 are safe and well tolerated in humans with other conditions. This paves the way for NT3 as a therapy for stroke.

  1. Delayed intramuscular human neurotrophin-3 improves recovery in adult and elderly rats after stroke

    PubMed Central

    Duricki, Denise A.; Hutson, Thomas H.; Kathe, Claudia; Soleman, Sara; Gonzalez-Carter, Daniel; Petruska, Jeffrey C.; Shine, H. David; Chen, Qin; Wood, Tobias C.; Bernanos, Michel; Cash, Diana; Williams, Steven C. R.; Gage, Fred H.

    2016-01-01

    There is an urgent need for a therapy that reverses disability after stroke when initiated in a time frame suitable for the majority of new victims. We show here that intramuscular delivery of neurotrophin-3 (NT3, encoded by NTF3) can induce sensorimotor recovery when treatment is initiated 24 h after stroke. Specifically, in two randomized, blinded preclinical trials, we show improved sensory and locomotor function in adult (6 months) and elderly (18 months) rats treated 24 h following cortical ischaemic stroke with human NT3 delivered using a clinically approved serotype of adeno-associated viral vector (AAV1). Importantly, AAV1-hNT3 was given in a clinically-feasible timeframe using a straightforward, targeted route (injections into disabled forelimb muscles). Magnetic resonance imaging and histology showed that recovery was not due to neuroprotection, as expected given the delayed treatment. Rather, treatment caused corticospinal axons from the less affected hemisphere to sprout in the spinal cord. This treatment is the first gene therapy that reverses disability after stroke when administered intramuscularly in an elderly body. Importantly, phase I and II clinical trials by others show that repeated, peripherally administered high doses of recombinant NT3 are safe and well tolerated in humans with other conditions. This paves the way for NT3 as a therapy for stroke. PMID:26614754

  2. Effect of seven days of spaceflight on hindlimb muscle protein, RNA and DNA in adult rats

    NASA Technical Reports Server (NTRS)

    Steffen, J. M.; Musacchia, X. J.

    1985-01-01

    Effects of seven days of spaceflight on skeletal muscle (soleus, gastrocnemius, EDL) content of protein, RNA and DNA were determined in adult rats. Whereas total protein contents were reduced in parallel with muscle weights, myofibrillar protein appeared to be more affected. There were no significant changes in absolute DNA contents, but a significant (P less than 0.05) increase in DNA concentration (microgram/milligram) in soleus muscles from flight rats. Absolute RNA contents were significantly (P less than 0.025) decreased in the soleus and gastrocnemius muscles of flight rats, with RNA concentrations reduced 15-30 percent. These results agree with previous ground-based observations on the suspended rat with unloaded hindlimbs and support continued use of this model.

  3. Impairment of male reproduction in adult rats exposed to hydroxyprogesterone caproate in utero

    NASA Astrophysics Data System (ADS)

    Pushpalatha, T.; Ramachandra Reddy, P.; Sreenivasula Reddy, P.

    Hydroxyprogesterone caproate is one of the most effective and widely used drugs for the treatment of uterine bleeding and threatened miscarriage in women. Hydroxyprogesterone caproate was administered to pregnant rats in order to assess the effect of intraperitoneal exposure to supranormal levels of hydroxyprogesterone caproate on the male reproductive potential in the first generation. The cauda epididymal sperm count and motility decreased significantly in rats exposed to hydroxyprogesterone caproate during embryonic development, when compared with control rats. The levels of serum testosterone decreased with an increase in follicle stimulating hormone and luteinizing hormone in adult rats exposed to hydroxyprogesterone caproate during the embryonic stage. It was suggested that the impairment of male reproductive performance could be mediated through the inhibition of testosterone production.

  4. Prenatal exposure to vapors of gasoline-ethanol blends causes few cognitive deficits in adult rats.

    PubMed

    Oshiro, W M; Beasley, T E; McDaniel, K L; Evansky, P A; Martin, S A; Moser, V C; Gilbert, M E; Bushnell, P J

    2015-01-01

    Developmental exposure to inhaled ethanol-gasoline fuel blends is a potential public health concern. Here we assessed cognitive functions in adult offspring of pregnant rats that were exposed to vapors of gasoline blended with a range of ethanol concentrations, including gasoline alone (E0) and gasoline with 15% or 85% ethanol (E15 and E85, respectively). Rat dams were exposed for 6.5h daily to the vapors at concentrations of 0, 3000, 6000, or 9000 ppm in inhalation chambers from gestational day (GD) 9 through 20. Cage controls (offspring of non-exposed dams that remained in the animal facility during these exposures) were also assessed in the E0 experiment, but showed no consistent differences from the offspring of air-exposed controls. Offspring were tested as adults with trace fear conditioning, Morris water maze, or appetitive operant responding. With fear conditioning, no significant effects were observed on cue or context learning. In the water maze, there were no differences in place learning or escaping to a visible platform. However, during the reference memory probe (no platform) male rats exposed prenatally to E85 vapor (6000 and 9000 ppm) failed to show a bias for the target quadrant. Across studies, females (treated and some controls) were less consistent in this measure. Males showed no differences during match-to-place learning (platform moved each day) in any experiment and females showed only transient differences in latency and path length in the E0 experiment. Similarly, no differences were observed in delayed match-to-sample operant performance of E0 males or females; thus this test was not used to evaluate effects of E15 or E85 vapors. During choice reaction time assessments (only males were tested) decision and movement times were unimpaired by any prenatal exposure, while anticipatory responses were increased by vapors of E0 (9000 ppm) and E15 (6000 and 9000 ppm), and the latter group also showed reduced accuracy. E85 vapors did not disrupt

  5. Enhanced sympathetic nerve activity induced by neonatal colon inflammation induces gastric hypersensitivity and anxiety-like behavior in adult rats.

    PubMed

    Winston, John H; Sarna, Sushil K

    2016-07-01

    Gastric hypersensitivity (GHS) and anxiety are prevalent in functional dyspepsia patients; their underlying mechanisms remain unknown largely because of lack of availability of live visceral tissues from human subjects. Recently, we demonstrated in a preclinical model that rats subjected to neonatal colon inflammation show increased basal plasma norepinephrine (NE), which contributes to GHS through the upregulation of nerve growth factor (NGF) expression in the gastric fundus. We tested the hypothesis that neonatal colon inflammation increases anxiety-like behavior and sympathetic nervous system activity, which upregulates the expression of NGF to induce GHS in adult life. Chemical sympathectomy, but not adrenalectomy, suppressed the elevated NGF expression in the fundus muscularis externa and GHS. The measurement of heart rate variability showed a significant increase in the low frequency-to-high frequency ratio in GHS vs. the control rats. Stimulus-evoked release of NE from the fundus muscularis externa strips was significantly greater in GHS than in the control rats. Tyrosine hydroxylase expression was increased in the celiac ganglia of the GHS vs. the control rats. We found an increase in trait but not stress-induced anxiety-like behavior in GHS rats in an elevated plus maze. We concluded that neonatal programming triggered by colon inflammation upregulates tyrosine hydroxylase in the celiac ganglia, which upregulates the release of NE in the gastric fundus muscularis externa. The increase of NE release from the sympathetic nerve terminals concentration dependently upregulates NGF, which proportionately increases the visceromotor response to gastric distention. Neonatal programming concurrently increases anxiety-like behavior in GHS rats. PMID:27151940

  6. Perinatal taurine exposure alters renal potassium excretion mechanisms in adult conscious rats.

    PubMed

    Roysommuti, Sanya; Malila, Pisamai; Lerdweeraphon, Wichaporn; Jirakulsomchok, Dusit; Wyss, J Michael

    2010-08-24

    Perinatal taurine exposure has long-term effects on the arterial pressure and renal function. This study tests its influence on renal potassium excretion in young adult, conscious rats. Female Sprague-Dawley rats were fed normal rat chow and given water alone (C), 3% beta-alanine in water (taurine depletion, TD) or 3% taurine in water (taurine supplementation, TS), either from conception until delivery (fetal period; TDF or TSF) or from delivery until weaning (lactation period; TDL or TSL). In Experiment 1, male offspring were fed normal rat chow and tap water, while in Experiment 2, beta-alanine and taurine were treated from conception until weaning and then female pups were fed normal rat chow and 5% glucose in drinking water (CG, TDG or TSG) or water alone (CW, TDW or TSW). At 7-8 weeks of age, renal potassium excretion was measured at rest and after an acute saline load (5% of body weight) in conscious, restrained rats. Although all male groups displayed similar renal potassium excretion, TSF rats slightly increased fractional potassium excretion at rest but not in response to saline load, whereas TDF did the opposite. Plasma potassium concentration was only slightly altered by the diet manipulations. In female offspring, none of the perinatal treatments significantly altered renal potassium excretion at rest or after saline load. High sugar intake slightly decreased potassium excretion at rest in TDG and TSG, but only the TDG group displayed a decreased response to saline load. The present data indicates that perinatal taurine exposure only mildly influences renal potassium excretion in adult male and female rats.

  7. Relative sensitivity of developmental and immune parameters in juvenile versus adult male rats after exposure to di(2-ethylhexyl) phthalate

    SciTech Connect

    Tonk, Elisa C.M.; Verhoef, Aart; Gremmer, Eric R.; Loveren, Henk van; Piersma, Aldert H.

    2012-04-01

    The developing immune system displays a relatively high sensitivity as compared to both general toxicity parameters and to the adult immune system. In this study we have performed such comparisons using di(2-ethylhexyl) phthalate (DEHP) as a model compound. DEHP is the most abundant phthalate in the environment and perinatal exposure to DEHP has been shown to disrupt male sexual differentiation. In addition, phthalate exposure has been associated with immune dysfunction as evidenced by effects on the expression of allergy. Male wistar rats were dosed with corn oil or DEHP by gavage from postnatal day (PND) 10–50 or PND 50–90 at doses between 1 and 1000 mg/kg/day. Androgen-dependent organ weights showed effects at lower dose levels in juvenile versus adult animals. Immune parameters affected included TDAR parameters in both age groups, NK activity in juvenile animals and TNF-α production by adherent splenocytes in adult animals. Immune parameters were affected at lower dose levels compared to developmental parameters. Overall, more immune parameters were affected in juvenile animals compared to adult animals and effects were observed at lower dose levels. The results of this study show a relatively higher sensitivity of juvenile versus adult rats. Furthermore, they illustrate the relative sensitivity of the developing immune system in juvenile animals as compared to general toxicity and developmental parameters. This study therefore provides further argumentation for performing dedicated developmental immune toxicity testing as a default in regulatory toxicology. -- Highlights: ► In this study we evaluate the relative sensitivities for DEHP induced effects. ► Results of this study demonstrate the age-dependency of DEHP toxicity. ► Functional immune parameters were more sensitive than structural immune parameters. ► Immune parameters were affected at lower dose levels than developmental parameters. ► Findings demonstrate the susceptibility of the

  8. The effect of methoxychlor on the epididymal antioxidant system of adult rats.

    PubMed

    Latchoumycandane, C; Chitra, K C; Mathur, P P

    2002-01-01

    Methoxychlor is widely used as a pesticide in many countries and has been shown to induce reproductive abnormalities in male rats, causing reduced fertility. The mechanism of action of methoxychlor on the male reproductive system is not clear. In the present study we investigated whether administration of methoxychlor induces oxidative stress in the epididymis and epididymal sperm of adult rats. Methoxychlor (50, 100, or 200 mg/kg body weight/day) was administered orally for 1, 4, or 7 days. The animals were killed using anesthetic ether 24 h after of the last treatment. Epididymal sperm were collected by cutting the epididymis into small pieces in Ham's F-12 medium at 35 degrees C. The body weight and weights of the testis, liver, and kidney did not show any significant changes in the methoxychlor-treated rats. The weight of the epididymis, seminal vesicles, and ventral prostate as well as epididymal sperm counts decreased after 50, 100, or 200 mg/kg/day for 7 days but remained unchanged after shorter courses of treatment. Epididymal sperm motility was decreased in a dose-dependent manner in the animals treated with methoxychlor for 4 or 7 days. The activities of the antioxidant enzymes superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase were decreased while the levels of hydrogen peroxide and lipid peroxidation were increased in the epididymal sperm as well as in the caput, corpus, and cauda epididymis after 4 or 7 days of treatment. The activities of superoxide dismutase decreased while the levels of lipid peroxidation increased in the liver but not in the kidney in all groups. Co-administration of the antioxidant vitamin E (20 mg/kg body weight/ day) to the 200 mg/kg/d methoxychlor-treated rats for 7 days prevented significant changes in the antioxidant systems in the epididymis and epididymal sperm and prevented alterations in sperm counts and motility. The results indicated that methoxychlor induces oxidative stress in the

  9. Hepatoprotective activity of bacoside A against N-nitrosodiethylamine-induced liver toxicity in adult rats.

    PubMed

    Janani, Panneerselvam; Sivakumari, Kanakarajan; Parthasarathy, Chandrakesan

    2009-10-01

    N-Nitrosodiethylamine (DEN) is a notorious carcinogen, present in many environmental factors. DEN induces oxidative stress and cellular injury due to enhanced generation of reactive oxygen species; free radical scavengers protect the membranes from DEN-induced damage. The present study was designed to evaluate the protective effect of bacoside A (the active principle isolated from Bacopa monniera Linn.) on carcinogen-induced damage in rat liver. Adult male albino rats were pretreated with 15 mg/kg body weight/day of bacoside A orally (for 14 days) and then intoxicated with single necrogenic dose of N-nitrosodiethylamine (200 mg/kg bodyweight, intraperitonially) and maintained for 7 days. The liver weight, lipid peroxidation (LPO), and activity of serum marker enzymes (aspartate transaminases, alanine transaminases, lactate dehydrogenase, alkaline phosphatase, and gamma-glutamyl transpeptidase) were markedly increased in carcinogen-administered rats, whereas the activities of marker enzymes were near normal in bacoside A-pretreated rats. Activities of antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutatione-S-transferase, and reduced glutathione) in liver also decreased in carcinogen-administered rats, which were significantly elevated in bacoside A-pretreated rats. It is concluded that pretreatment of bacoside A prevents the elevation of LPO and activity of serum marker enzymes and maintains the antioxidant system and thus protects the rats from DEN-induced hepatotoxicity.

  10. Advantage of Guaraná (Paullinia cupana Mart.) supplementation on cadmium-induced damages in testis of adult Wistar rats.

    PubMed

    Leite, Rodrigo P; Predes, Fabrícia S; Monteiro, Juliana C; Freitas, Karine M; Wada, Ronaldo S; Dolder, Heidi

    2013-01-01

    Paullinia cupana is an Amazonian bush whose seeds have long been used in folk medicine. However, most of the therapeutic properties attributed to this plant are broad and nonspecific, although an antioxidant activity has been reported.  On the other hand, cadmium is a heavy metal known for increasing free radicals, hence resulting in cellular oxidative damages. This study was designed to evaluate whether Paullinia cupana is able to reduce cadmium-induced morphological impairment in Wistar rat testis. Adult male Wistar rats 110 days old were ip injected with cadmium (1.15 mg/kg BW [body weight]) and subsequently treated with P. cupana during 56 days.  Furthermore, groups receiving either P. cupana extract or cadmium are mentioned. After the treatment period, testis samples were subjected to histological and stereological analyses. Moderate to severe testicular impairments were shown by the animals exposed to cadmium. However, the animals supplemented with P. cupana after cadmium exposure showed a significant decrease in the proportion of damaged seminiferous tubules. Also, P. cupana supplementation was effective in maintaining the number of Leydig cells per testis in the animals exposed to cadmium. In conclusion, P. cupana supplementation was partially efficient in preventing cadmium from damaging the testis of adult Wistar rats. PMID:22659242

  11. Advantage of Guaraná (Paullinia cupana Mart.) supplementation on cadmium-induced damages in testis of adult Wistar rats.

    PubMed

    Leite, Rodrigo P; Predes, Fabrícia S; Monteiro, Juliana C; Freitas, Karine M; Wada, Ronaldo S; Dolder, Heidi

    2013-01-01

    Paullinia cupana is an Amazonian bush whose seeds have long been used in folk medicine. However, most of the therapeutic properties attributed to this plant are broad and nonspecific, although an antioxidant activity has been reported.  On the other hand, cadmium is a heavy metal known for increasing free radicals, hence resulting in cellular oxidative damages. This study was designed to evaluate whether Paullinia cupana is able to reduce cadmium-induced morphological impairment in Wistar rat testis. Adult male Wistar rats 110 days old were ip injected with cadmium (1.15 mg/kg BW [body weight]) and subsequently treated with P. cupana during 56 days.  Furthermore, groups receiving either P. cupana extract or cadmium are mentioned. After the treatment period, testis samples were subjected to histological and stereological analyses. Moderate to severe testicular impairments were shown by the animals exposed to cadmium. However, the animals supplemented with P. cupana after cadmium exposure showed a significant decrease in the proportion of damaged seminiferous tubules. Also, P. cupana supplementation was effective in maintaining the number of Leydig cells per testis in the animals exposed to cadmium. In conclusion, P. cupana supplementation was partially efficient in preventing cadmium from damaging the testis of adult Wistar rats.

  12. Adolescent exposure to methylphenidate impairs serial pattern learning in the serial multiple choice (SMC) task in adult rats.

    PubMed

    Rowan, James D; McCarty, Madison K; Kundey, Shannon M A; Osburn, Crystal D; Renaud, Samantha M; Kelley, Brian M; Matoushek, Amanda Willey; Fountain, Stephen B

    2015-01-01

    The long-term effects of adolescent exposure to methylphenidate (MPD) on adult cognitive capacity are largely unknown. We utilized a serial multiple choice (SMC) task, which is a sequential learning paradigm for studying complex learning, to observe the effects of methylphenidate exposure during adolescence on later serial pattern acquisition during adulthood. Following 20.0mg/kg/day MPD or saline exposure for 5 days/week for 5 weeks during adolescence, male rats were trained to produce a highly structured serial response pattern in an octagonal operant chamber for water reinforcement as adults. During a transfer phase, a violation to the previously-learned pattern structure was introduced as the last element of the sequential pattern. Results indicated that while rats in both groups were able to learn the training and transfer patterns, adolescent exposure to MPD impaired learning for some aspects of pattern learning in the training phase which are learned using discrimination learning or serial position learning. In contrast adolescent exposure to MPD had no effect on other aspects of pattern learning which have been shown to tap into rule learning mechanisms. Additionally, adolescent MPD exposure impaired learning for the violation element in the transfer phase. This indicates a deficit in multi-item learning previously shown to be responsible for violation element learning. Thus, these results clearly show that adolescent MPD produced multiple cognitive impairments in male rats that persisted into adulthood long after MPD exposure ended.

  13. Distinct local circuits between neocortical pyramidal cells and fast-spiking interneurons in young adult rats.

    PubMed

    Angulo, María Cecilia; Staiger, Jochen F; Rossier, Jean; Audinat, Etienne

    2003-02-01

    Connections between layer V pyramidal cells and GABAergic fast-spiking interneurons (pyramidal-FS) were studied by paired recordings combined with morphological analyses in acute neocortical slices from 28- to 52-day-old rats. Pairs of spikes elicited in pyramidal cells at a stimulation rate of 0.2 Hz induced unitary excitatory postsynaptic currents (EPSCs) in FS interneurons that displayed facilitation (48%), depression (38.5%), or neither depression nor facilitation (13.5%). Analyses of the EPSC amplitude distributions indicate that depressing connections always showed multiple functional release sites. On the contrary, facilitating connections consisted either of one or several release sites. At a holding potential of -72 mV, the quantal size (q) and the release probability (p) of facilitating connections with a single release site were -21.9 +/- 7.5 pA and 0.49 +/- 0.19 (SD), respectively. The mean q and the estimated number of release sites (n) at connections showing multiple sites were obtained by decreasing the release probability and did not differ between depressing and facilitating synapses (depressing connections: q = -15.3 +/- 2.5 pA, n = 5.1 +/- 3, facilitating connections: q = -23.9 +/- 9.8 pA, n = 7.8 +/- 5.4). However, the quantal content at facilitating synapses with multiple sites (1.9 +/- 1.5) was significantly different from that at depressing connections (4.1 +/- 3.9). Finally, quantitative morphological analyses revealed that most of the pyramidal cells displaying facilitation can be differentiated from those displaying depression by a more densely branched apical dendritic tree. Therefore two types of morphologically distinct pyramidal cells form excitatory connections with FS interneurons that differ in their short-term plasticity characteristics. Facilitating and depressing connections may provide a differential control of the temporal information processing of FS cells and thus finely regulate the inhibitory effect of these interneurons in

  14. RNA-stable-isotope probing shows utilization of carbon from inulin by specific bacterial populations in the rat large bowel.

    PubMed

    Tannock, Gerald W; Lawley, Blair; Munro, Karen; Sims, Ian M; Lee, Julian; Butts, Christine A; Roy, Nicole

    2014-04-01

    Knowledge of the trophisms that underpin bowel microbiota composition is required in order to understand its complex phylogeny and function. Stable-isotope ((13)C)-labeled inulin was added to the diet of rats on a single occasion in order to detect utilization of inulin-derived substrates by particular members of the cecal microbiota. Cecal digesta from Fibruline-inulin-fed rats was collected prior to (0 h) and at 6, 12, 18 and 24 h following provision of the [(13)C]inulin diet. RNA was extracted from these cecal specimens and fractionated in isopycnic buoyant density gradients in order to detect (13)C-labeled nucleic acid originating in bacterial cells that had metabolized the labeled dietary constituent. RNA extracted from specimens collected after provision of the labeled diet was more dense than 0-h RNA. Sequencing of 16S rRNA genes amplified from cDNA obtained from these fractions showed that Bacteroides uniformis, Blautia glucerasea, Clostridium indolis, and Bifidobacterium animalis were the main users of the (13)C-labeled substrate. Culture-based studies of strains of these bacterial species enabled trophisms associated with inulin and its hydrolysis products to be identified. B. uniformis utilized Fibruline-inulin for growth, whereas the other species used fructo-oligosaccharide and monosaccharides. Thus, RNA-stable-isotope probing (RNA-SIP) provided new information about the use of carbon from inulin in microbiota metabolism.

  15. Prematurely Delivered Rats Show Improved Motor Coordination During Sensory-evoked Motor Responses Compared to Age-matched Controls

    PubMed Central

    Roberto, Megan E.; Brumley, Michele R.

    2014-01-01

    The amount of postnatal experience for perinatal rats was manipulated by delivering pups one day early (postconception day 21; PC21) by cesarean delivery and comparing their motor behavior to age-matched controls on PC22 (the typical day of birth). On PC22, pups were tested on multiple measures of motor coordination: leg extension response (LER), facial wiping, contact righting, and fore- and hindlimb stepping. The LER and facial wiping provided measures of synchronous hind- and forelimb coordination, respectively, and were sensory-evoked. Contact righting also was sensory-evoked and provided a measure of axial coordination. Stepping provided a measure of alternated forelimb and hindlimb coordination and was induced with the serotonin receptor agonist quipazine. Pups that were delivered prematurely and spent an additional day in the postnatal environment showed more bilateral limb coordination during expression of the LER and facial wiping, as well as a more mature righting strategy, compared to controls. These findings suggest that experience around the time of birth shapes motor coordination and the expression of species-typical behavior in the developing rat. PMID:24680729

  16. Coadministration of black seeds and turmeric shows enhanced efficacy in preventing metabolic syndrome in fructose-fed rats.

    PubMed

    Amin, Faridah; Gilani, Anwarul-Hassan; Mehmood, Malik Hassan; Siddiqui, Bina S; Khatoon, Nasima

    2015-02-01

    Among noncommunicable diseases, metabolic syndrome (MS), a cluster of metabolic disorders including obesity, hyperglycemia, hyperlipidemia and hypertension, is highly prevalent in modern society. Its management requires lifestyle modifications and/or the life-long use of multiple medications, hence demanding development of safe alternative remedies. This study was aimed to establish the efficacy of combined use of black seeds and turmeric using fructose-fed rat model of MS. The high-performance liquid chromatographic fingerprints of turmeric and black seeds showed the presence of curcumin and thymoquinone, respectively, as their major constitutes. Different doses of black seeds and turmeric, individually and in combination, were administered to fructose-fed rats for up to 6 weeks representing characteristic features of MS. At 3 weeks of the treatment, black seeds and turmeric lowered (P < 0.01) high blood pressure and low-density lipoprotein cholesterol, respectively, whereas their coadministration reduced (P < 0.01) both high blood pressure and hypertriglyceridemia. At 6 weeks, the coadministration of both herbs, at half the doses of individual herbs, was the most effective (P < 0.001) in preventing hypertension, hyperglycemia, dyslipidemia, hyperinsulinemia, and endothelial dysfunction than the individual herbs. This study demonstrates the therapeutic superiority of the combination of black seeds and turmeric at low doses over individually tested herbs, in improving features of MS.

  17. RNA–Stable-Isotope Probing Shows Utilization of Carbon from Inulin by Specific Bacterial Populations in the Rat Large Bowel

    PubMed Central

    Lawley, Blair; Munro, Karen; Sims, Ian M.; Lee, Julian; Butts, Christine A.; Roy, Nicole

    2014-01-01

    Knowledge of the trophisms that underpin bowel microbiota composition is required in order to understand its complex phylogeny and function. Stable-isotope (13C)-labeled inulin was added to the diet of rats on a single occasion in order to detect utilization of inulin-derived substrates by particular members of the cecal microbiota. Cecal digesta from Fibruline-inulin-fed rats was collected prior to (0 h) and at 6, 12, 18 and 24 h following provision of the [13C]inulin diet. RNA was extracted from these cecal specimens and fractionated in isopycnic buoyant density gradients in order to detect 13C-labeled nucleic acid originating in bacterial cells that had metabolized the labeled dietary constituent. RNA extracted from specimens collected after provision of the labeled diet was more dense than 0-h RNA. Sequencing of 16S rRNA genes amplified from cDNA obtained from these fractions showed that Bacteroides uniformis, Blautia glucerasea, Clostridium indolis, and Bifidobacterium animalis were the main users of the 13C-labeled substrate. Culture-based studies of strains of these bacterial species enabled trophisms associated with inulin and its hydrolysis products to be identified. B. uniformis utilized Fibruline-inulin for growth, whereas the other species used fructo-oligosaccharide and monosaccharides. Thus, RNA–stable-isotope probing (RNA-SIP) provided new information about the use of carbon from inulin in microbiota metabolism. PMID:24487527

  18. Optical coherence tomography reveals in vivo cortical structures of adult rats in response to cerebral ischemia injury

    NASA Astrophysics Data System (ADS)

    Ni, Yi-rong; Guo, Zhou-yi; Shu, So-yun; Bao, Xin-min

    2008-12-01

    Optical coherence tomography(OCT) is a high resolution imaging technique which uses light to directly image living tissue. we investigate the potential use of OCT for structural imaging of the ischemia injury mammalian cerebral cortex. And we examine models of middle cerebral artery occlusion (MCAO) in rats in vivo using OCT. In particular, we show that OCT can perform in vivo detection of cortex and differentiate normal and abnormal cortical anatomy. This OCT system in this study provided an axial resolution of 10~15μ m, the transverse resolution of the system is about 25 μm. OCT can provide cross-sectional images of cortical of adult rats in response to cerebral ischemia injury.We conclude that OCT represents an exciting new approach to visualize, in real-time, pathological changes in the cerebral cortex structures and may offer a new tool for Possible neuroscience clinical applications.

  19. Cross-sensitization between testosterone and cocaine in adolescent and adult rats.

    PubMed

    Engi, Sheila A; Cruz, Fabio C; Crestani, Carlos C; Planeta, Cleopatra S

    2015-11-01

    Cocaine and anabolic-androgenic steroids are substances commonly co-abused. The use of anabolic steroids and cocaine has increased among adolescents. However, few studies investigated the consequences of the interaction between anabolic-androgenic steroids in animals' model of adolescence. We examined the effects of acute and repeated testosterone administration on cocaine-induced locomotor activity in adult and adolescent rats. Rats received ten once-daily subcutaneous (s.c.) injections of testosterone (10mg/kg) or vehicle. Three days after the last testosterone or vehicle injections rats received an intraperitoneal (i.p.) challenge injection of either saline or cocaine (10mg/kg). A different subset of rats was treated with a single injection of testosterone (10mg/kg) or vehicle and three days later was challenged with cocaine (10mg/kg, i.p.) or saline. Immediately after cocaine or saline injections the locomotor activity was recorded during forty minutes. Our results demonstrated that repeated testosterone induced locomotor sensitization to cocaine in adolescent but not adult rats.

  20. Cross-sensitization between testosterone and cocaine in adolescent and adult rats.

    PubMed

    Engi, Sheila A; Cruz, Fabio C; Crestani, Carlos C; Planeta, Cleopatra S

    2015-11-01

    Cocaine and anabolic-androgenic steroids are substances commonly co-abused. The use of anabolic steroids and cocaine has increased among adolescents. However, few studies investigated the consequences of the interaction between anabolic-androgenic steroids in animals' model of adolescence. We examined the effects of acute and repeated testosterone administration on cocaine-induced locomotor activity in adult and adolescent rats. Rats received ten once-daily subcutaneous (s.c.) injections of testosterone (10mg/kg) or vehicle. Three days after the last testosterone or vehicle injections rats received an intraperitoneal (i.p.) challenge injection of either saline or cocaine (10mg/kg). A different subset of rats was treated with a single injection of testosterone (10mg/kg) or vehicle and three days later was challenged with cocaine (10mg/kg, i.p.) or saline. Immediately after cocaine or saline injections the locomotor activity was recorded during forty minutes. Our results demonstrated that repeated testosterone induced locomotor sensitization to cocaine in adolescent but not adult rats. PMID:26150134

  1. Does prenatal methamphetamine exposure affect the drug-seeking behavior of adult male rats?

    PubMed

    Slamberová, Romana; Schutová, Barbora; Hrubá, Lenka; Pometlová, Marie

    2011-10-10

    Methamphetamine (MA) is one of the most frequently used illicit drugs worldwide and also one of the most common drugs abused by pregnant women. Repeated administration of psychostimulants induces behavioral sensitization in response to treatment of the same or related drugs in rodents. The effect of prenatal MA exposure on sensitivity to drugs in adulthood is not yet fully determined. Because our most recent studies demonstrated that prenatal MA (5mg/kg) exposure makes adult rats more sensitive to acute injection of the same drug, we were interested whether the increased sensitivity corresponds with the increased drug-seeking behavior. The aim of the present study was to examine the effect of prenatal MA exposure on drug-seeking behavior of adult male rats tested in the conditioned place preference (CPP). The following psychostimulant drugs were used as a challenge in adulthood: MA (5mg/kg), amphetamine (5mg/kg) and cocaine (10mg/kg). All psychostimulant drugs induced increased drug-seeking behavior in adult male rats. However, while MA and amphetamine-induced increase in drug-seeking behavior did not differ based on the prenatal drug exposure, prenatally MA-exposed rats displayed tolerance effect to cocaine in adulthood. In addition, prenatally MA-exposed rats had decreased weight gain after administration of MA or amphetamine, while the weight of prenatally MA-exposed rats stayed unchanged after cocaine administration. Defecation was increased by all the drugs (MA, amphetamine and cocaine), while only amphetamine increased the tail temperature. In conclusion, our results did not confirm our hypothesis that prenatal MA exposure increases drug-seeking behavior in adulthood in the CPP test.

  2. Transgenerational effects of adolescent nicotine exposure in rats: Evidence for cognitive deficits in adult female offspring.

    PubMed

    Renaud, Samantha M; Fountain, Stephen B

    2016-01-01

    This study investigated whether adolescent nicotine exposure in one generation of rats would impair the cognitive capacity of a subsequent generation. Male and female rats in the parental F0 generation were given twice-daily i.p. injections of either 1.0mg/kg nicotine or an equivalent volume of saline for 35days during adolescence on postnatal days 25-59 (P25-59). After reaching adulthood, male and female nicotine-exposed rats were paired for breeding as were male and female saline control rats. Only female offspring were used in this experiment. Half of the offspring of F0 nicotine-exposed breeders and half of the offspring of F0 saline control rats received twice-daily i.p. injections of 1.0mg/kg nicotine during adolescence on P25-59. The remainder of the rats received twice-daily saline injections for the same period. To evaluate transgenerational effects of nicotine exposure on complex cognitive learning abilities, F1 generation rats were trained to perform a highly structured serial pattern in a serial multiple choice (SMC) task. Beginning on P95, rats in the F1 generation were given either 4days of massed training (20patterns/day) followed by spaced training (10 patterns/day) or only spaced training. Transgenerational effects of adolescent nicotine exposure were observed as greater difficulty in learning a "violation element" of the pattern, which indicated that rats were impaired in the ability to encode and remember multiple sequential elements as compound or configural cues. The results indicated that for rats that received massed training, F1 generation rats with adolescent nicotine exposure whose F0 generation parents also experienced adolescent nicotine exposure showed poorer learning of the violation element than rats that experienced adolescent nicotine exposure only in the F1 generation. Thus, adolescent nicotine exposure in one generation of rats produced a cognitive impairment in the next generation.

  3. Extracellular matrix molecules and synaptic plasticity: immunomapping of intracellular and secreted Reelin in the adult rat brain.

    PubMed

    Ramos-Moreno, Tania; Galazo, Maria J; Porrero, Cesar; Martínez-Cerdeño, Verónica; Clascá, Francisco

    2006-01-01

    Reelin, a large extracellular matrix glycoprotein, is secreted by several neuron populations in the developing and adult rodent brain. Secreted Reelin triggers a complex signaling pathway by binding lipoprotein and integrin membrane receptors in target cells. Reelin signaling regulates migration and dendritic growth in developing neurons, while it can modulate synaptic plasticity in adult neurons. To identify which adult neural circuits can be modulated by Reelin-mediated signaling, we systematically mapped the distribution of Reelin in adult rat brain using sensitive immunolabeling techniques. Results show that the distribution of intracellular and secreted Reelin is both very widespread and specific. Some interneuron and projection neuron populations in the cerebral cortex contain Reelin. Numerous striatal neurons are weakly immunoreactive for Reelin and these cells are preferentially located in striosomes. Some thalamic nuclei contain Reelin-immunoreactive cells. Double-immunolabeling for GABA and Reelin reveals that the Reelin-immunoreactive cells in the visual thalamus are the intrinsic thalamic interneurons. High local concentrations of extracellular Reelin selectively outline several dendrite spine-rich neuropils. Together with previous mRNA data, our observations suggest abundant axoplasmic transport and secretion in pathways such as the retino-collicular tract, the entorhino-hippocampal ('perforant') path, the lateral olfactory tract or the parallel fiber system of the cerebellum. A preferential secretion of Reelin in these neuropils is consistent with reports of rapid, activity-induced structural changes in adult brain circuits.

  4. Regeneration of adult rat spinal cord is promoted by the soluble KDI domain of gamma1 laminin.

    PubMed

    Wiksten, Markus; Väänänen, Antti J; Liebkind, Ron; Liesi, Päivi

    2004-11-01

    Regeneration in the central nervous system (CNS) of adult mammals is hampered by formation of a glial scar and by proteins released from the myelin sheaths of injured neuronal pathways. Our recent data indicate that the KDI (Lys-Asp-Ile) domain of gamma1 laminin neutralizes both glial- and myelin-derived inhibitory signals and promotes survival and neurite outgrowth of cultured human spinal cord neurons. We show that after complete transection of the adult rat spinal cord, animals receiving onsite infusion of the KDI domain via osmotic mini-pumps recover and are able to sustain their body weights and walk with their hindlimbs. Animals treated with placebo suffer from irreversible hindlimb paralysis. Microscopic and molecular analyses of the spinal cords indicate that the KDI domain reduces tissue damage at the lesion site and enables neurite outgrowth through the injured area to effect functional recovery of the initially paralyzed animals. That the KDI domain enhances regeneration of acute spinal cord injuries in the adult rat suggests that it may be used to promote regeneration of spinal cord injuries in humans.

  5. Behavioral recovery and anatomical plasticity in adult rats after cortical lesion and treatment with monoclonal antibody IN-1.

    PubMed

    Emerick, April J; Kartje, Gwendolyn L

    2004-07-01

    We have previously reported that monoclonal antibody (mAb) IN-1 treatment after ischemic infarct in adult rats results in significant recovery of skilled forelimb use. Such recovery was correlated with axonal outgrowth from the intact, opposite motor cortex into deafferented subcortical motor areas. In the present study, we investigated the effects of mAb IN-1 treatment after adult sensorimotor cortex (SMC) aspiration lesion on behavioral recovery and neuroanatomical plasticity in the corticospinal tract. Adult rats underwent unilateral SMC aspiration lesion and treatment with either mAb IN-1 or a control Ab, or no treatment. Animals were then tested over a 6-week period in the skilled forelimb use task and the skilled ladder rung walking task. We found that animals treated with mAb IN-1 after SMC lesion fully recovered the use of forelimb reaching, but showed no improvement in digit grasping as tested in the skilled forelimb use task. The mAb IN-1 treatment group was also significantly improved as compared to control groups in the skilled ladder rung walking test. Furthermore, neuroanatomical tracing revealed a significant increase in the corticospinal projections into the deafferented motor areas of the spinal cord after mAb IN-1 treatment. These results indicate that treatment with mAb IN-1 after cortical aspiration lesion induces remodeling of motor pathways resulting in recovery in only certain behavioral tasks, suggesting that the cause of brain damage influences behavioral recovery after mAb IN-1 treatment. PMID:15196799

  6. Behavioral Effects of Sub-Acute Inhalation of Toluene in Adult Rats

    EPA Science Inventory

    Reports of behavioral effects of repeated inhalation of toluene in rats have Yielded inconsistent fmdings. A recent study from this laboratory (Beasley et al., 2010) observed that after 13 weeks of inhaled toluene ("sub-chronic" exposure scenario), rats showed mild but persiste...

  7. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats

    PubMed Central

    Cury, Diego Pulzatto; Dias, Fernando José; Miglino, Maria Angélica; Watanabe, Ii-sei

    2016-01-01

    Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis. PMID:27078690

  8. Structural and Ultrastructural Characteristics of Bone-Tendon Junction of the Calcaneal Tendon of Adult and Elderly Wistar Rats.

    PubMed

    Cury, Diego Pulzatto; Dias, Fernando José; Miglino, Maria Angélica; Watanabe, Ii-sei

    2016-01-01

    Tendons are transition tissues that transfer the contractile forces generated by the muscles to the bones, allowing movement. The region where the tendon attaches to the bone is called bone-tendon junction or enthesis and may be classified as fibrous or fibrocartilaginous. This study aims to analyze the collagen fibers and the cells present in the bone-tendon junction using light microscopy and ultrastructural techniques as scanning electron microscopy and transmission electron microscopy. Forty male Wistar rats were used in the experiment, being 20 adult rats at 4 months-old and 20 elderly rats at 20 months-old. The hind limbs of the rats were removed, dissected and prepared to light microscopy, transmission electron microscopy and scanning electron microscopy. The aging process showed changes in the collagen fibrils, with a predominance of type III fibers in the elderly group, in addition to a decrease in the amount of the fibrocartilage cells, fewer and shorter cytoplasmic processes and a decreased synthetic capacity due to degradation of the organelles involved in synthesis. PMID:27078690

  9. Prenatal glucocorticoid exposure in rats: programming effects on stress reactivity and cognition in adult offspring.

    PubMed

    Zeng, Yan; Brydges, Nichola M; Wood, Emma R; Drake, Amanda J; Hall, Jeremy

    2015-01-01

    Human epidemiological studies have provided compelling evidence that prenatal exposure to stress is associated with significantly increased risks of developing psychiatric disorders in adulthood. Exposure to excessive maternal glucocorticoids may underlie this fetal programming effect. In the current study, we assessed how prenatal dexamethasone administration during the last week of gestation affects stress reactivity and cognition in adult offspring. Stress reactivity was assessed by evaluating anxiety-like behavior on an elevated plus maze and in an open field. In addition, to characterize the long-term cognitive outcomes of prenatal exposure to glucocorticoids, animals were assessed on two cognitive tasks, a spatial reference memory task with reversal learning and a delayed matching to position (DMTP) task. Our results suggest that prenatal exposure to dexamethasone had no observable effect on anxiety-like behavior, but affected cognition in the adult offspring. Prenatally dexamethasone-exposed animals showed a transient deficit in the spatial reference memory task and a trend to faster acquisition during the reversal-learning phase. Furthermore, prenatally dexamethasone-treated animals also showed faster learning of new platform positions in the DMTP task. These results suggest that fetal overexposure to glucocorticoids programs a phenotype characterized by cognitive flexibility and adaptability to frequent changes in environmental circumstances. This can be viewed as an attempt to increase the fitness of survival in a potentially hazardous postnatal environment, as predicted by intrauterine adversity. Collectively, our data suggest that prenatal exposure to dexamethasone in rats could be used as an animal model for studying some cognitive components of related psychiatric disorders. PMID:26383033

  10. Plasticity in the prefrontal cortex of adult rats

    PubMed Central

    Kolb, Bryan; Gibb, Robbin

    2015-01-01

    We review the plastic changes of the prefrontal cortex of the rat in response to a wide range of experiences including sensory and motor experience, gonadal hormones, psychoactive drugs, learning tasks, stress, social experience, metaplastic experiences, and brain injury. Our focus is on synaptic changes (dendritic morphology and spine density) in pyramidal neurons and the relationship to behavioral changes. The most general conclusion we can reach is that the prefrontal cortex is extremely plastic and that the medial and orbital prefrontal regions frequently respond very differently to the same experience in the same brain and the rules that govern prefrontal plasticity appear to differ for those of other cortical regions. PMID:25691857

  11. The effects of quinapril and atorvastatin on artery structure and function in adult spontaneously hypertensive rats.

    PubMed

    Yang, Lufang; Gao, Yu-Jing; Lee, Robert M K W

    2005-08-22

    We studied the combined treatment effects of quinapril and atorvastatin on blood pressure and structure and function of resistance arteries from adult spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY rats). Apoptotic cells were identified by in situ end labeling using the terminal deoxynucleotide transferase-mediated dUTP nick end labeling method. Vascular structure was measured using a morphometric protocol and confocal microscopy and a pressurized artery system was used to study vascular functions. We found that a combined treatment with quinapril and atorvastatin lowered systolic blood pressure in both adult SHR and WKY rats and decreased medial thickness and volume and the number of smooth muscle cell layers in mesenteric arteries, as well as media-to-lumen ratio in the interlobular arteries from SHR but not in those from WKY rats. The number of apoptotic smooth muscle cells was higher in the mesenteric arteries from control WKY rats than control SHR and treatment increased the number of apoptotic smooth muscle cells in the arteries from both SHR and WKY rats. Treatment with quinapril and atorvastatin reduced ventricular weight in SHR and normalized the augmented contractile responses to norepinephrine but did not alter the contraction to electric field stimulation. Relaxation responses to acetylcholine and sodium nitroprusside were not affected by the treatment. We conclude that a combined treatment with quinapril and atorvastatin lowered blood pressure and improved cardiac and vessel hypertrophy and vessel function. An increase in apoptotic smooth muscle cells may be one of the mechanisms underlying the structural improvement.

  12. Impaired visual memory in rats reared in isolation is reversed by D-cycloserine in the adult rat.

    PubMed

    Strømme Johannesen, Tone; Myhrer, Trond

    2002-02-15

    Previous studies have shown that environmental factors can influence cholinergic and glutamatergic activity in the developing brain, and that the variations in neurochemistry are accompanied by behavioral changes in later life. Rats reared in isolated, social, or enriched environments were tested with a visual discrimination task in adulthood. The results show that saline-treated rats reared in isolation exhibited impaired retention of the discrimination task compared to rats raised in social or enriched environments. However, systemic administration of the NMDA receptor agonist, D-cycloserine (3 mg/kg), restored normal memory function in cognitively impoverished rats. Acquisition of the task was not affected by the rearing conditions. D-Cycloserine is considered to be an efficient cognitive enhancer probably able to compensate for assumed loss of NMDA receptors during isolated rearing. PMID:11864642

  13. Rotenone exerts similar stimulatory effects on H2O2 production by isolated brain mitochondria from young-adult and old rats.

    PubMed

    Michelini, Luiz G B; Figueira, Tiago R; Siqueira-Santos, Edilene S; Castilho, Roger F

    2015-03-01

    Chronic and systemic treatment of rodents with rotenone, a classical inhibitor of mitochondrial respiratory complex I, results in neurochemical, behavioral, and neuropathological features of Parkinson's disease. The aim of the present study was to evaluate whether brain mitochondria from old rats (24 months old) would be more susceptible to rotenone-induced inhibition of oxygen consumption and increased generation of H2O2 than mitochondria from young-adult rats (3-4 months old). Isolated brain mitochondria were incubated in the presence of different rotenone concentrations (5, 10, and 100nM), and oxygen consumption and H2O2 production were measured during respiratory states 3 (ADP-stimulated respiration) and 4 (resting respiration). Respiratory state 3 and citrate synthase activity were significantly lower in mitochondria from old rats. Mitochondria from young-adult and old rats showed similar sensitivity to rotenone-induced inhibition of oxygen consumption. Similarly, H2O2 production rates by both types of mitochondria were dose-dependently stimulated to the same extent by increasing concentrations of rotenone. We conclude that rotenone exerts similar effects on oxygen consumption and H2O2 production by isolated brain mitochondria from young-adult and old rats. Therefore, aging does not increase the mitochondrial H2O2 generation in response to complex I inhibition.

  14. Protein kinase C regulates mood-related behaviors and adult hippocampal cell proliferation in rats.

    PubMed

    Abrial, Erika; Etievant, Adeline; Bétry, Cécile; Scarna, Hélène; Lucas, Guillaume; Haddjeri, Nasser; Lambás-Señas, Laura

    2013-06-01

    The neurobiological mechanisms underlying the pathophysiology and therapeutics of bipolar disorder are still unknown. In recent years, protein kinase C (PKC) has emerged as a potential key player in mania. To further investigate the role of this signaling system in mood regulation, we examined the effects of PKC modulators in behavioral tests modeling several facets of bipolar disorder and in adult hippocampal cell proliferation in rats. Our results showed that a single injection of the PKC inhibitors tamoxifen (80 mg/kg, i.p.) and chelerythrine (3 mg/kg, s.c.) attenuated amphetamine-induced hyperlocomotion and decreased risk-taking behavior, supporting the efficacy of PKC blockade in acute mania. Moreover, chronic exposure to tamoxifen (10 mg/kg/day, i.p., for 14 days) or chelerythrine (0.3 mg/kg/day, s.c., for 14 days) caused depressive-like behavior in the forced swim test, and resulted in a reduction of cell proliferation in the dentate gyrus of the hippocampus. Finally, we showed that, contrary to the PKC inhibitors, the PKC activator phorbol 12-myristate 13-acetate (PMA) enhanced risk-taking behavior and induced an antidepressant-like effect. Taken together, these findings support the involvement of PKC in regulating opposite facets of bipolar disorder, and emphasize a major role for PKC in this disease. PMID:23228462

  15. Diagnostic accuracy of evoked potentials for functional impairment after contusive spinal cord injury in adult rats.

    PubMed

    Thirumala, Parthasarathy; Zhou, James; Krishnan, Rohan; Manem, Nihita; Umredkar, Shreya; Hamilton, D K; Balzer, Jeffrey R; Oudega, Martin

    2016-03-01

    Iatrogenic spinal cord injury (SCI) is a cause of potentially debilitating post-operative neurologic complications. Currently, intra-operative neurophysiological monitoring (IONM) via somatosensory evoked potentials and motor-evoked potentials is used to detect and prevent impending SCI. However, no empirically validated interventions exist to halt the progression of iatrogenic SCI once it is detected. This is in part due to the lack of a suitable translational model that mimics the circumstances surrounding iatrogenic SCI detected via IONM. Here, we evaluate a model of simulated contusive iatrogenic SCI detected via IONM in adult female Sprague-Dawley rats. We show that transient losses of somatosensory evoked potentials responses are 88.24% sensitive (95% confidence interval [CI] 63.53-98.20) and 80% specific (95% CI 51.91-95.43) for significant functional impairment following simulated iatrogenic SCI. Similarly, we show that transient losses in motor-evoked potentials responses are 70.83% sensitive (95% CI 48.91-87.33) and 100% specific (95% CI 62.91-100.00) for significant functional impairment following simulated iatrogenic SCI. These results indicate that our model is a suitable replica of the circumstances surrounding clinical iatrogenic SCI.

  16. Diagnostic accuracy of evoked potentials for functional impairment after contusive spinal cord injury in adult rats.

    PubMed

    Thirumala, Parthasarathy; Zhou, James; Krishnan, Rohan; Manem, Nihita; Umredkar, Shreya; Hamilton, D K; Balzer, Jeffrey R; Oudega, Martin

    2016-03-01

    Iatrogenic spinal cord injury (SCI) is a cause of potentially debilitating post-operative neurologic complications. Currently, intra-operative neurophysiological monitoring (IONM) via somatosensory evoked potentials and motor-evoked potentials is used to detect and prevent impending SCI. However, no empirically validated interventions exist to halt the progression of iatrogenic SCI once it is detected. This is in part due to the lack of a suitable translational model that mimics the circumstances surrounding iatrogenic SCI detected via IONM. Here, we evaluate a model of simulated contusive iatrogenic SCI detected via IONM in adult female Sprague-Dawley rats. We show that transient losses of somatosensory evoked potentials responses are 88.24% sensitive (95% confidence interval [CI] 63.53-98.20) and 80% specific (95% CI 51.91-95.43) for significant functional impairment following simulated iatrogenic SCI. Similarly, we show that transient losses in motor-evoked potentials responses are 70.83% sensitive (95% CI 48.91-87.33) and 100% specific (95% CI 62.91-100.00) for significant functional impairment following simulated iatrogenic SCI. These results indicate that our model is a suitable replica of the circumstances surrounding clinical iatrogenic SCI. PMID:26677784

  17. Regional distribution of neuropeptide processing endopeptidases in adult rat brain.

    PubMed

    Berman, Y L; Rattan, A K; Carr, K; Devi, L

    1994-01-01

    Many peptide hormone and neuropeptide precursors undergo post-translational processing at mono- and/or dibasic residues. An enzymatic activity capable of processing prodynorphin at a monobasic processing site designated 'dynorphin converting enzyme' has been previously reported in rat rain and bovine pituitary. In this study the distribution of dynorphin converting enzyme activity in ten regions of rat brain has been compared with the distribution of subtilisin-like processing enzymes and with the immuno-reactive dynorphin peptides. The distribution of dynorphin converting enzyme activity generally matches the distribution of immuno-reactive dynorphin B-13 in most but not all brain regions. The regions that are known to have a relatively large number of immuno-reactive dynorphin-neurons also contain high levels of dynorphin converting enzyme activity. The distribution of dynorphin converting enzyme activity does not match the distribution of subtilisin-like processing enzyme or carboxypeptidase E activities. Taken together the data support the possibility that the dynorphin converting enzyme is involved in the maturation of dynorphin, as well as other neuropeptides, and peptide hormones.

  18. Muscarinic acetylcholine receptor modulation of mu (mu) opioid receptors in adult rat sphenopalatine ganglion neurons.

    PubMed

    Margas, Wojciech; Mahmoud, Saifeldin; Ruiz-Velasco, Victor

    2010-01-01

    The sphenopalatine ganglion (SPG) neurons represent the parasympathetic branch of the autonomic nervous system involved in controlling cerebral blood flow. In the present study, we examined the coupling mechanism between mu (mu) opioid receptors (MOR) and muscarinic acetylcholine receptors (mAChR) with Ca(2+) channels in acutely dissociated adult rat SPG neurons. Successful MOR activation was recorded in approximately 40-45% of SPG neurons employing the whole cell variant of the patch-clamp technique. In addition, immunofluorescence assays indicated that MOR are not expressed in all SPG neurons while M(2) mAChR staining was evident in all neurons. The concentration-response relationships generated with morphine and [d-Ala2-N-Me-Phe4-Glycol5]-enkephalin (DAMGO) showed IC(50) values of 15.2 and 56.1 nM and maximal Ca(2+) current inhibition of 26.0 and 38.7%, respectively. Activation of MOR or M(2) mAChR with morphine or oxotremorine-methiodide (Oxo-M), respectively, resulted in voltage-dependent inhibition of Ca(2+) currents via coupling with Galpha(i/o) protein subunits. The acute prolonged exposure (10 min) of neurons to morphine or Oxo-M led to the homologous desensitization of MOR and M(2) mAChR, respectively. The prolonged stimulation of M(2) mAChR with Oxo-M resulted in heterologous desensitization of morphine-mediated Ca(2+) current inhibition, and was sensitive to the M(2) mAChR blocker methoctramine. On the other hand, when the neurons were exposed to morphine or DAMGO for 10 min, heterologous desensitization of M(2) mAChR was not observed. These results suggest that in rat SPG neurons activation of M(2) mAChR likely modulates opioid transmission in the brain vasculature to adequately maintain cerebral blood flow. PMID:19889856

  19. Fetal iron deficiency alters the proteome of adult rat hippocampal synaptosomes

    PubMed Central

    Dakoji, Srikanth; Reise, Kathryn H.; Storey, Kathleen K.; Georgieff, Michael K.

    2013-01-01

    Fetal and neonatal iron deficiency results in cognitive impairments in adulthood despite prompt postnatal iron replenishment. To systematically determine whether abnormal expression and localization of proteins that regulate adult synaptic efficacy are involved, we used a quantitative proteomic approach (isobaric tags for relative and absolute quantitation, iTRAQ) and pathway analysis to identify dysregulated proteins in hippocampal synapses of fetal iron deficiency model. Rat pups were made iron deficient (ID) from gestational day 2 through postnatal day (P) 7 by providing pregnant and nursing dams an ID diet (4 ppm Fe) after which they were rescued with an iron-sufficient diet (200 ppm Fe). This paradigm resulted in a 40% loss of brain iron at P15 with complete recovery by P56. Synaptosomes were prepared from hippocampi of the formerly iron-deficient (FID) and always iron-sufficient controls rats at P65 using a sucrose gradient method. Six replicates per group that underwent iTRAQ labeling and LC-MS/MS analysis for protein identification and comparison elucidated 331 differentially expressed proteins. Western analysis was used to confirm findings for selected proteins in the glutamate receptor signaling pathway, which regulates hippocampal synaptic plasticity, a cellular process critical for learning and memory. Bioinformatics were performed using knowledge-based Interactive Pathway Analysis. FID synaptosomes show altered expression of synaptic proteins-mediated cellular signalings, supporting persistent impacts of fetal iron deficiency on synaptic efficacy, which likely cause the cognitive dysfunction and neurobehavioral abnormalities. Importantly, the findings uncover previously unsuspected pathways, including neuronal nitric oxide synthase signaling, identifying additional mechanisms that may contribute to the long-term biobehavioral deficits. PMID:24089371

  20. Protein Restriction during Pregnancy Induces Hypertension in Adult Female Rat Offspring—Influence of Estradiol

    PubMed Central

    Sathishkumar, K; Elkins, Rebekah; Yallampalli, Uma; Yallampalli, Chandra

    2011-01-01

    We previously reported that gestational dietary protein restriction in rats causes gender-related differences in development of offspring's blood pressure (BP) that is more pronounced in the males than females. Since such effects may depend on sex hormones, we investigated the role of estradiol in the development of hypertension in female offspring of protein restricted dams. Female offspring of pregnant rats fed normal (20%) or protein restricted (6%) casein diets throughout pregnancy were kept either, intact, ovariectomized or ovariectomized with estradiol supplementation. BP, estradiol and testosterone levels and vascular estrogen receptor (ER) were examined. BP was significantly higher and plasma estradiol levels were significantly lower by 34% in intact protein restricted female offspring compared to corresponding controls. Further decrease in estradiol levels by ovariectomy exacerbated hypertension in the protein restricted females with an earlier onset and more prominent elevation in BP compared to controls. Estradiol supplementation in ovariectomized protein restricted females significantly reversed ovariectomy-induced hypertension but did not normalize BP to control levels. The hypertensive protein restricted females have reduced vascular ERα expression that was unaffected by ovariectomy or estradiol replacement. In addition, the testosterone levels were significantly higher by 2.4-, 3.4-, and 2.8-fold in intact, ovariectomized and estradiol replaced protein restricted females compared to corresponding controls. Our data show that: 1) hypertension in protein restricted adult female offspring is associated with reduced plasma estradiol levels, 2) estradiol protects and limits the severity of hypertension in protein restricted females and contribute for sexual dimorphism, and 3) Estradiol replacement fails to completely reverse hypertension, which may be related to limited availability of vascular ERα receptors and/or increased circulating testosterone

  1. Rats with minimal hepatic encephalopathy show reduced cGMP-dependent protein kinase activity in hypothalamus correlating with circadian rhythms alterations.

    PubMed

    Felipo, Vicente; Piedrafita, Blanca; Barios, Juan A; Agustí, Ana; Ahabrach, Hanan; Romero-Vives, María; Barrio, Luis C; Rey, Beatriz; Gaztelu, Jose M; Llansola, Marta

    2015-01-01

    Patients with liver cirrhosis show disturbances in sleep and in its circadian rhythms which are an early sign of minimal hepatic encephalopathy (MHE). The mechanisms of these disturbances are poorly understood. Rats with porta-caval shunt (PCS), a model of MHE, show sleep disturbances reproducing those of cirrhotic patients. The aims of this work were to characterize the alterations in circadian rhythms in PCS rats and analyze the underlying mechanisms. To reach these aims, we analyzed in control and PCS rats: (a) daily rhythms of spontaneous and rewarding activity and of temperature, (b) timing of the onset of activity following turning-off the light, (c) synchronization to light after a phase advance and (d) the molecular mechanisms contributing to these alterations in circadian rhythms. PCS rats show altered circadian rhythms of spontaneous and rewarding activities (wheel running). PCS rats show more rest bouts during the active phase, more errors in the onset of motor activity and need less time to re-synchronize after a phase advance than control rats. Circadian rhythm of body temperature is also slightly altered in PCS rats. The internal period length (tau) of circadian rhythm of motor activity is longer in PCS rats. We analyzed some mechanisms by which hypothalamus modulate circadian rhythms. PCS rats show increased content of cGMP in hypothalamus while the activity of cGMP-dependent protein kinase was reduced by 41% compared to control rats. Altered cGMP-PKG pathway in hypothalamus would contribute to altered circadian rhythms and synchronization to light.

  2. Effect of dietary caffeine and theophylline on urinary calcium excretion in the adult rat.

    PubMed

    Whiting, S J; Whitney, H L

    1987-07-01

    The chronic effects of dietary caffeine or theophylline on urinary calcium excretion were investigated in the adult male rat. When caffeine was added at two concentrations, 0.75 and 1.50 g/kg diet, 24-h urinary calcium excretion rose 300 and 450% on d 7, and 200 and 330% on d 14, respectively. There were no changes in the 24-h urinary excretion of phosphate, sulfate, sodium and cAMP nor did urine volume change. The high dose of caffeine was compared to an equimolar dose of theophylline (1.39 g/kg diet) in both Wistar and Sprague-Dawley rats. Urinary calcium excretion in theophylline-treated rats was significantly greater than in caffeine-treated rats on all sampling days and in both strains of rat; the calciuric effect lasted at least 22 d. When rats were given indomethacin (3.3 mg/kg diet) the calciuria induced by caffeine and theophylline was abolished, and sodium excretion in all groups was reduced by 35-50%, but urine volume was unchanged. The calciuria of methylxanthine feeding may result from a prostaglandin-mediated process distinct from diuresis. PMID:3612301

  3. Temporal expression of mutant LRRK2 in adult rats impairs dopamine reuptake.

    PubMed

    Zhou, Hongxia; Huang, Cao; Tong, Jianbin; Hong, Weimin C; Liu, Yong-Jian; Xia, Xu-Gang

    2011-01-01

    Parkinson's disease (PD) results from progressive degeneration of dopaminergic neurons. Most PD cases are sporadic, but some have pathogenic mutation in the individual genes. Mutation of the leucine-rich repeat kinase-2 (LRRK2) gene is associated with familial and sporadic PD, as exemplified by G2019S substitution. While constitutive expression of mutant LRRK2 in transgenic mice fails to induce neuron death, transient expression of the disease gene by viral delivery causes a substantial loss of dopaminergic neurons in mice. To further assess LRRK2 pathogenesis, we created inducible transgenic rats expressing human LRRK2 with G2019S substitution. Temporal overexpression of LRRK2(G2019S) in adult rats impaired dopamine reuptake by dopamine transporter (DAT) and thus enhanced locomotor activity, the phenotypes that were not observed in transgenic rats constitutively expressing the gene throughout life time. Reduced DAT binding activity is an early sign of dopaminergic dysfunction in asymptomatic subjects carrying pathogenic mutation in LRRK2. Our transgenic rats recapitulated the initiation process of dopaminergic dysfunction caused by pathogenic mutation in LRRK2. Inducible transgenic approach uncovered phenotypes that may be obscured by developmental compensation in constitutive transgenic rats. Finding in inducible LRRK2 transgenic rats would guide developing effective strategy in transgenic studies: Inducible expression of transgene may induce greater phenotypes than constitutive gene expression, particularly in rodents with short life time. PMID:21698001

  4. Associative and non-associative blinking in classically conditioned adult rats.

    PubMed

    Lindquist, Derick H; Vogel, Richard W; Steinmetz, Joseph E

    2009-03-01

    Over the last several years, a growing number of investigators have begun using the rat in classical eyeblink conditioning experiments, yet relatively few parametric studies have been done to examine the nature of conditioning in this species. We report here a parametric analysis of classical eyeblink conditioning in the adult rat using two conditioned stimulus (CS) modalities (light or tone) and three interstimulus intervals (ISI; 280, 580, or 880 ms). Rats trained at the shortest ISI generated the highest percentage of conditioned eyeblink responses (CRs) by the end of training. At the two longer ISIs, rats trained with the tone CS produced unusually high CR percentages over the first few acquisition sessions, relative to rats trained with the light CS. Experiment 2 assessed non-associative blink rates in response to presentations of the light or tone, in the absence of the US, at the same ISI durations used in paired conditioning. Significantly more blinks occurred with longer than shorter duration lights or tones. A higher blink rate was also recorded at all three durations during the early tone-alone sessions. The results suggest that early in classical eyeblink conditioning, rats trained with a tone CS may emit a high number of non-associative blinks, thereby inflating the CR frequency reported at this stage of training. PMID:19071146

  5. Micro-CT analysis of myocardial blood supply in young and adult rats

    NASA Astrophysics Data System (ADS)

    Schaefer, Heather M.; Beighley, Patricia E.; Eaker, Diane R.; Vercnocke, Andrew J.; Ritman, Erik L.

    2009-02-01

    This study addresses whether the vasculature grows in proportion to the myocardium as the rat heart develops. The volume of myocardium and coronary vessels were estimated from micro-CT images of the hearts injected with Microfil(R) contrast agent. Young (n=5) and adult (n=5) hearts were scanned, resulting in 3D images comprised of 20μm on-a-side cubic voxels. The myocardial muscle and vessel lumen volumes were measured for all vessels 40 to 320μm in diameter by an erosion and dilation method applied to the binary images in which the contrast in the vessels were assigned "1" and all non-opacified entities were assigned "0". The average total muscle volume increases by 50%, 129.4 to 237.4mm3, from young to adult rats, while the luminal volume increases by 10%, 16.6 to 18.6mm3. The vessel volume is 12% of the total muscle volume in young and 8% in adults. For a given vessel volume, the muscle volume in the young is 82% of the muscle volume in adults. We conclude that as the heart matures, the myocardium grows more rapidly than the vasculature. This may result in greater angles of separation between vessel branches, and the increase in myocardial coronary volume. The ratio suggests either higher blood flow velocity or a lower metabolic rate in adults.

  6. Effect of the antioxidant dibunol on adrenocortical, thyroid, and adenohypopyseal function in adult and old rats

    SciTech Connect

    Gorban', E.N.

    1986-04-01

    This paper studies the effect of dibunol (4-methyl-2,6-di-tert-butylphenol) (D) on the function of the adrenal cortex, thyroid gland, and adenhypophysis, which produces trophic hormones for the other two glands. Experiments were carried out on adult rats. After injection of D concentrations of corticosterone (CS), triodothyronine (T/sub 3/), ACTH, and thyrotrophin (TSH) in the blood plasma and the CS concentration in tssue of the adenohypophysis were determined. It is shown that injection of D caused biphasic changes in the CS concentration in both tissues studied in adult and old animals.

  7. Chronic delta 9-tetrahydrocannabinol during adolescence provokes sex-dependent changes in the emotional profile in adult rats: behavioral and biochemical correlates.

    PubMed

    Rubino, Tiziana; Vigano', Daniela; Realini, Natalia; Guidali, Cinzia; Braida, Daniela; Capurro, Valeria; Castiglioni, Chiara; Cherubino, Francesca; Romualdi, Patrizia; Candeletti, Sanzio; Sala, Mariaelvina; Parolaro, Daniela

    2008-10-01

    Few and often contradictory reports exist on the long-term neurobiological consequences of cannabinoid consumption in adolescents. The endocannabinoid system plays an important role during the different stages of brain development as cannabinoids influence the release and action of different neurotransmitters and promote neurogenesis. This study tested whether long-lasting interference by cannabinoids with the developing endogenous cannabinoid system during adolescence caused persistent behavioral alterations in adult rats. Adolescent female and male rats were treated with increasing doses of Delta(9)-tetrahydrocannabinol (THC) for 11 days (postnatal day (PND) 35-45) and left undisturbed until adulthood (PND 75) when behavioral and biochemical assays were carried out. CB1 receptor level and CB1/G-protein coupling were significantly reduced by THC exposure in the amygdala (Amyg), ventral tegmental area (VTA) and nucleus accumbens (NAc) of female rats, whereas male rats had significant alterations only in the amygdala and hippocampal formation. Neither female nor male rats showed any changes in anxiety responses (elevated plus maze and open-field tests) but female rats presented significant 'behavioral despair' (forced swim test) paralleled by anhedonia (sucrose preference). In contrast, male rats showed no behavioral despair but did present anhedonia. This different behavioral picture was supported by biochemical parameters of depression, namely CREB alteration. Only female rats had low CREB activity in the hippocampal formation and prefrontal cortex and high activity in the NAc paralleled by increases in dynorphin expression. These results suggest that heavy cannabis consumption in adolescence may induce subtle alterations in the emotional circuit in female rats, ending in depressive-like behavior, whereas male rats show altered sensitivity to rewarding stimuli.

  8. New Hippocampal Neurons Are Not Obligatory for Memory Formation; Cyclin D2 Knockout Mice with No Adult Brain Neurogenesis Show Learning

    ERIC Educational Resources Information Center

    Jaholkowski, Piotr; Kiryk, Anna; Jedynak, Paulina; Abdallah, Nada M. Ben; Knapska, Ewelina; Kowalczyk, Anna; Piechal, Agnieszka; Blecharz-Klin, Kamilla; Figiel, Izabela; Lioudyno, Victoria; Widy-Tyszkiewicz, Ewa; Wilczynski, Grzegorz M.; Lipp, Hans-Peter; Kaczmarek, Leszek; Filipkowski, Robert K.

    2009-01-01

    The role of adult brain neurogenesis (generating new neurons) in learning and memory appears to be quite firmly established in spite of some criticism and lack of understanding of what the new neurons serve the brain for. Also, the few experiments showing that blocking adult neurogenesis causes learning deficits used irradiation and various drugs…

  9. Adolescent social defeat disturbs adult aggression-related impulsivity in wild-type rats.

    PubMed

    Coppens, Caroline M; Coolen, Alex; de Boer, Sietse F; Koolhaas, Jaap M

    2014-10-01

    Adolescence is generally considered as a developmental period during which adverse social experiences may have lasting consequences in terms of an increased vulnerability to affective disorders. This study aimed at determining the individual susceptibility to adolescent social stress using a rat model. We used rats of the Wild-type Groningen strain, which are characterized by a broad variation in adult levels of aggression and impulsivity. We hypothesized that experience of social defeat in adolescence results in heightened aggression and impulsivity levels in adulthood. In contrast to our expectation, adolescent social defeat did not lead to a difference in the average adult level of aggression and impulsivity, but the significant correlation between offensive aggression and impulsivity found in control animals was not present in animals defeated during adolescence.

  10. Assessment of the effects of sex and sex hormones on spatial cognition in adult rats using the Barnes maze

    PubMed Central

    Locklear, MN; Kritzer, MF

    2014-01-01

    Although sex differences and hormone effects on spatial cognition are observed in humans and animals, consensus has not been reached regarding exact impact on spatial working or reference memory. Recent studies in rats suggest that stress and/or reward, which are often different in tasks used to assess spatial cognition, can contribute to the inconsistencies in the literature. To minimize the impact of these sex- and sex hormone-sensitive factors, we used the Barnes maze to compare spatial working memory, spatial reference memory and spatial learning strategy in adult male, female, gonadectomized (GDX) male, and GDX male rats supplemented with 17β-estradiol (E) or testosterone propionate (TP). Rats received four acquisition trials, four trials 24 h later, and a single retention trial one week after. Males and females acquired the task during the first four trials and retained the task thereafter. In contrast, GDX rats took longer to acquire the task and showed retention deficits at 1 week. All deficits were attenuated similarly by TP and E. Assessment of search patterns also showed that strategies in the males transitioned from random to spatially focused and eventually direct approaches to the goal. However, this transition was faster in control and GDX-TP than in GDX and GDX-E rats. In contrast, the females almost invariantly followed the maze edge in thigmotactic, serial searches. Thus, while Barnes maze reveals activational, in part estrogenic effects on spatial cognition in males, its amenability to animals' use of multiple strategies may limit its ability to resolve mnemonic differences across sex. PMID:24937438

  11. Effect of gibberellic acid on the quality of sperm and in vitro fertilization outcome in adult male rats.

    PubMed

    Hosseinchi, Mohammadreza; Soltanalinejad, Farhad; Najafi, Gholamreza; Roshangar, Leila

    2013-01-01

    Gibberellic acid (GA3) is a group of plant hormones identified in various plants. The aim of this study was to determine the effects of GA3 on sperm parameters and in vitro fertilization (IVF). Fifty six adult male rats were divided into seven groups as, control, treatment and sham. Following 15, 30 and 45 days of GA3 and methanol alcohol (MA) administration, rats were euthanized and epididymis tail was transferred to human tubular fluid (HTF) medium containing 4 mg mL(-1) bovine serum albumin (BSA) .Total number of sperms, the percentage of live sperms, immature sperms and sperms with damaged chromatin and IVF were examined. The oocytes were obtained from immature rats after the injection of pregnant mare's serum (PMSG) and human chorionic gonadotropin (HCG) hormones. Human tubular fluid was used as the fertilization medium and zygotes transferred to fresh 1-cell rat embryos culture medium (mR1ECM) to reach the blastocyst stage. This study showed that GA3 could decrease the number of total sperms on days 30 and 45 in treated group comparison with the control and sham groups. Additionally, GA3 increased the immature sperms and sperms with damaged chromatin. The percentage of fertilization, two-cell embryos and blastocyst resulting from the treatment group on days 30 and 45 also decreased and showed significant differences with the control and sham groups (p < 0.05). The results obtained from this study indicated that the oral use of GA3 could reduce the fertility in rats by influencing the sperm number and the quality of sperm's chromatins. PMID:25568681

  12. Airborne particles of the california central valley alter the lungs of healthy adult rats.

    PubMed Central

    Smith, Kevin R; Kim, Seongheon; Recendez, Julian J; Teague, Stephen V; Ménache, Margaret G; Grubbs, David E; Sioutas, Constantinos; Pinkerton, Kent E

    2003-01-01

    Epidemiologic studies have shown that airborne particulate matter (PM) with a mass median aerodynamic diameter < 10 microm (PM10) is associated with an increase in respiratory-related disease. However, there is a growing consensus that particles < 2.5 microm (PM2.5), including many in the ultrafine (< 0.1 microm) size range, may elicit greater adverse effects. PM is a complex mixture of organic and inorganic compounds; however, those components or properties responsible for biologic effects on the respiratory system have yet to be determined. During the fall and winter of 2000-2001, healthy adult Sprague-Dawley rats were exposed in six separate experiments to filtered air or combined fine (PM2.5) and ultrafine portions of ambient PM in Fresno, California, enhanced approximately 20-fold above outdoor levels. The intent of these studies was to determine if concentrated fine/ultrafine fractions of PM are cytotoxic and/or proinflammatory in the lungs of healthy adult rats. Exposures were for 4 hr/day for 3 consecutive days. The mean mass concentration of particles ranged from 190 to 847 microg/m3. PM was enriched primarily with ammonium nitrate, organic and elemental carbon, and metals. Viability of cells recovered by bronchoalveolar lavage (BAL) from rats exposed to concentrated PM was significantly decreased during 4 of 6 weeks, compared with rats exposed to filtered air (p< 0.05). Total numbers of BAL cells were increased during 1 week, and neutrophil numbers were increased during 2 weeks. These observations strongly suggest exposure to enhanced concentrations of ambient fine/ultrafine particles in Fresno is associated with mild, but significant, cellular effects in the lungs of healthy adult rats. PMID:12782490

  13. Maternal separation enhances object location memory and prevents exercise-induced MAPK/ERK signalling in adult Sprague–Dawley rats

    PubMed Central

    Bugarith, Kishor; Russell, Vivienne A

    2012-01-01

    Early life stress increases the risk of developing psychopathology accompanied by reduced cognitive function in later life. Maternal separation induces anxiety-like behaviours and is associated with impaired memory. On the other hand, exercise has been shown to diminish anxiety-like behaviours and improve cognitive function. The effects of maternal separation and exercise on anxiety, memory and hippocampal proteins were investigated in male Sprague–Dawley rats. Maternal separation produced anxiety-like behaviours which were reversed by exercise. Maternal separation also enhanced object location memory which was not affected by exercise. Exercise did, however, increase synaptophysin and phospho-extracellular signal-regulated kinase (p-ERK) in the hippocampus of non-separated rats and this effect was not observed in maternally separated rats. These findings show that maternal separation selectively enhanced n memory and prevented activation of the MAPK/ERK signalling pathway in the adult rat hippocampus. PMID:22476924

  14. Maternal separation enhances object location memory and prevents exercise-induced MAPK/ERK signalling in adult Sprague-Dawley rats.

    PubMed

    Makena, Nokuthula; Bugarith, Kishor; Russell, Vivienne A

    2012-09-01

    Early life stress increases the risk of developing psychopathology accompanied by reduced cognitive function in later life. Maternal separation induces anxiety-like behaviours and is associated with impaired memory. On the other hand, exercise has been shown to diminish anxiety-like behaviours and improve cognitive function. The effects of maternal separation and exercise on anxiety, memory and hippocampal proteins were investigated in male Sprague-Dawley rats. Maternal separation produced anxiety-like behaviours which were reversed by exercise. Maternal separation also enhanced object location memory which was not affected by exercise. Exercise did, however, increase synaptophysin and phospho-extracellular signal-regulated kinase (p-ERK) in the hippocampus of non-separated rats and this effect was not observed in maternally separated rats. These findings show that maternal separation selectively enhanced n memory and prevented activation of the MAPK/ERK signalling pathway in the adult rat hippocampus.

  15. The effects of undernutrition on connectivity in the cerebellar cortex of adult rats.

    PubMed Central

    Yucel, F; Warren, M A; Gumusburun, E

    1994-01-01

    The effects of a 30 d period of undernutrition, followed in some animals by nutritional rehabilitation, on neuronal connectivity in adult rat cerebellum were investigated using the disector method. There was no significant difference between well fed (719 +/- 74, mean +/- S.E.) and undernourished (709 +/- 53) synapse-to-neuron ratios in 134-d-old rat cerebellar cortex, nor was there a significant difference in synapse-to-neuron ratios between control animals (941 +/- 71) and previously undernourished rats (813 +/- 42) at 175 d of age. However, the age-related changes were significant (P < 0.05) in the controls, but not in the experimental group. It may be that the period of undernutrition caused subtle changes in the rehabilitating group which reduced the capacity for growth seen in well fed, matched control animals. PMID:8157493

  16. Altered hypothalamic-pituitary function in the adult female rat with streptozotocin-induced diabetes.

    PubMed

    Spindler-Vomachka, M; Johnson, D C

    1985-01-01

    Infertility associated with anovulation and loss of regular oestrous cyclicity is a consequence of diabetes mellitus in the rat. In an attempt to define loci of altered function, studies were undertaken to examine various aspects of hypothalamic-pituitary function in rats treated with streptozotocin. Medial basal hypothalamic fragments from adult female diabetic rats contained the same amount of gonadotrophin-releasing hormone but, with depolarization, released slightly but insignificantly (p greater than 0.05) more than did those from control animals. Furthermore, release of luteinizing hormone from pituitaries exposed to hypothalamic gonadotrophin-releasing hormone was not altered by diabetes. Removal of the negative feedback effect of gonadal steroids upon the hypothalamic-pituitary axis produced an increase in luteinizing hormone and follicle stimulating hormone concentrations in the serum of normal rats within 6h (p less than 0.05), whereas 24h were required for similar increases in diabetic rats. However, the same concentrations of gonadotrophins were found in diabetic and control animals 120 h after ovariectomy. The inhibitory action of oestradiol benzoate on the secretion of gonadotrophins was more pronounced in ovariectomized diabetic than in control rats. A 74% depression in serum luteinizing hormone (p less than 0.01) was produced by 0.5 microgram oestradiol benzoate per day in diabetic rats, while 5 micrograms was required in control animals. Similar reductions in follicle stimulating hormone concentrations (50%, p less than 0.05) were obtained by injecting 5 micrograms of the oestrogen into diabetic or 50 micrograms into control rats. Increases in serum prolactin were greater in the control animals however.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Sex-dependent effects of maternal deprivation and adolescent cannabinoid treatment on adult rat behaviour.

    PubMed

    Llorente-Berzal, Alvaro; Fuentes, Sílvia; Gagliano, Humberto; López-Gallardo, Meritxell; Armario, Antonio; Viveros, María-Paz; Nadal, Roser

    2011-10-01

    Early life experiences such as maternal deprivation (MD) exert long-lasting changes in adult behaviour and reactivity to stressors. Adolescent exposure to cannabinoids is a predisposing factor in developing certain psychiatric disorders. Therefore, the combination of the two factors could exacerbate the negative consequences of each factor when evaluated at adulthood. The objective of this study was to investigate the long-term effects of early MD [24 hours at postnatal day (PND) 9] and/or an adolescent chronic treatment with the cannabinoid agonist CP-55,940 (0.4 mg/kg, PND 28-42) on diverse behavioural and physiological responses of adult male and female Wistar rats. We tested them in the prepulse inhibition (PPI) of the startle response and analysed their exploratory activity (holeboard) and anxiety (elevated plus maze, EPM). In addition, we evaluated their adrenocortical reactivity in response to stress and plasma leptin levels. Maternal behaviour was measured before and after deprivation. MD induced a transient increase of maternal behaviour on reuniting. In adulthood, maternally deprived males showed anxiolytic-like behaviour (or increased risk-taking behaviour) in the EPM. Adolescent exposure to the cannabinoid agonist induced an impairment of the PPI in females and increased adrenocortical responsiveness to the PPI test in males. Both, MD and adolescent cannabinoid exposure also induced sex-dependent changes in plasma leptin levels and body weights. The present results indicate that early MD and adolescent cannabinoid exposure exerted distinct sex-dependent long-term behavioural and physiological modifications that could predispose to the development of certain neuropsychiatric disorders, though no synergistic effects were found.

  18. Reproductive toxicity of a single dose of 1,3-dinitrobenzene in two ages of young adult male rats

    EPA Science Inventory

    These studies evaluated the reproductive response and the possible influence of testicular maturation on the reproductive parameters, in male rats treated with 1,3-dinitrobenzene (m-DNB). Young adult male rats (75 or 105 days of age) were given a single oral dose of 0, 8, 16, 24,...

  19. Neonatal Maternal Separation Augments Carotid Body Response to Hypoxia in Adult Males but Not Female Rats

    PubMed Central

    Soliz, Jorge; Tam, Rose; Kinkead, Richard

    2016-01-01

    Perinatal exposure to adverse experiences disrupts brain development, including the brainstem network that regulates breathing. At adulthood, rats previously subjected to stress (in the form of neonatal maternal separation; NMS) display features reported in patients suffering from sleep disordered breathing, including an increased hypoxic ventilatory response and hypertension. This effect is also sex-specific (males only). Based on these observations, we hypothesized that NMS augments the carotid body's O2-chemosensitivity. Using an isolated and perfused ex vivo carotid body preparation from adult rats we compared carotid sinus nerve (CSN) responses to hypoxia and hypercapnia in carotid bodies harvested from adult rats that either experienced control conditions (no experimental manipulation) or were subjected to NMS (3 h/day from postnatal days 3 to 12). In males, the CSN response to hypoxia measured in preparations from NMS males was 1.5 fold higher than controls. In control rats, the female's response was similar to that of males; however, the increase in CSN activity measured in NMS females was 3.0 times lower than controls. The CSN response to hypercapnia was not influenced by stress or sex. We conclude that NMS is sufficient to have persistent and sex-specific effects on the carotid body's response to hypoxia. Because NMS also has sex-specific effects on the neuroendocrine response to stress, we propose that carotid body function is influenced by stress hormones. This, in turn, leads to a predisposition toward cardio-respiratory disorders. PMID:27729873

  20. 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.

  1. Hyperforin alleviates mood deficits of adult rats suffered from early separation.

    PubMed

    Zhu, Minghui; Liu, Chunhua; Qin, Xuan; Yang, Zhuo

    2015-11-01

    In this study, we aimed to explore the effect of hyperforin (Hyp) on adult rats suffered from early separation. Wistar infant rats were randomly divided into three groups: control group (CON), early separation from parents group (ESP), and early separation from parents+treatment with 3mg/kg/day Hyp group (ESP+Hyp). Postnatal rats of ESP group and ESP+Hyp group were separated from their mothers for 6h every day on the 14th day after birth, and this separation lasted for 3 weeks, while rats of CON group had no separation. Hyperforin was intragastric administrated on the 21th day after birth, and lasted for 2 weeks in ESP+Hyp group. After separation, adult rats were evaluated by using the open field test (OFT), novelty suppressed feeding test (NSF) and forced swimming test (FST). In OFT, time spent in central grids was much shorter in ESP group compared with that of CON group. After treatment with hyperforin, time spent in central area was much longer compared with that of ESP group. In NSF, the feeding latency of ESP group was much longer than that of CON group. After treatment with hyperforin, the feeding latency was shorter compared with that of ESP group. In FST, score of ESP group was markedly higher than that of CON group. Interestingly, the score was obviously lower in ESP+Hyp group than that of ESP group. In conclusion, these results suggest that hyperforin is able to alleviate anxiety and remit depression in ESP rats. PMID:26420027

  2. A new protocol for cultivation of predegenerated adult rat Schwann cells.

    PubMed

    Pietrucha-Dutczakv, Marita; Marcol, Wiesław; Francuz, Tomasz; Gołka, Dariusz; Lewin-Kowalik, Joanna

    2014-09-01

    The purpose of this study was to optimize the methodology of cultivation of predegenerated Schwann cells (SCs). SCs were isolated from 7-day-predegenerated sciatic nerves of adult rats. We applied commercially available culture medium for cultivation of endothelial cells endothelial cell culture medium (EBM-2) instead of Dulbecco's Modified Eagle's Medium commonly used to culture adult Schwann cells. Additionally, cell culture medium was supplemented with factors specifically supporting SCs growth as: bovine pituitary extract (5 μg/ml), heregulin (40 ng/ml) and insulin (2.5 ng/ml). Similarly to the reports of others authors, we did not observe any beneficial effects of Forskolin application, so we didn't supplement our medium with it. Cell culture purity was determined by counting the ratio of GFAP, N-Cadherin and NGFR p75-positive cells to total number of cells. About 94-97 % of cells were confirmed as Schwann cells. As a result, we obtained sufficient number and purity of Schwann cells to be applied in different experimental models in rats. EBM-2 medium coated with fibronectin was the best for cultivation of adult rat Schwann cells.

  3. Effects of enriched housing on functional recovery after spinal cord contusive injury in the adult rat.

    PubMed

    Lankhorst, A J; ter Laak, M P; van Laar, T J; van Meeteren, N L; de Groot, J C; Schrama, L H; Hamers, F P; Gispen, W H

    2001-02-01

    To date, most research performed in the area of spinal cord injury focuses on treatments designed to either prevent spreading lesion (secondary injury) or to enhance outgrowth of long descending and ascending fiber tracts around or through the lesion. In the last decade, however, several authors have shown that it is possible to enhance locomotor function after spinal cord injury in both animals and patients using specific training paradigms. As a first step towards combining such training paradigms with pharmacotherapy, we evaluated recovery of function in adult rats sustaining a spinal cord contusion injury (MASCIS device, 12.5 mm at T8), either housed in an enriched environment or in standard cages (n = 15 in both groups). The animals in the enriched environment were stimulated to increase their locomotor activity by placing water and food on opposite sides of the cage. As extra stimuli, a running wheel and several other objects were added to the cage. We show that exposure to the enriched environment improves gross and fine locomotor recovery as measured by the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale, the BBB subscale, the Gridwalk, and the Thoracolumbar height test. However, no group differences were found on our electrophysiological parameters nor on the amount of spared white matter. These data justify further studies on enriched housing and more controlled exercise training, with their use as potential additive to pharmacological intervention. PMID:11229712

  4. Effect of prenatal ethanol exposure on sexual motivation in adult rats.

    PubMed

    Ávila, Mara Aparecida P; Marthos, Gabriela Cristina P; Oliveira, Liliane Gibram M; Figueiredo, Eduardo Costa; Giusti-Paiva, Alexandre; Vilela, Fabiana Cardoso

    2016-08-01

    Maternal alcohol use during pregnancy adversely affects prenatal and postnatal growth and increases the risk of behavioral deficits. The aim of the present study was to evaluate the effect of prenatal exposure to a moderate dose of alcohol on sexual motivation during adulthood. Rats were prenatally exposed to ethanol by feeding pregnant dams a liquid diet containing 25% ethanol-derived calories on days 6 through 19 of gestation. The controls consisted of pair-fed dams (receiving an isocaloric liquid diet containing 0% ethanol-derived calories) and dams with ad libitum access to a liquid control diet. The sexual motivation of offspring was evaluated during adulthood. The results revealed that the male and female pups of dams treated with alcohol exhibited reduced weight gain, which persisted until adulthood. Both male and female adult animals from dams that were exposed to alcohol showed a reduction in the preference score in the sexual motivation test. Taken together, these results provide evidence of the damaging effects of prenatal alcohol exposure on sexual motivation responses in adulthood. PMID:27565750

  5. Brain Pathology in Adult Rats Treated With Domoic Acid.

    PubMed

    Vieira, A C; Alemañ, N; Cifuentes, J M; Bermúdez, R; Peña, M López; Botana, L M

    2015-11-01

    Domoic acid (DA) is a neurotoxin reported to produce damage to the hippocampus, which plays an important role in memory. The authors inoculated rats intraperitoneally with an effective toxic dose of DA to study the distribution of the toxin in major internal organs by using immunohistochemistry, as well as to evaluate the induced pathology by means of histopathologic and immunohistochemical methods at different time points after toxin administration (6, 10, and 24 hours; 5 and 54 days). DA was detected by immunohistochemistry exclusively in pyramidal neurons of the hippocampus at 6 and 10 hours after dosing. Lesions induced by DA were prominent at 5 days following treatment in selected regions of the brain: hippocampus, amygdala, piriform and perirhinal cortices, olfactory tubercle, septal nuclei, and thalamus. The authors found 2 types of lesions: delayed death of selective neurons and large areas of necrosis, both accompanied by astrocytosis and microgliosis. At 54 days after DA exposure, the pathology was characterized by still-distinguishable dying neurons, calcified lesions in the thalamus, persistent astrocytosis, and pronounced microgliosis. The expression of nitric oxide synthases suggests a role for nitric oxide in the pathogenesis of neuronal degeneration and chronic inflammation induced by DA in the brain.

  6. CYTOPLASMIC INCLUSIONS RESEMBLING NUCLEOLI IN SYMPATHETIC NEURONS OF ADULT RATS

    PubMed Central

    Grillo, Mary A.

    1970-01-01

    A distinctive cytoplasmic inclusion consisting of a convoluted network of electron-opaque strands embedded in a less dense matrix was identified in the neurons, but not in the supporting cells, of rat sympathetic ganglia. This ball-like structure, designated "nematosome," measures ∼ 0.9 µ and lacks a limiting membrane. Its strands (diameter = 400–600 A) appear to be made of an entanglement of tightly packed filaments and particles ∼ 25–50 A thick. Cytochemical studies carried out with the light microscope suggest the presence of nonhistone proteins and some RNA. Usually only one such structure is present in a cell, and it appears to occur in most ganglion cells. Although they can be seen anywhere in the cell body, nematosomes are typically located in the perinuclear cytoplasm, where they are often associated with smooth-surfaced and coated vesicles. In fine structure and stainability, they bear a resemblance to the fibrous component of the nucleolus. Subsynaptic formations, which are a special feature of some of the synapses in sympathetic ganglia, appear similar to the threadlike elements in the nematosomes. The possibility that these three structures—nucleolus, nematosome, and subsynaptic formation—may be interrelated in origin and function is discussed. PMID:5458990

  7. Effects of NaCl and sultopride on striatal [(3)H]spiperone binding in neonatal, adult and senescent rats.

    PubMed

    Makihata, J; Nomura, Y

    1984-01-01

    Effects of NaCl, (+)-and (-)-sultopride on striatal [(3)H]spiperone binding was investigated in 7-day, 70-day and 2-year-old rats. The amount of specific [(3)H]spiperone binding was the highest at 70 days and the value at adult stage was significantly (P < 0.001) higher than those at 7 days and 2 years. NaCl (100 mM) significantly increased [(3)H]spiperone binding in neonatal (P < 0.01), adult (P < 0.05) and senescent (P < 0.05) animals. Scatchard analysis showed that the Bmax of low-affinity [(3)H]spiperone binding was significantly elevated by 100 mM NaCl compared to the value in control of adult animals. More potent inhibition of (-)-sultopride for [(3)H]spiperone binding than that of the (+)-enantiomer at adult stage was also observed at neonatal and senescent stages. NaCl (100 mM) significantly enhanced inhibitory activities of (+)- and (-)-sultopride at every stage. It is suggested that stabilizing effect of Na(+) on dopamine (DA) receptor complexes and increasing effect of Na(+) on binding affinity of benzamide to DA2 receptors keep functions through development and aging.

  8. Activation of GPER-1 Estradiol Receptor Downregulates Production of Testosterone in Isolated Rat Leydig Cells and Adult Human Testis

    PubMed Central

    Vaucher, Laurent; Funaro, Michael G.; Mehta, Akanksha; Mielnik, Anna; Bolyakov, Alexander; Prossnitz, Eric R.; Schlegel, Peter N.; Paduch, Darius A.

    2014-01-01

    Purpose Estradiol (E2) modulates testicular functions including steroidogenesis, but the mechanisms of E2 signaling in human testis are poorly understood. GPER-1 (GPR30), a G protein-coupled membrane receptor, mediates rapid genomic and non-genomic response to estrogens. The aim of this study was to evaluate GPER-1 expression in the testis, and its role in estradiol dependent regulation of steroidogenesis in isolated rat Leydig cells and human testis. Materials and Methods Isolated Leydig cells (LC) from adult rats and human testicular tissue were used in this study. Expression and localization studies of GPER-1 were performed with qRT-PCR, immunofluorescence, immunohistochemistry and Western Blot. Luteinizing Hormone (LH) -stimulated, isolated LC were incubated with estradiol, G-1 (GPER-1-selective agonist), and estrogen receptor antagonist ICI 182,780. Testosterone production was measured with radioimmunoassay. LC viability after incubation with G-1 was measured using 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt (MTS) assay. Results GPER-1 mRNA is abundantly expressed in rat LC and human testis. Co-localization experiments showed high expression levels of GPER-1 protein in LC. E2-dependent activation of GPER-1 lowers testosterone production in isolated rats LCs and in human testis, with statistically and clinically significant drops in testosterone production by 20–30% as compared to estradiol-naïve LC. The exposure to G-1 does not affect viability of isolated LCs. Conclusions Our results indicate that activation of GPER-1 lowers testosterone levels in the rat and human testis. The expression of GPER-1 in human testis, which lack ERα, makes it an exciting target for developing new agents affecting testosterone production in men. PMID:24736568

  9. Objective measures of motor dysfunction after compression spinal cord injury in adult rats: correlations with locomotor rating scores.

    PubMed

    Semler, Joerg; Wellmann, Katharina; Wirth, Felicitas; Stein, Gregor; Angelova, Srebrina; Ashrafi, Mahak; Schempf, Greta; Ankerne, Janina; Ozsoy, Ozlem; Ozsoy, Umut; Schönau, Eckhard; Angelov, Doychin N; Irintchev, Andrey

    2011-07-01

    Precise assessment of motor deficits after traumatic spinal cord injury (SCI) in rodents is crucial for understanding the mechanisms of functional recovery and testing therapeutic approaches. Here we analyzed the applicability to a rat SCI model of an objective approach, the single-frame motion analysis, created and used for functional analysis in mice. Adult female Wistar rats were subjected to graded compression of the spinal cord. Recovery of locomotion was analyzed using video recordings of beam walking and inclined ladder climbing. Three out of four parameters used in mice appeared suitable: the foot-stepping angle (FSA) and the rump-height index (RHI), measured during beam walking, and for estimating paw placement and body weight support, respectively, and the number of correct ladder steps (CLS), assessing skilled limb movements. These parameters, similar to the Basso, Beattie, and Bresnahan (BBB) locomotor rating scores, correlated with lesion volume and showed significant differences between moderately and severely injured rats at 1-9 weeks after SCI. The beam parameters, but not CLS, correlated well with the BBB scores within ranges of poor and good locomotor abilities. FSA co-varied with RHI only in the severely impaired rats, while RHI and CLS were barely correlated. Our findings suggest that the numerical parameters estimate, as intended by design, predominantly different aspects of locomotion. The use of these objective measures combined with BBB rating provides a time- and cost-efficient opportunity for versatile and reliable functional evaluations in both severely and moderately impaired rats, combining clinical assessment with precise numerical measures. PMID:21428717

  10. Effect of restraint and copper deficiency on blood pressure and mortality of adult rats

    SciTech Connect

    Klevay, L.M.; Halas, E.S. )

    1989-02-01

    The etiology of most hypertension is unknown; stress is thought to elevate blood pressure. Male, weanling Sprague-Dawley rats were fed a purified diet plus a drinking solution containing 10{mu}g Zn and 2{mu}g Cu/ml (acetate sulfate, respectively). Systolic blood pressure was measured without anesthesia. After being matched by mean weight (280g) and blood pressure into 4 groups of 15, groups 1 and 2 received a drinking solution without copper. After 24 days rats in groups 2 and 4 were restrained for 45 min. daily (A.M.) for 23 days in a small plastic cage (19{times}6{times}6 cm). Final pressures were affected both by stress and dietary Cu: group 1, 119; group 2, 131; group 3, 114; group 4, 123 mm Hg. One rat in each of groups 1, 3, 4 and 10 rats in group 2, died. Among these latter hemorrhage was prominent, blood being found in bladder (2), gut (2), peritoneum (2) and scrotum (1). Copper deficiency decreased cooper in both adrenal gland and liver by 58% and in heart by 29% restraint was without effect. Cardiac sodium was increased 6% only by deficiency. Results confirm the hypertensive effect of copper deficiency in adult rats and reveal that the stress of restraint increases blood pressure. Copper deficiency plus stress is harmful.

  11. γ/δ Cells in Fetal, Neonatal, and Adult Rat Lymphoid Organs

    PubMed Central

    Kühnlein, P.; Vicente, A.; Varas, A.; Hünig, T.

    1995-01-01

    In the present study, we have analyzed the appearance and maturation of γ/δ T cells, recognized with a new mAb V65, in the central and peripheral lymphoid organs of fetal, neonatal, and adult Wistar rats. Cytofluorometrical analysis demonstrated the first V65+ γ/δ T cells in the thymus of 16-17-day embryonic rats, although by immunohistology, they were identified only in 19-day rat embryos in both the cortico-medullary border and thymic medulla. Phenotypically, γ/δ thymocytes from fetal and neonatal thymus expressed CD3, CD2, and CD5, but only 60-80% were CD8+ and approximately 40-50% expressed the α chain (p55) of the IL-2R. In the periphery, the immunohistological study identified for the first time ,γ/δ T cells in the splenic white pulp and the gut of 21-day fetal rats, where they occurred within the epithelium as well as in the lamina propria. After birth, γ/δ lymphocytes appeared in the skin, where they were present as dendritic epidermal T cells in increasing numbers during postnatal life. Whereas these γ/δ T cells formed the predominant T-cell population in the rat skin, γ/δ T cells in peripheral lymphoid organs, BALT, or the gut only represented a minor T-cell population. These results are discussed in comparison to γ/δ T cells of other vertebrate species. PMID:8770557

  12. Acute lethal graft-versus-host disease stimulates cellular proliferation in the adult rat liver.

    PubMed

    Klein, R M; Clancy, J; Stuart, S

    1982-11-01

    The present investigation was designed to analyse the effects of acute lethal graft-versus-host disease (GVHD) in adult (DA x LEW)F1 rats on cellular proliferation within the liver. The influence of the host thymus on GVHD-induced proliferation was also assessed. From 1-28 days after initiation of GVHD [3H]thymidine ([3H]-TdR) was injected i.v. and rats were killed one hour later. Percentage labelled cells (LI) of periportal infiltrating cells (PIC), hepatocytes (H), and sinusoidal lining cells (SC) were counted. Mean values for control rats were 0.3 +/- 0.1% (H), 0.4 +/- 0.1% (SC) and 0.2 +/- 0.1% (PIC). GVHD rats demonstrated a significant increase in LI of PIC (days 1-21), SC (days 2-17) and H (days 2-17). Most labelled cells in PIC were large lymphocytes. Peak LI values were 7.0 +/- 1.0% PIC (day 17), 6.8 +/- 0.9% SC (day 17), and 5.2 +/- 0.9% H (day 7), with all cellular compartments returning to near normal LI values by day 28. Stimulation of cellular proliferation occurred in all three liver cell compartments in neonatally thymectomized (TXM) rats. The intensity of GVHD-induced cell proliferation was significantly decreased at day 7 in all compartments and PIC was dramatically decreased at day 21 in TXM-GVHD rats as compared to non-TXM-GVHD rats. It is hypothesized that the general stimulation of hepatocyte cell proliferation in GVHD is related to the secretion of lymphokines by primarily donor and secondarily host T cells in the periportal infiltrate. PMID:7172201

  13. Hypothyroidism increases prolactin secretion and decreases the intromission threshold for induction of pseudopregnancy in adult female rats.

    PubMed

    Tohei, A; Taya, K; Watanabe, G; Voogt, J L

    In order to understand the mechanism by which thyroid hormones alter prolactin (PRL) secretion, we investigated the role of tuberoinfundibular dopamine (TIDA) neurons and pituitary and hypothalamus vasoactive intestinal peptide (VIP) in thiouracil- (0. 03% in drinking water for 16 days) induced-hypothyroid adult female rats. The intromission threshold for induction of pseudopregnancy also was examined to evaluate the PRL response to coital stimulation in hypothyroid rats. Hypothyroidism in adult female rats did not affect TIDA neuronal activity as measured by tyrosine hydroxylase activity (DOPA accumulation 30 min after administration of m-hydroxybenzylhydrazine dihydrochloride, 100 mg/kg, i.p.) in the stalk-median eminence compared with that in euthyroid rats, whereas pituitary concentration of VIP was dramatically increased. Plasma concentration of PRL was higher at 1100 h of proestrus and estrus in hypothyroid rats as compared with that of euthyroid rats. The proportion of female rats exhibiting pseudopregnancy was higher in hypothyroid animals (100%) receiving seven intromissions than in euthyroid animals (43%). Administration of L-thyroxine in hypothyroid rats decreased the proportion of pseudopregnancy (40%) to the level of euthyroid animals. These results indicate that the increased level of pituitary VIP probably affects PRL secretion in a paracrine or autocrine manner and account for the hyperprolactinemia induced in hypothyroid female rats. No role for TIDA neurons in PRL elevation can be ascribed. A decrease in the intromission threshold for induction of pseudopregnancy might be due to increased levels of PRL in hypothyroid female rats.

  14. Hematopoietic bone marrow cells participate in endothelial, but not epithelial or mesenchymal cell renewal in adult rats

    PubMed Central

    Odörfer, Kathrin I; Egerbacher, Monika; Unger, Nina J; Weber, Karin; Jamnig, Angelika; Lepperdinger, Günter; Kleiter, Miriam; Sandgren, Eric P; Erben, Reinhold G

    2011-01-01

    The extent to which bone marrow (BM) contributes to physiological cell renewal is still controversial. Using the marker human placental alkaline phosphatase (ALPP) which can readily be detected in paraffin and plastic sections by histochemistry or immunohistochemistry, and in ultrathin sections by electron microscopy after pre-embedding staining, we examined the role of endogenous BM in physiological cell renewal by analysing tissues from lethally irradiated wild-type inbred Fischer 344 (F344) rats transplanted (BMT) with unfractionated BM from ALPP-transgenic F344 rats ubiquitously expressing the marker. Histochemical, immunohistochemical and immunoelectron microscopic analysis showed that the proportion of ALPP+ capillary endothelial cells (EC) profoundly increased from 1 until 6 months after BMT in all organs except brain and adrenal medulla. In contrast, pericytes and EC in large blood vessels were ALPP–. Epithelial cells in kidney, liver, pancreas, intestine and brain were recipient-derived at all time-points. Similarly, osteoblasts, chondrocytes, striated muscle and smooth muscle cells were exclusively of recipient origin. The lack of mesenchymal BM-derived cells in peripheral tissues prompted us to examine whether BMT resulted in engraftment of mesenchymal precursors. Four weeks after BMT, all haematopoietic BM cells were of donor origin by flow cytometric analysis, whereas isolation of BM mesenchymal stem cells (MSC) failed to show engraftment of donor MSC. In conclusion, our data show that BM is an important source of physiological renewal of EC in adult rats, but raise doubt whether reconstituted irradiated rats are an apt model for BM-derived regeneration of mesenchymal cells in peripheral tissues. PMID:21091631

  15. Differential Effects of Inhaled Toluene on Locomotor Activity in Adolescent and Adult Rats

    PubMed Central

    Batis, Jeffery C.; Hannigan, John H.; Bowen, Scott E.

    2010-01-01

    Inhalant abuse is a world-wide public health concern among adolescents. Most preclinical studies have assessed inhalant effects in adult animals leaving unclear how behavioral effects differ in younger animals. We exposed adolescent (postnatal day [PN] 28) and adult (PN90) male rats to toluene using 1 of 3 exposure patterns. These patterns modeled those reported in toluene abuse in teens and varied concentration, number and length of exposures, as well as the inter-exposure interval. Animals were exposed repeatedly over 12 days to toluene concentrations of 0, 8,000 or 16,000 parts per million (ppm). Locomotor activity was quantified during toluene exposures and for 30 min following completion of the final daily toluene exposure. For each exposure pattern, there were significant toluene concentration-related increases and decreases in locomotor activity compared to the 0-ppm “air” controls at both ages. These changes depended upon when activity was measured – during or following exposure. Compared to adults, adolescents displayed greater locomotor activity on the first day and generally greater increases in activity over days than adults during toluene exposure. Adults displayed greater locomotor activity than adolescents in the “recovery” period following exposure on the first and subsequent days. Age group differences were clearest following the pattern of paced, brief (5-min) repeated binge exposures. The results suggest that locomotor behavior in rats during and following inhalation of high concentrations of toluene depends on age and the pattern of exposure. The results are consistent with dose-dependent shifts in sensitivity and sensitization or tolerance to repeated toluene in the adolescent animals compared to the adult animals. Alternate interpretations are possible and our interpretation is limited by the range of very high concentrations of toluene used. The results imply that both pharmacological and psychosocial factors contribute to the teen

  16. Infrasound increases intracellular calcium concentration and induces apoptosis in hippocampi of adult rats.

    PubMed

    Liu, Zhaohui; Gong, Li; Li, Xiaofang; Ye, Lin; Wang, Bin; Liu, Jing; Qiu, Jianyong; Jiao, Huiduo; Zhang, Wendong; Chen, Jingzao; Wang, Jiuping

    2012-01-01

    In the present study, we determined the effect of infrasonic exposure on apoptosis and intracellular free Ca²⁺ ([Ca²⁺]i) levels in the hippocampus of adult rats. Adult rats were randomly divided into the control and infrasound exposure groups. For infrasound treatment, animals received infrasonic exposure at 90 (8 Hz) or 130 dB (8 Hz) for 2 h per day. Hippocampi were dissected, and isolated hippocampal neurons were cultured. The [Ca²⁺]i levels in hippocampal neurons from adult rat brains were determined by Fluo-3/AM staining with a confocal microscope system on days 1, 7, 14, 21 and 28 following infrasonic exposure. Apoptosis was evaluated by Annexin V-FITC and propidium iodide double staining. Positive cells were sorted and analyzed by flow cytometry. Elevated [Ca²⁺]i levels were observed on days 14 and 21 after rats received daily treatment with 90 or 130 dB sound pressure level (SPL) infrasonic exposure (p<0.01 vs. control). The highest levels of [Ca²⁺]i were detected in the 130 dB SPL infrasonic exposure group. Meanwhile, apoptosis in hippocampal neurons was found to increase on day 7 following 90 dB SPL infrasound exposure, and significantly increased on day 14. Upon 130 dB infrasound treatment, apoptosis was first observed on day 14, whereas the number of apoptotic cells gradually decreased thereafter. Additionally, a marked correlation between cell apoptosis and [Ca²⁺]i levels was found on day 14 and 21 following daily treatment with 90 and 130 dB SPL, respectively. These results demonstrate that a period of infrasonic exposure induced apoptosis and upregulated [Ca²⁺]i levels in hippocampal neurons, suggesting that infrasound may cause damage to the central nervous system (CNS) through the Ca²⁺‑mediated apoptotic pathway in hippocampal neurons. PMID:21946944

  17. Perinatal iron deficiency affects locomotor behavior and water maze performance in adult male and female rats.

    PubMed

    Bourque, Stephane L; Iqbal, Umar; Reynolds, James N; Adams, Michael A; Nakatsu, Kanji

    2008-05-01

    Iron deficiency during early growth and development adversely affects multiple facets of cognition and behavior in adult rats. The purpose of this study was to assess the nature of the learning and locomotor behavioral deficits observed in male and female rats in the absence of depressed brain iron levels at the time of testing. Adult female Wistar rats were fed either an iron-enriched diet (>225 mg/kg Fe) or an iron-restricted diet (3 mg/kg Fe) for 2 wk prior to and throughout gestation, and a nonpurified diet (270 mg/kg Fe) thereafter. Open-field (OF) and Morris water maze (MWM) testing began when the offspring reached early adulthood (12 wk). At birth, perinatal iron-deficient (PID) offspring had reduced (P < 0.001) hematocrits (-33%), liver iron stores (-83%), and brain iron concentrations (-38%) compared with controls. Although there were no differences in iron status in adults, the PID males and females exhibited reduced OF exploratory behavior, albeit only PID males had an aversion to the center of the apparatus (2.5 vs. 6.9% in controls, P < 0.001). Additionally, PID males required greater path lengths to reach the hidden platform in the MWM, had reduced spatial bias for the target quadrant, and had a tendency for greater thigmotactic behavior in the probe trials (16.5 vs. 13.0% in controls; P = 0.06). PID females had slower swim speeds in all testing phases (-6.2%; P < 0.001). These results suggest that PID has detrimental programming effects in both male and female rats, although the behaviors suggest different mechanisms may be involved in each sex.

  18. Efficacy of Retigabine on Acute Limbic Seizures in Adult Rats

    PubMed Central

    Friedman, LK; Slomko, AM; Wongvravit, JP; Naseer, Z; Hu, S; Wan, WY; Ali, SS

    2015-01-01

    Background and Purpose: The efficacy of retigabine (RGB), a positive allosteric modulator of K+ channels indicated for adjunct treatment of partial seizures, was studied in two adult models of kainic acid (KA)-induced status epilepticus to determine it’s toleratbility. Methods: Retigabine was administered systemiclly at high (5 mg/kg) and low (1–2 mg/kg) doses either 30 min prior to or 2 hr after KA-induced status epilepticus. High (1 µg/µL) and low (0.25 µg/µL) concentrations of RGB were also delivered by intrahippocampal microinjection in the presence of KA. Results: Dose-dependent effects of RGB were observed with both models. Lower doses increased seizure behavior latency and reduced the number of single spikes and synchronized burst events in the electroencephalogram (EEG). Higher doses worsened seizure behavior, produced severe ataxia, and increased spiking activity. Animals treated with RGB that were resistant to seizures did not exhibit significant injury or loss in GluR1 expression; however if stage 5–6 seizures were reached, typical hippocampal injury and depletion of GluR1 subunit protein in vulernable pyramidal fields occurred. Conclusions: RGB was neuroprotective only if seizures were significantly attenuated. GluR1 was simultaneously suppressed in the resistant granule cell layer in presence of RGB which may weaken excitatory transmission. Biphasic effects observed herein suggest that the human dosage must be carefully scrutinized to produce the optimal clinical response. PMID:26819936

  19. Histomorphometric evaluation of renal glomeruli exposed to sustained delivery of estrogen using adult ovariectomized rats.

    PubMed

    Hafez, Naiel A; Benghuzzi, Hamed; Tucci, Michelle

    2003-01-01

    Hormonal replacement therapy (HRT) has shown to be efficacious in treatment and preventing of heart disease, osteoporosis and reducing mortality in postmenopausal and ovariectomized females. Several attempts to utilize the native estrogen and its analogs such as Depo-Provera, conjugated estrogen and estrogen benzoate have shown different physiological responses. In addition, the route of administration and its mode of action is lacking in the literature. The specific objective of this study was to investigate the role of sustained delivery of estrogen on the functional and structural capacity of the kidney using adult female rats as a model. A total of 24 adult female rats were subdivided into four equal groups. Groups I and II were ovariectomized (OVX) by following standard laboratory surgical procedures. Each rat in groups II and III (intact) were implanted with tricalcium phosphate lysine (TCPL) drug delivery system loaded with 40 mg of estrogen. Rats in group IV were unimplanted and untreated to be served as a control group. At the end of 45 days post treatment the animals were sacrificed by using overdose of Halothane and assured by cervical dislocation. Vital and reproductive organs were retrieved, weighed and subjected to H&E staining procedure. The results of this investigation suggest: (i) TCPL delivery system released estrogen at a sustained level for 45 days without any untoward response, (ii) the wet weights of kidneys (normalized to body weight) were increased (p < 0.05) in intact rats treated with estrogen compared to control, (iii) sustained delivery of estrogen resulted in a maintenance of kidney weights compared to the control level, however, the lack of estrogen treatment resulted in a remarkable regression in the kidney weights of OVX rats, (iv) the ratio of renal arteries-diameter (normalized to arterial wall thickness) was significantly increased in intact rats treated with estrogen compared to the control and other experimental groups, (v

  20. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity.

    PubMed

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S

    2016-04-12

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or "deviance" detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons' overall tuning widths.

  1. Neurons in the inferior colliculus of the rat show stimulus-specific adaptation for frequency, but not for intensity

    PubMed Central

    Duque, Daniel; Wang, Xin; Nieto-Diego, Javier; Krumbholz, Katrin; Malmierca, Manuel S.

    2016-01-01

    Electrophysiological and psychophysical responses to a low-intensity probe sound tend to be suppressed by a preceding high-intensity adaptor sound. Nevertheless, rare low-intensity deviant sounds presented among frequent high-intensity standard sounds in an intensity oddball paradigm can elicit an electroencephalographic mismatch negativity (MMN) response. This has been taken to suggest that the MMN is a correlate of true change or “deviance” detection. A key question is where in the ascending auditory pathway true deviance sensitivity first emerges. Here, we addressed this question by measuring low-intensity deviant responses from single units in the inferior colliculus (IC) of anesthetized rats. If the IC exhibits true deviance sensitivity to intensity, IC neurons should show enhanced responses to low-intensity deviant sounds presented among high-intensity standards. Contrary to this prediction, deviant responses were only enhanced when the standards and deviants differed in frequency. The results could be explained with a model assuming that IC neurons integrate over multiple frequency-tuned channels and that adaptation occurs within each channel independently. We used an adaptation paradigm with multiple repeated adaptors to measure the tuning widths of these adaption channels in relation to the neurons’ overall tuning widths. PMID:27066835

  2. Phosphorylation of Ser-180 of rat aquaporin-4 shows marginal affect on regulation of water permeability: molecular dynamics study.

    PubMed

    Sachdeva, Ruchi; Singh, Balvinder

    2014-04-01

    Water permeation through rat aquaporin-4 (rAQP4), predominantly found in mammalian brain is regulated by phosphorylation of Ser-180. The present study has been carried out to understand the structural mechanism of regulation of water permeability across the channel. Molecular dynamics (MD) simulations have been carried out to investigate the structural changes caused due to phosphorylation of Ser-180 in the tetrameric assembly of rAQP4 along with predicted C-terminal region (255-323). The interactions involving opposite charges are observed between cytoplasmic loops and the C-terminal region during MD simulations. This results in movement of C-terminal region of rAQP4 towards the cytoplasmic mouth of water channel. Despite this movement, there was a gap between C-terminal region and cytoplasmic mouth of the channel through which water molecules were able to gain entry into the channel. The interactions between C-terminus and loop D of neighboring monomers in a tetrameric assembly appear to prevent the complete closure of cytoplasmic mouth of the water channel. Further, the rates of water permeation through phosphorylated and unphosphorylated rAQP4 have also been compared. The simulation studies showed a continuous movement of water in a single file across pore of unphosphorylated as well as phosphorylated rAQP4. PMID:23651078

  3. Younger Adults Show Long-Term Effects of Cognitive Training on Broad Cognitive Abilities over 2 Years

    ERIC Educational Resources Information Center

    Schmiedek, Florian; Lövdén, Martin; Lindenberger, Ulman

    2014-01-01

    In the COGITO study (Schmiedek, Lövdén, & Lindenberger, 2010), 101 younger adults practiced 12 tests of perceptual speed, working memory, and episodic memory for over 100 daily 1-hr sessions. The intervention resulted in positive transfer to broad cognitive abilities, including reasoning and episodic memory. Here, we examine whether these…

  4. Preschoolers with Down Syndrome Do Not yet Show the Learning and Memory Impairments Seen in Adults with Down Syndrome

    ERIC Educational Resources Information Center

    Roberts, Lynette V.; Richmond, Jenny L.

    2015-01-01

    Individuals with Down syndrome (DS) exhibit a behavioral phenotype of specific strengths and weaknesses, in addition to a generalized cognitive delay. In particular, adults with DS exhibit specific deficits in learning and memory processes that depend on the hippocampus, and there is some suggestion of impairments on executive function tasks that…

  5. Induction of Adult T-Cell Leukemia-Like Lymphoproliferative Disease and Its Inhibition by Adoptive Immunotherapy in T-Cell-Deficient Nude Rats Inoculated with Syngeneic Human T-Cell Leukemia Virus Type 1-Immortalized Cells

    PubMed Central

    Ohashi, Takashi; Hanabuchi, Shino; Kato, Hirotomo; Koya, Yoshihiro; Takemura, Fumiyo; Hirokawa, Katsuiku; Yoshiki, Takashi; Tanaka, Yuetsu; Fujii, Masahiro; Kannagi, Mari

    1999-01-01

    Human T-cell leukemia virus type 1 (HTLV-1) has been shown to be the etiologic agent of adult T-cell leukemia (ATL), but the in vivo mechanism by which the virus causes the malignant transformation is largely unknown. In order to investigate the mechanisms of HTLV-1 leukemogenesis, we developed a rat model system in which ATL-like disease was reproducibly observed, following inoculation of various rat HTLV-1-immortalized cell lines. When previously established cell lines, F344-S1 and TARS-1, but not TART-1 or W7TM-1, were inoculated, systemic multiple tumor development was observed in adult nude (nu/nu) rats. FPM1 cells, newly established from a heterozygous (nu/+) rat syngeneic to nu/nu rats, caused transient tumors only at the injection site in adult nu/nu rats, but could progressively grow in newborn nu/nu rats and metastasize in lymph nodes. The derivative cell line (FPM1-V1AX) serially passed through newborn nu/nu rats acquired the potency to grow in adult nu/nu rats. These results indicated that only some with additional changes but not all of the in vitro HTLV-1-immortalized cell lines possessed in vivo tumorigenicity. Using the syngeneic system, we further showed the inhibition of tumor development by transferring splenic T cells from immunized rats, suggesting the involvement of T cells in the regression of tumors. This novel and reproducible nude rat model of human ATL would be useful for investigation of leukemogenesis and antitumor immune responses in HTLV-1 infection. PMID:10364355

  6. Post-weaning environmental enrichment improves BDNF response of adult male rats.

    PubMed

    Mosaferi, Belal; Babri, Shirin; Mohaddes, Gisou; Khamnei, Saeed; Mesgari, Mehran

    2015-11-01

    The environment could have long lasting effects on the individual phenotype through developmental plasticity. Early environmental enrichment exerts profound biological effects, most of which are quite beneficial ones. To explore the enduring effects of rearing condition quality on BDNF(1) responses, we reared male Wistar rats from weaning to young-adulthood in three different environmental conditions: 1. Enriched 2. Standard, and 3. Isolated. Then, at the age of 16 weeks, 10 rats from each group were randomly chosen and allocated to six common mix cages. They were kept together for 14 weeks. At the end of the experiment, each rat received ten inescapable foot-shocks. Twelve hours later, the BDNF contents of the amygdala and CA1 sub-region of the dorsal hippocampus were measured. The serum BDNF levels, hematocrit values as well as brain and testis weights were also measured. Results showed that the environmental enrichment led to stronger dorsal hippocampal BDNF response and higher serum BDNF levels, while rats from standard laboratory condition showed higher amygdala BDNF response. Also, enriched animals showed higher brain weight compared to isolation reared rats as well as higher testis weight and hematocrit value compared to animals reared in standard laboratory condition. Rats showed less body weights in isolated condition. In conclusion, the BDNF profile of enriched animals might represent the neurobiological correlate of resilience phenotype under a stressful situation.

  7. Expression and immunolocalization of Gpnmb, a glioma-associated glycoprotein, in normal and inflamed central nervous systems of adult rats

    PubMed Central

    Huang, Jian-Jun; Ma, Wen-Jie; Yokoyama, Shigeru

    2012-01-01

    Glycoprotein nonmetastatic melanoma B (Gpnmb) is a type I transmembrane protein implicated in cell differentiation, inflammation, tissue regeneration, and tumor progression. Gpnmb, which is highly expressed in glioblastoma cells, is a potential therapeutic target. However, little is known about its expression, cellular localization, and roles in non-tumorous neural tissues. In this study, we examined Gpnmb expression in the central nervous system of adult rats under both normal and inflammatory conditions. Reverse transcription-polymerase chain reaction analysis revealed that Gpnmb mRNA was expressed in the cerebrum, cerebellum, brain stem, and spinal cord of normal adult rats. Immunoperoxidase staining revealed that Gpnmb-immunoreactive cells were widely distributed in the parenchyma of all brain regions examined, with the cells being most prevalent in the hippocampal dentate gyrus, cerebellar cortex, spinal dorsal horn, choroid plexus, ependyma, periventricular regions, and in layers II and III of the cerebral cortex. Double immunofluorescence staining showed that these cells were co-stained most frequently with the microglia/macrophage marker OX42, and occasionally with the radial glia marker RC2 or the neuronal marker NeuN. Furthermore, an intraperitoneal injection of bacterial endotoxin lipopolysaccharide increased the number of Gpnmb and OX42 double-positive cells in the area postrema, which is one of the circumventricular organs, indicating infiltration of hematogenous macrophages. These results suggest that Gpnmb, which is expressed in microglia and macrophages in non-tumorous neural tissues, plays an important role in the regulation of immune/inflammatory responses. PMID:22574278

  8. Embedding a Panoramic Representation of Infrared Light in the Adult Rat Somatosensory Cortex through a Sensory Neuroprosthesis.

    PubMed

    Hartmann, Konstantin; Thomson, Eric E; Zea, Ivan; Yun, Richy; Mullen, Peter; Canarick, Jay; Huh, Albert; Nicolelis, Miguel A L

    2016-02-24

    Can the adult brain assimilate a novel, topographically organized, sensory modality into its perceptual repertoire? To test this, we implemented a microstimulation-based neuroprosthesis that rats used to discriminate among infrared (IR) light sources. This system continuously relayed information from four IR sensors that were distributed to provide a panoramic view of IR sources, into primary somatosensory cortex (S1). Rats learned to discriminate the location of IR sources in <4 d. Animals in which IR information was delivered in spatial register with whisker topography learned the task more quickly. Further, in animals that had learned to use the prosthesis, altering the topographic mapping from IR sensor to stimulating electrode had immediate deleterious effects on discrimination performance. Multielectrode recordings revealed that S1 neurons had multimodal (tactile/IR) receptive fields, with clear preferences for those stimuli most likely to be delivered during the task. Neuronal populations predicted, with high accuracy, which stimulation pattern was present in small (75 ms) time windows. Surprisingly, when identical microstimulation patterns were delivered during an unrelated task, cortical activity in S1 was strongly suppressed. Overall, these results show that the adult mammalian neocortex can readily absorb completely new information sources into its representational repertoire, and use this information in the production of adaptive behaviors. PMID:26911689

  9. Environmental enrichment alters glial antigen expression and neuroimmune function in the adult rat hippocampus.

    PubMed

    Williamson, Lauren L; Chao, Agnes; Bilbo, Staci D

    2012-03-01

    Neurogenesis is a well-characterized phenomenon within the dentate gyrus (DG) of the adult hippocampus. Environmental enrichment (EE) in rodents increases neurogenesis, enhances cognition, and promotes recovery from injury. However, little is known about the effects of EE on glia (astrocytes and microglia). Given their importance in neural repair, we predicted that EE would modulate glial phenotype and/or function within the hippocampus. Adult male rats were housed either 12 h/day in an enriched environment or in a standard home cage. Rats were injected with BrdU at 1 week, and after 7 weeks, half of the rats from each housing group were injected with lipopolysaccharide (LPS), and cytokine and chemokine expression was assessed within the periphery, hippocampus and cortex. Enriched rats had a markedly blunted pro-inflammatory response to LPS within the hippocampus. Specifically, expression of the chemokines Ccl2, Ccl3 and Cxcl2, several members of the tumor necrosis factor (TNF) family, and the pro-inflammatory cytokine IL-1β were all significantly decreased following LPS administration in EE rats compared to controls. EE did not impact the inflammatory response to LPS in the cortex. Moreover, EE significantly increased both astrocyte (GFAP+) and microglia (Iba1+) antigen expression within the DG, but not in the CA1, CA3, or cortex. Measures of neurogenesis were not impacted by EE (BrdU and DCX staining), although hippocampal BDNF mRNA was significantly increased by EE. This study demonstrates the importance of environmental factors on the function of the immune system specifically within the brain, which can have profound effects on neural function.

  10. A Microdialysis Study of the Medial Prefrontal Cortex of Adolescent and Adult Rats

    PubMed Central

    Staiti, Amanda M.; Morgane, Peter J.; Galler, Janina R.; Grivetti, Janice Y.; Bass, Donna C.; Mokler, David J.

    2011-01-01

    The medial prefrontal cortex (mPFC) of the rat has become a key focus of studies designed to elucidate the basis of behavior involving attention and decision making, i.e. executive functions. The adolescent mPFC is of particular interest given the role of the mPFC in impulsivity and attention, and disorders such as attentional deficit disorder. In the present study we have examined the basal extracellular concentrations of the neurotransmitters 5-hydroxytryptamine (5-HT), dopamine (DA) and norepinephrine (NE) in the ventral portion of the mPFC (vmPFC) in both adolescent (post-natal day 45–50) and adult, and male and female rats using in vivo microdialysis. We have also examined both the left and right vmPFCs given reports of laterality in function between the hemispheres. Basal extracellular concentrations of 5-HT differed significantly between male and female rats. Extracellular DA also differed significantly between male and female rats and between the left and the right vmPFC in adult males. No differences were seen in basal extracellular NE. There was a significant age difference between groups in the laterality of extracellular NE levels between right and left vmPFC. Infusion of 100 µM methamphetamine through the dialysis probe increased the extracellular concentration of all the monoamines although there were no differences between groups in methamphetamine stimulated release. The findings from this study demonstrate that there are differences in monoaminergic input to the mPFC of the rat based on age, gender and hemisphere. This work sets the neurochemical baseline for further investigations of the prefrontal cortex during development. PMID:21527264

  11. Histological correlates of N40 auditory evoked potentials in adult rats after neonatal ventral hippocampal lesion: animal model of schizophrenia.

    PubMed

    Romero-Pimentel, A L; Vázquez-Roque, R A; Camacho-Abrego, I; Hoffman, K L; Linares, P; Flores, G; Manjarrez, E

    2014-11-01

    The neonatal ventral hippocampal lesion (NVHL) is an established neurodevelopmental rat model of schizophrenia. Rats with NVHL exhibit several behavioral, molecular and physiological abnormalities that are similar to those found in schizophrenics. Schizophrenia is a severe psychiatric illness characterized by profound disturbances of mental functions including neurophysiological deficits in brain information processing. These deficits can be assessed by auditory evoked potentials (AEPs), where schizophrenics exhibit abnormalities in amplitude, duration and latency of such AEPs. The aim of the present study was to compare the density of cells in the temporal cerebral cortex and the N40-AEP of adult NVHL rats versus adult sham rats. We found that rats with NVHL exhibit significant lower amplitude of the N40-AEP and a significant lower number of cells in bilateral regions of the temporal cerebral cortex compared to sham rats. Because the AEP recordings were obtained from anesthetized rats, we suggest that NVHL leads to inappropriate innervation in thalamic-cortical pathways in the adult rat, leading to altered function of cortical networks involved in processing of primary auditory information.

  12. Protective effect of curcumin against experimentally induced aflatoxicosis on the renal cortex of adult male albino rats: a histological and immunohisochemical study

    PubMed Central

    El-Mahalaway, Abeer M

    2015-01-01

    Background: Aflatoxin contamination of foods is a worldwide problem. Chronic aflatoxin exposure is associated with kidney damage. Curcumin is a herbal agent, used in medicine with a wide range of beneficial therapeutic effects. Objective: to evaluate the effect of curcumin against experimentally induced aflatoxicosis on the renal cortex of adult male albino rats. Materials and methods: Forty adult male rats were included and they were divided equally into 4 groups (10 rats each): Group I (control group), group II (Curcumin group): The rats received curcumin (200 mg/kg b.w.) orally by gastric tube for 5 days/week, group III (Aflatoxin B1 group): The rats received aflatoxin B1 (250 μg/kg b.w./day) orally by gastric tube 5 days/week for 4 weeks, group IV (Aflatoxin B1 and Curcumin group): The rats received aflatoxin and curcumin orally by gastric tube 5 days/week for 4 weeks. Kidney specimens were prepared and sections were stained with hematoxylin and eosin, Masson’s trichrome, Periodic acid Schiff, immunohistochemical detection of desmin and Bcl2. Results: The tubules of group III showed degenerative and necrotic changes with disruption of basal lamina. There was a significant decrease Bcl2 expression in the tubules, but the glomeruli showed an enlargement with dilation of their capillaries lumina in some areas, while the other areas showed glomerular atrophy with obliteration of their capillaries lumina. There was a significant increase in desmin expression in the glomerular cells. The interstitium showed hemorrhage and cellular infiltration. Group IV showed improvement of the histological and immunohistochemical changes described before. Conclusion: Aflatoxin B1 has deleterious effects of on the histological structure of the rat’s renal cortex and curcumin minimized these effects as it has antioxidant, anti-inflammatory and antiapoptotic activities. We advise eating nutritious diets that contain sufficient amounts of curcumin and regulation must implement to

  13. Male-specific suppression of hepatic microsomal UDP-glucuronosyl transferase activities toward sex hormones in the adult male rat administered bisphenol A.

    PubMed Central

    Shibata, Noriaki; Matsumoto, Junya; Nakada, Ken; Yuasa, Akira; Yokota, Hiroshi

    2002-01-01

    Various adverse effects of endocrine disruptors on the reproductive organs of male animals have been reported. We found that UDP-glucuronosyltransferase (UGT) activities towards bisphenol A, testosterone and oestradiol were significantly decreased in liver microsomes prepared from adult male Wistar rats administered with the endocrine disruptor bisphenol A (1 mg/2 days for 2 or 4 weeks). However, suppression of the transferase activities was not observed in female rats, even after bisphenol A treatment for 4 weeks. Diethylstilbestrol, which is well known as an endocrine disruptor, had the same effects, but p -cumylphenol had no effect on UGT activities towards sex hormones. Co-administration of an anti-oestrogen, tamoxifen, inhibited the suppression of the transferase activities by bisphenol A. Western blotting analysis showed that the amount of UGT2B1, an isoform of UGT which glucuronidates bisphenol A, was decreased in the rat liver microsomes by the treatment. Northern blotting analysis also indicated that UGT2B1 mRNA in the liver was decreased by bisphenol A treatment. The suppression of UGT activities, UGT2B1 protein and UGT2B1 mRNA expression did not occur in female rats. The results indicate that bisphenol A treatment reduces the mRNA expression of UGT2B1 and other UGT isoforms that mediate the glucuronidation of sex hormones in adult male rats, and this suggests that the endocrine balance may be disrupted by suppression of glucuronidation. PMID:12230427

  14. Changes in spontaneous behaviour and altered response to nicotine in the adult rat, after neonatal exposure to the brominated flame retardant, decabrominated diphenyl ether (PBDE 209).

    PubMed

    Viberg, Henrik; Fredriksson, Anders; Eriksson, Per

    2007-01-01

    Polybrominated diphenyl ethers (PBDEs), which are used as flame retardants, have recently been shown to increase in the environment and in human milk, which is also true for the decabrominated congener, 2,2',3,3',4,4',5,5',6,6'-decaBDE (PBDE 209). We have recently reported that neonatal exposure to PBDE 209 can induce persistent aberrations in spontaneous behaviour, in mice, effects that get worse with age. Other PBDE congeners affect learning and memory functions and the cholinergic system in adult mice and rats. The present study indicates that spontaneous behaviour, along with the cholinergic system during its developing stage, can be targets for PBDE 209 in the rat. Neonatal oral exposure of male Sprague-Dawley rats, on postnatal day 3, to 6.7, and 20.1 mg PBDE 209/kg body weight, was shown to disrupt normal spontaneous behaviour at 2 months of age. Also, rats exposed to the high dose of PBDE 209 showed a different response to adult nicotine treatment, compared to control rats. These findings show similarities to observations made from neonatal exposure of rats or mice to 2,2',4,4',5-pentaBDE (PBDE 99), 2,2',4,4',5,5'-hexaBDE (PBDE 153) and certain PCBs, compounds shown to affect both spontaneous behaviour and the cholinergic system. It is also clear from the present study and from recent studies from our research group that both lower and higher brominated diphenyl ethers can cause similar developmental neurotoxic effects in both mice and rats. PMID:17030062

  15. Impacts of prenatal nanomaterial exposure on male adult Sprague-Dawley rat behavior and cognition.

    PubMed

    Engler-Chiurazzi, Elizabeth B; Stapleton, Phoebe A; Stalnaker, Jessica J; Ren, Xuefang; Hu, Heng; Nurkiewicz, Timothy R; McBride, Carroll R; Yi, Jinghai; Engels, Kevin; Simpkins, James W

    2016-01-01

    It is generally accepted that gestational xenobiotic exposures result in systemic consequences in the adult F1 generation. However, data on detailed behavioral and cognitive consequences remain limited. Using our whole-body nanoparticle inhalation facility, pregnant Sprague-Dawley rats (gestational day [GD] 7) were exposed 4 d/wk to either filtered air (control) or nano-titanium dioxide aerosols (nano-TiO2; count median aerodynamic diameter of 170.9 ± 6.4 nm, 10.4 ± 0.4 mg/m(3), 5 h/d) for 7.8 ± 0.5 d of the remaining gestational period. All rats received their final exposure on GD 20 prior to delivery. The calculated daily maternal deposition was 13.9 ± 0.5 µg. Subsequently, at 5 mo of age, behavior and cognitive functions of these pups were evaluated employing a standard battery of locomotion, learning, and anxiety tests. These assessments revealed significant working impairments, especially under maximal mnemonic challenge, and possible deficits in initial motivation in male F1 adults. Evidence indicates that maternal engineered nanomaterial exposure during gestation produces psychological deficits that persist into adulthood in male rats.

  16. Environmental enrichment for adult rats: effects on trait and state anxiety.

    PubMed

    Goes, Tiago Costa; Antunes, Fabrício Dias; Teixeira-Silva, Flavia

    2015-01-01

    Experimental evidence indicates that enriched environment (EE) induces neurobiological and behavioural alterations. EE in early life improves learning and memory and reduces trait and state anxiety. However, the effect of EE established in adulthood has rarely been investigated. Thus, the aim of this study was to evaluate the possibility of modifying the levels of trait and/or state anxiety of adult rats exposed to EE. Seventy adult Wistar male rats were first tested in the free-exploratory paradigm (FEP) and were categorized according to their levels of trait anxiety (high, medium and low). Subsequently, half of the animals from each category returned to their home cages (standard condition: SC) and the other half was transferred to an enriched environment (enriched condition: EC). After three weeks, all animals were again tested in FEP. Seven to 10 days later, fifty of the seventy animals were tested on the elevated plus-maze test (EPM). In FEP, EE reduced locomotor activity in the second exposition independently of the anxiety category and, it decreased the levels of trait anxiety of highly anxious rats. No effect of EE was observed on EPM. In conclusion, EE established in adulthood was able to reduce high trait anxiety, a major risk factor for anxiety disorders.

  17. Maternal separation is associated with DNA methylation and behavioural changes in adult rats.

    PubMed

    Anier, Kaili; Malinovskaja, Kristina; Pruus, Katrin; Aonurm-Helm, Anu; Zharkovsky, Alexander; Kalda, Anti

    2014-03-01

    Early life stress is known to promote long-term neurobiological changes, which may underlie the increased risk of psychopathology. Maternal separation (MS) is used as an early life stressor that causes profound neurochemical and behavioural changes in the pups that persist into adulthood. However, the exact mechanism of how MS alters these behavioural changes is not yet understood. Epigenetic modifications, such as DNA methylation, are critical regulators of persistent gene expression changes and may be related to behavioural disorders. The aim of the present study was to investigate whether early life stress on rats could alter cocaine-induced behavioural sensitisation in adulthood via aberrant DNA methylation. We have three main findings: (1) MS increased DNA methyltransferases (DNMTs) expression in the nucleus accumbens (NAc) of infant and adult rats; (2) MS induced DNA hypomethylation on a global level in the NAc, and hypermethylation of the promoter regions of the protein phosphatase 1 catalytic subunit (PP1C) and adenosine A2Areceptor (A2AR) genes, which was associated with their transcriptional downregulation in the NAc; (3) MS-induced molecular changes paralleled an increased response to cocaine-induced locomotor activity and exploratory behaviour in adult rats. Thus, our results suggest that stressful experiences in early life may create a background, via aberrant DNA methylation, which promotes the development of cocaine-induced behavioural sensitisation in adulthood. PMID:23972903

  18. Impacts of prenatal nanomaterial exposure on male adult Sprague-Dawley rat behavior and cognition.

    PubMed

    Engler-Chiurazzi, Elizabeth B; Stapleton, Phoebe A; Stalnaker, Jessica J; Ren, Xuefang; Hu, Heng; Nurkiewicz, Timothy R; McBride, Carroll R; Yi, Jinghai; Engels, Kevin; Simpkins, James W

    2016-01-01

    It is generally accepted that gestational xenobiotic exposures result in systemic consequences in the adult F1 generation. However, data on detailed behavioral and cognitive consequences remain limited. Using our whole-body nanoparticle inhalation facility, pregnant Sprague-Dawley rats (gestational day [GD] 7) were exposed 4 d/wk to either filtered air (control) or nano-titanium dioxide aerosols (nano-TiO2; count median aerodynamic diameter of 170.9 ± 6.4 nm, 10.4 ± 0.4 mg/m(3), 5 h/d) for 7.8 ± 0.5 d of the remaining gestational period. All rats received their final exposure on GD 20 prior to delivery. The calculated daily maternal deposition was 13.9 ± 0.5 µg. Subsequently, at 5 mo of age, behavior and cognitive functions of these pups were evaluated employing a standard battery of locomotion, learning, and anxiety tests. These assessments revealed significant working impairments, especially under maximal mnemonic challenge, and possible deficits in initial motivation in male F1 adults. Evidence indicates that maternal engineered nanomaterial exposure during gestation produces psychological deficits that persist into adulthood in male rats. PMID:27092594

  19. Protective effect of pumpkin seed extract on sperm characteristics, biochemical parameters and epididymal histology in adult male rats treated with cyclophosphamide.

    PubMed

    Aghaei, S; Nikzad, H; Taghizadeh, M; Tameh, A A; Taherian, A; Moravveji, A

    2014-10-01

    Cancer treatment with cyclophosphamide (CP) may result in reproductive toxicity as one of its side effects. The pumpkin seed is a rich natural source of antioxidant. We have assessed the possible protective efficacy of pumpkin seed extract on sperm characteristics, biochemical parameters and epididymal histology of CP-treated rats. Male adult Wistar rats were categorised into four groups. Group 1 served as control and received intraperitoneal (IP) injection of isotonic saline solution. Group 2 rats were treated with CP by IP injection in a single dose of 100 mg/kg body weight, only once. Group 3 and 4 received CP plus 300 and 600 mg/kg pumpkin seed extract respectively. Six weeks after treatment, sperm characteristics, biochemical parameters and histopathological changes were examined. Results showed that, sperm characteristics in CP-treated rats were significantly decreased. Biochemical analysis results showed that the co-administration of 300 mg pumpkin seed extract could increase the total antioxidant capacity (TAC) level significantly. In CP-treated rats, histopathological changes such as vacuolisation, disorganisation and separation of epididymal epithelium were observed as well. Interestingly, pumpkin seed extract could improve the above-mentioned parameters remarkably in CP-treated rats. Our findings indicated that pumpkin seed extract might be used as protective agent against CP-induced reproductive toxicity.

  20. Environmental enrichment protects against the acquisition of cocaine self-administration in adult male rats, but does not eliminate avoidance of a drug-associated saccharin cue.

    PubMed

    Puhl, Matthew D; Blum, Joshua S; Acosta-Torres, Stefany; Grigson, Patricia S

    2012-02-01

    One of the most menacing consequences of drug addiction is the devaluation of natural rewards (e.g. food, sex, work, money, caring for one's offspring). However, evidence also suggests that natural rewards, such as an enriched environment, can devalue drugs of abuse. Thus, this study used a rodent model to test whether exposure to an enriched environment could protect adult rats from acquiring cocaine self-administration and from the resultant drug-induced devaluation of a natural saccharin reward cue. Adult male Sprague-Dawley rats were implanted with intravenous jugular catheters. Rats were then separated into two housing conditions: an enriched condition, including social companions(four/cage) and novel objects (e.g. balls, polyethylene tubes, paper, etc.), and a nonenriched condition where the rats were singly housed with no novel objects. During testing, the rats were given 5-min access to 0.15% saccharin, followed by 1 h to self-administer saline or cocaine (0.167 mg/infusion) on fixed ratio and progressive ratio schedules of reinforcement. The results showed that rats that were singly housed in the nonenriched environment fell into two groups: low drug-takers (n=34) and high drug-takers (n=12). In comparison, only one out of the 22 rats housed in the enriched environment was a high drug-taker. Thus, all rats in the enriched environment, except one, behaved like low drug-takers under the nonenriched condition. As such, these rats self-administered almost no drug on either the fixed ratio or the progressive ratio schedule of reinforcement and were extremely slow to self-administer their first cocaine infusion. Interestingly, despite their very low levels of drug self-administration, low-drug-taking rats housed in the enriched environment continued to avoid intake of the drug-associated saccharin cue. Taken together, these data suggest that the enriched environment itself served as a salient natural reward that reduced cocaine seeking and cocaine taking, but

  1. Integrated phrenic responses to carotid afferent stimulation in adult rats following perinatal hyperoxia.

    PubMed Central

    Ling, L; Olson, E B; Vidruk, E H; Mitchell, G S

    1997-01-01

    1. Hypoxic ventilatory responses are greatly attenuated in adult rats exposed to moderate hyperoxia (60% O2) during the first month of life (perinatal treated rats). The present study was designed to test the hypothesis that perinatal hyperoxia impairs central integration of carotid chemoreceptor afferent inputs, thereby diminishing the hypoxic ventilatory response. 2. Time-dependent phrenic nerve responses to electrical stimulation of the carotid sinus nerve (CSN) and steady-state relationships between CSN stimulation frequency and phrenic nerve output were compared in control and perinatal treated rats. The rats were urethane anaesthetized, vagotomized, paralysed and artificially ventilated. End-tidal CO2 was monitored and maintained at isocapnic levels; arterial blood gases were determined. 3. Two stimulation protocols were used: (1) three 2 min episodes of CSN stimulation (20 Hz, 0.2 ms duration, 3 x threshold), separated by 5 min intervals; and (2) nine 45 s episodes of CSN stimulation with stimulus frequencies ranging from 0.5 to 20 Hz (0.2 ms duration, 3 x threshold), separated by 4 min intervals. 4. The mean threshold currents to elicit phrenic responses were similar between groups. Burst frequency (f, burst min-1), peak amplitude of integrated phrenic activity (integral of Phr), and minute phrenic activity (integral of Phr x f) during and after CSN stimulation were not distinguishable between groups in either protocol at any time or at any stimulus intensity (P > 0.05). 5. Perinatal hyperoxia does not alter temporal or steady-state phrenic responses to CSN stimulation, suggesting that the central integration of carotid chemoreceptor afferent inputs is not impaired in perinatal treated rats. It is speculated that carotid chemoreceptors per se are impaired in perinatal treated rats. PMID:9161991

  2. Localization of cytochrome P450 and related enzymes in adult rat testis and downregulation by estradiol and bisphenol A.

    PubMed

    Gilibili, Ravindranath Reddy; Vogl, A Wayne; Chang, Thomas K H; Bandiera, Stelvio M

    2014-07-01

    There is a growing body of evidence that exposure to endocrine disrupting chemicals and to estrogenic compounds in particular can affect the testis and male fertility. In the present study, the constitutive expression of steroidogenic and non-steroidogenic cytochrome P450 (CYP) and related enzymes in adult rat testis, and their regulation by estradiol and bisphenol A, were investigated. CYP1B1, CYP2A1, NADPH-cytochrome P450 oxidoreductase (POR) and microsomal epoxide hydrolase (mEH) proteins, together with CYP17A1 and 3β-hydroxysteroid dehydrogenase (HSD3B), were detected by immunoblot analysis in testicular microsomes prepared from untreated adult Sprague Dawley rats. In contrast, CYP1A, CYP2B, CYP2E, CYP2D, CYP2C, CYP3A, and CYP4A enzymes were not detected. Immunofluorescence staining of cryosections of perfusion-fixed testes showed that CYP1B1, CYP2A1, CYP17A1, and HSD3B were expressed exclusively or mainly in interstitial cells, whereas mEH and POR protein staining was detected both in interstitial cells and in seminiferous tubules. Testicular CYP1B1 and CYP2A1 protein levels were decreased following treatment of adult rats with estradiol benzoate at 0.004, 0.04, 0.4, or 4 μmol/kg/day or bisphenol A at 400 or 800 μmol/kg/day, for 14 days, whereas expression of HSD3B was unaffected. Testicular CYP17A1, POR, and mEH protein expression was also downregulated at the three highest dosages of estradiol benzoate and at both dosages of bisphenol A. The present study is the first to establish the cellular localization of CYP1B1, mEH, and POR in rat testis and to demonstrate the suppressive effect of bisphenol A on testicular CYP1B1, CYP2A1, mEH, and POR protein levels.

  3. Chronic MDMA induces neurochemical changes in the hippocampus of adolescent and young adult rats: Down-regulation of apoptotic markers.

    PubMed

    García-Cabrerizo, Rubén; García-Fuster, M Julia

    2015-07-01

    While hippocampus is a brain region particularly susceptible to the effects of MDMA, the cellular and molecular changes induced by MDMA are still to be fully elucidated, being the dosage regimen, the species and the developmental stage under study great variables. This study compared the effects of one and four days of MDMA administration following a binge paradigm (3×5 mg/kg, i.p., every 2 h) on inducing hippocampal neurochemical changes in adolescent (PND 37) and young adult (PND 58) rats. The results showed that chronic MDMA caused hippocampal protein deficits in adolescent and young adult rats at different levels: (1) impaired serotonergic (5-HT2A and 5-HT2C post-synaptic receptors) and GABAergic (GAD2 enzyme) signaling, and (2) decreased structural cytoskeletal neurofilament proteins (NF-H, NF-M and NF-L). Interestingly, these effects were not accompanied by an increase in apoptotic markers. In fact, chronic MDMA inhibited proteins of the apoptotic pathway (i.e., pro-apoptotic FADD, Bax and cytochrome c) leading to an inhibition of cell death markers (i.e., p-JNK1/2, cleavage of PARP-1) and suggesting regulatory mechanisms in response to the neurochemical changes caused by the drug. The data, together with the observed lack of GFAP activation, support the view that chronic MDMA effects, regardless of the rat developmental age, extends beyond neurotransmitter systems to impair other hippocampal structural cell markers. Interestingly, inhibitory changes in proteins from the apoptotic pathway might be taking place to overcome the protein deficits caused by MDMA.

  4. Chronic MDMA induces neurochemical changes in the hippocampus of adolescent and young adult rats: Down-regulation of apoptotic markers.

    PubMed

    García-Cabrerizo, Rubén; García-Fuster, M Julia

    2015-07-01

    While hippocampus is a brain region particularly susceptible to the effects of MDMA, the cellular and molecular changes induced by MDMA are still to be fully elucidated, being the dosage regimen, the species and the developmental stage under study great variables. This study compared the effects of one and four days of MDMA administration following a binge paradigm (3×5 mg/kg, i.p., every 2 h) on inducing hippocampal neurochemical changes in adolescent (PND 37) and young adult (PND 58) rats. The results showed that chronic MDMA caused hippocampal protein deficits in adolescent and young adult rats at different levels: (1) impaired serotonergic (5-HT2A and 5-HT2C post-synaptic receptors) and GABAergic (GAD2 enzyme) signaling, and (2) decreased structural cytoskeletal neurofilament proteins (NF-H, NF-M and NF-L). Interestingly, these effects were not accompanied by an increase in apoptotic markers. In fact, chronic MDMA inhibited proteins of the apoptotic pathway (i.e., pro-apoptotic FADD, Bax and cytochrome c) leading to an inhibition of cell death markers (i.e., p-JNK1/2, cleavage of PARP-1) and suggesting regulatory mechanisms in response to the neurochemical changes caused by the drug. The data, together with the observed lack of GFAP activation, support the view that chronic MDMA effects, regardless of the rat developmental age, extends beyond neurotransmitter systems to impair other hippocampal structural cell markers. Interestingly, inhibitory changes in proteins from the apoptotic pathway might be taking place to overcome the protein deficits caused by MDMA. PMID:26068050

  5. The effects of different levels of peppermint alcoholic extract on body-weight gain and blood biochemical parameters of adult male Wistar rats

    PubMed Central

    Mesbahzadeh, Behzad; Akbari, Mohsen; kor, Nasroallah Moradi; Zadeh, Jalal Bayati

    2015-01-01

    Introduction Peppermint is an efficient medicinal plant for the treatment of diseases, and it also can be used to produce raw materials in the pharmaceutical industry. The purpose of the current study was to evaluate the effects of various levels of peppermint alcoholic extract on body-weight gain and blood biochemical parameters in adult male Wistar rats. Methods This experiment was conducted using a completely randomized design (CRD). Fifty adult, healthy, male Wistar rats (ages of 2.5–3 months; weights of 190–210 g) were allocated randomly into five groups. T1 was the control group in which the rats received 0.3 ml of distilled water). Groups T2, T3, T4, and T5 received 75, 150, 300, and 600 mg/kg of peppermint extract, respectively. The rats received daily pretreatment by oral gavages for 21 days. We recorded body weights at the beginning and at the end of the study to determine the changes in the body weights. Blood samples were collected for the measurement of glucose, cholesterol, triglycerides, HDL, LDL, albumin, globulin, and total protein. Statistical analysis of the data was done by SAS software. The data statistically analyzed using one-way analysis of variance (ANOVA), which was conducted through Dennett’s multiple comparison post-test. Results The results indicated that the rats treated with peppermint gained more weight (p < 0.05) and also decreased the serum concentrations of triglycerides, total cholesterol, LDL, and glucose in T3, T4 and T5 than the other groups (p < 0.05). Conclusion Peppermint extract had a positive effect on body-weight gain and some blood parameters in adult male Wistar rats. The findings showed that peppermint is a crucial substance at high temperature, and future research should be focused on determining the details of the mechanisms involved in producing the observed effects of peppermint extract. PMID:26516445

  6. Astrocytes in the Rat Medial Amygdala Are Responsive to Adult Androgens

    PubMed Central

    Johnson, Ryan T.; Schneider, Amanda; DonCarlos, Lydia L.; Breedlove, S. Marc; Jordan, Cynthia L.

    2014-01-01

    The posterodorsal medial amygdala (MePD) exhibits numerous sex differences including differences in volume and in the number and morphology of neurons and astroctyes. In adulthood, gonadal hormones, including both androgens and estrogens, have been shown to play a role in maintaining the masculine character of many of these sex differences, but whether adult gonadal hormones maintain the increased number and complexity of astrocytes in the male MePD was unknown. To answer this question we examined astrocytes in the MePD of male and female Long Evans rats that were gonadectomized as adults and treated for 30 days with either testosterone or a control treatment. At the end of treatment brains were collected and immunostained for glial fibrillary acidic protein. Stereological analysis revealed that adult androgen levels influenced the number and complexity of astrocytes in the MePD of both sexes, but the specific effects of androgens were different in males and females. However, sex differences in the number and complexity of adult astrocytes persisted even in the absence of gonadal hormones in adulthood, suggesting that androgens also act earlier in life to determine these adult sex differences. Using immunofluorescence and confocal microscopy, we found robust androgen receptor immunostaining in a subpopulation of MePD astrocytes, suggesting that testosterone may act directly on MePD astrocytes to influence their structure and function. PMID:22581688

  7. Anti-Nogo-A Immunotherapy Does Not Alter Hippocampal Neurogenesis after Stroke in Adult Rats

    PubMed Central

    Shepherd, Daniel J.; Tsai, Shih-Yen; O'Brien, Timothy E.; Farrer, Robert G.; Kartje, Gwendolyn L.

    2016-01-01

    Ischemic stroke is a leading cause of adult disability, including cognitive impairment. Our laboratory has previously shown that treatment with function-blocking antibodies against the neurite growth inhibitory protein Nogo-A promotes functional recovery after stroke in adult and aged rats, including enhancing spatial memory performance, for which the hippocampus is critically important. Since spatial memory has been linked to hippocampal neurogenesis, we investigated whether anti-Nogo-A treatment increases hippocampal neurogenesis after stroke. Adult rats were subject to permanent middle cerebral artery occlusion followed 1 week later by 2 weeks of antibody treatment. Cellular proliferation in the dentate gyrus was quantified at the end of treatment, and the number of newborn neurons was determined at 8 weeks post-stroke. Treatment with both anti-Nogo-A and control antibodies stimulated the accumulation of new microglia/macrophages in the dentate granule cell layer, but neither treatment increased cellular proliferation or the number of newborn neurons above stroke-only levels. These results suggest that anti-Nogo-A immunotherapy does not increase post-stroke hippocampal neurogenesis. PMID:27803646

  8. Combined exposure to lead, inorganic mercury and methylmercury shows deviation from additivity for cardiovascular toxicity in rats.

    PubMed

    Wildemann, Tanja M; Weber, Lynn P; Siciliano, Steven D

    2015-08-01

    Environmental exposure to metal mixtures in the human population is common. Mixture risk assessments are often challenging because of a lack of suitable data on the relevant mixture. A growing number of studies show an association between lead or mercury exposure and cardiovascular effects. We investigated the cardiovascular effects of single metal exposure or co-exposure to methylmercury [MeHg(I)], inorganic mercury [Hg(II)] and lead [Pb(II)]. Male Wistar rats received four different metal mixtures for 28 days through the drinking water. The ratios of the metals were based on reference and environmental exposure values. Blood and pulse pressure, cardiac output and electrical activity of the heart were selected as end-points. While exposure to only MeHg(I) increased the systolic blood pressure and decreased cardiac output, the effects were reversed with combined exposures (antagonism). In contrast to these effects, combined exposures negatively affected the electrical activity of the heart (synergism). Thus, it appears that estimates of blood total Hg levels need to be paired with estimates of what species of mercury dominate exposure as well as whether lead co-exposure is present to link total blood Hg levels to cardiovascular effects. Based on current human exposure data and our results, there may be an increased risk of cardiac events as a result of combined exposures to Hg(II), MeHg(I) and Pb(II). This increased risk needs to be clarified by analyzing lead and Hg exposure data in relation to cardiac electrical activity in epidemiological studies.

  9. Behavioral effects of basal forebrain cholinergic lesions in young adult and aging rats.

    PubMed

    Paban, Véronique; Chambon, Caroline; Jaffard, Magali; Alescio-Lautier, Béatrice

    2005-08-01

    The interactive effects of age and cholinergic damage were assessed behaviorally in young and middle-aged rats. Rats were lesioned at either 3 or 17 months of age by injection of 192 IgG-saporin immunotoxin into the medial septum and the nucleus basalis magnocellularis, and they were then tested on a range of behavioral tasks: a nonmatching-to-position task in a T-maze, an object-recognition task, an object-location task, and an open-field activity test. Depending on the task used, only an age or a lesion effect was observed, but there was no Age X Lesion interaction. Middle-aged and young rats responded to the cholinergic lesions in the same manner. These results show that in the middle-aged rats in which cholinergic transmission was affected, additional injury to the system was not always accompanied by major cognitive dysfunctions. PMID:16187821

  10. Lifespan Changes in the Countermanding Performance of Young and Middle Aged Adult Rats

    PubMed Central

    Beuk, Jonathan; Beninger, Richard J.; Paré, Martin

    2016-01-01

    Inhibitory control can be investigated with the countermanding task, which requires subjects to make a response to a go signal and cancel that response when a stop signal is presented occasionally. Adult humans performing the countermanding task typically exhibit impaired response time (RT), stop signal response time (SSRT) and response accuracy as they get older, but little change in post-error slowing. Rodent models of the countermanding paradigm have been developed recently, yet none have directly examined age-related changes in performance throughout the lifespan. Male Wistar rats (N = 16) were trained to respond to a visual stimulus (go signal) by pressing a lever directly below an illuminated light for food reward, but to countermand the lever press subsequent to a tone (stop signal) that was presented occasionally (25% of trials) at a variable delay. Subjects were tested in 1 h sessions at approximately 7 and 12 months of age with intermittent training in between. Rats demonstrated longer go trial RT, a higher proportion of go trial errors and performed less total trials at 12, compared to 7 months of age. Consistent SSRT and post-error slowing were observed for rats at both ages. These results suggest that the countermanding performance of rats does vary throughout the lifespan, in a manner similar to humans, suggesting that rodents may provide a suitable model for behavioral impairment related to normal aging. These findings also highlight the importance of indicating the age at which rodents are tested in countermanding investigations. PMID:27555818

  11. Lifespan Changes in the Countermanding Performance of Young and Middle Aged Adult Rats.

    PubMed

    Beuk, Jonathan; Beninger, Richard J; Paré, Martin

    2016-01-01

    Inhibitory control can be investigated with the countermanding task, which requires subjects to make a response to a go signal and cancel that response when a stop signal is presented occasionally. Adult humans performing the countermanding task typically exhibit impaired response time (RT), stop signal response time (SSRT) and response accuracy as they get older, but little change in post-error slowing. Rodent models of the countermanding paradigm have been developed recently, yet none have directly examined age-related changes in performance throughout the lifespan. Male Wistar rats (N = 16) were trained to respond to a visual stimulus (go signal) by pressing a lever directly below an illuminated light for food reward, but to countermand the lever press subsequent to a tone (stop signal) that was presented occasionally (25% of trials) at a variable delay. Subjects were tested in 1 h sessions at approximately 7 and 12 months of age with intermittent training in between. Rats demonstrated longer go trial RT, a higher proportion of go trial errors and performed less total trials at 12, compared to 7 months of age. Consistent SSRT and post-error slowing were observed for rats at both ages. These results suggest that the countermanding performance of rats does vary throughout the lifespan, in a manner similar to humans, suggesting that rodents may provide a suitable model for behavioral impairment related to normal aging. These findings also highlight the importance of indicating the age at which rodents are tested in countermanding investigations. PMID:27555818

  12. Thymoquinone supplementation ameliorates lead-induced testis function impairment in adult rats.

    PubMed

    Mabrouk, Aymen; Ben Cheikh, Hassen

    2016-06-01

    This study was realized to investigate the possible beneficial effect of thymoquinone (TQ), the major active component of volatile oil of Nigella sativa seeds, against lead (Pb)-induced inhibition of rat testicular functions. Adult rats were randomized into four groups: a control group receiving no treatment; a Pb group exposed to 2000 parts per million (ppm) of Pb acetate in drinking water; a Pb-TQ group co-treated with Pb (as in Pb group) plus TQ (5 mg/kg body weight (b.w.)/day, per orally (p.o.)); and a TQ group receiving TQ (5 mg/kg b.w./day, p.o.). All treatments were for 5 weeks. No significant differences were observed for the body weight gain or for relative testes weight among the four groups of animals. Testicular Pb content significantly increased in metal-intoxicated rats compared with that in control rats. TQ supplementation had no effect on this testicular Pb accumulation. Interestingly, when coadministrated with Pb, TQ significantly improved the low plasma testosterone level and the decreased epididymal sperm count caused by Pb. In conclusion, the results suggest, for the first time, that TQ protects against Pb-induced impairment of testicular steroidogenic and spermatogenic functions. This study will open new perspectives for the clinical use of TQ in Pb intoxication.

  13. Tissue response of defined collagen-elastin scaffolds in young and adult rats with special attention to calcification.

    PubMed

    Daamen, W F; Nillesen, S T M; Hafmans, T; Veerkamp, J H; van Luyn, M J A; van Kuppevelt, T H

    2005-01-01

    Collagen-elastin scaffolds may be valuable biomaterials for tissue engineering because they combine tensile strength with elasticity. In this study, the tissue response to and the calcification of these scaffolds were evaluated. In particular, the hypothesis was tested that calcification, a common phenomenon in biomaterials, may be due to microfibrils within the elastic fibre, and that these microfibrils might generate a tissue response. Four scaffolds were subcutaneously implanted, viz. collagen, collagen + pure elastin, collagen+microfibril-containing, and collagen + pulverised elastic ligament (the source for elastin). Explants were evaluated at day 3, 7 and 21. In young Sprague Dawley rats, collagen + ligament calcified substantially, whereas collagen + elastin (with and without microfibrils) calcified less, and collagen did not. Calcification started at elastic fibres. In both Sprague Dawley and Wistar adult rats, however, none of the scaffolds calcified. Mononuclear cell infiltration was prominent in young and adult Sprague Dawley rats. In adult Wistar rats, this infiltration was associated with the presence of microfibrils. Degradation of scaffolds and new matrix formation were related with cellular influx and degree of vascularisation. In conclusion, absence of microfibrils from the elastic fibre does not prevent calcification in young Sprague Dawley rats, but does reduce the tissue response in adult Wistar rats. Cellular response and calcification differs with age and strain and therefore the choice of animal model is of key importance in biomaterial evaluation.

  14. Moderate prenatal alcohol exposure and quantification of social behavior in adult rats.

    PubMed

    Hamilton, Derek A; Magcalas, Christy M; Barto, Daniel; Bird, Clark W; Rodriguez, Carlos I; Fink, Brandi C; Pellis, Sergio M; Davies, Suzy; Savage, Daniel D

    2014-01-01

    Alterations in social behavior are among the major negative consequences observed in children with Fetal Alcohol Spectrum Disorders (FASDs). Several independent laboratories have demonstrated robust alterations in the social behavior of rodents exposed to alcohol during brain development across a wide range of exposure durations, timing, doses, and ages at the time of behavioral quantification. Prior work from this laboratory has identified reliable alterations in specific forms of social interaction following moderate prenatal alcohol exposure (PAE) in the rat that persist well into adulthood, including increased wrestling and decreased investigation. These behavioral alterations have been useful in identifying neural circuits altered by moderate PAE(1), and may hold importance for progressing toward a more complete understanding of the neural bases of PAE-related alterations in social behavior. This paper describes procedures for performing moderate PAE in which rat dams voluntarily consume ethanol or saccharin (control) throughout gestation, and measurement of social behaviors in adult offspring. PMID:25549080

  15. The 14-day repeated dose liver micronucleus test with methapyrilene hydrochloride using young adult rats.

    PubMed

    Inoue, Kenji; Ochi, Akimu; Koda, Akira; Wako, Yumi; Kawasako, Kazufumi; Doi, Takaaki

    2015-03-01

    The repeated dose liver micronucleus (RDLMN) assay using young adult rats has the potential to detect genotoxic hepatocarcinogens that can be integrated into a general toxicity study. The assay methods were thoroughly validated by 19 Japanese facilities. Methapyrilene hydrochloride (MP), known to be a non-genotoxic hepatocarcinogen, was examined in the present study. MP was dosed orally at 10, 30 and 100mg/kg/day to 6-week-old male Crl:CD (SD) rats daily for 14 days. Treatment with MP resulted in an increase in micronucleated hepatocytes (MNHEPs) with a dosage of only 100mg/kg/day. At this dose level, cytotoxicity followed by regenerative cell growth was noted in the liver. These findings suggest that MP may induce clastogenic effects indirectly on the liver or hepatotoxicity of MP followed by regeneration may cause increase in spontaneous incidence of MNHEPs.

  16. Functional evidence of α1D-adrenoceptors in the vasculature of young and adult spontaneously hypertensive rats

    PubMed Central

    Villalobos-Molina, Rafael; López-Guerrero, J Javier; Ibarra, Maximiliano

    1999-01-01

    The role of α1D-adrenoceptors in the vasculature of spontaneously hypertensive (SHR) and normotensive Wistar Kyoto rats (WKY), of different ages was assessed in pithed rats by the use of the selective α1D-adrenoceptor antagonist BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]-ethyl]-8-azaspiro [4.5]decane-7,9-dione dihydrochloride). BMY 7378 displaced the pressor effect of phenylephrine in young pre-hypertensive pithed SHR rats, but produced no effect in young WKY rats (dose ratio of 3.4 and 1.6, respectively), while in adult rats BMY 7378 produced a greater shift in the phenylephrine response curve than in younger animals (dose ratio of 3.2 and 6.2 in WKY and SHR, respectively). The presence of α1D-adrenoceptors in the vasculature of pre-hypertensive rats, suggests its role in the pathogenesis/maintenance of increased blood pressure. PMID:10323583

  17. Functional evidence of alpha1D-adrenoceptors in the vasculature of young and adult spontaneously hypertensive rats.

    PubMed

    Villalobos-Molina, R; López-Guerrero, J J; Ibarra, M

    1999-04-01

    The role of alpha1D-adrenoceptors in the vasculature of spontaneously hypertensive (SHR) and normotensive Wistar Kyoto rats (WKY), of different ages was assessed in pithed rats by the use of the selective alpha1D-adrenoceptor antagonist BMY 7378 (8-[2-[4-(2-methoxyphenyl)-1-piperazinyl]-ethyl]-8-azaspiro [4.5]decane-7,9-dione dihydrochloride). BMY 7378 displaced the pressor effect of phenylephrine in young pre-hypertensive pithed SHR rats, but produced no effect in young WKY rats (dose ratio of 3.4 and 1.6, respectively), while in adult rats BMY 7378 produced a greater shift in the phenylephrine response curve than in younger animals (dose ratio of 3.2 and 6.2 in WKY and SHR, respectively). The presence of alpha1D-adrenoceptors in the vasculature of pre-hypertensive rats, suggests its role in the pathogenesis/maintenance of increased blood pressure. PMID:10323583

  18. Stretch induced endothelin-1 secretion by adult rat astrocytes involves calcium influx via stretch-activated ion channels (SACs)

    SciTech Connect

    Ostrow, Lyle W.; Suchyna, Thomas M.; Sachs, Frederick

    2011-06-24

    Highlights: {yields} Endothelin-1 expression by adult rat astrocytes correlates with cell proliferation. {yields} Stretch-induced ET-1 is inhibited by GsMtx-4, a specific inhibitor of Ca{sup 2+} permeant SACs. {yields} The less specific SAC inhibitor streptomycin also inhibits ET-1 secretion. {yields} Stretch-induced ET-1 production depends on a calcium influx. {yields} SAC pharmacology may provide a new class of therapeutic agents for CNS pathology. -- Abstract: The expression of endothelins (ETs) and ET-receptors is often upregulated in brain pathology. ET-1, a potent vasoconstrictor, also inhibits the expression of astrocyte glutamate transporters and is mitogenic for astrocytes, glioma cells, neurons, and brain capillary endothelia. We have previously shown that mechanical stress stimulates ET-1 production by adult rat astrocytes. We now show in adult astrocytes that ET-1 production is driven by calcium influx through stretch-activated ion channels (SACs) and the ET-1 production correlates with cell proliferation. Mechanical stimulation using biaxial stretch (<20%) of a rubber substrate increased ET-1 secretion, and 4 {mu}M GsMTx-4 (a specific inhibitor of SACs) inhibited secretion by 30%. GsMTx-4 did not alter basal ET-1 levels in the absence of stretch. Decreasing the calcium influx by lowering extracellular calcium also inhibited stretch-induced ET-1 secretion without effecting ET-1 secretion in unstretched controls. Furthermore, inhibiting SACs with the less specific inhibitor streptomycin also inhibited stretch-induced ET-1 secretion. The data can be explained with a simple model in which ET-1 secretion depends on an internal Ca{sup 2+} threshold. This coupling of mechanical stress to the astrocyte endothelin system through SACs has treatment implications, since all pathology deforms the surrounding parenchyma.

  19. Intestinal mast cells and eosinophils in relation to Strongyloides ratti adult expulsion from the small and large intestines of rats.

    PubMed

    Shintoku, Y; Kadosaka, T; Kimura, E; Takagi, H; Kondo, S; Itoh, M

    2013-04-01

    Mucosal mast cells (MMC) play a crucial role in the expulsion of Strongyloides ratti adults from the small intestine of mice. We reported the large intestinal parasitism of S. ratti in rats, and there has been no report on MMC in the large intestine of the natural host. We studied kinetics of MMC, together with eosinophils, in the upper and lower small intestines, caecum and colon of infected rats. Two distinct phases of mastocytosis were revealed: one in the upper small intestine triggered by stimulation of 'ordinary' adults, and the other in the colon stimulated by 'immune-resistant' adults that started parasitizing the colon around 19 days post-infection. In all 4 intestinal sites, the MMC peaks were observed 5-7 days after the number of adult worms became the maximum and the height of MMC peaks appeared to be dependent on the number of parasitic adults, suggesting an important role played by worms themselves in the MMC buildup.

  20. Effect of chronic hyperoxic exposure on duroquinone reduction in adult rat lungs.

    PubMed

    Audi, Said H; Bongard, Robert D; Krenz, Gary S; Rickaby, David A; Haworth, Steven T; Eisenhauer, Jessica; Roerig, David L; Merker, Marilyn P

    2005-11-01

    NAD(P)H:quinone oxidoreductase 1 (NQO1) plays a dominant role in the reduction of the quinone compound 2,3,5,6-tetramethyl-1,4-benzoquinone (duroquinone, DQ) to durohydroquinone (DQH2) on passage through the rat lung. Exposure of adult rats to 85% O2 for > or =7 days stimulates adaptation to the otherwise lethal effects of >95% O2. The objective of this study was to examine whether exposure of adult rats to hyperoxia affected lung NQO1 activity as measured by the rate of DQ reduction on passage through the lung. We measured DQH2 appearance in the venous effluent during DQ infusion at different concentrations into the pulmonary artery of isolated perfused lungs from rats exposed to room air or to 85% O2. We also evaluated the effect of hyperoxia on vascular transit time distribution and measured NQO1 activity and protein in lung homogenate. The results demonstrate that exposure to 85% O2 for 21 days increases lung capacity to reduce DQ to DQH2 and that NQO1 is the dominant DQ reductase in normoxic and hyperoxic lungs. Kinetic analysis revealed that 21-day hyperoxia exposure increased the maximum rate of pulmonary DQ reduction, Vmax, and the apparent Michaelis-Menten constant for DQ reduction, Kma. The increase in Vmax suggests a hyperoxia-induced increase in NQO1 activity of lung cells accessible to DQ from the vascular region, consistent qualitatively but not quantitatively with an increase in lung homogenate NQO1 activity in 21-day hyperoxic lungs. The increase in Kma could be accounted for by approximately 40% increase in vascular transit time heterogeneity in 21-day hyperoxic lungs.

  1. Site- and compartment-specific changes in bone with hindlimb unloading in mature adult rats

    NASA Technical Reports Server (NTRS)

    Bloomfield, S. A.; Allen, M. R.; Hogan, H. A.; Delp, M. D.

    2002-01-01

    The purpose of this study was to examine site- and compartment-specific changes in bone induced by hindlimb unloading (HU) in the mature adult male rat (6 months old). Tibiae, femora, and humeri were removed after 14, 21, and 28 days of HU for determination of bone mineral density (BMD) and geometry by peripheral quantitative computed tomography (pQCT), mechanical properties, and bone formation rate (BFR), and compared with baseline (0 day) and aging (28 day) controls. HU resulted in 20%-21% declines in cancellous BMD at the proximal tibia and femoral neck after 28 day HU vs. 0 day controls (CON). Cortical shell BMD at these sites was greater (by 4%-6%) in both 28 day HU and 28 day CON vs. 0 day CON animals, and nearly identical to that gain seen in the weight-bearing humerus. Mechanical properties at the proximal tibia exhibited a nonsignificant decline after HU vs. those of 0 day CON rats. At the femoral neck, a 10% decrement was noted in ultimate load in 28 day HU rats vs. 28 day CON animals. Middiaphyseal tibial bone increased slightly in density and area during HU; no differences in structural and material properties between 28 day HU and 28 day CON rats were noted. BFR at the tibial midshaft was significantly lower (by 90%) after 21 day HU vs. 0 day CON; this decline was maintained throughout 28 day HU. These results suggest there are compartment-specific differences in the mature adult skeletal response to hindlimb unloading, and that the major impact over 28 days of unloading is on cancellous bone sites. Given the sharp decline in BFR for midshaft cortical bone, it appears likely that deficits in BMD, area, or mechanical properties would develop with longer duration unloading.

  2. Repeated Ketamine Exposure Induces an Enduring Resilient Phenotype in Adolescent and Adult Rats

    PubMed Central

    Parise, Eric M.; Alcantara, Lyonna F.; Warren, Brandon L.; Wright, Katherine N.; Hadad, Roey; Sial, Omar K.; Kroeck, Kyle G.; Iñiguez, Sergio D.; Bolaños-Guzmán, Carlos A.

    2013-01-01

    Background Major Depressive Disorder (MDD) afflicts up to 10% of adolescents. However, nearly 50% of those afflicted are considered non-responsive to available treatments. Ketamine, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist has shown potential as a rapid-acting and long-lasting treatment for MDD in adults. Thus, the effectiveness and functional consequences of ketamine exposure during adolescence were explored. Methods Adolescent male rats (postnatal day [PD] 35) received two ketamine (0, 5, 10 or 20 mg/kg) injections, 4 hours apart, after exposure to day 1 of the forced swim test (FST). The next day, rats were re-exposed to the FST to assess ketamine-induced antidepressant-like responses. Separate groups were exposed to chronic unpredictable stress (CUS) to confirm findings from the FST. After these initial experiments, adolescent naïve rats were exposed to either 1 or 15 consecutive days (PD35–49) of ketamine (20 mg/kg) twice/daily. Ketamine's influence on behavioral reactivity to rewarding (i.e., sucrose preference) and aversive (i.e., elevated plus-maze, FST) circumstances was then assessed 2 months after treatment. To control for age-dependent effects, adult rats (PD75–89) were exposed to identical experimental conditions. Results Ketamine (20 mg/kg) reversed the CUS-induced depression-like behaviors in the FST. Repeated ketamine exposure resulted in anxiolytic- and antidepressant-like responses 2 months after drug exposure. None of the ketamine doses used were capable of inducing drug-seeking behaviors as measured by place preference conditioning. Conclusions Repeated ketamine exposure induces enduring resilient-like responses regardless of age of exposure. These findings point to ketamine, and its repeated exposure, as a potentially useful antidepressant during adolescence. PMID:23790225

  3. Comparative analysis of antioxidants against cadmium induced reproductive toxicity in adult male rats.

    PubMed

    Jahan, Sarwat; Khan, Mehreen; Ahmed, Shakeel; Ullah, Hizb

    2014-02-01

    The present study was conducted to compare and evaluate the potential benefits of three different antioxidants in reversing cadmium (Cd)-induced reproductive toxicity in adult male rats. Rats (n = 5) weighing 180 +/- 20 gm were divided into five groups (control, Cd, Cd + sulforaphane, Cd + vitamin E, and Cd + plant extract). Treated groups received CdCl2 (0.2 mg/kg), sulforaphane (25 µg/rat), vitamin E (75 mg/kg), and plant extract (100 mg/kg) for 15 days. Blood samples and testicular tissues were obtained for estimation of testosterone, Zn, and Cd concentration and daily sperm production/efficiency of sperm production. Cadmium exposure caused a significant decrease in final body weight (p < 0.0001). The plasma concentrations of Cd were significantly increased and Zn concentration decreased (p < 0.0001) in the Cd group as compared to the control group. The testicular concentrations of Cd were significantly increased and Zn concentration decreased (p < 0.0001) in the Cd group as compared to the control group. Cadmium exposure caused a significant decrease (p < 0.0001) in plasma testosterone concentrations and daily sperm production as compared to the control group. More significant effects were observed with Cd+sulforaphane, Cd + vitamin E, and Cd + plant extract treated groups in slashing Cd-induced toxicity. Present findings suggest that Ficus religiosa and sulforaphane are more powerful antioxidants as compared to vitamin E in reversing the oxidative stress and can have a protective role against Cd induced reproductive toxicity in adult male rats. Part of the mechanism involved in this protective role seems to be associated with the antioxidant properties of these agents in reducing reproductive damage. PMID:24156729

  4. Effect of agomelatine on adult hippocampus apoptosis and neurogenesis using the stress model of rats.

    PubMed

    Yucel, Atakan; Yucel, Nermin; Ozkanlar, Seckin; Polat, Elif; Kara, Adem; Ozcan, Halil; Gulec, Mustafa

    2016-04-01

    Agomelatine (AG) is an agonist of melatonin receptors and an antagonist of the 5-HT2C-receptor subtype. The chronobiotic properties of AG are of significant interest due to the disorganization of internal rhythms, which might play a role in the pathophysiology of depression. The present study was designed to assess the effects of the antidepressant-like activity of AG, a new antidepressant drug, on adult neurogenesis and apoptosis using stress-exposed rat brains. Over the period of 1 week, the rats were exposed to light stress twice a day for 1h. After a period of 1 week, the rats were given AG treatment at a dose of either 10mg/kg or 40mg/kg for 15 days. The animals were then scarified, and the obtained tissue sections were stained with immuno-histochemical anti-BrdU, Caspase-3, and Bcl-2 antibodies. Serum brain-derived neurotrophic factor (BDNF) concentrations were measured biochemically using a BDNF Elisa kit. Biochemical BDNF analysis revealed a high concentration of BDNF in the serum of the stress-exposed group, but the concentrations of BDNF were much lower those of the AG-treated groups. Immuno-histochemical analysis revealed that AG treatment decreased the BrdU-positive and Bcl-2-positive cell densities and increased the Caspase-3-positive cell density in the hippocampus of stress-induced rats as compared to those of the stress group. The results of the study demonstrated that AG treatment ameliorated the hippocampal apoptotic cells and increased hippocampal neurogenesis. These results also strengthen the possible relationship between depression and adult neurogenesis, which must be studied further.

  5. Effect of agomelatine on adult hippocampus apoptosis and neurogenesis using the stress model of rats.

    PubMed

    Yucel, Atakan; Yucel, Nermin; Ozkanlar, Seckin; Polat, Elif; Kara, Adem; Ozcan, Halil; Gulec, Mustafa

    2016-04-01

    Agomelatine (AG) is an agonist of melatonin receptors and an antagonist of the 5-HT2C-receptor subtype. The chronobiotic properties of AG are of significant interest due to the disorganization of internal rhythms, which might play a role in the pathophysiology of depression. The present study was designed to assess the effects of the antidepressant-like activity of AG, a new antidepressant drug, on adult neurogenesis and apoptosis using stress-exposed rat brains. Over the period of 1 week, the rats were exposed to light stress twice a day for 1h. After a period of 1 week, the rats were given AG treatment at a dose of either 10mg/kg or 40mg/kg for 15 days. The animals were then scarified, and the obtained tissue sections were stained with immuno-histochemical anti-BrdU, Caspase-3, and Bcl-2 antibodies. Serum brain-derived neurotrophic factor (BDNF) concentrations were measured biochemically using a BDNF Elisa kit. Biochemical BDNF analysis revealed a high concentration of BDNF in the serum of the stress-exposed group, but the concentrations of BDNF were much lower those of the AG-treated groups. Immuno-histochemical analysis revealed that AG treatment decreased the BrdU-positive and Bcl-2-positive cell densities and increased the Caspase-3-positive cell density in the hippocampus of stress-induced rats as compared to those of the stress group. The results of the study demonstrated that AG treatment ameliorated the hippocampal apoptotic cells and increased hippocampal neurogenesis. These results also strengthen the possible relationship between depression and adult neurogenesis, which must be studied further. PMID:26970810

  6. A comparison of adult and adolescent rat behavior in operant learning, extinction, and behavioral inhibition paradigms.

    PubMed

    Andrzejewski, Matthew E; Schochet, Terri L; Feit, Elizabeth C; Harris, Rachel; McKee, Brenda L; Kelley, Ann E

    2011-02-01

    Poor self-control, lack of inhibition, and impulsivity contribute to the propensity of adolescents to engage in risky or dangerous behaviors. Brain regions (e.g., prefrontal cortex) involved in impulse-control, reward-processing, and decision-making continue to develop during adolescence, raising the possibility that an immature brain contributes to dangerous behavior during adolescence. However, very few validated animal behavioral models are available for behavioral neuroscientists to explore the relationship between brain development and behavior. To that end, a valid model must be conducted in the relatively brief window of adolescence and not use manipulations that potentially compromise development. The present experiments used three operant arrangements to assess whether adolescent rats differ from adults in measures of learning, behavioral inhibition, and impulsivity, within the aforementioned time frame without substantial food restriction. In Experiment 1, separate squads of rats were trained to lever-press and then transitioned to two types of extinction. Relative to their baselines, adolescent rats responded more during extinction than adults, suggesting that they were less sensitive to the abolishment of the reinforcement contingency. Experiment 2 demonstrated similar age-related differences during exposure to a differential reinforcement of low rates schedule, a test of behavioral inhibition. Lastly, in Experiment 3, adolescent's responding decreased more slowly than adults during exposure to a resetting delay of reinforcement schedule, suggesting impaired self-control. Results from these experiments suggest that adolescents exhibit impaired learning, behavioral inhibition and self-control, and in concert with recent reports, provide researchers with three behavioral models to more fully explore neurobiology of risk-taking behavior in adolescence.

  7. Increased excitability and molecular changes in adult rats after a febrile seizure.

    PubMed

    Reid, Aylin Y; Riazi, Kiarash; Campbell Teskey, G; Pittman, Quentin J

    2013-04-01

    Both early life inflammation and prolonged febrile seizures have been associated with increased excitation in the adult brain. We hypothesized this may be due in part to changes in the cation-chloride cotransporter system. Rat pups received saline or lipopolysaccharide/kainic acid (LPS/KA) resulting in inflammation, followed by a behavioral febrile seizure (FS) in approximately 50% of rats. Adult animals from the saline, inflammation, or inflammation + FS groups underwent the following: (1) in vitro electrophysiologic studies; (2) Western blotting or polymerase chain reaction; or (3) application of the Na-K-Cl cotransporter 1 (NKCC1) blocker bumetanide to determine its effect on reversing increased excitability in vitro. The inflammation and inflammation + FS groups demonstrated increased excitability in vitro and increased hippocampal protein expression of NR2B and GABAA α5 receptor subunits and mRNA expression of NKCC1. The inflammation + FS group also had decreased protein expression of GluR2 and GABAA α1 receptor subunits and mRNA and protein expression of KCC2. Bumetanide decreased in vitro 4-aminopyridine-induced inter-ictal activity in the inflammation and inflammation + FS groups. The results demonstrate early-life inflammation with or without a behavioral FS can lead to long-lasting molecular changes and increased excitability in the adult rat hippocampus, although some changes are more extensive when inflammation is accompanied by behavioral seizure activity. Bumetanide is effective in reversing increased excitability in vitro, providing evidence for a causal role for cation-chloride cotransporters and suggesting this drug may prove useful for treating epilepsy that develops after a FS. PMID:23293960

  8. Testosterone depletion in adult male rats increases mossy fiber transmission, LTP, and sprouting in area CA3 of hippocampus

    PubMed Central

    Skucas, Vanessa A.; Duffy, Aine M.; Harte-Hargrove, Lauren; Magagna-Poveda, Alejandra; Radman, Thomas; Chakraborty, Goutam; Schroeder, Charles E.; MacLusky, Neil J.; Scharfman, H.E.

    2013-01-01

    Androgens have dramatic effects on neuronal structure and function in hippocampus. However, androgen depletion does not always lead to hippocampal impairment. To address this apparent paradox, we evaluated the hippocampus of adult male rats after gonadectomy (Gdx) or sham surgery. Surprisingly, Gdx rats showed increased synaptic transmission and long-term potentiation (LTP) of the mossy fiber (MF) pathway. Gdx rats also exhibited increased excitability and MF sprouting. We then addressed the possible underlying mechanisms, and found that Gdx induced a long-lasting upregulation of MF brain-derived neurotrophic factor (BDNF) immunoreactivity. Antagonism of Trk receptors, which bind neurotrophins such as BDNF, reversed the increase in MF transmission, excitability and LTP in Gdx rats, but there were no effects of Trk antagonism in sham controls. To determine which androgens were responsible, the effects of testosterone metabolites dihydrotestosterone (DHT) and 5α-androstane-3α,17β-diol were examined. Exposure of slices to 50 nM DHT decreased the effects of Gdx on MF transmission but 50 nM 5α-androstane-3α,17β-diol had no effect. Remarkably, there was no effect of DHT in control males. The data suggest that a Trk- and androgen receptor-sensitive form of MF transmission and synaptic plasticity emerges after Gdx. We suggest that androgens may normally be important in area CA3 to prevent hyperexcitability and aberrant axon outgrowth, but limit MF synaptic transmission and some forms of plasticity. The results also suggest a potential explanation for the maintenance of hippocampal-dependent cognitive function after androgen depletion: a reduction in androgens may lead to compensatory upregulation of MF transmission and plasticity. PMID:23392664

  9. Whisker motor cortex reorganization after superior colliculus output suppression in adult rats.

    PubMed

    Veronesi, Carlo; Maggiolini, Emma; Franchi, Gianfranco

    2013-10-01

    The effect of unilateral superior colliculus (SC) output suppression on the ipsilateral whisker motor cortex (WMC) was studied at different time points after tetrodotoxin and quinolinic acid injections, in adult rats. The WMC output was assessed by mapping the movement evoked by intracortical microstimulation (ICMS) and by recording the ICMS-evoked electromyographic (EMG) responses from contralateral whisker muscles. At 1 h after SC injections, the WMC showed: (i) a strong decrease in contralateral whisker sites, (ii) a strong increase in ipsilateral whisker sites and in ineffective sites, and (iii) a strong increase in threshold current values. At 6 h after injections, the WMC size had shrunk to 60% of the control value and forelimb representation had expanded into the lateral part of the normal WMC. Thereafter, the size of the WMC recovered, returning to nearly normal 12 h later (94% of control) and persisted unchanged over time (1-3 weeks). The ICMS-evoked EMG response area decreased at 1 h after SC lesion and had recovered its baseline value 12 h later. Conversely, the latency of ICMS-evoked EMG responses had increased by 1 h and continued to increase for as long as 3 weeks following the lesion. These findings provide physiological evidence that SC output suppression persistently withdrew the direct excitatory drive from whisker motoneurons and induced changes in the WMC. We suggest that the changes in the WMC are a form of reversible short-term reorganization that is induced by SC lesion. The persistent latency increase in the ICMS-evoked EMG response suggested that the recovery of basic WMC excitability did not take place with the recovery of normal explorative behaviour. PMID:23895333

  10. Aberrant NMDA-dependent LTD after perinatal ethanol exposure in young adult rat hippocampus.

    PubMed

    Kervern, Myriam; Silvestre de Ferron, Benoît; Alaux-Cantin, Stéphanie; Fedorenko, Olena; Antol, Johann; Naassila, Mickael; Pierrefiche, Olivier

    2015-08-01

    Irreversible cognitive deficits induced by ethanol exposure during fetal life have been ascribed to a lower NMDA-dependent synaptic long-term potentiation (LTP) in the hippocampus. Whether NMDA-dependent long-term depression (LTD) may also play a critical role in those deficits remains unknown. Here, we show that in vitro LTD induced with paired-pulse low frequency stimulation is enhanced in CA1 hippocampus field of young adult rats exposed to ethanol during brain development. Furthermore, single pulse low frequency stimulation, ineffective at this age (LFS600), induced LTD after ethanol exposure accompanied with a stronger response than controls during LFS600, thus revealing an aberrant form of activity-dependent plasticity at this age. Blocking NMDA receptor or GluN2B containing NMDA receptor prevented both the stronger response during LFS600 and LTD whereas Zinc, an antagonist of GluN2A containing NMDA receptor, was ineffective on both responses. In addition, LFS600-induced LTD was revealed in controls only with a reduced-Mg(2+) medium. In whole dissected hippocampus CA1 field, perinatal ethanol exposure increased GluN2B subunit expression in the synaptic compartment whereas GluN2A was unaltered. Using pharmacological tools, we suggest that LFS600 LTD was of synaptic origin. Altogether, we describe a new mechanism by which ethanol exposure during fetal life induces a long-term alteration of synaptic plasticity involving NMDA receptors, leading to an aberrant LTD. We suggest this effect of ethanol may reflect a delayed maturation of the synapse and that aberrant LTD may also participates to long-lasting cognitive deficits in fetal alcohol spectrum disorder.

  11. The effects of prenatal PCBs on adult social behavior in rats.

    PubMed

    Reilly, Michael P; Weeks, Connor D; Topper, Viktoria Y; Thompson, Lindsay M; Crews, David; Gore, Andrea C

    2015-07-01

    Endocrine disrupting chemical (EDC) exposures during critical periods of development may influence neuronal development and the manifestation of sexually dimorphic sociability and social novelty behaviors in adulthood. In this study, we assessed the effects of gestational exposure to PCBs on the social behavior of males and females later in adulthood. A weakly estrogenic PCB mixture, Aroclor 1221 (A1221, 0.5 or 1mg/kg) was administered to pregnant Sprague-Dawley rat dams. Both a positive control (estradiol benzoate; EB, 50μg/kg) and negative control (dimethylsulfoxide; DMSO in sesame oil vehicle) were similarly administered to separate sets of dams. The sexes responded differently in two tasks essential to sociality. Using a three-chamber apparatus that contained a caged, same-sex, gonadectomized stimulus animal and an empty stimulus cage, we found that both sexes showed a strong preference for affiliating with a stimulus animal (vs. an empty cage), an effect that was much more pronounced in the males. In the second task, a novel and a familiar stimulus animal were caged at opposite ends of the same apparatus. Females displayed a higher degree of novelty preference than the males. During both tests, females had significantly higher social approach behaviors while male engaged in significantly more interactive behaviors with the conspecific. Of particular interest, males born of dams that received prenatal A1221 (0.5mg/kg) exhibited an overall decrease in nose-to-nose investigations. These behavioral data suggest that the males are more sensitive to A1221 treatment than are females. In addition to behavioral analysis, serum corticosterone was measured. Females born of dams treated with A1221 (0.5mg/kg) had significantly higher concentrations of corticosterone than the DMSO female group; males were unaffected. Females also had significantly higher corticosterone concentrations than did males. Overall, our results suggest that the effects of gestational exposure to

  12. The effects of prenatal PCBs on adult social behavior in rats

    PubMed Central

    Reilly, Michael P.; Weeks, Connor D.; Topper, Viktoria Y.; Thompson, Lindsay M.; Crews, David; Gore, Andrea C.

    2015-01-01

    Endocrine disrupting chemical (EDC) exposures during critical periods of development may influence neuronal development and the manifestation of sexually dimorphic sociability and social novelty behaviors in adulthood. In this study, we assessed the effects of gestational exposure to PCBs on the social behavior of males and females later in adulthood. A weakly estrogenic PCB mixture, Aroclor 1221 (A1221, 0.5 or 1 mg/kg) was administered to pregnant Sprague-Dawley rat dams. Both a positive control (estradiol benzoate; EB, 50 μg/kg) and negative control (dimethylsulfoxide; DMSO in sesame oil vehicle) were similarly administered to separate sets of dams. The sexes responded differently in two tasks essential to sociality. Using a three-chamber apparatus that contained a caged, same-sex, gonadectomized stimulus animal and an empty stimulus cage, we found that both sexes showed a strong preference for affiliating with a stimulus animal (vs. an empty cage), an effect that was much more pronounced in the males. In the second task, a novel and a familiar stimulus animal were caged at opposite ends of the same apparatus. Females displayed a higher degree of novelty preference than the males. During both tests, females had significantly higher social approach behaviors while male engaged in significantly more interactive behaviors with the conspecific. Of particular interest, males born of dams that received prenatal A1221 (0.5 mg/kg) exhibited an overall decrease in nose-to-nose investigations. These behavioral data suggest that the males are more sensitive to A1221 treatment than are females. In addition to behavioral analysis, serum corticosterone was measured. Females born of dams treated with A1221 (0.5 mg/kg) had significantly higher concentrations of corticosterone than the DMSO female group; males were unaffected. Females also had significantly higher corticosterone concentrations than did males. Overall, our results suggest that the effects of gestational exposure

  13. Primary blast injury-induced lesions in the retina of adult rats

    PubMed Central

    2013-01-01

    Background The effect of primary blast exposure on the brain is widely reported but its effects on the eye remains unclear. Here, we aim to examine the effects of primary blast exposure on the retina. Methods Adult male Sprague–Dawley rats were exposed to primary blast high and low injury and sacrificed at 24 h, 72 h, and 2 weeks post injury. The retina was subjected to western analysis for vascular endothelial growth factor (VEGF), aquaporin-4 (AQP4), glutamine synthethase (GS), inducible nitric oxide synthase (NOS), endothelial NOS, neuronal NOS and nestin expression; ELISA analysis for cytokines and chemokines; and immunofluorescence for glial fibrillary acidic protein (GFAP)/VEGF, GFAP/AQP4, GFAP/nestin, GS/AQP4, lectin/iNOS, and TUNEL. Results The retina showed a blast severity-dependent increase in VEGF, iNOS, eNOS, nNOS, and nestin expression with corresponding increases in inflammatory cytokines and chemokines. There was also increased AQP4 expression and retinal thickness after primary blast exposure that was severity-dependent. Finally, a significant increase in TUNEL+ and Caspase-3+ cells was observed. These changes were observed at 24 h post-injury and sustained up to 2 weeks post injury. Conclusions Primary blast resulted in severity-dependent pathological changes in the retina, manifested by the increased expression of a variety of proteins involved in inflammation, edema, and apoptosis. These changes were observed immediately after blast exposure and sustained up to 2 weeks suggesting acute and chronic injury mechanisms. These changes were most obvious in the astrocytes and Müller cells and suggest important roles for these cells in retina pathophysiology after blast. PMID:23819902

  14. Maternal separation stress leads to enhanced emotional responses to noxious stimuli in adult rats.

    PubMed

    Uhelski, Megan L; Fuchs, Perry N

    2010-10-15

    The purpose of the current study was to examine pain processing in adult rats following repeated maternal separation in infancy, a common model of early life stress. Sensory pain processing remained unaltered, as measured using threshold testing of nociception. However, affective pain processing was enhanced as revealed by increased responding during the tonic phase of the formalin test and during the place escape/avoidance test. The pattern of enhanced responses suggests that early life stress alters the emotional response to pain. Further research could determine if this pattern holds true for different pain models, or if post-weaning enrichment could reverse the effects of maternal separation on pain processing.

  15. Impairment on sperm quality and fertility of adult rats after antiandrogen exposure during prepuberty.

    PubMed

    Perobelli, Juliana Elaine; Alves, Thaís Regina; de Toledo, Fabíola Choqueta; Fernandez, Carla Dal Bianco; Anselmo-Franci, Janete A; Klinefelter, Gary R; Kempinas, Wilma De Grava

    2012-06-01

    This study evaluated the effects of antiandrogen exposure during the prepubertal period on reproductive development and reproductive competence in adults. Male rats were divided into two groups: flutamide, receiving 25 mg/kg/day of flutamide by oral gavage and control, receiving vehicle daily. Dosing continued from PND 21 to 44, and animals were killed on PND 50 or PND 75-80. The epididymis, prostate, vas deferens and seminal vesicle weights were lower in Flutamide group on PND 50, while on PND 80 only seminal vesicle weight was reduced. Fertility assessed by IUI revealed a decrease in the fertility potential in the flutamide-treated adults. Flutamide accelerated sperm transit time through the epididymis, impairing sperm motility and storage. A quantitative analysis of the cauda sperm membrane proteome revealed a few significant changes in protein expression. Thus, exposure to flutamide during the prepubertal period compromises the function of the epididymis along with epididymal sperm quality at adulthood.

  16. The effects of running and of inhibiting adult neurogenesis on learning and memory in rats.

    PubMed

    Wojtowicz, J Martin; Askew, Michele L; Winocur, Gordon

    2008-03-01

    The presence of ongoing adult neurogenesis within the highly plastic hippocampal circuitry poses questions as to the relevance of new neurons to learning and memory. Correlational and causal evidence suggests that some, but not all, hippocampal tasks involve the new neurons. The evidence with regard to spatial learning in the water maze, one of the most commonly used hippocampal tasks, is contradictory. In this study we examined the effects of irradiation-induced reduction in neurogenesis on spatial learning and another standard hippocampal task, contextual fear conditioning, in rats that experienced normal cage conditions or voluntary running. The results indicate that reduced neurogenesis had little effect on spatial learning but severely impaired contextual fear conditioning. It was suggested that compensatory mechanisms within the hippocampus may have contributed selectively to sparing of spatial function. Performance on the fear conditioning task was weakly related to enhanced neurogenesis or running. The results improve our understanding of the functional role of adult neurogenesis in behaving animals.

  17. Rats markedly escalate their intake and show a persistent susceptibility to reinstatement only when cocaine is injected rapidly.

    PubMed

    Wakabayashi, Ken T; Weiss, Mark J; Pickup, Kristen N; Robinson, Terry E

    2010-08-25

    When drugs enter the brain rapidly, liability for addiction is increased, but why this is the case is not well understood. Here we examined the influence of varying the speed of intravenous cocaine delivery on self-administration behavior in rats given limited or extended opportunity to take drug. The speed of cocaine delivery had no effect on self-administration behavior when rats were given only 1 h each day to take cocaine. When given sixfold more time to take cocaine, rats that received cocaine rapidly (5-45 s) increased their total intake eightfold. However, rats that received cocaine more slowly (>90 s) did not avail themselves of the opportunity to take much more drug: they increased their intake only twofold. Furthermore, when tested 45 d after the last self-administration session, a drug-priming injection reinstated drug-seeking behavior only in rats that in the past had cocaine injected rapidly (5 s), and this was associated with a persistent suppression in the ability of cocaine to induce immediate early gene expression. Cocaine may be potentially more addictive when it reaches the brain rapidly because (1) this promotes a marked escalation in intake and (2) it renders individuals more susceptible to relapse long after the discontinuation of drug use. This is presumably because the rapid uptake of drug to the brain preferentially promotes persistent changes in brain systems that regulate motivation for drug, and continuing exposure to large amounts of drug produces a vicious cycle of additional maladaptive changes in brain and behavior.

  18. Stress-induced oxytocin release and oxytocin cell number and size in prepubertal and adult male and female rats.

    PubMed

    Minhas, Sumeet; Liu, Clarissa; Galdamez, Josselyn; So, Veronica M; Romeo, Russell D

    2016-08-01

    Studies indicate that adolescent exposure to stress is a potent environmental factor that contributes to psychological and physiological disorders, though the mechanisms that mediate these dysfunctions are not well understood. Periadolescent animals display greater stress-induced hypothalamic-pituitary-adrenal (HPA) axis responses than adults, which may contribute to these vulnerabilities. In addition to the HPA axis, the hypothalamo-neurohypophyseal tract (HNT) is also activated in response to stress. In adults, stress activates this system resulting in secretion of oxytocin from neurons in the supraoptic (SON) and paraventricular (PVN) nuclei. However, it is currently unknown whether a similar or different response occurs in prepubertal animals. Given the influence of these hormones on a variety of emotional behaviors and physiological systems known to change as an animal transitions into adulthood, we investigated stress-induced HPA and HNT hormonal responses before and after stress, as well as the number and size of oxytocin-containing cells in the SON and PVN of prepubertal (30d) and adult (70d) male and female rats. Though we found the well-established protracted adrenocorticotropic hormone and corticosterone response in prepubertal males and females, only adult males and prepubertal females showed a significant stress-induced increase in plasma oxytocin levels. Moreover, though we found no pubertal changes in the number of oxytocin cells, we did find a pubertal-related increase in oxytocin somal size in both the SON and PVN of males and females. Taken together, these data indicate that neuroendocrine systems can show different patterns of stress reactivity before and after adolescent development and that these responses can be further modified by sex. Given the impact of these hormones on a variety of systems, it will be imperative to further explore these changes in hormonal stress reactivity and their role in adolescent health. PMID:26972154

  19. A detailed viscoelastic characterization of the P17 and adult rat brain.

    PubMed

    Elkin, Benjamin S; Ilankovan, Ashok I; Morrison, Barclay

    2011-11-01

    Brain is a morphologically and mechanically heterogeneous organ. Although rat brain is commonly used as an experimental neurophysiological model for various in vivo biomechanical studies, little is known about its regional viscoelastic properties. To address this issue, we have generated viscoelastic mechanical property data for specific anatomical regions of the P17 and adult rat brain. These ages are commonly used in rat experimental models. We measured mechanical properties of both white and gray matter regions in coronal slices with a custom-designed microindentation device performing stress-relaxation indentations to 10% effective strain. Shear moduli calculated for short (100?ms), intermediate (1?sec), and long (20?sec) time points, ranged from ?1?kPa for short term moduli to ?0.4?kPa for long term moduli. Both age and anatomic region were significant factors affecting the time-dependent shear modulus. White matter regions and regions of the cerebellum were much more compliant than those of the hippocampus, cortex, and thalamus. Linear viscoelastic models (Prony series, continuous phase lag, and a power law model) were fit to the time-dependent shear modulus data. All models fit the data equally with no significant differences between them (F-test; p>0.05). The F-test was also used to statistically determine that a Prony series with three time-dependent parameters accurately fit the data with no added benefit from additional terms. The age- and region-dependent rat brain viscoelastic properties presented here will help inform future biomechanical models of the rat brain with specific and accurate regional mechanical property data. PMID:21341982

  20. Effects of running wheel training on adult obese rats programmed by maternal prolactin inhibition.

    PubMed

    Boaventura, G; Casimiro-Lopes, G; Pazos-Moura, C C; Oliveira, E; Lisboa, P C; Moura, E G

    2013-10-01

    The inhibition of maternal prolactin production in late lactation leads to metabolic syndrome and hypothyroidism in adult offspring. Physical training is a therapeutic strategy that could prevent or reverse this condition. We evaluated the effects of a short-duration low-intensity running wheel training program on the metabolic and hormonal alterations in rats. Lactating Wistar rats were treated with bromocriptine (Bro, 1 mg twice a day) or saline on days 19, 20, and 21 of lactation, and the training of offspring began at 35 days of age. Offspring were divided into sedentary and trained controls (C-Sed and C-Ex) and sedentary and trained Bro-treated rats (Bro-Sed and Bro-Ex). Chronic exercise delayed the onset of weight gain in Bro-Ex offspring, and the food intake did not change during the experimental period. At 180 days, visceral fat mass was higher (+46%) in the Bro-Sed offspring than in C-Sed and Bro-Ex rats. As expected, running capacity was higher in trained animals. Most parameters observed in the Bro-Sed offspring were consistent with hypothyroidism and metabolic syndrome and were reversed in the Bro-Ex group. Chronic exercise did not influence the muscle glycogen in the C-Ex group; however, liver glycogen was higher (+30%) in C-Ex group and was unchanged in both Bro offspring groups. Bro-Ex animals had higher plasma lactate dehydrogenase levels, indicating skeletal muscle damage and intolerance of the training program. Low-intensity chronic training is able to normalize many clinical aspects in Bro animals; however, these animals might have had a lower threshold for exercise adaptation than the control rats. PMID:23863192

  1. Developmental vitamin D (DVD) deficiency in the rat alters adult behaviour independently of HPA function.

    PubMed

    Eyles, Darryl W; Rogers, Fiona; Buller, Kathryn; McGrath, John J; Ko, Pauline; French, Kathryn; Burne, Thomas H J

    2006-09-01

    Developmental vitamin D deficiency (DVD) has been shown to alter the orderly pattern of brain development. Even though the period of vitamin D deficiency is restricted to gestation this is sufficient to induce behavioural abnormalities in the adult offspring consistent with those seen in many animal models of schizophrenia. Given that some of these behavioural alterations could also be an indirect result of either impaired maternal hypothalamic pituitary axis (HPA) function (which in turn could influence maternal care) or the result of a permanent alteration in HPA function in the adult offspring we have examined HPA status in both maternal animals and adult offspring. In this study we have established that HPA function is normal in the maternally vitamin D deficient rat. We replicate the behavioural phenotype of hyperlocomotion whilst establishing that HPA function is also unchanged in the adult male offspring. We conclude that the behavioural alterations induced by DVD deficiency are due to some adverse event in brain development rather than via an alteration in stress response. PMID:16890375

  2. Differential stress reactivity in intact and ovariectomized prepubertal and adult female rats.

    PubMed

    Romeo, Russell D; Lee, Susan J; McEwen, Bruce S

    2004-01-01

    The pubertal development of the hypothalamic-pituitary-adrenal (HPA) axis has received relatively little experimental attention. As puberty is marked by an increase in the susceptibility to various psychiatric disorders that may be related to HPA dysfunction, it is imperative to elucidate the pubertal development of this neuroendocrine axis. To date, the limited research in this area has been conducted primarily on males. Presently, we investigated stress responsiveness, as measured by both stress hormones (e.g., corticotropin (ACTH) and corticosterone) and gonadal steroids, in intact and ovariectomized prepubertal and adult female rats before and after a 30-min session of restraint stress. We report here that intact prepubertal females exhibit an extended corticosterone stress response (30-45 min longer) compared to intact adults. Moreover, ovariectomized prepubertal females continue to exhibit a prolonged stress-induced corticosterone and progesterone response compared to ovariectomized adults, indicating these protracted responses prior to puberty are independent of ovarian hormones. ACTH levels were not significantly different between intact and ovariectomized prepubertal and adult animals at all the post-stress time points measured, suggesting that the prolonged corticosterone response in prepubertal females is due to an enhanced sensitivity to ACTH at the level of the adrenal cortex. Taken together, these data indicate that stress reactivity changes dramatically during puberty in females. Furthermore, these data demonstrate additional development of the HPA axis during pubertal maturation, resulting in a more quickly terminated stress response in adulthood.

  3. The social behavior of male rats administered an adult-onset calorie restriction regimen.

    PubMed

    Govic, Antonina; Levay, Elizabeth A; Kent, Stephen; Paolini, Antonio G

    2009-03-23

    The behavioral outcomes of a calorie restricted diet are often neglected in favour of a more physiological examination of the consequences of calorie restriction (CR). This is especially the case with social behavior. A few findings within the maternal CR literature suggest that adult male social behavior is altered by this regimen. Despite the paucity of findings within the maternal CR literature, a systematic investigation of the behavioral phenotype of males administered an adult-onset CR is completely lacking and was the focus of the current study. Adult male hooded Wistar rats were administered a three week CR, with one group receiving a 25% CR and another group receiving a 50% CR before male-to-male social behavior was examined and compared with ad libitium fed males. Various behavioral elements were modulated by CR, both the CR25% and 50% group initiated contact sooner and engaged in greater social activity compared to the ad libitum fed controls. The CR25% group also demonstrated less non-social (self-grooming) behavior and a greater frequency of walkovers compared to all groups, indicating a propensity towards dominance. The CR50% group demonstrated greater environmental assessment/exploration, as measured by the frequency of rearing. As with the maternal CR literature, an adult-onset chronic CR induces a more socially active behavioral phenotype and reduces interest in non-social behavior in the moderately CR group. Taken together, the social behavioral phenotype can be modulated by a CR initiated and maintained during adulthood.

  4. Impulsive choice and anxiety-like behavior in adult rats exposed to chronic intermittent ethanol during adolescence and adulthood.

    PubMed

    Mejia-Toiber, Jana; Boutros, Nathalie; Markou, Athina; Semenova, Svetlana

    2014-06-01

    Binge drinking during adolescence and adulthood may have differential long-term effects on the brain. We investigated the long-term effects of chronic intermittent ethanol (CIE) exposure during adolescence and adulthood on impulsivity and anxiety-like behavior. Adolescent (adolescent-exposed) and adult (adult-exposed) rats were exposed to CIE/water on postnatal days (PND) 28-53 and PND146-171, respectively, and a 4-day ethanol/water binge on PND181-184 and PND271-274, respectively. During withdrawal from CIE and 4-day binge exposures, anxiety-like behavior and arousal were measured in the light-potentiated startle (LPS) and acoustic startle (ASR) procedures, respectively. Impulsive choice was evaluated in the delay discounting task (DDT) at baseline and after ethanol challenges. Independent of age, ASR and LPS were decreased during withdrawal from CIE exposure. In contrast, LPS was increased in adult-exposed, but not adolescent-exposed, rats during withdrawal from the 4-day ethanol binge. CIE exposure had no effect on preference for the large delayed reward at baseline, independent of age. During DDT acquisition, CIE-exposed, compared with water-exposed rats, omitted more responses, independent of age, suggesting the CIE-induced disruption of cognitive processes. Ethanol challenges decreased preference for the large reward in younger adolescent-exposed rats but had no effect in older adult-exposed rats, independent of previous CIE/water exposure. Taken together, the present studies demonstrate that CIE withdrawal-induced decreases in anxiety and arousal were not age-specific. CIE exposure had no long-term effects on baseline impulsive choice. Subsequent ethanol exposure produced age-dependent effects on impulsivity (increased impulsivity in younger adolescent-exposed rats) and anxiety-like behavior (increased anxiety-like behavior in older adult-exposed rats).

  5. Chronically reinforced, operant olfactory conditioning increases the number of newborn GABAergic olfactory periglomerular neurons in the adult rat.

    PubMed

    Tapia-Rodríguez, Miguel; Esquivelzeta-Rabell, José F; Gutiérrez-Ospina, Gabriel

    2012-12-01

    The mammalian brain preserves the ability to replace olfactory periglomerular cells (PGC) throughout life. Even though we have detailed a great deal the mechanisms underlying stem and amplifying cells maintenance and proliferation, as well as those modulating migration and differentiation, our knowledge on PGC phenotypic plasticity is at best fragmented and controversial. Here we explored whether chronically reinforced olfactory conditioning influences the phenotype of newborn PGC. Accordingly, olfactory conditioned rats showed increased numbers of GAD 65/67 positive PGC. Because such phenotypic change was not accompanied neither by increments in the total number of PGC, or periglomerular cell nuclei labeled with bromodeoxyuridine, nor by reductions in the number of tyrosine hydroxylase (TH), calbindin (CB) or calretinin (CR) immunoreactive PGC, we speculate that increments in the number of GABAergic PGC occur at the expense of other PGC phenotypes. In any event, these results support that adult newborn PGC phenotype may be subjected to phenotypic plasticity influenced by sensory stimulation.

  6. Influence of acrylamide on the gastric mucosa of adult albino rats and the possible protective role of rosemary.

    PubMed

    El-Mehi, Abeer E; El-Sherif, Neveen M

    2015-06-01

    Acrylamide is a common chemical found in heated starchy foods especially potato products. We investigated, for the first time, the effect of acrylamide, alone or with rosemary, on the structure of gastric mucosa of adult male albino rats. Stomach sections were examined using light and scanning electron microscopy. Quantitative immmunohistochemical assessments of the expression of caspase-3, inducible NO synthase (iNOS) and epidermal growth factor receptor (EPGR) were performed. Our results showed that acrylamide produced mucosal erosions and depletion of the protective surface mucus together with widespread inflammatory infiltration. In addition, there was significantly increased expression of caspase-3 and iNOS and weak expression of EPGR. Rosemary exerted a protective effect against acrylamide-induced gastric toxicity via reducing oxidative stress, apoptosis and inflammation as well as accelerating the healing process. The results of this work add to the known toxic effects of acrylamide and provide a new insight into the possible use of rosemary to ameliorate these effects.

  7. Differential effects of insulin and dietary amino acids on muscle protein synthesis in adult and old rats

    PubMed Central

    Prod'homme, Magali; Balage, Michèle; Debras, Elisabeth; Farges, Marie-Chantal; Kimball, Scott; Jefferson, Leonard; Grizard, Jean

    2005-01-01

    The potential roles of insulin and dietary amino acids in the regulation of skeletal muscle protein synthesis were examined in adult and old rats. Animals were fed over 1 h with either a 25% or a 0% amino acid/protein meal. In each nutritional condition, postprandial insulin secretion was either maintained or blocked with diazoxide injections. Protein synthesis in gastrocnemius and soleus muscles was assessed in vivo using the flooding dose method. Insulin suppression decreased protein synthesis in both muscles irrespective of the nutritional condition and age of the rats. Moreover, reduced insulinaemia was associated with 4E-BP1 dephosphorylation, enhanced assembly of the 4E-BP1−eIF4E inactive complex and hypophosphorylation of eIF4E, p70S6k and protein kinase B, key intermediates in the regulation of translation initiation and protein synthesis. Old rats did not differ from adult rats. The lack of amino acids in the meal of insulin-suppressed rats did not result in any additional decrease in protein synthesis. In the presence of insulin secretion, dietary amino acid suppression significantly decreased gastrocnemius protein synthesis in adult but not in old rats. Amino acid suppression was associated with reduced phosphorylation of 4E-BP1 and p70S6k in adults. Along with protein synthesis, only the inhibition of p70S6k phosphorylation was abolished in old rats. We concluded that insulin is required for the regulation of muscle protein synthesis irrespective of age and that the effect of dietary amino acids is blunted in old rats. PMID:15513948

  8. Inhibition by dietary D-psicose of body fat accumulation in adult rats fed a high-sucrose diet.

    PubMed

    Ochiai, Masaru; Nakanishi, Yosuke; Yamada, Takako; Iida, Tetsuo; Matsuo, Tatsuhiro

    2013-01-01

    We investigated the anti-obesity effects of dietary D-psicose on adult rats fed a high-sucrose diet. Wistar rats (16 weeks old) that had previously been fed a high-sucrose diet (HSD) were fed HSD or a high-starch diet (HTD) with or without 5% D-psicose for 8 weeks. The food efficiency, carcass fat percentage, abdominal fat accumulation, and body weight gain were all significantly suppressed by dietary D-psicose.

  9. Sexual odor discrimination and physiological profiles in adult male rats after a neonatal, short term, reversible nasal obstruction.

    PubMed

    Thornton, S N; Padzys, G S; Trabalon, M

    2014-05-01

    The present study was designed to examine behavioral responses (interpreted as preferences) to olfactory cues (nest bedding odor and odors of estrous and anestrus females) in adult male rats after they had a short term reversible, bilateral, nasal obstruction (RbNO) as developing rat pups. These results were compared to behavior of control (untreated) and sham operated male littermates. Behavioral tests and physiological parameters were analyzed 90 days after recovery of nasal breathing. Experiments investigated the time spent in arms or the center of a maze of male rats in response to odors from the nest bedding or from adult females. There were no differences in responses between untreated, sham and RbNO adult male rats to fresh and nest bedding odors. RbNO males spent more time in the center of the maze when given a choice of estrus or anestrus female odors, or bedding odors from untreated or sham operated female rats. In contrast untreated and sham male rats preferred the odors of estrous females and of untreated or sham females. Plasma corticosterone levels in the males increased during the behavioral tests. Plasma testosterone levels were significantly lower in RbNO males compared to untreated males and did not increase during the behavioral tests compared to sham operated males. Males from all groups had similar preferences for the odor of bedding from adult RbNO females. Plasma levels of cholesterol and triglycerides were increased in RbNO adults. In conclusion, short term nasal obstruction in males while juvenile has long term consequences on hormones and behavioral preferences, thus potential partner selection when adult.

  10. Perinatal protein deprivation facilitates accumbal ERK phosphorylation in cocaine-sensitized adult rats.

    PubMed

    Velazquez, E E; Valdomero, A; Maldonado, N M; Orsingher, O A; Cuadra, G R

    2013-03-15

    In previous studies we described that perinatal protein deprivation facilitates the development and expression of behavioral sensitization to cocaine. In this research, we explored whether the increased reactivity observed in deprived (D) versus control (C) rats is also evident during drug-free withdrawal periods. Considering that activation of the extracellular signal-regulated protein kinase (ERK) is suggested to be involved in cocaine-induced behavioral sensitization, we study the effects of perinatal protein deprivation on phosphorylated ERK2 (pERK2) protein levels in the NAc (core and shell) during different drug-free withdrawal periods. To induce behavioral sensitization, C- and D-rats received a daily injection of cocaine (5-10 mg/kg, i.p.) for 7 days and locomotor activity was performed on days 1 and 7. Cocaine-sensitized animals were left drug-free and pERK2 was assessed on withdrawal days (WD) 1, 4, 7 and 21. In the NAc core, cocaine induced ERK signaling pathway activation in a dose-dependent manner, and only D-rats showed a significant increase in pERK2 protein levels with the lowest dose of cocaine (5 mg/kg). Moreover, sensitized C-rats with 10 mg/kg showed an increase in pERK2 levels from WD7 while D-rats showed this activation on WD4, which remained increased on WD7 and 21. In contrast, in the NAc shell, only sensitized D-rats with cocaine 10 mg/kg showed ERK2 activation on WD21. These results suggest that perinatal protein deprivation facilitates the molecular processes involved in neuronal plasticity occurring during withdrawal.

  11. Effects of age, but not sex, on elevated startle during withdrawal from acute morphine in adolescent and adult rats.

    PubMed

    Radke, Anna K; Gewirtz, Jonathan C; Carroll, Marilyn E

    2015-08-01

    Investigations into animal models of drug withdrawal have largely found that emotional signs of withdrawal (e.g. anxiety, anhedonia, and aversion) in adolescents are experienced earlier and less severely than in their adult counterparts. The majority of these reports have examined withdrawal from ethanol or nicotine. To expand our knowledge about the emotional withdrawal state in adolescent rats, we used potentiation of the acoustic startle reflex after an acute dose of morphine (10 mg/kg, subcutaneously) as a measure of opiate withdrawal. Startle was measured at four time points after morphine injection (2, 3, 4, and 5 h) in 28-day-old and 90-day-old male and female rats. The results of this experiment revealed that peak potentiation of the startle reflex occurred at 3 h in the adolescent rats and at 5 h in the adult rats, and that the magnitude of withdrawal was larger in the adults. No sex differences were observed. Overall, these results affirm that, similar to withdrawal from ethanol and nicotine, opiate withdrawal signs are less severe in adolescent than in adult rats.

  12. Effects of age, but not sex, on elevated startle during withdrawal from acute morphine in adolescent and adult rats

    PubMed Central

    Radke, Anna K.; Gewirtz, Jonathan C.; Carroll, Marilyn E.

    2015-01-01

    Investigations into animal models of drug withdrawal have largely found that emotional signs of withdrawal (e.g., anxiety, anhedonia, and aversion) in adolescents are experienced earlier and less severely than in their adult counterparts. The majority of these reports have examined withdrawal from ethanol or nicotine. In order to expand our knowledge about the emotional withdrawal state in adolescent rats, we used potentiation of the acoustic startle reflex after an acute dose of morphine (10 mg/kg, s.c.) as a measure of opioid withdrawal. Startle was measured at four time points after morphine injection (2, 3, 4, and 5 h) in 28 and 90 day old male and female rats. The results of this experiment revealed that peak potentiation of the startle reflex occurred at 3 h in the adolescent rats and at 5 h in the adult rats, and that the magnitude of withdrawal was larger in the adults. No sex differences were observed. Overall, these results affirm that, similar to withdrawal from ethanol and nicotine, opiate withdrawal signs are less severe in adolescent than in adult rats. PMID:26154436

  13. Prenatal restraint stress decreases the expression of alpha-7 nicotinic receptor in the brain of adult rat offspring.

    PubMed

    Baier, Carlos J; Pallarés, María E; Adrover, Ezequiela; Monteleone, Melisa C; Brocco, Marcela A; Barrantes, Francisco J; Antonelli, Marta C

    2015-01-01

    Prenatal stress (PS) strongly impacts fetal brain development and function in adulthood. In normal aging and Alzheimer's disease, there is hypothalamic-pituitary-adrenal axis dysfunction and loss of cholinergic neurons and neuronal nicotinic acetylcholine receptors (nAChRs). This study investigated whether prenatal restraint stress affects nAChR expression in the brain of adult offspring. For PS, pregnant dams were placed in a plastic restrainer for 45 min, three times daily during the last week of pregnancy; controls were undisturbed. Male offspring were analyzed at postnatal day (PND) 60 (n = 4 rats per group). Western blot (WB) and fluorescence microscopy showed that PS decreased α7-AChR subunit expression (∼50%) in the frontal cortex in the adult offspring. PS decreased significantly the number of α7-AChR-expressing cells in the medial prefrontal cortex (by ∼25%) and in the sensory-motor cortex (by ∼20%) without affecting the total cell number in those areas. No alterations were found in the hippocampus by quantitative polymerase chain reaction (qPCR), or WB analysis, but a detailed fluorescence microscopy analysis showed that PS affected α7-AChR mainly in the CA3 and dentate gyrus subfields: PS decreased α7-AChR subunit expression by ∼25 and ∼30%, respectively. Importantly, PS decreased the number of α7-AChR-expressing cells and the total cell number (by ∼15 and 20%, respectively) in the dentate gyrus. PS differently affected α4-AChR: PS impaired its mRNA expression in the frontal cortex (by ∼50%), without affecting protein levels. These results demonstrate that disturbances during gestation produce long-term alterations in the expression pattern of α7-AChR in rat brain.

  14. Subacute toxicity assessment of diflubenzuron, an insect growth regulator, in adult male rats.

    PubMed

    de Barros, Aline Lima; Cavalheiro, Gabriela Finoto; de Souza, Alexsandra Vila Maior; Traesel, Giseli Karenina; Anselmo-Franci, Janete A; Kassuya, Cândida Aparecida Leite; Arena, Arielle Cristina

    2016-04-01

    Diflubenzuron (DFB), an insecticide and acaricide insect growth regulator, can be used in agriculture against insect predators and in public health programs, to control insects and vectors, mainly Aedes aegypti larvae. Due to the lack of toxicological assessments of this compound, the objective of the present study was to evaluate the toxicological effects of subacute exposure to the DFB insecticide in adult male rats. Adult male rats were exposed (gavage) to 0, 2, 4, or 8 mg/kg of DFB for 28 days. No clinical signs of toxicity were observed in the DFB-treated animals of the experimental groups. However, there was an increase in serum levels of alanine aminotransferase in the group that received 8 mg/kg/DFB/day and urea at doses of 4 and 8 mg/kg/DFB/day, without altering other biochemical or hematological parameters. The subacute exposure to the lowest dose of DFB caused significant decrease in testis weight, daily sperm production, and in number of sperm in the epididymis in relation to the control group. However, no alterations were observed in the sperm morphology, testicular, epididymis, liver and kidney histology, or testosterone levels. These findings unveiled the hazardous effects of DFB on male reproduction after the subacute exposure and special attention should be addressed to the effects of low doses of this pesticide.

  15. Impact of neonatal anoxia on adult rat hippocampal volume, neurogenesis and behavior.

    PubMed

    Takada, Silvia Honda; Motta-Teixeira, Lívia Clemente; Machado-Nils, Aline Vilar; Lee, Vitor Yonamine; Sampaio, Carlos Alberto; Polli, Roberson Saraiva; Malheiros, Jackeline Moraes; Takase, Luiz Fernando; Kihara, Alexandre Hiroaki; Covolan, Luciene; Xavier, Gilberto Fernando; Nogueira, Maria Inês

    2016-01-01

    Neonates that suffer oxygen deprivation during birth can have long lasting cognitive deficits, such as memory and learning impairments. Hippocampus, one of the main structures that participate in memory and learning processes, is a plastic and dynamic structure that conserves during life span the property of generating new cells which can become neurons, the so-called neurogenesis. The present study investigated whether a model of rat neonatal anoxia, that causes only respiratory distress, is able to alter the hippocampal volume, the neurogenesis rate and has functional implications in adult life. MRI analysis revealed significant hippocampal volume decrease in adult rats who had experienced neonatal anoxia compared to control animals for rostral, caudal and total hippocampus. In addition, these animals also had 55.7% decrease of double-labelled cells to BrdU and NeuN, reflecting a decrease in neurogenesis rate. Finally, behavioral analysis indicated that neonatal anoxia resulted in disruption of spatial working memory, similar to human condition, accompanied by an anxiogenic effect. The observed behavioral alterations caused by oxygen deprivation at birth might represent an outcome of the decreased hippocampal neurogenesis and volume, evidenced by immunohistochemistry and MRI analysis. Therefore, based on current findings we propose this model as suitable to explore new therapeutic approaches.

  16. Environmental enrichment protects the retina from early diabetic damage in adult rats.

    PubMed

    Dorfman, Damián; Aranda, Marcos L; González Fleitas, María Florencia; Chianelli, Mónica S; Fernandez, Diego C; Sande, Pablo H; Rosenstein, Ruth E

    2014-01-01

    Diabetic retinopathy is a leading cause of reduced visual acuity and acquired blindness. Available treatments are not completely effective. We analyzed the effect of environmental enrichment on retinal damage induced by experimental diabetes in adult Wistar rats. Diabetes was induced by an intraperitoneal injection of streptozotocin. Three days after vehicle or streptozotocin injection, animals were housed in enriched environment or remained in a standard environment. Retinal function (electroretinogram, and oscillatory potentials), retinal morphology, blood-retinal barrier integrity, synaptophysin, astrocyte and Müller cell glial fibrillary acidic protein, vascular endothelial growth factor, tumor necrosis factor-α, and brain-derived neurotrophic factor levels, as well as lipid peroxidation were assessed in retina from diabetic animals housed in standard or enriched environment. Environmental enrichment preserved scotopic electroretinogram a-wave, b-wave and oscillatory potential amplitude, avoided albumin-Evan's blue leakage, prevented the decrease in retinal synaptophysin and astrocyte glial fibrillary acidic protein levels, the increase in Müller cell glial fibrillary acidic protein, vascular endothelial growth factor and tumor necrosis factor-α levels, as well as oxidative stress induced by diabetes. In addition, enriched environment prevented the decrease in retinal brain-derived neurotrophic factor levels induced by experimental diabetes. When environmental enrichment started 7 weeks after diabetes onset, retinal function was significantly preserved. These results indicate that enriched environment could attenuate the early diabetic damage in the retina from adult rats.

  17. Altered adult hippocampal neuronal maturation in a rat model of fetal alcohol syndrome.

    PubMed

    Gil-Mohapel, Joana; Boehme, Fanny; Patten, Anna; Cox, Adrian; Kainer, Leah; Giles, Erica; Brocardo, Patricia S; Christie, Brian R

    2011-04-12

    Exposure to ethanol during pregnancy can be devastating to the developing nervous system, leading to significant central nervous system dysfunction. The hippocampus, one of the two brain regions where neurogenesis persists into adulthood, is particularly sensitive to the teratogenic effects of ethanol. In the present study, we tested a rat model of fetal alcohol syndrome (FAS) with ethanol administered via gavage throughout all three trimester equivalents. Subsequently, we assessed cell proliferation, as well as neuronal survival, and differentiation in the dentate gyrus of the hippocampus of adolescent (35 days old), young adult (60 days old) and adult (90 days old) Sprague-Dawley rats. Using both extrinsic (bromodeoxyuridine) and intrinsic (Ki-67) markers, we observed no significant alterations in cell proliferation and survival in ethanol-exposed animals when compared with their pair-fed and ad libitum controls. However, we detected a significant increase in the number of new immature neurons in animals that were exposed to ethanol throughout all three trimester equivalents. This result might reflect a compensatory mechanism to counteract the deleterious effects of prenatal ethanol exposure or an ethanol-induced arrest of the neurogenic process at the early neuronal maturation stages. Taken together these results indicate that exposure to ethanol during the period of brain development causes a long-lasting dysregulation of the neurogenic process, a mechanism that might contribute, at least in part, to the hippocampal deficits that have been reported in rodent models of FAS.

  18. Environmental Enrichment Protects the Retina from Early Diabetic Damage in Adult Rats

    PubMed Central

    Dorfman, Damián; Aranda, Marcos L.; González Fleitas, María Florencia; Chianelli, Mónica S.; Fernandez, Diego C.; Sande, Pablo H.; Rosenstein, Ruth E.

    2014-01-01

    Diabetic retinopathy is a leading cause of reduced visual acuity and acquired blindness. Available treatments are not completely effective. We analyzed the effect of environmental enrichment on retinal damage induced by experimental diabetes in adult Wistar rats. Diabetes was induced by an intraperitoneal injection of streptozotocin. Three days after vehicle or streptozotocin injection, animals were housed in enriched environment or remained in a standard environment. Retinal function (electroretinogram, and oscillatory potentials), retinal morphology, blood-retinal barrier integrity, synaptophysin, astrocyte and Müller cell glial fibrillary acidic protein, vascular endothelial growth factor, tumor necrosis factor-α, and brain-derived neurotrophic factor levels, as well as lipid peroxidation were assessed in retina from diabetic animals housed in standard or enriched environment. Environmental enrichment preserved scotopic electroretinogram a-wave, b-wave and oscillatory potential amplitude, avoided albumin-Evan's blue leakage, prevented the decrease in retinal synaptophysin and astrocyte glial fibrillary acidic protein levels, the increase in Müller cell glial fibrillary acidic protein, vascular endothelial growth factor and tumor necrosis factor-α levels, as well as oxidative stress induced by diabetes. In addition, enriched environment prevented the decrease in retinal brain-derived neurotrophic factor levels induced by experimental diabetes. When environmental enrichment started 7 weeks after diabetes onset, retinal function was significantly preserved. These results indicate that enriched environment could attenuate the early diabetic damage in the retina from adult rats. PMID:25004165

  19. Effects of Rolipram on Adult Rat Oligodendrocytes and Functional Recovery after Contusive Cervical Spinal Cord Injury

    PubMed Central

    Beaumont, Eric; Whitaker, Christopher M.; Burke, Darlene A.; Hetman, Michal; Onifer, Stephen M.

    2009-01-01

    Traumatic human spinal cord injury causes devastating and long-term hardships. These are due to the irreparable primary mechanical injury and secondary injury cascade. In particular, oligodendrocyte cell death, white matter axon damage, spared axon demyelination, and the ensuing dysfunction in action potential conduction lead to the initial deficits and impair functional recovery. For these reasons, and that oligodendrocyte and axon survival may be related, various neuroprotective strategies after SCI are being investigated. We previously demonstrated that oligodendrocytes in the