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Pentobarbital intoxication in the pregnant rat.  


Pregnant rats were treated intraperitoneally with low doses of pentobarbital (5, 15 or 25 mg/kg) on days 9 through 12 of gestation. There was no significant differences in fetal weight, length, or placental weight. Other than minor ossification delays, there were no external, skeletal or visceral abnormalities and no treatment-related variation in fetal mortality. Microscopic examination of various maternal and fetal tissues revealed no major deleterious effects of short-term pentobarbital intoxication. PMID:663399

Kennedy, L A; Persaud, T V



Gastric inhibitory polypeptide and gastric acid secretion in pregnant rats.  


The effects of pregnancy on the basal and pentagastrin-stimulated gastric acid secretion and the level of plasma gastric inhibitory polypeptide (GIP) in rats were studied on pentobarbital-anaesthetized non-pregnant rats and rats in the 1st, 2nd, or 3rd week of gestation. Acid output was determined by titration of the gastric perfusate. Basal secretion was collected for 45 min before a 30 min infusion of pentagastrin (8 micrograms/ml/300 g body weight). Concentration of plasma GIP was measured by a radioimmunoassay (RIA). The immunoreactivity of GIP-like substance in the extract of the rat placenta collected from the rat at day 21 of gestation was examined by RIA. The biological activity of GIP-like substance in the rat placenta extract was tested by the reduction of pentagastrin-stimulated gastric acid secretion in male rats. The basal level of gastric secretion was higher in late pregnancy as compared with the non-pregnant rats. Pentagastrin induced a greater increase of gastric acid secretion in early but not late pregnant rats as compared with the non-pregnant animals. The basal and post-pentagastrin level of plasma GIP was higher in rats in late pregnancy. Both immunoreactivity and biological activity of GIP exist in the rat placenta extract. These results suggest that the normalization of gastric acid secretion in late pregnant rats is at least in part due to the production of GIP-like substance from placenta. PMID:7716131

Chen, T S; Yeh, G H; Pu, H F; Doong, M L; Lu, C C; Liu, S R; Young, T K; Ho, L T; Chang, F Y; Wang, P S



Megaloblastic hematopoiesis in a 20 year old pregnant female  

PubMed Central

Summary Background: Nitrous oxide can cause disordered blood cell proliferation and lead to pancytopenia and altered immune function. Case Report: A young pregnant female patient presented after binge nitrous oxide abuse with altered mental status and abnormal vital signs. From her initial assessment she was noted to have pancytopenia and was found to have megaloblastic, hyper-cellular changes in a subsequent bone marrow biopsy. This presentation was determined to be secondary to toxic effects after heavy use of nitrous oxide. Conclusions: Nitrous oxide exposure, including use as an inhalant, over 12 hours can lead to bone marrow abnormalities such as megaloblastic hematopoiesis. PMID:23569553

Trivette, Evan T.; Hoedebecke, Kyle; Berry-Cabán, Cristóbal S.; Jacobs, Brandy R.



Differential effect of neocuproine, a copper(I) chelator, on contractile activity in isolated ovariectomized non-pregnant rat, pregnant rat and pregnant human uterus.  


The study was conducted to examine effects of a selective copper(I) chelator, neocuproine on the spontaneous or oxytocin-induced contractions in isolated ovariectomized non-pregnant rat, pregnant rat and pregnant human uterus. Uterus activity was evaluated in tissues obtained from bilaterally ovariectomized non-pregnant rats on the 21st day of the operation (n = 24), pregnant rats on the 19-21st day of gestation (n = 24) and women undergoing caesarean section at 38-42 weeks of pregnancy (n = 15). Neocuproine (100 microM) significantly suppressed the amplitude and frequency of the spontaneous contractions in the ovariectomized non-pregnant rat uterus while this agent facilitated the frequency of the spontaneous or oxytocin-induced contractions in the pregnant rat and human uterus without altering the amplitude of these contractions. At high concentration of 200 microM, neocuproine could enhance the amplitude of the contractions in the pregnant uterus. These effects were blocked by a purinergic receptor antagonist, suramin (100 microM) and did not occur following the administration of neocuproine-copper(I) complex or copper(II) chelator cuprizone. alpha, beta-methylene ATP increased the amplitude and frequency of contractions in the pregnant uterus, but not affected the contractions in the ovariectomized non-pregnant rat uterus, and neocuproine potentiated this facilitation effect. However, the suppressive effect of neocuproine on the ovariectomized non-pregnant rat uterus increased in the presence of alpha,beta-methylene ATP. Beta-adrenoceptor blocker, propranolol or nitric oxide synthase inhibitor, L-nitroarginine did not affect the responses to neocuproine. These findings suggest that neocuproine can affect the uterus contractile activity by modulation purinergic excitatory responses and that copper(I)-sensitive mechanisms may play a role in this effect. PMID:19248249

Kumcu, Eda Karabal; Büyüknacar, Hacer Sinem Göktürk; Göçmen, Cemil; Evrüke, Ismail Cüneyt; Onder, Serpil




EPA Science Inventory

The purpose of this study was to evaluate the teratogenic potential of Imidan in Wistar rats. Accordingly, groups of pregnant Wistar rats received Imidan by either a single or multiple dose protocol and their fetuses were examined for gross, soft tissue, and skeletal defects. In ...


Carbamazepine pharmacokinetics in young, adult and pregnant rats. Relation to pharmacological effects.  


Adult, male, female and pregnant rats were treated with single and repeated doses of carbamazepine (CBZ). The time course of the drug concentrations in plasma and tissues was followed. In all cases, data on plasma levels were subjected to pharmacokinetic analyses. Attempts were made to relate pharmacokinetic properties of carbamazepine to its effect on pentobarbital sleeping time and on protection against electroshock, after acute and repeated administration: --it was found that male rats eliminate carbamazepine faster than females: the total body clearance (TBC) was 16 ml/min/kg and 9.4 ml/min/kg, respectively. Two dose levels (25 and 50 mg/kg) had the same pharmacokinetic properties in young rats. Pregnant rats clear CBZ to a lesser extent than controls. --CBZ was found to accelerate its own elimination after repeated administration in both adult and young rats as revealed by the shortening of its half-life and an increase of 50% in clearance. Moreover, the protection against electroshock was significantly reduced after repeated administration, compared with a single-dose administration. Repeated administration of CBZ in rats shortens pentobarbital sleeping time and decreases the pentobarbital brain level significantly. PMID:952573

Farghali-Hassan; Assael, B M; Bossi, L; Garattini, S; Gerna, M; Gomeni, R; Morselli, P L



Distribution of ochratoxin A in the pregnant rat  

E-print Network

Najor Subject: Laboratory Anima1 Pedi ', ne DISTRIBUTION OF OCHRATOXIN A IN THE PREGNANT RAT A Thesis by MICHAEL BRENT BALLINGER Approved as to style and content by: G. N. , Joiner (Co-Chairman of Committee) n s (Co-Chairman of Committee) . N...

Ballinger, Michael Brent



Dietary calcium and phosphorus manipulations in thyroparathyroidectomized pregnant rats  

E-print Network

Dietary calcium and phosphorus manipulations in thyroparathyroidectomized pregnant rats and fetal vitamin D3 meta- bolite injection to the mothers when their plasma calcium is low or slightly elevated. To determine the putative role of calcium in these experiments, we elevated TPTX maternal plasma calcium

Paris-Sud XI, Université de


Bioavailability of vitamin B-6 in pregnant rats.  


The cause for reduced plasma pyridoxal phosphate (PLP) concentration during pregnancy is not well understood. In this study, nonpregnant (control) and pregnant rats were gavaged with [3H]pyridoxine for assessment of the intestinal absorption, tissue distribution, metabolic utilization and urinary excretion of the vitamin. In addition, plasma PLP and pyridoxal levels and erythrocyte aspartate aminotransferase (EAST) activity were measured. There was 50% lower plasma PLP concentration and 50% greater EAST activity in the pregnant rats and no difference in the stimulation of EAST with exogenous PLP. There was no difference in the intestinal absorption, hepatic uptake and retention or urinary excretion of the radioisotope. Less than 3% of the oral dose was detected in fetal/uterine tissue of the pregnant rats. Results of this study indicate that reduced plasma PLP concentration during pregnancy is not a result of diminished total vitamin B-6 body pools or fetal sequestration of vitamin B-6. Low plasma PLP during pregnancy may be a result of altered distribution of PLP between the plasma and erythrocytes. PMID:1512639

Wang, J W; Trumbo, P R



The Adverse Effects of Oral 2-Mercaptobenzimidazole on Pregnant Rats and Their Fetuses  

Microsoft Academic Search

The Adverse Effects of Oral 2-Mercaptobenzimidazole on Pregnant Rats and Their Fetuses, Yamano, T., Noda, T., Shimizu, M., and Morita, S. (1995). Fundam. Appl. Toxicol. 25, 218-223.The effects of oral 2-mercaptobenzimidazole (2-MBI)on pregnant Wistar rats were examined. In a preliminary dose-finding study, pregnant rats treated with 2-MBI over Days 7-17 of gestation showed reduction in maternal thymus weights with compound-related

Tetsuo Yamano; Tsutomu Noda; Mitsuru Shimizu; Shigeru Morita



Use of urinary renal biomarkers to evaluate the nephrotoxic effects of melamine or cyanuric acid in non-pregnant and pregnant rats.  


Although traditional assessments of renal damage detect loss of kidney function, urinary renal biomarkers are proposed to indicate early changes in renal integrity. The recent adulteration of infant formula and other milk-based foods with melamine revealed a link between melamine ingestion and nephropathy. Thus, the effects of melamine and related analogs (e.g., cyanuric acid) should be assessed in other potentially sensitive groups. We evaluated whether urinary Kim-1, clusterin, and osteopontin could detect the effects of high doses of melamine or cyanuric acid in pregnant and non-pregnant female rats gavaged with 1000?mg/kg bw/day for 10 days. We demonstrate that these biomarkers can differentiate the severity of effects induced by melamine or cyanuric acid. All melamine-treated animals experienced adverse effects; however, pregnant rats were most sensitive as indicated by increased SCr, BUN, and kidney weights, decreased body weight, and presence of renal crystals. These effects coincided with elevated urinary biomarker levels as early as day 2 of exposure. One cyanuric acid-treated rat displayed effects similar to melamine, including increased urinary biomarker levels. This work illustrates that these biomarkers can detect early effects of melamine or cyanuric acid crystal-induced nephropathy and further supports the use of urinary protein immunoassays as a powerful, non-invasive method to assess nephrotoxicity. PMID:25455896

Bandele, O J; Stine, C B; Ferguson, M; Black, T; Olejnik, N; Keltner, Z; Evans, E R; Crosby, T C; Reimschuessel, R; Sprando, R L



Lectin histochemistry of pregnant rat uterine tissues.  


Glycoconjugate residues were examined in the rat uterus at days 10, 12 and 15 of pregnancy using 17 biotinylated lectins with specificities for a variety of carbohydrate moieties. A wide variety of glycoconjugate residues were detected in the cytoplasm of some antimesometrial and mesometrial decidual cells with lectins from Canavalia ensiformis (Con A), Lens culinaris (LcH) culinaris (LcH), Pisum sativum (PSA), Griffonia simplicifolia II (GS-II), Triticum vulgaris (WGA), Griffonia simplicifolia I (GS-I), Maclura pomifera (MPA) and Phaseolus vulgaris (PHA-E and PHA-L). Reactivity with some of these lectins was also pericellular and the glycoconjugate residues detected may be related to extracelluar matrix produced by decidual cells. Reactivity with PHA-E, demonstrating complex carbohydrates, was most intense in the mesometrial decidua closest to the trophoblastic giant cells and may demonstrate glycoconjugates involved in maintaining integrity at this maternotrophoblast interface. Lectins derived from Helix pomatia (HPA), Vicia villosa (VVA), Glycine max (SBA) and Arachis hypogaea (PNA) reacted only with occasional small cells in antimesometrial or mesometrial decidua, probably demonstrating alpha and/ or beta-linked N-acetylgalactosamine residues on lymphocytes or monocytes. The glycoprotein granules of granulated metrial gland (GMG) cells in the decidua basalis and the metrial gland reacted strongly with WGA, MPA and PHA-L demonstrating complex carbohydrates including sialic acid residues and tri/tetra-antennary, nonbisected N-linked glycans. GMG cell cytoplasm reacted diffusely with Con A, LcH, PSA, WGA, PHA-E and PHA-L. In some GMG cells reactivity with WGA was apparently localised to the Golgi region indicating involvement in granule formation. Pericellular reactivity of some GMG cells with WGA may relate to migratory activity. The lectin reactivity of fibroblast-like stromal cells in the material gland was similar to that of the extracellular matrix and it is likely that many matrix molecules are produced by the stromal cells. A range of lectins (Con A, LcH, PSA, GS-II GS-I and PHA-L) reacted with some blood vessels in the metrial gland at day 12 of pregnancy: this may indicate activation changes associated with the transendothelial passage of GMG cells at this stage. Lectins derived from Dolichos biflorus (DBA), Bauhinia purpurea (BPA), Lotus tetragonolobus (LTA) and Ulex europaeus-I (UEA-I) did not react with decidual and metrial gland regions. Lectin binding profile studies can provide further information on the events occurring in the uterus in pregnancy: investigations at the ultrastructural level are required to resolve further intra and extracellular changes. PMID:8655407

Peel, S; Bulmer, J N



Sexual reinforcement in the female rat  

Microsoft Academic Search

Sexual reinforcement in the female rat was studied in a preparation that allowed continuous operant responding for access to a male rat leading to intromission. Experiment 1 used a high operant level nose-poke response to test the possible reinforcing effects of some components of access to a male. A simple tone stimulus used as a conditioned reinforcer and two odor




Brain oxytocin: differential inhibition of neuroendocrine stress responses and anxiety-related behaviour in virgin, pregnant and lactating rats  

Microsoft Academic Search

The involvement of brain oxytocin in the attenuated responsiveness of the hypothalamo-pituitary–adrenal axis and the oxytocin systems to external stressors found in pregnant and lactating rats has been studied, including both neuroendocrine and behavioural aspects. Intracerebroventricular infusion of an oxytocin receptor antagonist (0.75?g\\/5?l), but not of vehicle, elevated basal corticotropin and corticosterone secretion into blood of virgin female, but not

I. D. Neumann; L. Torner; A. Wigger



Effects of leucine supplemented diet on intestinal absorption in tumor bearing pregnant rats  

Microsoft Academic Search

BACKGROUND: It is known that amino acid oxidation is increased in tumor-bearing rat muscles and that leucine is an important ketogenic amino acid that provides energy to the skeletal muscle. METHODS: To evaluate the effects of a leucine supplemented diet on the intestinal absorption alterations produced by Walker 256, growing pregnant rats were distributed into six groups. Three pregnant groups

Gislaine Ventrucci; Maria Alice Roston de Mello; Maria Cristina Cintra Gomes-Marcondes



A BBDR-HPT Axis Model for the Pregnant Rat and Fetus: Evaluation of Iodide Deficiency  

EPA Science Inventory

A biologically based dose response (BBDR) model for the hypothalamic-pituitarythyroid (HPT) axis for the pregnant rat and fetus is being developed to advance understanding of thyroid hormone disruptions and developmental neurotoxicity (DNT). The model for the pregnant rat and fet...



EPA Science Inventory

Atrazine (ATR) is a widely used herbicide shown to delay early mammary development in female offspring of gestationally exposed rats. The effects of ATR can be induced by in utero exposure and/or suckling from a dam exposed during late pregnancy, but ATR is reported to have a hal...


The effects of spaceflight on mammary metabolism in pregnant rats  

NASA Technical Reports Server (NTRS)

The effects of spaceflight on mammary metabolism of 10 pregnant rats was measured on Day 20 of pregnancy and after parturition. Rats were flown on the space shuttle from Day 11 through Day 20 of pregnancy. After their return to earth, glucose oxidation to carbon dioxide increased 43% (P < 0.05), and incorporation into fatty acids increased 300% (P < 0.005) compared to controls. It is unclear whether the enhanced glucose use is due to spaceflight or a response to landing. Casein mRNA and gross histology were not altered at Day 20 of pregnancy. Six rats gave birth (on Day 22 to 23 of pregnancy) and mammary metabolic activity was measured immediately postpartum. The earlier effects of spaceflight were no longer apparent. There was also no difference in expression of beta-casein mRNA. It is clear from these studies that spaceflight does not impair the normal development of the mammary gland, its ability to use glucose, nor the ability to express mRNA for a major milk protein.

Plaut, K.; Maple, R.; Vyas, C.; Munaim, S.; Darling, A.; Casey, T.; Alberts, J. R.



Hepatic microsomal drug metabolism in the pregnant rat.  


1. Hepatic microsomal drug metabolism determined with the substrates aniline (p-hydroxylation), ethylmorphine (N-demethylation) and p-nitrobenzoic acid (reduction), decreased during gestation in the rat to 53-73% of non-pregnant control levels by day 20 of gestation. 2. Enzyme activity remained low at one day post-partum, but had returned to control non-pregnant levels by five days post-partum. 3. The total capacity of the liver to metabolize drugs remained unchanged or increased because liver weight was increased by up to 40% during pregnancy. 4. Changes in drug metabolism were not related to alterations in the concentration, substrate-induced binding affinity (Ks) or maximal spectral change (delta Amax) of cytochrome P-450. 5. Alterations in hepatic drug metabolism are possibly mediated via changes in microsomal phospholipids and/or the cytochrome P-450 spin-state equilibrium as as pregnancy was associated with a decrease in (a) microsomal total phospholipids, (b) the phosphatidylcholine to phosphatidylethanolamine ratio and (c) the high-spin form of ferricytochrome P-450. PMID:7136004

Symons, A M; Turcan, R G; Parke, D V



Susceptibility of fetal, virgin, pregnant and lactating rats for the induction of mammary tumors by gamma rays  

SciTech Connect

Pregnant Wistar-MS rats received a whole-body irradiation of 0-2.6 Gy {gamma} rays at day 20 of pregnancy. The mother rats were implanted with a diethylstilbestrol (DES) pellet 30 days after weaning, and the female pups delivered by the irradiated mother were treated with DES after maturation. Lactating rats were irradiated with {gamma} rays 21 days after parturition and then treated with DES. Virgin rats 70 days of age were also irradiated and then administered DES. The rats which received intrauterine irradiation did not develop mammary tumors in the mother rats and lactating rats increased in a dose-dependent manner with increasing doses of {gamma} rays up to 2.1 Gy. With 0.1-1 Gy, the incidence of adenocarcinoma in the mother rats was significantly lower than that observed in the lactating rats. However, the incidence in the mother rats irradiated with 1.0-1.5 Gy was significantly higher than that of virgin rats treated with the corresponding {gamma}-ray doses. These findings suggest that the susceptibility of the mammary glands to radiation depends upon the differentiation at the time of exposure. 22 refs., 4 figs., 2 tabs.

Inano, Hiroshi; Suzuki, Heiko; Onoda, Makoto; Yamanouchi, Hiroshi [National Institute of Radiological Sciences, Inage-ku, Chiba-shi (Japan)



The effect of morphine consumption on plasma corticosteron concentration and placenta development in pregnant rats  

PubMed Central

Background: Previous studies have shown that morphine consumption during pregnancy may delay embryo development or cause abnormal nervous system function. Objective: The present study focused on the effect of maternal morphine consumption on development of placenta and blood corticosteron concentration in addictive pregnant mothers. Materials and Methods: 24 female rats, 170-200g weight, were used. The experimental groups after pregnancy received an oral dose of 0.05 mg/ml of morphine by tap water while the control group received only tap water. On 10th and 14th day of pregnancy, rats were anesthetized and placenta removed surgically, 1ml blood was collected from each pregnant mother from retro-orbital sinus, the concentration of blood corticosteron was determined by corticosteron Elisa kit after centrifugation. The fixed tissue was processed, sectioned and stained with hematoxylin and eosin. Placenta was studied microscopically according to the thickness of layers, area of blood cisterns, and the number of cells. Results: Comparing the plasma corticosteron concentration of the treatment and the control groups, not only a severe increase in the treatment group was detected, but also the thickness of maternal and embryonic portions of the placenta at day 10th and 14th of gestation was different significantly (p?0.05). Furthermore, an increase in number of cells in maternal and embryonic portion of placenta and a decrease in blood cistern area were demonstrated in both the experimental and the control groups. Conclusion: The effects of morphine, including an increase in blood concentration of corticosteron, in dependent pregnant mothers were seen. Development of placenta in the experimental group was delayed.

Kazemi, Masoomeh; Sahraei, Hedayat; Azarnia, Mahnaz; Dehghani, Leila; Bahadoran, Hossein; Tekieh, Elaheh



Prenatal Exposure to Nicotine in Pregnant Rat Increased Inflammatory Marker in Newborn Rat  

PubMed Central

This study aimed to investigate any inflammatory effect of nicotine on rat embryo by exposing their mothers to different dosages of nicotine during pregnancy. During this experimental study, 32 pregnant healthy Wistar rats were divided into 4 equal groups, including a control and 3 nicotine exposure groups. Injections were performed subcutaneously starting at the first day of pregnancy until parturition. As the dosages of nicotine were increased, the weight gain by pregnant rats and the mean weight of their newborns were significantly reduced. Mean ± SD of hs-CRP was significantly higher among groups exposed to various dosages of nicotine (2, 4, and 6?mg/kg) compared to the control group (P < 0.0001) and its increasing rate was also dose dependent. Mean ± SD serum level of IL-6 and TNF-? among all groups exposed to nicotine, except for 2?mg/kg nicotine injected group, was increased significantly (P < 0.0001). Mean ± SD of serum level of TGF-? and nitrite oxide among exposure groups showed significant differences compared to the control group only at the dosage of 6?mg/kg (P < 0.0001). The current study showed that exposing pregnant rats to nicotine causes a dose dependent increase in the rate of all the studied inflammatory serum markers among their newborns. PMID:25242867

Mohsenzadeh, Yosouf; Rahmani, Asghar; Cheraghi, Javad; Pyrani, Maryam



An evaluation of the teratogenic potential of protracted exposure of pregnant rats to 2450?MHz microwave radiation. II. postnatal psychophysiologic analysis  

Microsoft Academic Search

The objective of this study was to determine whether protracted prenatal exposure of rats to 2450?MHz microwave radiation at a power density level of 20 mW\\/cm would significantly alter postnatal growth and psychophysiologic development. Of 75 pregnant rats, 12 were exposed to microwave radiation, 4 sham?irradiated, and 59 served as environmental control animals. Forty?five females were allowed to deliver their

Ronald P. Jensh; Wolfgang H. Vogel; Robert L. Brent



Effects of dibutyl phthalate on reproductive function in pregnant and pseudopregnant rats  

Microsoft Academic Search

In our previous studies, dibutyl phthalate (DBP) was found to be embryolethal and teratogenic in rats. In this study, the effects of DBP on reproductive function were investigated on pregnant and pseudopregnant rats. Rats were given DBP by gastric intubation at 0, 250, 500, 750, 1000, 1250 or 1500 mg\\/kg on Days 0 to 8 of pregnancy and the pregnancy

Makoto Ema; Emiko Miyawaki; Kunio Kawashima



The UF Family of hybrid phantoms of the pregnant female for computational radiation dosimetry.  


Efforts to assess in utero radiation doses and related quantities to the developing fetus should account for the presence of the surrounding maternal tissues. Maternal tissues can provide varying levels of protection to the fetus by shielding externally-emitted radiation or, alternatively, can become sources of internally-emitted radiation following the biokinetic uptake of medically-administered radiopharmaceuticals or radionuclides located in the surrounding environment--as in the case of the European Union's SOLO project (Epidemiological Studies of Exposed Southern Urals Populations). The University of Florida had previously addressed limitations in available computational phantom representation of the developing fetus by constructing a series of hybrid computational fetal phantoms at eight different ages and three weight percentiles. Using CT image sets of pregnant patients contoured using 3D-DOCTOR(TM), the eight 50th percentile fetal phantoms from that study were systematically combined in Rhinoceros(TM) with the UF adult non-pregnant female to yield a series of reference pregnant female phantoms at fetal ages 8, 10, 15, 20, 25, 30, 35 and 38?weeks post-conception. Deformable, non-uniform rational B-spline surfaces were utilized to alter contoured maternal anatomy in order to (1) accurately position and orient each fetus and surrounding maternal tissues and (2) match target masses of maternal soft tissue organs to reference data reported in the literature. PMID:25030913

Maynard, Matthew R; Long, Nelia S; Moawad, Nash S; Shifrin, Roger Y; Geyer, Amy M; Fong, Grant; Bolch, Wesley E



The UF Family of hybrid phantoms of the pregnant female for computational radiation dosimetry  

NASA Astrophysics Data System (ADS)

Efforts to assess in utero radiation doses and related quantities to the developing fetus should account for the presence of the surrounding maternal tissues. Maternal tissues can provide varying levels of protection to the fetus by shielding externally-emitted radiation or, alternatively, can become sources of internally-emitted radiation following the biokinetic uptake of medically-administered radiopharmaceuticals or radionuclides located in the surrounding environment—as in the case of the European Union’s SOLO project (Epidemiological Studies of Exposed Southern Urals Populations). The University of Florida had previously addressed limitations in available computational phantom representation of the developing fetus by constructing a series of hybrid computational fetal phantoms at eight different ages and three weight percentiles. Using CT image sets of pregnant patients contoured using 3D-DOCTORTM, the eight 50th percentile fetal phantoms from that study were systematically combined in RhinocerosTM with the UF adult non-pregnant female to yield a series of reference pregnant female phantoms at fetal ages 8, 10, 15, 20, 25, 30, 35 and 38?weeks post-conception. Deformable, non-uniform rational B-spline surfaces were utilized to alter contoured maternal anatomy in order to (1) accurately position and orient each fetus and surrounding maternal tissues and (2) match target masses of maternal soft tissue organs to reference data reported in the literature.

Maynard, Matthew R.; Long, Nelia S.; Moawad, Nash S.; Shifrin, Roger Y.; Geyer, Amy M.; Fong, Grant; Bolch, Wesley E.



Testosterone and muscle hypertrophy in female rats  

NASA Technical Reports Server (NTRS)

The effects of chronic treatment with testosterone propionate (TP) on compensatory muscle hypertropy in female rats are examined. The 48 female rats were placed in one of four test groups: (1) no overload (synergist removal), no TP, (2) overload, no TP, (3) no overload + TP, and (4) overload + TP. The technique used to administer the TP is described. The preparation of the plantaris muscle, the analysis of pyruvate oxidation and the determination of malate and lactate dehydrogenases and the noncollogen protein are explained. The results which reveal the effect of overload and TP on body weight, noncollogen protein concentration, lactate and malate dehydrogenase activities, and pyruvate oxidation are presented and discussed. It is concluded that in terms of body weight, protein content, pyruvate, glycolysis, and oxidative metabolisms chronic TP treatments do not change compensatory muscle hypertropy.

Kuhn, F. E.; Max, S. R.



Heme Oxygenase Inhibition Increases Blood Pressure in Pregnant Rats  

PubMed Central

Background During normal gestation, the placenta is a relatively hypoxic organ and, as such, is subject to significant oxidative stress. In the preeclamptic patient, inadequate remodeling of the maternal vasculature severely exacerbates placental oxidative stress, which has been shown to be an important component of maternal hypertension. There is emerging evidence that Heme Oxygenase-1 (HO-1) acts as an important regulator of placental and cardiovascular function during normal pregnancy. Here, we have examined the effect of Heme Oxygenase (HO) inhibition in late gestation on maternal blood pressure, angiogenic balance, and placental oxidative stress in pregnant rats. Methods HO activity was inhibited with tin mesoporphyrin (SnMP), which was administered on gestational day 14, and blood pressure was measured on gestational day 19. Placental angiogenic balance and plasma Vascular Endothelial Growth Factor (VEGF) were determined by sandwich enzyme-linked immunosorbent assay. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was measured by lucigenin chemilluminescence. Results In response to SnMP treatment, maternal mean arterial pressure (MAP) was significantly increased (99±1 vs. 113±2mm Hg; P < 0.05; n = 15 per group). Placental soluble fms-like tyrosine kinase-1 (sFlt-1) (631±47 vs. 648±26 pg/mg; P = 0.76) levels in the placenta were not affected by HO inhibition. Additionally, there was no significant difference in free VEGF in the maternal circulation (287±22 vs. 329±14 pg/ml; P = 0.11). There was, however, a significant decrease in placental VEGF (23±2 vs. 16±1 pg/mg; P < 0.05) and a significant increase in placental NADPH oxidase activity in SnMP-treated rats (2021±238 vs. 3005±301 RLU/min/mg; P < 0.05). Conclusions Our results demonstrate that HO is an important regulator of blood pressure and an important antioxidant in the developing placenta. PMID:23553216



Protective effect of Petroselinum crispum extract in abortion using prostadin-induced renal dysfunction in female rats  

PubMed Central

Objective: Present study investigated the effects of parsley extract on pregnant rat kidneys which have undergone clinical abortion using prostaglandins. The renal protective effect of parsley extract was evaluated in pregnant rats which had an abortion. Parsley was used due to its antioxidant properties. Materials and Methods: Fifty-four female rats were divided in 9 groups of 6: control pregnant, two pregnant groups which received parsley extract and prostadin, two non-pregnant groups treated with parsley extract and prostadin, a group administered with both treatments, and three groups which received parsley extract in pre-implantation, implantation, and post-implantation periods of embryos. Ethanolic extract (5 mg/kg) was given daily to animals for 18 days of pregnancy period. Parameters such as malondialdehyde (MDA), total antioxidant statues (TAS), creatinine, and urea were measured using biochemical assays. Histopathologic studies were also done with Hematoxylin-Eosin staining method. Results: After 18 days of treatment, significant differences were observed in serum creatinine, urea, and MDA and TAS levels. Kidney cross-sections showed edema in prostadin-treated rats while improvements in parsley + prostadin -treated rats were observed. Conclusion: These results suggested that ethanolic extract of Petroselinum crispum reduced the dysfunction in rats kidney caused by prostadin-induced abortion and could have beneficial effect in reducing the progression of prostaglandin-induced edema. PMID:25386393

Rezazad, Maryam; Farokhi, Farah



Effect of thienorphine on the isolated uterine strips from pregnant rats.  


Opioid dependence is a serious worldwide health problem. Buprenorphine was used as an alternative to methadone for the treatment of opioid dependence, especially for pregnant women. Thienorphine was a partial opioid agonist with long-lasting antinociceptive effect and high oral bioavailability compared with its analogue buprenorphine. Till now, there was still no research about the effect of thienorphine on the isolated uterine muscles. This study examined the effects of thienorphine on the isolated rat oestrus and pregnant uterine strips. Area under the curve (AUC), amplitude and frequency were studied. Thienorphine induced a concentration-dependent decrease in the frequency and amplitude of the contraction on the isolated oestrus and pregnant uterine strips. Thienorphine exhibited less inhibition on the contractile amplitude of the isolated uterine strips from pregnant rats with the IC50 of 54.11 ± 7.41 ??, compared with buprenorphine (IC50, 19.42 ± 2.34 ??). In addition, thienorphine also exhibited less inhibition on the contractile frequency of the isolated uterine strips from pregnant rats, with the IC50 of 70.68 ± 12.44 ??, compared with buprenorphine (IC50, 19.20 ± 3.87 ??). On the isolated uterine muscle from pregnant rats, the AUC was decreased by thienorphine but was less potent than buprenorphine, the IC50 was 37.31 ± 7.43 ?? for thienorphine and 13.52 ± 2.03 ?? for buprenorphine. Thienorphine exhibited longer duration on the isolated rat pregnant uterine strips than buprenorphine. Thienorphine has less influence and longer duration on the isolated rat uterine muscles during pregnancy, which may be a new useful candidate for the opioid dependent pregnant women. PMID:23416213

Zhou, Peilan; Yan, Lingdi; Yong, Zheng; Yu, Gang; Dong, Huajin; Yan, Hui; Su, Ruibin; Gong, Zehui



Biotransformation of 2,3,3,3-tetrafluoropropene (HFO-1234yf) in male, pregnant and non-pregnant female rabbits after single high dose inhalation exposure  

SciTech Connect

2,3,3,3-Tetrafluoropropene (HFO-1234yf) is a novel refrigerant intended for use in mobile air conditioning. It showed a low potential for toxicity in rodents studies with most NOAELs well above 10,000 ppm in guideline compliant toxicity studies. However, a developmental toxicity study in rabbits showed mortality at exposure levels of 5,500 ppm and above. No lethality was observed at exposure levels of 2,500 and 4,000 ppm. Nevertheless, increased subacute inflammatory heart lesions were observed in rabbits at all exposure levels. Since the lethality in pregnant animals may be due to altered biotransformation of HFO-1234yf and to evaluate the potential risk to pregnant women facing a car crash, this study compared the acute toxicity and biotransformation of HFO-1234yf in male, female and pregnant female rabbits. Animals were exposed to 50,000 ppm and 100,000 ppm for 1 h. For metabolite identification by {sup 19}F NMR and LC/MS-MS, urine was collected for 48 h after inhalation exposure. In all samples, the predominant metabolites were S-(3,3,3-trifluoro-2-hydroxypropanyl)-mercaptolactic acid and N-acetyl-S-(3,3,3-trifluoro-2-hydroxypropanyl)-L-cysteine. Since no major differences in urinary metabolite pattern were observed between the groups, only N-acetyl-S-(3,3,3-trifluoro-2-hydroxypropanyl)-L-cysteine excretion was quantified. No significant differences in recovery between non-pregnant (43.10 ± 22.35 ?mol) and pregnant female (50.47 ± 19.72 ?mol) rabbits were observed, male rabbits exposed to 100,000 ppm for one hour excreted 86.40 ± 38.87 ?mol. Lethality and clinical signs of toxicity were not observed in any group. The results suggest that the lethality of HFO-1234yf in pregnant rabbits unlikely is due to changes in biotransformation patterns or capacity in pregnant rabbits. -- Highlights: ? No lethality and clinical signs were observed. ? No differences in metabolic pattern between pregnant and non-pregnant rabbits. ? Rapid and similar metabolite excretion in all groups. ? Very low amount of biotransformation in all groups (< 0.1%).

Schmidt, Tobias [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany)] [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany); Bertermann, Rüdiger [Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg (Germany)] [Institut für Anorganische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg (Germany); Rusch, George M. [Honeywell, P.O. Box 1057, Morristown, NJ 07962–1057 (United States)] [Honeywell, P.O. Box 1057, Morristown, NJ 07962–1057 (United States); Hoffman, Gary M. [Huntingdon Life Sciences., East Millstone, NJ (United States)] [Huntingdon Life Sciences., East Millstone, NJ (United States); Dekant, Wolfgang, E-mail: [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany)] [Institut für Toxikologie, Universität Würzburg, Versbacher Str. 9, 97078 Würzburg (Germany)



Effect of Transverse Aortic Constriction on Cardiac Structure, Function and Gene Expression in Pregnant Rats  

PubMed Central

Background There is an increased risk of heart failure and pulmonary edema in pregnancies complicated by hypertensive disorders. However, in a previous study we found that pregnancy protects against fibrosis and preserves angiogenesis in a rat model of angiotensin II induced cardiac hypertrophy. In this study we test the hypothesis that pregnancy protects against negative effects of increased afterload. Methods Pregnant (gestational day 5.5–8.5) and non-pregnant Wistar rats were randomized to transverse aortic constriction (TAC) or sham surgery. After 14.2±0.14 days echocardiography was performed. Aortic blood pressure and left ventricular (LV) pressure-volume loops were obtained using a conductance catheter. LV collagen content and cardiomyocyte circumference were measured. Myocardial gene expression was assessed by real-time polymerase chain reaction. Results Heart weight was increased by TAC (p<0.001) but not by pregnancy. Cardiac myocyte circumference was larger in pregnant compared to non-pregnant rats independent of TAC (p?=?0.01), however TAC per se did not affect this parameter. Collagen content in LV myocardium was not affected by pregnancy or TAC. TAC increased stroke work more in pregnant rats (34.1±2.4 vs 17.5±2.4 mmHg/mL, p<0.001) than in non-pregnant (28.2±1.7 vs 20.9±1.5 mmHg/mL, p?=?0.06). However, it did not lead to overt heart failure in any group. In pregnant rats, ?-MHC gene expression was reduced by TAC. Increased in the expression of ?-MHC gene was higher in pregnant (5-fold) compared to non-pregnant rats (2-fold) after TAC (p?=?0.001). Nine out of the 19 genes related to cardiac remodeling were affected by pregnancy independent of TAC. Conclusions This study did not support the hypothesis that pregnancy is cardioprotective against the negative effects of increased afterload. Some differences in cardiac structure, function and gene expression between pregnant and non-pregnant rats following TAC indicated that afterload increase is less tolerated in pregnancy. PMID:24586871

Songstad, Nils Thomas; Johansen, David; How, Ole-Jacob; Kaaresen, Per Ivar; Ytrehus, Kirsti; Acharya, Ganesh



Effects of leucine supplemented diet on intestinal absorption in tumor bearing pregnant rats  

PubMed Central

Background It is known that amino acid oxidation is increased in tumor-bearing rat muscles and that leucine is an important ketogenic amino acid that provides energy to the skeletal muscle. Methods To evaluate the effects of a leucine supplemented diet on the intestinal absorption alterations produced by Walker 256, growing pregnant rats were distributed into six groups. Three pregnant groups received a normal protein diet (18% protein): pregnant (N), tumor-bearing (WN), pair-fed rats (Np). Three other pregnant groups were fed a diet supplemented with 3% leucine (15% protein plus 3% leucine): leucine (L), tumor-bearing (WL) and pair-fed with leucine (Lp). Non pregnant rats (C), which received a normal protein diet, were used as a control group. After 20 days, the animals were submitted to intestinal perfusion to measure leucine, methionine and glucose absorption. Results Tumor-bearing pregnant rats showed impairment in food intake, body weight gain and muscle protein content, which were less accentuated in WL than in WN rats. These metabolic changes led to reduction in both fetal and tumor development. Leucine absorption slightly increased in WN group. In spite of having a significant decrease in leucine and methionine absorption compared to L, the WL group has shown a higher absorption rate of methionine than WN group, probably due to the ingestion of the leucine supplemented diet inducing this amino acid uptake. Glucose absorption was reduced in both tumor-bearing groups. Conclusions Leucine supplementation during pregnancy in tumor-bearing rats promoted high leucine absorption, increasing the availability of the amino acid for neoplasic cells and, mainly, for fetus and host utilization. This may have contributed to the better preservation of body weight gain, food intake and muscle protein observed in the supplemented rats in relation to the non-supplemented ones. PMID:11955290

Ventrucci, Gislaine; de Mello, Maria Alice Roston; Gomes-Marcondes, Maria Cristina Cintra



Short and long effects of Citrullus colocynthis L. on reproductive system and fertility in female Spague-Dawley rats.  


Aim of this study is to investigate the toxic effects of Citrullus colocynthis L. (400 mg/kg/body wight) on the reproductive system after administration to female Sprague-Dawley rats weighting 250-300 g for two time periods 4 and 12 weeks. Twenty adult female rats were divided into two groups and Citrullus colocynthis L. were intraperitoneally injected to experimental animals in dose of 400 mg/kg/body wight. First group containing 10 rats received treatment for 4 weeks and a second group of 10 rats received the same dose of treatment for a period of 12 weeks and compared with twenty non-exposed female rats received vehicle treatment. Female rats were allowed mating with males after 10 days prior to the last administration dose. Animals were autopsied under light anesthesia after mating and several parameters were determined including: number of pregnant rats, body and reproductive organ weight, number of implantation sites, viable fetuses and resorption sites. Assessment of pregnancies in females was measured and the significance of these results was calculated using students t and Chi-square tests. The effect of Citrullus colocynthis L. exposure on fertility was assessed in terms of pregnant rats number, implantation sites, viable fetuses and resorption sites. Exposure to Citrullus colocynthis L. for 4 weeks did not have much effect on fertility. Significant decrease in the relative ovarian weights and embryo weights in rats exposed to Citrullus colocynthis L. were observed. Exposure to Citrullus colocynthis L. for a 12 weeks resulted in a reduction in the percentage of pregnancies and in the number of implantation sites when compared with controls in both treatment periods. Rats receiving 12 weeks treatment showed a decrease in ovarian weights and a decrease in viable fetus's number. These results indicate that long-term exposure of female rats to Citrullus colocynthis L. causes adverse effects on the reproductive system and fertility. PMID:19070085

Qazan, Walid Sh; Almasad, Motasem M; Daradka, Haytham



Does L-arginine availability during the early pregnancy alters the immune response of Trypanosoma cruzi infected and pregnant Wistar rats?  


Chagas disease induces a strong immune response and L-arginine is an essential amino acid which plays an important role in homeostasis of the immune system. The aims of this study were to evaluate parasitemia, corticosterone levels, production of nitric oxide (NO), fetal morphological measurements, and histology of heart and placenta. Twenty pregnant Wistar rats (180-220 g) were grouped in: pregnant control (PC), pregnant control and L-arginine supplied (PCA), pregnant infected (PI), pregnant infected and L-arginine supplied (PIA). Females were infected with 1×10(5) trypomastigotes of the Y strain (3rd day of pregnancy). Animals were supplied with 21 mg of L-arginine/kg/day during 14 days. PIA showed significant decreased levels of corticosterone and parasitemia. For control groups, any alteration in NO production was found with L-arginine supplementation; for PIA, enhanced nitrite concentrations were observed as compared to PI. Weights and lengths of fetuses were higher in L-arginine treated and infected pregnant rats as compared to untreated ones. Placental weight from the PIA group was significantly increased when compared to PI. In L-arginine treated animals, cardiac tissue showed reduced amastigote burdens. PIA and PI displayed similar placental parasitism. Based on these results, L-arginine supplementation may be potentially useful for the protection against Trypanosoma cruzi during pregnancy. PMID:24786713

da Costa, Cássia Mariana Bronzon; de Freitas, Murilo Rodrigues Barbosa; Brazão, Vânia; dos Santos, Carla Domingues; Sala, Miguel Angel; do Prado Júnior, José Clovis; Abrahão, Ana Amélia Carraro



Effect of Asparagus racemosus rhizome (Shatavari) on mammary gland and genital organs of pregnant rat.  


Asparagus racemosus (AR) Willd (family Liliaceae) is commonly known as Shatavari. The alcoholic extract of its rhizome was administered orally to adult pregnant female albino rats at a dose of 30 mg/100 g body weight, daily for 15 days (days 1-15 of gestation). The macroscopic findings revealed a prominence of the mammary glands, a dilated vaginal opening and a transversely situated uterine horn in the treated group of animals. The weight of the uterine horns of the treated group was found to be significantly higher (p < 0.001) but the length was shorter (p > 0.01). Microscopic examination of the treated group showed proliferation in the lumen of the duct of mammary gland. It was obliterated due to hypertrophy of ductal and glandular cells. Hyperplasia of the glandular and muscular tissue and hypertrophy of the glandular cells were observed in the genital organs. The parenchyma of the genital organs showed abundant glycogen granules with dilated blood vessels and thickening of the epithelial lining. The oviduct in the treated group showed hypertrophied muscular wall, whereas the ovary revealed no effect of the drug. The results suggest an oestrogenic effect of Shatavari on the female mammary gland and genital organs. PMID:16177978

Pandey, S K; Sahay, A; Pandey, R S; Tripathi, Y B



Green tea extract increases mRNA expression of enzymes which influence epigenetic marks in newborn female offspring from undernourished pregnant mother.  


Biochemical and toxicological properties of catechin remain unclear, e.g.; how catechin affects female offspring from undernourished pregnant dams. Here, to elucidate effects of low prenatal protein on female offspring health status, changes of enzymes which modify epigenetic marks related with metabolism in kidneys from newborns were investigated after continuously administering catechin extracted from green tea to lactating maternal rats after pregnant undernourishment. We found that green tea extract intake during lactation up-regulated the activation of AMP-activated protein kinase in young female offspring from protein-restricted dams and modulated the AMP-activated protein kinase pathway in the kidney. This pathway was indicated to be stimulated by SIRT1 gene expression. The feeding of green tea extract to protein-restricted dams during lactation is likely to up-regulate AMP-activated protein kinase activation and may partly lead to alterations of the AMP-activated protein kinase pathway in female offspring kidneys. In addition, energy metabolism in fetal and offspring period with green tea extract administration might be related to enzymes which modify epigenetic marks such as DNA methyltransferase 1 and 3a. PMID:24009774

Sun, Yongkun; Mukai, Yuuka; Tanaka, Masato; Saito, Takeshi; Sato, Shin; Kurasaki, Masaaki



Coronary Flow Reserve in Pregnant Rats with Increased Left Ventricular Afterload  

PubMed Central

Background Coronary flow reserve (CFR) is used as a measure of coronary endothelial function. We investigated the effect of increased afterload on CFR of pregnant and non-pregnant rats. Methods Afterload increase in Wister rats (both pregnant and non-pregnant) was achieved by the infusion of angiotensin II (Ang II) for ?10 days or by subjecting them to transverse aortic constriction (TAC) for ?14 days. Control groups were infused with 0.9% NaCl or had sham surgery, respectively. In pregnant rats, the experiments were performed close to term gestation. Doppler velocity waveforms of the left main coronary artery were recorded using a high resolution ultrasound imaging system (Vevo 770, VisualSonics, Canada) at baseline while the animals were anesthetized with 1.5% inhaled isoflurane, and during maximal coronary dilatation obtained by the inhalation of 3.5% of isoflurane. CFR was calculated as the ratio between the peak coronary flow velocities (CFRpeak) and the velocity-time integrals (CFRVTI) recorded at hyperemia and at baseline. Results CFR could be calculated in 60 of 75 (80%) animals. There were no differences in CFR between intervention and control groups irrespective of whether afterload was increased by Ang II or TAC. In the TAC-study CFRpeak (1.54±0.07 vs 1.85±0.17; p?=?0.03) was decreased in pregnant compared to non-pregnant shams. When sham animals from both studies were pooled together both CFRpeak (1.42±0.07 vs 1.86±0.16; p?=?0.005) as well as CFRVTI (1.45±0.07 vs 1.78±0.12; p?=?0.03) were significantly lower in pregnant rats compared to non-pregnant. Conclusions CFR can be measured non-invasively in rats using Doppler echocardiography and high concentrations of inhaled isoflurane as a coronary vasodilator. In pregnant rats, CFR is reduced close to term. CFR is not affected by increased left ventricular afterload caused by chronic Ang II infusion or TAC. PMID:25007056

Songstad, Nils Thomas; Serrano, Maria C.; Sitras, Vasilis; Johansen, Davis; Ytrehus, Kirsti; Acharya, Ganesh




EPA Science Inventory

The hypothesis that hepatic metallothionein (MT) induction in the pregnant animal results in a Zn deficiency in the embryo was tested by treating pregnant rats with a-hederin, reported to induce MT in rat liver. orphological development was assessed in term fetuses. ingle dose of...


Effects of low doses of alcohol on delta-9-tetrahydrocannabinol's effects in pregnant rats  

SciTech Connect

Pregnant rats were intubated with 50 mg/kg of delta-9-tetrahydrocannabinol (THC) or with THC plus alcohol to determine if a low dose of alcohol would significantly increase blood levels of THC. On the basis of this study, a second study was conducted in which pregnant rats were intubated with THC plus alcohol from gestation day six to parturition. THC reduced birth weights but did not significantly affect litter size or passive avoidance learning. Alcohol did not have a significant effect on offspring birth weight nor did it interact with THC to affect offspring.

Abel, E.L.; Subramanian, M.G. (Wayne State Univ., Detroit, MI (USA))



Modest maternal protein restriction fails to program adult hypertension in female rats.  


Modest maternal dietary protein restriction in the rat leads to hypertension in adult male offspring. The purpose of this study was to determine whether female rats are resistant to developing the increased blood pressure seen in male rats after maternal protein restriction. Pregnant rats were fed a normal protein (19%, NP) or low-protein (8.5%, LP) diet throughout gestation. Renal renin protein and ANG II levels were reduced by 50-65% in male LP compared with NP pups, but were not suppressed in female LP compared with female NP. Mean arterial pressure in conscious, chronically instrumented adult female offspring (22 wk) was not different in LP (LP: 120 +/- 3 mmHg vs. NP: 121 +/- 2 mmHg), and glomerular filtration rate was also not different in LP vs. NP. The number of glomeruli per kidney was similar in adult LP and NP female offspring (LP: 26,050 +/- 2,071 vs. NP: 26,248 +/- 1,292, NP), and individual glomerular volume was also not different (LP: 0.92 +/- 0.11 10(6) microm(3), LP vs. NP: 1.07 +/- 0.11 10(6) microm(3)); the total volume of all glomeruli per kidney was also not significantly different. Thus female rats are relatively resistant to the programming for adult hypertension by perinatal protein restriction that we have described in males. This resistance may be due to the fact that modest maternal protein restriction does not reduce the number of glomeruli with which females are endowed as it does in males. The intrarenal renin-angiotensin system during development may play a key role in this protective effect of female gender. PMID:15961538

Woods, Lori L; Ingelfinger, Julie R; Rasch, Ruth



Oxytocin regulates the expression of aquaporin 5 in the late-pregnant rat uterus.  


Aquaporins (AQPs) are integral membrane channels responsible for the transport of water across a cell membrane. Based on reports that AQPs are present and accumulate in the female reproductive tract late in pregnancy, our aim was to study the expression of AQP isoforms (AQP1, 2, 3, 5, 8, and 9) at the end of pregnancy in rat in order to determine if they play a role in parturition. Reverse-transcriptase PCR revealed that specific Aqp mRNAs were detectable in the myometrium of non-pregnant and late-pregnancy (Days 18, 20, 21, and 22 of pregnancy) rat uteri. The expression of Aqp5 mRNA and protein were most pronounced on Days 18-21, and were dramatically decreased on Day 22 of pregnancy. In contrast, a significant increase was found in the level of Aqp5 transcript in whole-blood samples on the last day of pregnancy. The effect of oxytocin on myometrial Aqp5 expression in an organ bath was also investigated. The level of Aqp5 mRNA significantly decreased 5 min after oxytocin (10(-8) M) administration, similarly to its profile on the day of delivery; this effect was sensitive to the oxytocin antagonist atosiban. The vasopressin analog desmopressin (3.7 × 10(-8) M), on the other hand, did not alter the expression of Aqp5, but did increased the amount of Aqp2 mRNA, an effect that was atosiban-resistant. These results lead us to propose that oxytocin selectively influences the expression of Aqp5 at the end of pregnancy, and may participate in events that lead to parturition in the rat. The sudden increase of AQP5 in the blood on the last day of pregnancy may serve as a marker that indicates the initiation of delivery. PMID:24644013

Ducza, Eszter; Seres, Adrienn B; Hajagos-Tóth, Judit; Falkay, George; Gáspár, Róbert



Thermal physiology of pregnant and lactating female and male long-eared bats, Nyctophilus geoffroyi and N. gouldi  

Microsoft Academic Search

During roosting in summer, reproductive female bats appear to use torpor less frequently and at higher body temperatures (T\\u000a b) than male bats, ostensibly to maximise offspring growth. To test whether field observations result from differences in thermal\\u000a physiology or behavioural thermoregulation during roosting, we measured the thermoregulatory response and energetics of captive\\u000a pregnant and lactating female and male long-eared

Christopher Turbill; Fritz Geiser



Adolescents' ambivalence about becoming pregnant predicts infrequent contraceptive use: A prospective analysis of nonpregnant African American females  

Microsoft Academic Search

This study prospectively investigated the hypothesis that ambivalence about becoming pregnant is associated with comparatively less frequent use of contraception. Findings from a sample of sexually active African American adolescent, nonpregnant females (n = 375) supported this hypothesis. Prevention programs may benefit from content designed to redress adolescents’ positive beliefs about early parenthood. (Am J Obstet Gynecol 2002;186:251-2.)

Richard A. Crosby; Ralph J. DiClemente; Gina M. Wingood; Susan L. Davies; Kathy Harrington




EPA Science Inventory

Phenobarbital pretreatment was found not to induce Triton X-100 activated hepatic microsomal neonatal UDP-glucuronyltransferase activity towards phenolphthalein in male, female and pregnant female rats....


Cadmium toxicity to the cornea of pregnant rats: Electron microscopy and x-ray microanalysis  

SciTech Connect

Cadmium toxicity to the cornea of pregnant rats was studied using the electron microscope and x-ray microanalyzer. In in-vivo experiments, severe corneal edema occurred in pregnant dams that received intraperitoneal injections of cadmium sulphate for 4 days during gestation, but not in nonpregnant rats. Prominent swelling of mitochondria and the occurrence of intra- and intercellular vacuoles in the corneal endothelium were observed only in pregnant dams. In in-vitro experiments, electron-dense deposits consisting of cadmium-oxine complexes were preferentially found in swollen mitochondria of the endothelial cells. Cadmium peaks were obtained from these deposits with x-ray microanalysis. These data suggest that the corneal edema observed after administration of cadmium may imply the disturbance of pump function and barrier function of the corneal endothelium due to the primary toxic effects of this metal on mitochondria.

Yoshizuka, M.; McCarthy, K.J.; Kaye, G.I.; Fujimoto, S. (Univ. of Occupational and Environmental Health, School of Medicine, Kitakyushu (Japan))



Oral exposure to cylindrospermopsin in pregnant rats: reproduction and foetal toxicity studies.  


Cylindrospermopsin (CYN) induces toxicity in pregnant mice when administered intraperitoneally. This study investigated whether oral exposure to CYN (0.03, 0.3 and 3 ?g/kg) during pregnancy causes toxic effects and impairs gestation in rats. The results of reproductive performance and teratology studies were similar between the control and experimental dams. Our findings suggest that CYN consumption within the guideline values for drinking water is not able to promote foetal toxicity or alterations in rat reproductive performance. PMID:23988391

Sibaldo de Almeida, Cristhiano; Costa de Arruda, Andrea Caroline; Caldas de Queiroz, Erika; Matias de Lima Costa, Haline Tereza; Barbosa, Patrícia Fernandes; Araújo Moura Lemos, Telma Maria; Oliveira, Cláudia Nunes; Pinto, Ernani; Schwarz, Aline; Kujbida, Paula



Acute hypoxia during organogenesis affects cardiac autonomic balance in pregnant rats.  


Changes in ECG parameters were studied in pregnant rats exposed to acute hypobaric hypoxia during the period of organogenesis (gestation days 9 to 10). Rats with low, medium, and high tolerance to hypoxia exhibited pronounced autonomic nervous system imbalance, which become apparent as a loss of correlation between various parameters of ECG signals recorded at rest and during exposure to some stress factors existing under normal conditions. PMID:16027800

Maslova, M V; Graf, A V; Maklakova, A S; Krushinskaya, Ya V; Sokolova, N A; Koshelev, V B



Accelerated Maturation of the Thymic Stroma in the Progeny of Adrenalectomized Pregnant Rats  

Microsoft Academic Search

The possible role played by glucocorticoids (GCs) in the development of thymic stromal cell components has been studied in the progeny of adrenalectomized pregnant rats (FAdx), an experimental model which ensures the absence of GCs until the establishment of the fetal hypothalamus-pituitary gland-adrenal gland axis. As previously demonstrated for thymocytes, the lack of GCs early in ontogeny results in an

Rosa Sacedón; Alberto Varas; Eva Jiménez; Juan José Múñoz; Angeles Vicente; Agustín G. Zapata




EPA Science Inventory

Trichloroacetonitrile (TCAN) is a by-product of the chlorine disinfection of water containing natural organic material. When administered by gavage to pregnant Long-Evans rats in a medium-chain triglyceride vehicle, tricaprylin oil (Tricap), at a volume of 10 ml/kg, TCAN induced ...


Tumor growth influences skeletal muscle protein turnover in the pregnant rat.  


The implantation of a fast growing tumor (the Yoshida AH-130 ascites hepatoma) to mid-pregnant rats resulted in no changes in fetus weight, in spite of an important body weight decrease observed in the mother. Tumor-bearing pregnant rats showed an accelerated muscle protein degradation that resulted in decreases in both gastrocnemius and soleus muscle weight and protein content. Although very slight changes were observed in liver protein turnover after tumor implantation, muscle protein degradation and ubiquitin gene expression were increased (in relation with the non-tumor-bearing pregnant rats) in the first postimplantation period (0-4 d), whereas it remained lower in the second studied period (4-7 d), compensating for the initial differences when the whole period (0-7 d) was considered. Similar results were observed when muscle protein synthesis was studied. On the whole, tumor growth resulted in a slightly decreased protein accumulation rate. The results presented suggest that the implantation of this tumor in the pregnant rat has little or no consequences in fetal growth but results in an important muscle waste in the mother. PMID:9475293

Carbó, N; Costelli, P; López-Soriano, F J; Argilés, J M




EPA Science Inventory

EFFECTS OF BROMODICHLOROMETHANE (BDCM) ON EX VIVO LUTEAL FUNCTION IN THE PREGNANT F344 RAT. S. R. Bielmeier1, A. S. Murr2, D. S. Best2, J. M. Goldman2, and M. G. Narotsky2 1 Curriculum in Toxicology, Univ. of North Carolina, Chapel Hill, NC, USA 2 Reproductive T...


Time of birth and daily activity mediated by feeding rhythms in the pregnant rat  

E-print Network

Time of birth and daily activity mediated by feeding rhythms in the pregnant rat M. J. BOSC, Agnès, France. Summary. The temporal relationship between time of birth and daily physical activity has been for three hours per day from 2, 9, 14 and 21 h, respectively. In groups 9PF and 14PF, births were clustered

Boyer, Edmond


Investigation on the role of Spirulina platensis in ameliorating behavioural changes, thyroid dysfunction and oxidative stress in offspring of pregnant rats exposed to fluoride.  


The study investigated the role of Spirulina platensis in reversing sodium fluoride-induced thyroid, neurodevelopment and oxidative alterations in offspring of pregnant rats. The total antioxidant activity, phycocyanins, and ? carotene content were quantified in Spirulina. Thirty female pregnant rats were allocated to six groups and treatment initiated orally from embryonic day (ED) 6 to postnatal day (PND) 15. Treatment groups included control, Spirulina alone, sodium fluoride (20 mg/kg) alone, and sodium fluoride along with Spirulina (250 and 500 mg/kg). Serum fluoride levels were determined on ED 20 and PND 11. Offspring were subjected to behavioural testing, estimation of thyroid levels, oxidative measurements in brain mitochondrial fraction and histological evaluation of the cerebellum. Fluoride-induced alterations in thyroid hormones, behaviour and increased oxidative stress. Spirulina augmented the displacement of fluoride, facilitated antioxidant formation, improved behaviour and protected Purkinje cells. Supplementing Spirulina during pregnancy could reduce the risk of fluoride toxicity in offspring. PMID:23578649

Banji, David; Banji, Otilia J F; Pratusha, N Gouri; Annamalai, A R



Protective effects of Allium sativum against defects of hypercholesterolemia on pregnant rats and their offspring.  


Sixty fertile female and male albino rats of Wistar strain (I male/ 3 females) were used in the present study. The females were divided into four groups of ten rats each. Group 1 received water and standard feeds for thirty-four days. Group 2 was fed with a cholesterol-containing diet (1%) for two weeks prior to onset of gestation and maintained administration till parturition, produce atherosclerosis (34 days). Group 3 received intragastric administration of 100mg homogenate of garlic (Allium sativum)/kg body weight for three weeks prior to onset of gestation as well as throughout the gestation period. Group 4 intragastrically administered garlic for one week of group B and maintained with combined garlic-treatment for the mentioned period. At parturition, the pregnant were sacrificed and serum total cholesterol (TCL), triglycerides (TG), HDL, LDL and creatine kinase activity (CK) were determined. The total numbers of offspring were recorded and examined morphological for congenital abnormalities. Biopsies of heart and dorsal aorta of both pregnant and their offspring (1 day-age) were processed for investigation at light and transmission electron microscopy. The skeleton of the newborn of different experimental groups were stained with alizarin red s and mor-phometric assessment of mandibular and appendicular bone length. The study revealed that the myocardium of atherosclerotic mother exhibited leuhkocytic inflammatory cell infiltration associated with necrosis, eosinophilia of myocardiai fibers, and edema of blood vessels. Ultrastructural studies revealed swelling of mitochondria, disruption of cristae in the myocardiai muscle fibers. The dorsal aorta possessed accumulation of extra-cellular lipid in intima lining of endothelium. The collagenous fibrils in the tunica adventitia became fragile and loosely separated from each other. Numerous foamy lipid loaden cells were detected within the tunica intima causing deterioration of the elastic fibers, resulting in fibrinoid necrosis. Oral supplementation with Allium sativum (100 mg/ kg) ameliorated these effects in myocardium muscle of mothers and offspring; however the dorsal aorta of mothers showed partial amelioration. Hypercholesterolemic mothers exhibited marked alterations in serum TCL, TG, LDL and CK activity. Supplementation with Allium sativum ameliorated the drastic biochemical alterations. Concerning pregnancy, hypercholesterolemia increased the incidence of abortion and abnormalities of the newborn including decreased body weight, reduced ossification of axial (mandible) and appendicular bones. All these effects were markedly ameliorated by supplementation with Allium sativum. The author finally concluded that hypercholesterolemia exhibits pathological alterations of myocardiai muscles reducing its optimal capacity for pumping blood to different body organs along with atherosclerosis of dorsal aorta which intern affect the progress of gestation and development of both morphological and skeletal abnormalities. Allium sativum-supplementation leads to amelioration of both mother and their offspring investigated parameters as a result of its antioxidant activity. PMID:20607041

El-Sayyad, Hassan I; Abou-El-Naga, Amoura M; Gadallah, Abdelalim A; Bakr, Iman H



Protective effects of Allium sativum against defects of hypercholesterolemia on pregnant rats and their offspring  

PubMed Central

Sixty fertile female and male albino rats of Wistar strain (I male/ 3 females) were used in the present study. The females were divided into four groups of ten rats each. Group 1 received water and standard feeds for thirty-four days. Group 2 was fed with a cholesterol-containing diet (1%) for two weeks prior to onset of gestation and maintained administration till parturition, produce atherosclerosis (34 days). Group 3 received intragastric administration of 100mg homogenate of garlic (Allium sativum)/kg body weight for three weeks prior to onset of gestation as well as throughout the gestation period. Group 4 intragastrically administered garlic for one week of group B and maintained with combined garlic-treatment for the mentioned period. At parturition, the pregnant were sacrificed and serum total cholesterol (TCL), triglycerides (TG), HDL, LDL and creatine kinase activity (CK) were determined. The total numbers of offspring were recorded and examined morphological for congenital abnormalities. Biopsies of heart and dorsal aorta of both pregnant and their offspring (1 day-age) were processed for investigation at light and transmission electron microscopy. The skeleton of the newborn of different experimental groups were stained with alizarin red s and mor-phometric assessment of mandibular and appendicular bone length. The study revealed that the myocardium of atherosclerotic mother exhibited leuhkocytic inflammatory cell infiltration associated with necrosis, eosinophilia of myocardiai fibers, and edema of blood vessels. Ultrastructural studies revealed swelling of mitochondria, disruption of cristae in the myocardiai muscle fibers. The dorsal aorta possessed accumulation of extra-cellular lipid in intima lining of endothelium. The collagenous fibrils in the tunica adventitia became fragile and loosely separated from each other. Numerous foamy lipid loaden cells were detected within the tunica intima causing deterioration of the elastic fibers, resulting in fibrinoid necrosis. Oral supplementation with Allium sativum (100 mg/ kg) ameliorated these effects in myocardium muscle of mothers and offspring; however the dorsal aorta of mothers showed partial amelioration. Hypercholesterolemic mothers exhibited marked alterations in serum TCL, TG, LDL and CK activity. Supplementation with Allium sativum ameliorated the drastic biochemical alterations. Concerning pregnancy, hypercholesterolemia increased the incidence of abortion and abnormalities of the newborn including decreased body weight, reduced ossification of axial (mandible) and appendicular bones. All these effects were markedly ameliorated by supplementation with Allium sativum. The author finally concluded that hypercholesterolemia exhibits pathological alterations of myocardiai muscles reducing its optimal capacity for pumping blood to different body organs along with atherosclerosis of dorsal aorta which intern affect the progress of gestation and development of both morphological and skeletal abnormalities. Allium sativum-supplementation leads to amelioration of both mother and their offspring investigated parameters as a result of its antioxidant activity. PMID:20607041

El-Sayyad, Hassan I; Abou-El-Naga, Amoura M; Gadallah, Abdelalim A; Bakr, Iman H



Structural and functional reserve of steroidogenic membranes in stimulated luteal cells of pregnant rats.  


A comparison was made of the ultrastructural features of the remaining corpora lutea (CL) of five unilaterally ovariectomised and five control pregnant rats. Unilateral ovariectomy (ULO) was carried out on Day 8 of gestation; this treatment has been shown to double the normal rate of progesterone secretion by the remaining ovary within 8 days. On Day 16, the ovaries from both ULO and control rats were examined stereologically. The mass of luteal tissue remaining in ULO rats was only 44% of that in the controls, but their plasma progesterone concentration was 81% and not significantly different from the control value. The CL were 10% heavier in ULO rats and the amount of luteal cell cytoplasm per CL was 21% greater. The percentage of the CL occupied by luteal cells was 15% greater in ULO rats but the interstitial space was 50% less. There was no significant change in the percentage of the luteal cell cytoplasm occupied by cytosol, agranular endoplasmic reticulum (AER), mitochondria and electron-dense granules. The surface area per unit cytoplasmic volume of AER and outer and inner mitochondrial membranes (OMM and IMM, respectively) was not affected. However, expressed per CL, both the AER and IMM membrane surface areas were increased by around 30%. These morphometric changes would only account for about 30% of the reported increase in hormone secretion by the CL of ULO rats, and they suggest that the CL of Day 16 pregnant rats may have reached their optimal structural condition. PMID:1769896

Meyer, G T; Bruce, N W



Metabonomic and metallomic profiling in the amniotic fluid of malnourished pregnant rats.  


Epidemiology and studies in animal models have revealed that prenatal malnutrition is highly correlated with abnormal fetal neurodevelopment. We present here a combined metabonomic and metallomic profiling technique to associate the metabolic and trace-elemental composition variations of rat amniotic fluid (AF) in malnourished pregnant rats with the retardation of fetal rat neurodevelopment. The AF samples from three groups of pregnant Sprague-Dawley rats, which were fed either a normal diet, a low-protein diet, or "a famine diet", were subjected to GC/MS and ICP/MS combined with multivariate data analysis (MVDA). PCA scores plot of both GC/MS and ICP/MS data showed similar and unique metabolic signatures of AF in response to the different diets. Rats in the famine group released increased amounts of glycine, inositol, putrescine, and rubidium and decreased amounts of methionine, dopa, tryptophan, glutamine, zinc, cobalt, and selenium in the AF. These discriminable variations in the AF may indicate the abnormality of a number of metabolic pathways in fetal rats including the folate cycle and methionine pathway, the monoamine pathway, and tri-iodothyronine (T3) metabolism. The abnormalities may be the result of metabolites or elemental differences or a combination of both. This study demonstrates the potential of combining profiling of small-molecule metabolites and trace elements to broaden the understanding of biological variations associated with fetal neurodevelopment induced by environmental perturbation. PMID:18348512

Shen, Qing; Li, Xin; Qiu, Yunping; Su, Mingming; Liu, Yumin; Li, Houkai; Wang, Xiaoyan; Zou, Xiangyu; Yan, Chonghuai; Yu, Lan; Li, Sheng; Wan, Chunling; He, Lin; Jia, Wei



Female ultrasonic vocalizations have no incentive value for male rats.  


Ultrasonic vocalizations (USVs) are emitted in response to a sexual partner before, during, and after copulation. These vocalizations are the so-called 50-kHz USVs and can be subdivided into flat and frequency-modulated (FM) 50-kHz trill calls. In the present series of experiments, the potential unconditioned and conditioned incentive properties of female 50-kHz USVs for male rats were examined. USVs were recorded from sexually receptive females during the precopulatory phase. A complete 10-min song, or single flat or FM trill calls were selected as auditory stimuli for Experiments 1 and 2. As FM trill calls, a multistep call was used in Experiments 1 and 2a, and an upward ramp call was used in Experiment 2b. The auditory stimuli were played back with a loudspeaker to naïve and sexually experienced male rats in a sexual incentive motivation test. The odor of a sexually receptive female rat was also used as an incentive stimulus for comparison. In a third experiment, a devocalized female, a sham female and a male rat were used as incentive stimuli. It was found that the auditory stimuli did not induce approach behavior in naïve and sexually experienced male rats, but the olfactory stimulus did. In addition, the males spent equal amounts of time in the vicinity of devocalized and vocalizing females. These data show that 50-kHz USVs neither are unconditioned nor conditioned incentives for male rats. PMID:23458403

Snoeren, Eelke M S; Ågmo, Anders



Prostaglandin F receptor expression in intrauterine tissues of pregnant rats  

PubMed Central

In this investigation, we studied the expression and localization of rat prostaglandin F (FP) receptor in uterine tissues of rats on gestational Days 10, 15, 18, 20, 21, 21.5 and postpartal Days 1 and 3 using Western blotting analysis, real-time PCR, and immunohistochemistry. A high level of immunoreactivity was observed on gestational Days 20, 21, and 21.5 with the most significant signals found on Day 20. FP receptor protein was expressed starting on gestational Day 15, and a fluctuating unsteady increase was observed until delivery. Uterine FP receptor mRNA levels were low between Days 10 and 18 of gestation (p < 0.05). The transcript level increased significantly on Day 20 and peaked on Day 21.5 just before labor (p < 0.05). There was a positive correlation between FP receptor mRNA expression and serum estradiol levels (rs = 0.78; p < 0.01) along with serum estradiol/progesterone ratios (rs = 0.79; p < 0.01). In summary, we observed an increase FP receptor expression in rat uterus with advancing gestation, a marked elevation of expression at term, and a concominant decrease during the postpartum period. These findings indicate a role for uterine FP receptors in the mediation of uterine contractility at term. PMID:24136214

Kanca, Halit; Yar, Atiye Seda; Helvacio?lu, Fatma; Menev?e, Sevda; Çalgüner, Engin; Erdo?an, Deniz



Mixtures of environmentally relevant endocrine disrupting chemicals affect mammary gland development in female and male rats.  


Estrogenic chemicals are able to alter mammary gland development in female rodents, but little is known on the effects of anti-androgens and mixtures of endocrine disrupting chemicals (EDCs) with dissimilar modes of action. Pregnant rat dams were exposed during gestation and lactation to mixtures of environmentally relevant EDCs with estrogenic, anti-androgenic or dissimilar modes of action (TotalMix) of 100-, 200- or 450-fold high end human intake estimates. Mammary glands of prepubertal and adult female and male offspring were examined. Oestrogens increased mammary outgrowth in prepubertal females and the mRNA level of matrix metalloproteinase-3, which may be a potential biomarker for increased outgrowth. Mixtures of EDCs gave rise to ductal hyperplasia in adult males. Adult female mammary glands of the TotalMix group showed morphological changes possibly reflecting increased prolactin levels. In conclusion both estrogenic and anti-androgenic chemicals given during foetal life and lactation affected mammary glands in the offspring. PMID:25305543

Mandrup, Karen Riiber; Johansson, Hanna Katarina Lilith; Boberg, Julie; Pedersen, Anne Stilling; Mortensen, Mette Sidsel; Jørgensen, Jennifer Solgaard; Vinggaard, Anne Marie; Hass, Ulla



Estrogen Abolishes Latent Inhibition in Ovariectomized Female Rats  

ERIC Educational Resources Information Center

Estrogen is frequently prescribed as a method of birth control and as hormone replacement therapy for post-menopausal women with varied effects on cognition. Here the effects of estrogen on attention were examined using the latent inhibition (LI) behavioral paradigm. Ovariectomized (OVX) female rats were given either estrogen benzoate (EB, 10 or…

Nofrey, Barbara S.; Ben-Shahar, Osnat M.; Brake, Wayne G.



Oxytocin Induces Maternal Behavior in Virgin Female Rats  

Microsoft Academic Search

Intracerebroventricular administration of oxytocin to virgin female rats that had been ovariectomized and primed with estrogen 48 hours previously induced a rapid onset of full maternal behavior. The maternal behavior persisted and its incidence was dose-related. Tocinoic acid, the ring structure of oxytocin, also rapidly induced the onset of persistent, full maternal behavior. Arginine vasopressin induced persistent maternal behavior, but

Cort A. Pedersen; John A. Ascher; Yvonne L. Monroe; Arthur J. Prange




EPA Science Inventory

During chronic treatment of weanling female rats with daily injections (0.069 mmol/kg of gamma-hexachlorocyclohexane (lindane, gamma-HCH), the treatment induced a significant 20% increase in body weight after 110 days. Further investigation with 0, 5, 10, 20 and 40 mg/kg lindane ...


Tumorigenic effects of dichloroacetic acid in female F344 rats  

EPA Science Inventory

Introduction: Dichloroacetic acid (DCA) is a halogenated organic acid produced during oxidant disinfection of drinking water. Prior studies indicate that DCA may increase liver tumors in mice. Here we evaluated the hepatic tumorigenicity of DCA in female rats when given alone ...


3. Impact of altered gravity on CNS development and behavior in male and female rats  

NASA Astrophysics Data System (ADS)

The present study examined the effect of altered gravity on CNS development. Specifically, we compared neurodevelopment, behavior, cerebellar structure and protein expression in rat neonates exposed perinatally to hypergravity. Pregnant Sprague-Dawley rats were exposed to 1.5G-1.75G hypergravity on a 24-ft centrifuge starting on gestational day (G) 10, through giving birth on G22/G23, and nursing their offspring through postnatal day (P) 21. Cerebellar mass on P6 was decreased in 1.75G-exposed male pups by 27.5 percent; in 1.75G-exposed female pups it was decreased by 22.5 percent. The observed cerebellar changes were associated with alterations in neurodevelopment and motor behavior. Exposure to hypergravity impaired performance on the following neurocognitive tests: (1) righting time on P3 was more than doubled in 1.75G-exposed rats and the effect appeared more pronounced in female pups, (2) startle response on P10 was delayed in both male and female HG pups; HG pups were one-fifth as likely to respond to a clapping noise as SC pups, and (3) performance on a rotorod on P21 was decreased in HG pups; the duration of the stay on rotorod recorded for HG pups of both sexes was one tenth of the SC pups. Furthermore, Western blot analysis of selected cerebellar proteins suggested gender-specific changes in glial and neuronal proteins. On P6, GFAP expression was decreased by 59.2 percent in HG males, while no significant decrease was observed in female cerebella. Synaptophysin expression was decreased in HG male neonates by 29.9 percent and in HG female neonates by 20.7 percent as compared to its expression in SC cerebella. The results of this experiment suggest that perinatal exposure to hypergravity affects cerebellar development and behavior differently in male and female neonates. If one accepts that hypergravity is a good paradigm to study the effect of microgravity on the CNS, and since males and females were shown to respond differently to hypergravity, it can be surmised that males and females may respond differently to the microgravity encountered in space. Supported by NIEHS grant ES11946-01 awarded to E. S-S.

Sajdel-Sulkowska, E. M.; Nguon, K.; Ladd, B.; Sulkowski, V. A.; Sulkowski, Z. L.; Baxter, M. G.


Changes in plasma progesterone in female Vipera aspis L. (Reptilia, Viperidae) during the sexual cycle in pregnant and nonpregnant females.  


The plasma progesterone concentration in female Vipera aspis changes during pregnancy and exhibits an increase before ovulation, a summer peak, a decrease up to parturition, and a new increase at the beginning of hibernation. For females in their first or second year after gestation, the evolution of plasma progesterone shows a spring peak and a summer peak. Whatever the stage of the sexual cycle, females present two annual periods of steroidogenic activity producing plasma progesterone: one in spring and one in summer. All data suggest an annual endogenous endocrinological cycle of reproduction, modulated by external factors (temperature, food availability). The origin of plasma progesterone and its control in the sexual cycle are discussed. PMID:2347489

Naulleau, G; Fleury, F



Aspects of the Development of Housing for the Spaceflight of Pregnant and Lactating Rats with Neonates  

NASA Technical Reports Server (NTRS)

Recent and upcoming spaceflights are investigating the effect of weightlessness on developing neural and organ systems. Pregnant rats and dams with neonates have to be accommodated in cages that support the special requirements of these animals. Extensive ground testing of cage concepts, the effect of launch and landing stresses on the maintenance of pregnancy and maternal behavior at different neonatal ages, and techniques for monitoring adaptability to change are discussed. A spaceflight opportunity for the NlH.R3 payload of rat families at three different postnatal ages demonstrated that the survival of very young animals was not good but that older newborns could be returned to Earth in reasonably good health. The development of cages for the Research Animal Holding Facility (RAHF) to support the flight of neonates on Neurolab was continued and incorporated modifications that were demonstrated by the NIH.R3 flight. Other modifications to the RAHF are discussed. Data from biocompatibility and experiment verification testing are presented.

Hinds, William E.; Mayer, David J.; Evans, Juli; Spratt, Shahn; Lane, Philip K.; Rodriguez, Shari L.; Navidi, Meena; Armstrong, Rachel; Lemos, Bonnie; Dalton, Bonnie P. (Technical Monitor)



Reproductive toxicity associated with acrylamide treatment in male and female rats  

SciTech Connect

The present study was designed to evaluate the influence of acrylamide (ACR) on male and female reproductive function. Male rats received ACR in drinking water (50, 100, or 200 ppm) for up to 10 wk. Copulatory behavior, semen, and (for controls and 100 ppm only) fertility and fetal outcomes were evaluated. Females received ACR (25, 50, 100 ppm) for 2 wk prior to initiation of breeding and then throughout gestation and lactation. Hindlimb splaying was apparent in the 200-ppm males by wk 4; less severe splaying appeared in the 100-ppm group at wk 8. Disruptions in copulatory behavior preceded the appearance of this ataxia. These disruptions in mating performance interfered with ejaculatory processes and subsequent transport of sperm, since semen was found in the uterus of only 1 of the 15 females mated with the 100-ppm males at wk 9. Moreover, only 33% of the females mated with the 100-ppm males were pregnant. Postimplantation loss was also significantly increased in this group. Hindlimb splaying appeared in the females receiving 100 ppm ACR during wk 1-2 of pregnancy. Body weight and fluid intake were also depressed. Dams in the 50-ppm group showed depression in these parameters during the last 2 wk of lactation. ACR did not significantly affect mating performance of the females, pregnancy rates, litter size, or survival. However, ACR did significantly depress pup body weight at birth (100-ppm group) and weight gain during lactation through postweaning, d 42 (50- and 100-ppm groups). Vaginal patency was delayed in the 100-ppm group only.

Zenick, H.; Hope, E.; Smith, M.K.



Factors influencing fluoxetine-induced sexual dysfunction in female rats  

PubMed Central

Treatment with selective serotonin reuptake inhibitors, such as fluoxetine, produces sexual side effects with low sexual desire being the most prevalent effect in females. In few studies have preclinical models for such antidepressant-induced sexual dysfunction been fruitful. In the current manuscript, the effects of fluoxetine on multiple measures of female sexual motivation and sexual receptivity were examined. Ovariectomized, Fischer rats were primed with 10 ?g estradiol benzoate and 500 ?g progesterone. Partner preference, active investigation of the male, and measures of sexual behavior were examined after injection with 15 mg/kg fluoxetine. Factors (pretesting for sexual behavior, size of the test arena, non-contact time with a male) that differ among experiments designed to study antidepressant-induced female rat sexual dysfunction were studied. The male preference ratio was not affected by fluoxetine treatment but active investigation of the male was reduced; lordosis behavior was inhibited and pretesting for sexual receptivity amplified fluoxetine's inhibition; size of the testing arena or non-contact experience with the male had no effect. Regardless of test condition, when given the opportunity to escape from the male, fluoxetine-treated females displayed escape behavior. Measures of male preference and active investigation, but not lordosis behavior, appeared to be affected by fluoxetine's impact on activity. The collective data provided a behavioral profile of fluoxetine-induced sexual dysfunction. These findings reinforce the value of multiple measures when attempting to model antidepressant-induced female sexual dysfunction. PMID:22835821

Adams, Sarah; Heckard, Danyeal; Hassell, James; Uphouse, Lynda



Clitoral anesthesia disrupts paced copulation in the female rat.  


Clitoral stimulation produced by sexual contact with a partner or during manual stimulation is associated with pleasure in humans, and produces conditioned place preference in rats. The present experiment investigated the effect of blocking genitosensory stimulation of the clitoris with lidocaine during copulation in female rats on a measure of female sexual motivation: pacing behavior. Sexually naïve, ovariectomized female rats were treated with 10?g estradiol benzoate 48h and 500?g progesterone 4h prior to a 30-min copulatory trial with a sexually vigorous stimulus male scheduled every 4days. A total of 10 copulatory sessions were divided into two phases of 5 trails each. In the first phase, females received an injection (0.05ml) of either 2% lidocaine, saline, or no injection to the clitoral sheath under isoflurane anesthesia immediately prior to the start of a copulatory session, and were then placed on one side of a paced mating chamber and allowed to copulate for 30min. In the second phase, females previously injected with lidocaine were switched to saline and vice versa, and the no injection group remained the same. Variables measured included overall time spent with the males, number of solicitations, contact-return latencies following male mounts, intromissions, and ejaculations; the frequency of entrances and exits from the male chamber, and frequency of mounts, intromissions, ejaculations. Sexual behavior was examined at session 1, session 5, and session 10. At test 5, females that received LID had a greater number of entrances/exits but spent significantly less time in the presence of the male during the copulatory bout than CNTL animals. These females also displayed a trend for longer contact return latencies s after ejaculations than VEH and CNTL groups. On session 10, females that received LID and subsequently switched to VEH treatment no longer differed from controls in entrance/exit numbers, time spent with males or ejaculation contact return latency. They did however, receive a greater number of intromissions and displayed shorter inter intromission intervals compared to CNTLs. We suggest that clitoral stimulation in the rat serves as both a reward signal and may contribute to the detection of differences in copulatory stimuli that are critical to pacing and potentially, the initiation of pregnancy. PMID:24176775

Parada, M; Sparks, L M; Censi, S; Pfaus, J G



“Pregnant and Operating”: Evaluation of a Germany-wide Survey Among Female Gynaecologists and Surgeons  

PubMed Central

The current law on the protection of expectant and nursing mothers largely rules out surgical activities during pregnancy for female doctors who perform surgical roles in hospitals. The proportion of female junior staff in gynaecology amounts to 80?%, and, for many of these women, surgical further training is not possible following official notification of an existing pregnancy. In a Germany-wide survey of female gynaecologists and surgeons using a questionnaire, it was determined to what extent female doctors worked in surgery during pregnancy, whether it led to complications in the pregnancy, when the employer was notified about the pregnancy, and what desire for change there is with regard to the law on the protection of expectant and nursing mothers. The data from 164 female doctors, of which 136 are gynaecologists and 28 surgeons, was evaluated. On average, the pregnancy was announced during the 14th week of pregnancy (WOP), and the doctor was not allowed to perform surgical activities in the 21st WOP. Female doctors in higher professional roles tended to announce the pregnancy later and ended their surgical activities later. There was no link between the time of ceasing surgical activities and an increased occurrence of complaints or complications during the pregnancy. In total, only 53?% of respondents had an appraisal during pregnancy and 75?% wanted a change in the law on the protection of expectant and nursing mothers. PMID:25278630

Knieper, C.; Ramsauer, B.; Hancke, K.; Woeckel, A.; Ismail, L.; Bühren, A.; Toth, B.



Hypothyroidism and oxidative stress: differential effect on the heart of virgin and pregnant rats.  


The present study investigates the effects of hypothyroidism on both the redox state and the thyroid hormone receptors expression in the heart ventricle of virgin and pregnant rats.Hypothyroid state was induced by 6-n-propyl-2-thiouracil in drinking water given to Wistar rats starting 8 days before mating until day 21 of pregnancy or for 30 days in virgin rats. Serum paraoxonase-1 (PON-1) activity, serum and heart nitrites, and thiobarbituric acid-reactive substances (TBARS) were analyzed. Heart protein oxidation, as carbonyls, and copper-zinc superoxide dismutase (CuZnSOD), glutathione peroxidase (GPx), and catalase (CAT) activities, were determined. In addition, heart expressions of NADPH oxidase (NOX-2), CAT, SOD, GPx, and thyroid receptors (TR? and TR?) mRNA were assessed by RT-PCR. Inducible and endothelial Nitric Oxide Synthase (iNOS and eNOS) were determined by Western blot. Hypothyroidism in the heart of virgin rats decreased TR? and TR? expressions, and induced oxidative stress, leading to a decrease of nitrites and an increase of carbonyls, NOX-2 mRNA, and GPx activity. A decreased PON-1 activity suggested low protection against oxidative stress in blood circulation. Pregnancy reduced TR? and TR? mRNA expressions and induced oxidative stress by increasing nitrite and TBARS levels, SOD and CAT activities and NOX-2, eNOS and iNOS expressions, while hypothyroidism, emphasized the decreases of TR? mRNA levels and did not alter the redox state in the heart. TR expressions and redox balance of rat hearts depend on the physiological state. Pregnancy per se seems to protect the heart against oxidative stress induced by hypothyroidism. Supporting Information for this article is available online at PMID:23921912

Carmona, Y V; Coria, M J; Oliveros, L B; Gimenez, M S



Intrauterine Pressure (IUP) Telemetry in Pregnant and Parturient Rats: Potential Applications for Spacecraft and Centrifugation Studies  

NASA Technical Reports Server (NTRS)

Rats exposed to spaceflight or centrifugation from mid-to late pregnancy undergo either more or fewer labor contractions at birth, respectively, as compared to those in normal Earth gravity (1-g). In this paper, we report the development and validation of a new telemetric method for quantifying intrauterine pressure (IUP) in freely-moving, late pregnant and parturient rats. We plan to utilize this technique for studies of labor in altered gravity, specifically, to ascertain forces of uterine during birth, which we believe may be changed in micro- and hypergravity. The technique we describe yields precise, reliable measures of the forces experienced by rat fetuses during parturition. A small, surgically-implantable telemetric pressure sensor was fitted within a fluid-filled balloon. The total volume of the sensor-balloon assembly matched that of a full term rat fetus. Real-time videorecordings of sensor-implanted rat dams and non- implanted control dams enabled us to characterize effects of the intrauterine implant on behavioral aspects of parturition. Contraction frequency, duration, pup-to-pup birth intervals and pup-oriented activities of the dams measured during the peri-birth period were unaffected by the sensor implant. These findings establish intrauterine telemetry as a reliable, non-invasive technique for quantifying intrauterine pressures associated with parturition on Earth and in altered gravity environments. This new technology, readily amenable to spaceflight and centrifugation platforms, will enable us to answer key questions regarding the role of altered labor frequency labor in the adaptation of newborn mammals to hypo- and hypergravity.

Ronca, A. E.; Baer, L. A.; Wade, C. E.



Toxopathological and cytogenetic effects of aflatoxin B1 (AFB1) on pregnant rats.  


The present study was carried out to evaluate the toxopathological effects and macro-DNA damage of Aflatoxin B1 (AFB1) in pregnant rats at a dose of 1mg/kg. body wt., given from 6th to 15th day of gestation. The effects and damage are represented by histopathological changes and different types of chromosomal aberrations in dams, in addition to teratogenic changes in the feti. Pregnant dams revealed a significant decrease in their body weights and gross enlargement of the liver. Histologically, the liver showed necrotic areas and congested central vein. The kidneys revealed interstitial hemorrhages, renal casts, degeneration and necrosis. The lungs revealed lymphocytic infiltrates in the interstitial tissue, while the spleen revealed lymphoid depletion. Chromosomal analysis revealed both structural and numerical chromosomal aberration, including centromeric attenuations, chromatid gaps, chromatid breaks, end-to-end associations, fragments, ring chromosomes, deletions, dicentric chromosomes, chromosomal fusions, centric fusions, stickness and hypoployploidy. Centromeric attenuations and end-to-end associations were more frequent than other chromosomal aberrations. Concerning the teratogenic effects in the fetuses, the toxin induced multiple skeletal anomalies. These anomalies included incomplete ossification of skull bones and failure of ossification of long and flat bones. PMID:25023881

Fetaih, Hamdy A; Dessouki, Amina A; Hassanin, Abeer A I; Tahan, Ahmed S



Congenital hydrocephalus following X-irradiation of pregnant rats on an early gestational day  

SciTech Connect

When pregnant rats were X-irradiated at a dose of 100 R on gestational day 9.5, a considerable number of postnatally-viable hydrocephalic offspring resulted, all of which were accompanied with bilateral micro- or anophthalmia. Histological studies revealed that the cerebral aqueduct of the congenital hydrocephalic brain was severely stenosed, and the subcommissural organ was reduced in size and displaced at some distance from the anterior end of the cerebral aqueduct. From embryological studies, it was considered that the maldevelopment of the subcommissural organ in the X-irradiated fetus might cause a reduction in the amount of its secretions which function as a cushion preventing complete closure of the cerebral aqueduct during fetal life, resulting in stenosis of the cerebral aqueduct.

Takeuchi, I.K.; Takeuchi, Y.K.



Female-specific hypertension loci on rat chromosome 13  

PubMed Central

A 3.7 Mb region of rat chromosome 13 (45.2–49.0 Mb) affects blood pressure (BP) in females only, indicating the presence of gender-specific BP loci in close proximity to the Renin locus. In the present study, we used a series of Dahl salt-sensitive/Mcwi (SS)-13 Brown Norway (BN) congenic rat strains to further resolve BP loci within this region. We identified 3 BP loci affecting female rats only, of which the 2 smaller loci (line9BP3 and line9BP4) were functionally characterized by sequence and expression analysis. Compared with SS, the presence of a 591 Kb region of BN chromosome 13 (line9BP3) significantly lowered BP by 21 mmHg on an 8% NaCl diet (153±7 vs 174±5 mmHg, P<0.001). Unexpectedly, the addition of 23 Kb of BN chromosome 13 (line9BP4) completely erased the female-specific BP protection on 8% NaCl diet, suggesting that BN hypertensive allele(s) reside in this region. The congenic interval of the protective line 9F strain contains 3 genes (Optc, Prelp, and Fmod) and the hypertensive line 9E contains 1 additional gene (Btg2). Sequence analysis of the 2 BP loci revealed a total of 282 intergenic variants, with no coding variants. Analysis of gene expression by RT-qPCR revealed strain- and gender-specific differences in Prelp, Fmod, and Btg2 expression, implicating these as novel candidate genes for female-specific hypertension. PMID:23817491

Hoffman, Matthew J.; Flister, Michael J.; Nunez, Lizbeth; Xiao, Bing; Greene, Andrew S.; Jacob, Howard J.; Moreno, Carol



Behavioral and Physiological Analyses of Parturition In Pregnant Rats: Insights Derived from Intrauterine Telemetry  

NASA Technical Reports Server (NTRS)

During labor and birth, fetuses are exposed to considerable physical stimulation associated with labor contractions and expulsion from the womb These forces are important for the neonates' adaptation to tile extrauterine environment. To further our understanding of the relationship between labor and postpartum outcome, we developed a novel method for measuring intrauterine pressure (IUP) in freely-moving, late pregnant and parturient rats that enables us to make precise, reliable measures of the forces experienced by rat fetuses during parturition. A small (1.25 x 4 cm) telemetric blood pressure sensor was fitted within a fluid-filled balloon, similar in size to a full term rat fetus. On Gestational day (G) 19 of the rats' 22/23 day pregnancy, each dam was anesthetized and a balloon/sensor unit surgically implanted within the uterus following removal of two fetuses. Comparisons were made between sensor-implanted dams (IMPL) and a control conditions: 1) LAP-R, laparotomy with two fetuses removed or 2) LAP-NR, laparotomy with no fetuses removed. IUP signals were sampled at 10s intervals from the IMPL dams during labor and birth. Dams in all three conditions were videorecorded enabling us to analyze the effect of the implant on behavioral expressions of parturition. Contraction frequency, duration, pup-to-pup birth intervals and pup-oriented activities of the dams measured from one hour prior to the first pup birth until the birth of the third pup were unaffected by the sensor implant. Intrauterine telemetry of freely-moving dams offers significant advantages over conventional hardwired IUP measurement techniques. These findings establish and validate intrauterine telemetry as a reliable, non-invasive technique for quantifying pressures associated with parturition.

Villareal, J.; Mallery, E.; Lynch, A.; Mills, N.; Baer, L.; Wade, C.; Ronca, A.; Dalton, Donnie (Technical Monitor)



Intrauterine growth restriction transiently delays alveolar formation and disrupts retinoic acid receptor expression in the lung of female rat pups  

PubMed Central

Background We showed that intrauterine growth restriction (IUGR) increases distal airspace wall thickness at birth (postnatal age 0; P0) in rat pups (saccular stage of lung development). However, that report did not assess whether the saccular phenotype persisted postnatally or occurred in males or females. Nor did that report identify a potential molecular pathway for the saccular phenotype at P0. We hypothesized that IUGR persistently delays alveolar formation and disrupts retinoic acid receptor (RAR) mRNA and protein levels in the lung of rat pups in postnatal age- and sex-specific manners. Methods IUGR was induced in pregnant rats by bilateral uterine artery ligation. Alveolar formation and expression of RAR?, ?, and ? were quantified at P0, P6 (alveolar stage), and P21 (postalveolarization). Results IUGR increased distal airspace wall thickness in female pups at P0 only. IUGR did not affect male pups at any age. IUGR transiently increased lung RAR? protein abundance, which inhibits alveolar formation, at P0 in female pups. Serum retinol concentration was normal at all ages. Conclusions IUGR alone is not sufficient to persistently delay postnatal alveolar formation or disrupt expression RARs. We speculate that for IUGR to delay alveolar formation postnatally, a second insult is necessary. PMID:23419538

Yang, Yan; Fitzhugh, Melanie; Metcalfe, Drew; Oman, Jake; Hale, Merica; Dong, Li; Wang, Zheng-Ming; Yu, Xing; Callaway, Christopher W.; O'Brien, Elizabeth; McKnight, Robert A.; Lane, Robert H.; Albertine, Kurt H.



Somatomotor and sensory urethral control of micturition in female rats.  


In rats, axons of external urethral sphincter (EUS) motoneurons travel through the anastomotic branch of the pudendal nerve (ABPD) and anastomotic branch of the lumbosacral trunk (ABLT) and converge in the motor branch of the sacral plexus (MBSP). The aim of the present study was to determine in female rats the contribution of these somatomotor pathways and urethral sensory innervation from the dorsal nerve of the clitoris on urinary continence and voiding. EUS electromyographic (EMG) activity during cystometry, leak point pressure (LPP), and voiding efficiency (VE) were assessed in anesthetized virgin Sprague-Dawley female rats before and after transection of the above nerve branches. Transection of the MBSP eliminated EUS EMG, decreased LPP by 50%, and significantly reduced bladder contraction duration, peak pressure, intercontraction interval, and VE. Transection of the ABPD or ABLT decreased EUS EMG discharge and LPP by 25% but did not affect VE. Transection of the dorsal nerve of the clitoris did not affect LPP but reduced contraction duration, peak pressure, intercontraction interval, and VE. We conclude that somatomotor control of micturition is provided by the MBSP with axons travelling through the ABPD and ABLT. Partial somatomotor urethral denervation induces mild urinary incontinence, whereas partial afferent denervation induces voiding dysfunction. ABPD and ABLT pathways could represent a safeguard ensuring innervation to the EUS in case of upper nerve damage. Detailed knowledge of neuroanatomy and functional innervation of the urethra will enable more accurate animal models of neural development, disease, and dysfunction in the future. PMID:25339694

Cruz, Yolanda; Pastelín, César; Balog, Brian M; Zaszczurynski, Paul J; Damaser, Margot S



The effect of exposure to hypergravity on pregnant rat dams, pregnancy outcome and early neonatal development  

NASA Astrophysics Data System (ADS)

We previously reported that hypergravity exposure affects food intake and mass gain during pregnancy. In the present study, we explored the hypothesis that changes in maternal body mass in hypergravity-exposed pregnant rat dams affect pregnancy outcome and early offspring development. Furthermore, we hypothesized that the changes observed at 1.5G will be magnified at higher gravity and by exposure during critical developmental periods. To test this hypothesis, we compared maternal body mass gain, food consumption, birth outcome and early offspring development between Sprague Dawley rat dams exposed to graded (1.5 1.75G) chronic hypergravity (HG) or rotation (rotational control, RC) on a 24-ft centrifuge for 22.5 h starting on gestational day (G) 10 with dams housed under identical conditions but not exposed to hypergravity (SC). We also compared maternal body mass, food consumption, birth outcome and early offspring development between rat dams exposed to 1.65G during different stages of pregnancy and nursing. Exposure to hypergravity resulted in transient loss in body mass and prolonged decrease in food consumption in HG dams, but the changes observed at 1.5G were not magnified at 1.65G or 1.75G. On the other hand RC dams gained more mass and consumed more food than SC dams. Exposure to hypergravity also affected pregnancy outcome as evidenced by decreased litter size, lowered neonatal mass at birth, and higher neonatal mortality; pregnancy outcome was not affected in RC dams. Neonatal changes evidenced by impaired righting response observed at 1.5G was magnified at higher gravity and was dependent on the period of hypergravity exposure. On the other hand, righting response was improved in RC neonates. Hypergravity exposure during early postpartum affected the food consumption of nursing mothers and affected early survival of their offspring. The changes observed in dams and neonates appear to be due to hypergravity exposure since animals exposed to the rotation during the same period are not affected. This study suggests that while pregnancy can proceed under altered gravity, exposure to hypergravity affects pregnant dams, pregnancy outcome and the developing fetus as well as nursing dams and neonates and raises an important question whether the mammalian system possess a gravisensing ability.

Ladd, B.; Nguon, K.; Sajdel-Sulkowska, E. M.



Disposition of orally administered 2,2-Bis(4-hydroxyphenyl)propane (Bisphenol A) in pregnant rats and the placental transfer to fetuses.  

PubMed Central

We studied the disposition of bisphenol A (BPA) in pregnant female F344/DuCrj(Fischer) rats and its placental transfer to fetuses after a single oral administration of 1 g/kg BPA dissolved in propylene glycol. BPA in maternal blood, liver, and kidney reached maximal concentrations (14.7, 171, and 36 microg/g) 20 min after the administration and gradually decreased. The levels were 2-5% of the maximum 6 hr after the administration. The maximal concentration of BPA in fetuses (9 microg/g) was also attained 20 min after the administration. BPA levels then gradually reduced in a similar manner to maternal blood. These results suggest that the absorption and distribution of BPA in maternal organs and fetuses are extremely rapid and that the placenta does not act as a barrier to BPA. PMID:11049811

Takahashi, O; Oishi, S



Release of Zn from maternal tissues in pregnant rats deficient in Zn or Zn and Ca  

SciTech Connect

Earlier studies have shown that diets that increase tissue catabolism reduce the teratogenic effects of Zn deficiency. The hypothesis that Zn may be released from body tissues when the metabolic state is altered was further tested. Nonpregnant Sprague Dawley females were injected with Zn-65; after equilibration, the two major pools of Zn, bone and muscle, had different specific activities (SA), muscle being much higher. Females were mated and fed diets adequate in Zn and Ca (C) or deficient in Zn (ZnD) or deficient in both Zn and Ca (ZnCaD). Calculations using weight loss in ZnD and ZnCaD rats, Zn content of maternal bone and muscle, and total fetal Zn at term indicated that in ZnCaD rats a relatively small amount of Zn from bone early in pregnancy was sufficient to prevent abnormal organogenesis, but most fetal Zn came from breakdown of maternal muscle in the last 3 days of pregnancy. Isotope data supported this conclusion. SA of Zn in ZnD fetuses was equal and high, indicating that most Zn came from the same maternal tissue. High muscle SA prior to mating, and increased SA in tibia and liver during pregnancy suggest that muscle provided Zn for other maternal tissues as well as fetuses. In contrast, SA in C fetuses was less than 30% of that of the D groups, consistent with the earlier hypothesis that most fetal Zn in C rats is accrued directly from the diet.

Hurley, L.S.; Masters, D.G.; Lonnerdal, B.; Keen, C.L.



Chemical analysis and transplacental transfer of oseltamivir and oseltamivir carboxylic acid in pregnant rats.  


In view of the limited information on the pharmacokinetics of oseltamivir (OSE) during pregnancy, this study aims to evaluate the placental transportation of OSE and its active metabolite oseltamivir carboxylic acid (OCA) in rats. A validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) system coupled to an in vivo transplacental model has been developed to determine OSE and OCA in the placenta, amniotic fluids and fetus of 13-day pregnant Sprague-Dawley rats. Concentrations of OSE and OCA in plasma, amniotic fluids, placenta, and fetus were measured by the validated LC-MS/MS after OSE administration (10 mg/kg, i.v.). The pharmacokinetic data of both analytes were examined by non-compartmental modeling. The area under the concentration-time curve (AUC) of OCA in maternal plasma was found to be 3.6 times larger than that of OSE. The AUCs of OCA in both amniotic fluid and fetus were significantly decreased, in comparison with that in maternal plasma (reduced by 76.7 and 98.1%, respectively). We found that both OSE and OCA can penetrate the placenta, amniotic fluids and fetus in rats during pregnancy; however, the penetration of OCA was much lower than that of OSE. The mother-to-fetus transfer ratio was defined as AUC(fetus)/AUC(mother). The data demonstrated that the mother-to-fetus transfer ratio of OSE and OCA were 1.64 and 0.019, respectively, suggesting that OSE, but not OCA, penetrated through the placenta. Moreover, OCA might not be easily metabolized in the fetus due to the lack of carboxylase in the fetus. PMID:23056234

Lin, Chia-Chun; Yen, Jiin-Cherng; Wu, Yu-Tse; Lin, Lie-Chwen; Tsai, Tung-Hu



Chemical Analysis and Transplacental Transfer of Oseltamivir and Oseltamivir Carboxylic Acid in Pregnant Rats  

PubMed Central

In view of the limited information on the pharmacokinetics of oseltamivir (OSE) during pregnancy, this study aims to evaluate the placental transportation of OSE and its active metabolite oseltamivir carboxylic acid (OCA) in rats. A validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) system coupled to an in vivo transplacental model has been developed to determine OSE and OCA in the placenta, amniotic fluids and fetus of 13-day pregnant Sprague-Dawley rats. Concentrations of OSE and OCA in plasma, amniotic fluids, placenta, and fetus were measured by the validated LC-MS/MS after OSE administration (10 mg/kg, iv). The pharmacokinetic data of both analytes were examined by non-compartmental modeling. The area under the concentration-time curve (AUC) of OCA in maternal plasma was found to be 3.6 times larger than that of OSE. The AUCs of OCA in both amniotic fluid and fetus were significantly decreased, in comparison with that in maternal plasma (reduced by 76.7 and 98.1%, respectively). We found that both OSE and OCA can penetrate the placenta, amniotic fluids and fetus in rats during pregnancy; however, the penetration of OCA was much lower than that of OSE. The mother-to-fetus transfer ratio was defined as AUCfetus/AUCmother. The data demonstrated that the mother-to-fetus transfer ratio of OSE and OCA were 1.64 and 0.019, respectively, suggesting that OSE, but not OCA, penetrated through the placenta. Moreover, OCA might not be easily metabolized in the fetus due to the lack of carboxylase in the fetus. PMID:23056234

Lin, Chia-Chun; Yen, Jiin-Cherng; Wu, Yu-Tse; Lin, Lie-Chwen; Tsai, Tung-Hu



Toxicological evaluation and metal bioavailability in pregnant rats following exposure to clay minerals in the diet.  


Silicate clays are frequently added to animal feeds to bind and reduce the bioavailability of mycotoxins in the gastrointestinal tract. However, the bioavailability of trace metals in these clay feed additives has not been thoroughly investigated. Clays that act nonselectively may interact with nutrients, minerals, and other feedborne chemicals to pose significant hidden risks. In this study, a calcium montmorillonite clay (Novasil Plus, NSP) commonly used as an enterosorbent for aflatoxins and a sodium montmorillonite clay (Swy-2) (Source Clay Minerals Repository, Columbia, MO) were examined. Clays were supplemented in the balanced diet of Sprague-Dawley rats during pregnancy at a level of 2% (w/w). Evaluations of toxicity were performed on gestation d 16 and included maternal body weights, maternal feed intakes, litter weights, and embryonic resorptions. Liver, kidneys, tibia, brain, uterus, pooled placentas, and pooled embryonic mass were collected and weighed. Tissues were lyophilized and neutron activation analysis (NAA) was performed. Elements considered by NAA included Al, Ba, Br, Ca, Ce, Co, Cr, Cs, Cu, Dy, Eu, Fe, Hf, K, La, Lu, Mg, Mn, Na, Nd, Ni, Rb, S, Sb, Sc, Se, Sm, Sr, Ta, Tb, Te, Th, Ti, Tl, U, V, Yb, Zn, and Zr. Inductively coupled plasma-mass spectroscopy further confirmed that Al was below detection limits (<0.5 ppm) in the brain. Animals supplemented with either NSP or Swy-2 were similar to controls with respect to toxicity evaluations and metal analysis, with the exception of decreased brain Rb following clay supplementation. Overall, the results of this study suggest that neither NSP nor Swy-2, at relatively high dietary concentrations, influences mineral uptake or utilization in the pregnant rat. PMID:15205041

Wiles, Melinda; Huebner, Henry; Afriyie-Gyawu, Evans; Taylor, Robert; Bratton, Gerald; Phillips, Timothy



Effects of kinin blockade on the blood pressure of salt-loaded pregnant rats.  


We evaluated whether chronic inhibition of bradykinin B2 receptors by the long-acting antagonist D-Arg, [Hyp3, Thi5,D-Tic7,Oic8]-bradykinin (Hoe 140) affects blood pressure of salt-loaded pregnant rats. Pairs of rats fed a high sodium diet (0.84 mmol sodium per gram chow) were mated at 14 weeks of age. Infusion of vehicle or Hoe 140 (300 nmol/d per kilogram body weight) was performed throughout each dam's pregnancy by use of an Alzet osmotic pump implanted in the abdominal cavity. In both groups, no significant change in systolic pressure (tail-cuff plethysmography) or renal blood flow (Doppler flow-meter) was observed from that in the unmated state to that at midterm pregnancy. In the control group, systolic pressure decreased at the 21st day of pregnancy (from 126 +/- 2 to 97 +/- 2 mm Hg, P < .01), and renal blood flow increased (from 6.1 +/- 0.1 to 7.5 +/- 0.2 kHz, P < .01). These changes were nullified by the administration of Hoe 140 (systolic pressure changing from 124 +/- 2 to 118 +/- 4 mm Hg, P = NS; renal blood flow changing from 6.3 +/- 0.2 to 6.2 +/- 0.1 kHz, P = NS). In the group given Hoe 140, placental weight was greater (0.50 +/- 0.01 versus 0.43 +/- 0.01 g in controls, P < .01) and the fetal/placental weight ratio was reduced (4.53 +/- 0.09 versus 5.31 +/- 0.17 in controls, P < .01).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7721438

Madeddu, P; Parpaglia, P P; Demontis, M P; Varoni, M V; Fattaccio, M C; Anania, V; Glorioso, N



Clinostat rotation induces apoptosis in luteal cells of the pregnant rat  

NASA Technical Reports Server (NTRS)

Recent studies have shown that microgravity induces changes at the cellular level, including apoptosis. However, it is unknown whether microgravity affects luteal cell function. This study was performed to assess whether microgravity conditions generated by clinostat rotation induce apoptosis and affect steroidogenesis by luteal cells. Luteal cells isolated from the corpora lutea of Day 8 pregnant rats were placed in equal numbers in slide flasks (chamber slides). One slide flask was placed in the clinostat and the other served as a stationary control. At 48 h in the clinostat, whereas the levels of progesterone and total cellular protein decreased, the number of shrunken cells increased. To determine whether apoptosis occurred in shrunken cells, Comet and TUNEL assays were performed. At 48 h, the percentage of apoptotic cells in the clinostat increased compared with that in the control. To investigate how the microgravity conditions induce apoptosis, the active mitochondria in luteal cells were detected with JC-1 dye. Cells in the control consisted of many active mitochondria, which were evenly distributed throughout the cell. In contrast, cells in the clinostat displayed fewer active mitochondria, which were distributed either to the outer edge of the cell or around the nucleus. These results suggest that mitochondrial dysfunction induced by clinostat rotation could lead to apoptosis in luteal cells and suppression of progesterone production.

Yang, Hyunwon; Bhat, Ganapathy K.; Sridaran, Rajagopala



Re-Adaptation to 1-G of Pregnant Rats Following Exposure to Spaceflight or Centrifugation  

NASA Technical Reports Server (NTRS)

Late-pregnant rat dams were flown on a 9-day Space Shuttle mission or exposed to 1.5, 1.75 or 2-g centrifugation and compared with 1 .O-g vivarium controls. Exposure to altered gravity began on the 11th day and recovery occurred on the 20th day of the dams' 22-day pregnancy. In the 1 st experiment, comparisons were made between Flight (FLT), Synchronous (SYN; identically-housed) and Vivarium (VIV) controls. In the 2nd experiment, comparisons were made between dams centrifuged at 2-G, 1.75-G, 1.5-G, Rotational controls (1.08-G) or Stationary controls (1 G). Within three hours of recovery from either spaceflight or centrifugation, the dams' locomotor behavior was videotaped for 2 min. FLT dams showed dramatically reduced movement relative to both SYN and VIV control conditions, with significantly greater amounts of locomotor activity observed in SYN as compared to VIV dams. Significantly greater locomotor activity was observed in SYN as compared to VIV controls. In the second experiment, no differences were observed between dams exposed either 1, 1.5, 1.75, or 2-G. In both studies, the dams showed similar patterns of hindlimb rearing. Together, these findings provide quantitative evidence for decreased locomotor activity during re-adaptation to 1-g following spaceflight, but not centrifugation.

Johnson, K. E.; Ronca, A. E.; Alberts, J. R.



Cholesterol-independent endothelial dysfunction in virgin and pregnant rats fed a diet high in saturated fat  

PubMed Central

Western diets high in saturated fat are associated with an increased incidence of cardiovascular diseases. In this study we have evaluated vascular endothelial function and oxidative stress in virgin rats fed a normal (VC) or high in saturated fat diet (VHF) (20% lard and corn oil w/w) from weaning until adulthood, and throughout subsequent pregnancy (PC and PHF, respectively). The saturated fat diet was associated with enhanced noradrenaline sensitivity in small mesenteric arteries from VHF rats (VHF vs. VC, P < 0.05) and blunted endothelium-dependent relaxation in VHF and PHF rats (VHF vs. VC, P < 0.001; PHF vs. PC, P < 0.05). Endothelial dysfunction was attributable to a reduced nitric oxide component of relaxation in VHF rats, and blunted prostacyclin and endothelium-derived hyperpolarizing factor components in PHF rats. Other than plasma cholesterol, which was reduced in VHF and PHF rats, plasma lipids were normal. Fasting plasma insulin and glucose concentrations were raised in VHF rats (P < 0.05) and the plasma marker of oxidative stress, 8-iso PGF2?, was increased in PHF animals (P < 0.01). These findings suggest that endothelial dysfunction induced by a saturated fat diet is cholesterol independent and likely to be of different mechanistic origin in virgin and pregnant rats. PMID:10332106

Gerber, Robert T; Holemans, Kathleen; O'Brien-Coker, Ivan; Mallet, Anthony I; van Bree, Rita; Van Assche, F André; Poston, Lucilla



Repeated ethanol exposure affects the acquisition of spatial memory in adolescent female rats.  


Ethanol has been reported to disrupt spatial learning and memory in adolescent male rats. The present study was undertaken to determine the effects of ethanol on the acquisition of spatial memory in adolescent female rats. Adolescent female rats were subjected to repeated ethanol or saline treatments, and spatial learning was tested in the Morris water maze. For comparison, adult female rats were subjected to similar ethanol treatment and behavioral assessments as for adolescent rats. Ethanol-treated adolescent rats took longer and swam greater distances to find the hidden platform than saline controls. In the probe trial, ethanol-treated adolescent rats showed a trend towards reduced time spent in the target quadrant, and made significantly fewer target location crossings than saline-treated controls. Adult saline-treated control rats did not learn the spatial memory task as well as the adolescent saline-treated rats. Although ethanol in adult rats increased both latency and swim distance to find the platform, in the probe trial there was no difference between ethanol-treated adult rats and age-matched saline controls. Ethanol did not alter swim speed or performance in the cued visual task at either age. Together, these data suggest that ethanol specifically impairs the acquisition of spatial memory in adolescent female rats. Since adult females did not learn the task, ethanol-induced alterations in water maze performance may not reflect true learning and memory dysfunction. PMID:19463705

Sircar, Ratna; Basak, Ashim K; Sircar, Debashish



Effects of hyperstimulation with gonadotrophins and age of females on oocytes and their metaphase II status in rats.  


The present study was undertaken to evaluate the effects of hyperstimulation and aging on the number and proportion of oocytes in the metaphase II stage in female Wistar rats. It explored the validity of the hypothesis that a combination of hyperstimulation with pregnant mare serum gonadotrophins (PMSG) and age could compromise, to a greater extent, the oocyte quality as indicated by the proportion of ovulated oocytes in the metaphase II stage. Female Wistar rats were stimulated with varying doses of PMSG and human chorionic gonadotrophins (hCG) and the number and proportion of ovulated oocytes in the metaphase II stage were examined and compared between different groups of young adult (8-10 weeks old) and aging (30-32 weeks old) female rats. While spontaneous ovulation occurred in all young adult rats, only 50% of the aging rats did. The ovulation rate in aging rats was increased from 50 to 93% when non-PMSG-stimulated rats were given a dose of 10 IU of hCG at proestrus. The lower number of ovulated oocytes noted, even in those hyperstimulated with high doses of PMSG/hCG, also indicated a reduction in fertility in aging rats. Under the influence of high doses of PMSG, all aging rats ovulated, but as with the young adult rats, a higher dose of hCG was needed to achieve the maximum number of ovulated oocytes from the PMSG-induced expanded pool of preovulatory follicles. However, the average number of ovulated oocytes in aging rats was, nevertheless, still significantly lower than in young adult rats even when approximation of weight was considered. No consistent significant difference in proportion of normal oocytes was noted within groups and between young adult and aging rats. A lower proportion of ovulated oocytes was arrested at the metaphase II stages when rats, whether they were young adult or aging, were hyperstimulated with 40 IU of PMSG. However, this proportion was restored to normal (about 100%) when a higher dose of hCG, which is a signal responsible for initiating oocyte maturation, was used. Results of the present study showed that there appears to be an age-related reduction of sensitivity of the preovulatory follicles to the ovulation induction signal of hCG and thus higher doses of hCG were needed to ovulate the PMSG-induced expanded pool of dominant follicles. In older rats, apart from the obvious depletion of the pool of follicles, the evidence from the present study suggests that some of these older rats do have follicles, but that these were unable to develop to preovulatory follicles, probably because of the absence of sufficiently high levels of gonadotrophins essential for the initiation of folliculogenesis. PMSG-hyperstimulation can affect nuclear maturation; the proportion of ovulated oocytes not arrested at the metaphase II stage was higher. However, the proportion of ovulated oocytes at the metaphase II was restored to normal by increasing the dose of hCG use. Hence, meiotic aberration in rats is not age-dependent but rather dependent on the amplitude of the luteinizing hormone (LH)/hCG surge present. The results from this study nullified the hypothesis that hyperstimulation in combination with aging would lead to a higher proportion of abnormality in ovulated oocytes with respect to their being at inappropriate meiotic stages. PMID:10602280

Tain, C F; Goh, V H; Ng, S C



Effect of Carum carvi and Curcuma longa on hormonal and reproductive parameter of female rats  

Microsoft Academic Search

Background: Rhizome of Curcuma longa and seeds of Carum Carvi a folk medicinal plant used as have antifertility potentials. Present investigation study the effect of both the plant on hormone and reproductive parameter of female rat. The aqueous and ethanolic extract of rhizome of Curcuma longa and seeds of Carum Carvi used for testing antifertility activity in female rat. Aqueous

Shweta Thakur; Bhavana Bawara; Aditi Dubey; Durgesh Nandini; Nagendra Singh Chauhan; D. K. Saraf



The Effects of Alcohol and Age on Astrocytes In Female Rats Following an Inflammatory Stimulus  

E-print Network

THE EFFECTS OF ALCOHOL AND AGE ON ASTROCYTES IN FEMALE RATS FOLLOWING AN INFLAMMATORY STIMULUS A Senior Scholars Thesis by ASHLEY NICOLE SIMPSON Submitted to the Office of Undergraduate Research Texas A...&M University In partial fulfillment of the requirements for the designation as UNDERGRADUATE RESEARCH SCHOLAR April 2006 Major: Biology THE EFFECTS OF ALCOHOL AND AGE ON ASTROCYTES IN FEMALE RATS FOLLOWING...

Simpson, Ashley



Development of a physiologically based pharmacokinetic model to describe the disposition of methanol in pregnant rats and mice.  


Physiologically based pharmacokinetic (PBPK) models have been developed in recent years to describe the disposition of xenobiotics during gestation. These models can account for the dynamics of physiologic changes associated with pregnancy and represent a significant advantage in quantitatively assessing potential exposure of the conceptus. The PBPK approach was used to develop a model of methanol disposition during gestation in rats and mice. To validate this model, concentrations of methanol in the dam and the conceptus were determined after methanol exposure of rats on Gestational Day (gd) 14 and 20 and of mice on gd 18. At the developmental stages examined, the model provided a good description of methanol disposition in the maternal circulation and the conceptus of both species. Furthermore, the model was capable of providing good fits to methanol concentration-time data from the literature. In pregnant animals, conceptal/maternal AUC and Cmax ratios decreased with increasing dose at both gd 14 and gd 20 in the rat and at gd 18 in the mouse. Additionally, the conceptal/maternal diffusion constant ratio consistently decreased with increasing dose in pregnant rats and mice. These results are consistent with earlier observations that methanol limits its own delivery to the conceptus. Further experimentation is required to continue the process of developing a generalized PBPK model to describe the disposition of xenobiotics in pregnancy, to examine specific mechanisms of nonlinear conceptal methanol disposition, and to expand the model to extrapolate to low-dose human exposures. PMID:9266804

Ward, K W; Blumenthal, G M; Welsch, F; Pollack, G M



The effects of topiramate and sex hormones on energy balance of male and female rats  

Microsoft Academic Search

OBJECTIVE: The effects of topiramate (TPM) on components of energy balance were tested in male and female rats that were (i) left intact, (ii) castrated or (iii) castrated with replacement therapies consisting of testosterone administration in orchidectomized (OCX) rats and of estradiol or progesterone treatments in ovariectomized (OVX) rats.METHODS: TPM was mixed into the diet and administered at a dose

D Richard; F Picard; C Lemieux; J Lalonde; P Samson; Y Deshaies



Tissue distribution of YM758, a novel If channel inhibitor, in pregnant and lactating rats.  


In this study the tissue distribution of radioactivity in pregnant and lactating rats was investigated by quantitatively determining radioactivity concentrations and by whole-body autoradioluminograms after a single oral administration of 14C-YM758. In addition, the transfer of radioactivity into the reproductive tissues, foetus, and milk is discussed in terms of the localization of transporters in syncytiotrophoblast and mammary gland. The radioactivity concentrations in the liver were the highest of all the tissues and organs tested at all the sampling times. The radioactivity in main tissues (liver and kidney), including reproductive tissues (amniotic fluid, placenta, ovary, and uterus), was not retained for a long time, as in the plasma. The tissue/plasma (T/P) ratio of radioactivity in the foetus was below 1.0, which might be due to Mdr1-mediated export of YM758 into blood via the blood-placenta barrier since YM758 is a substrate for hMDR1, not for hBCRP/rBcrp. The T/P ratio of radioactivity in the maternal milk 1 and 4 h after oral administration of 14C-YM758 was 7.2 and 11.0, respectively. To understand better the distribution of new drugs into the reproductive tissues/milk, and to interpret further the results of reproductive safety studies for drug development, the contribution of transporters expressed in the blood-placenta barrier and mammary gland to the drug-transfer into placenta and milk should be considered. PMID:18800311

Umehara, K-I; Seya, K; Iwatsubo, T; Noguchi, K; Usui, T; Kamimura, H



Nociceptin inhibits uterine contractions in term-pregnant rats by signaling through multiple pathways.  


The actions of the endogenous peptide nociceptin (PNOC; previously abbreviated as N/OFQ) on the myometrium have not been investigated previously. Our aim was to study the presence and functional role of PNOC in the modulation of uterine contractility in pregnant rats at term. The presence of PNOC and its receptors (OPRL1; previously called NOP) in the uterus were detected by radioimmunoassay and radioligand-binding experiments. The PNOC-stimulated G protein activation was assessed by a [(35)S]GTPgammaS-binding technique. The effects of PNOC in uterine rings precontracted with KCl or oxytocin were also tested in vitro. Uterine levels of cAMP were measured by enzyme immunoassay. The K(+) channel blockers tetraethylammonium and paxilline were used to study the role of K(+) channels in mediating the uterine effects of PNOC. Both PNOC and OPRL1 were present in the uterus. PNOC revealed a maximum contraction inhibition of approximately 30%, which was increased to 40% by naloxone. Naloxone and pertussis toxin significantly attenuated the G protein-stimulating effect of PNOC. The uterine cAMP levels were elevated by PNOC and naloxone and after preincubation with pertussis toxin. Tetraethylammonium and paxilline reduced the contraction-inhibiting effect of PNOC and naloxone to approximately 10% and 15%, respectively. We presume that PNOC plays a role in regulating uterine contractility at term. Its effect is mediated partly by stimulatory heterotrimeric G (G(s)) proteins coupled to OPRL1 receptors and elevated cAMP levels, and also by Ca(2+)-dependent K(+) channels. Our results demonstrate a novel action and signaling pathway for PNOC that might be a potential drug target. PMID:20237332

Klukovits, A; Tekes, K; Gündüz Cinar, O; Benyhe, S; Borsodi, A; Deák, B H; Hajagos-Tóth, J; Verli, J; Falkay, G; Gáspár, R



Low-salt diet enhances vascular reactivity and Ca(2+) entry in pregnant rats with normal and reduced uterine perfusion pressure.  


Salt moderation is often recommended to prevent excessive increases in blood pressure during pregnancy, particularly in women who are prone to pregnancy-induced hypertension; however, the vascular effects of low dietary salt intake during pregnancy are unclear. We investigated whether a low-salt diet during pregnancy alters the mechanisms of vascular smooth muscle contraction. Active stress and (45)Ca(2+) influx were measured in endothelium-denuded aortic strips of virgin and normal pregnant Sprague-Dawley rats and a hypertensive pregnant rat model produced by reduction in uterine perfusion pressure (RUPP), fed either a normal-sodium (NS, 1% NaCl) or low-sodium diet (LS, 0.2% NaCl) for 7 days. The mean arterial pressure was as follows: virgin/NS 108 +/- 8, virgin/LS 117 +/- 7, pregnant/NS 102 +/- 3, pregnant/LS 117 +/- 4, RUPP/NS 119 +/- 3, and RUPP/LS 133 +/- 6 mm Hg. Phenylephrine (Phe) caused concentration-dependent increases in active stress and (45)Ca(2+) influx that were greater in RUPP rats than in normal pregnant or virgin rats and were enhanced in pregnant/LS and RUPP/LS compared with pregnant/NS and RUPP/NS, respectively. High KCl (16 to 96 mmol/L), which stimulates Ca(2+) entry from the extracellular space, also caused increases in active stress that were greater in RUPP than in normal pregnant, in pregnant/LS than in pregnant/NS, and in RUPP/LS than in RUPP/NS rats. The Phe-induced (45)Ca(2+) influx--active stress relation was greater in RUPP/NS than in pregnant/NS and was enhanced in pregnant/LS and RUPP/LS compared with pregnant/NS and RUPP/NS, respectively. In Ca(2+)-free (2 mmol/L ethylene glycol bis(beta-aminoethylether)-N,N,N',N'-tetra-acetic acid) Krebs, stimulation of intracellular Ca(2+) release by Phe (10(-5) mol/L) or caffeine (25 mmol/L) caused a transient contraction that was not significantly different in all groups of rats. Thus, a low-salt diet in pregnant and RUPP rats is associated with increases in vascular reactivity that involves Ca(2+) entry from the extracellular space but not Ca(2+) release from the intracellular stores. The enhancement of the Phe-induced Ca(2+) influx--active stress relation in pregnant and RUPP rats on a low-salt diet suggests activation of other vascular contraction mechanisms in addition to Ca(2+) entry. Although it is difficult to extrapolate the experimental data in rats to clinical data in women, the increased vascular reactivity and Ca(2+) entry and the possible enhancement of additional vascular contraction mechanisms with a low-salt diet suggest that reduction of dietary salt intake should be carefully monitored during pregnancy and pregnancy-induced hypertension. PMID:11882575

Giardina, Jena B; Cockrell, Kathy L; Granger, Joey P; Khalil, Raouf A



Selenium and Vitamin E Modulates Radiation-Induced Liver Toxicity in Pregnant and Nonpregnant Rat: Effects of Colemanite and Hematite Shielding  

Microsoft Academic Search

The levels of liver lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamins A and E were used to follow\\u000a the level of oxidative damage caused by ionizing radiation in pregnant rats. The possible protective effects of selenium and\\u000a vitamin E supplemented to rats housed in concrete-protected cages using hematite and colemanite were tested and compared to\\u000a untreated controls. Ninety-six rats

Osman Gençel; Mustafa Naziroglu; Ömer Çelik; Kadir Yalman; Dilek Bayram



Female rats are more susceptible to central nervous system oxygen toxicity than male rats  

PubMed Central

Abstract Tonic–clonic seizures typify central nervous system oxygen toxicity (CNS?OT) in humans and animals exposed to high levels of oxygen, as are encountered during scuba diving. We previously demonstrated that high doses of pseudoephedrine (PSE) decrease the latency to seizure (LS) for CNS?OT in young male rats. This study investigated whether female rats respond similarly to PSE and hyperbaric oxygen (HBO). We implanted 60 virgin stock (VS) and 54 former breeder (FB) female rats with radio?telemetry devices that measured brain electrical activity. One week later, rats were gavaged with saline or PSE in saline (40, 80, 120, 160, or 320 mg/kg) before diving to five atmospheres absolute in 100% oxygen. The time between reaching maximum pressure and exhibiting seizure was LS. Vaginal smears identified estrus cycle phase. PSE did not decrease LS for VS or FB, primarily because they exhibited low LS for all conditions tested. VS had shorter LS than males at 0, 40, and 80 mg/kg (?42, ?49, and ?57%, respectively). FB also had shorter LS than males at 0, 40, and 80 mg/kg (?60, ?86, and ?73%, respectively). FB were older than VS (286 ± 10 days vs. 128 ± 5 days) and weighed more than VS (299 ± 2.7 g vs. 272 ± 2.1 g). Males tested were younger (88 ± 2 days), heavier (340 ± 4.5 g), and gained more weight postoperatively (7.2 ± 1.6 g) than either VS (?0.4 ± 1.5 g) or FB (?1.6 ± 1.5 g); however, LS correlated poorly with age, body mass, change in body mass, and estrus cycle phase. We hypothesize that differences in sex hormones underlie females' higher susceptibility to CNS?OT than males. PMID:24771690

Held, Heather E.; Pilla, Raffaele; Ciarlone, Geoffrey E.; Landon, Carol S.; Dean, Jay B.



Adverse effects of 4-tert-octylphenol on the production of oxytocin and hCG in pregnant rats  

PubMed Central

Endocrine-disrupting chemicals (EDCs) are exogenous substances that alter the structure or function of the endocrine system. 4-Tert-octylphenol (OP) is one of the most representative EDCs and has estrogenic effects. In this study, we examined the effects of ethinyl estradiol (EE) and OP on the pituitary gland, placenta, and uterus of pregnant rats. Expression levels of human chorionic gonadotropin (hCG), oxytocin (OT), and contraction-associated proteins (CAPs) were determined, and uterine contractile activity was measured by uterine contraction assay. EE and OP both increased mRNA expression of OT and hCG in the pituitary gland but not the placenta. Since OT and hCG control uterine contraction, we next examined CAP expression in the uterus. Expression of 15-hydroxyprostaglandin-dehydrogenase (PGDH) was upregulated by OP, whereas expression of other CAPs was unaffected. To clarify the effect of OP on uterine contraction in pregnant rats, uterine contraction assay was performed. The 17?-Estradiol (E2) did not affect contraction of primary uterine cells harvested from pregnant rats in a 3D collagen gel model. However, OP showed different effects from E2 by significantly reducing contraction activity. In summary, we demonstrated that OP interferes with regulation of OT and hCG in the pituitary gland as well as PGDH in the uterus, thereby reducing uterine contraction activity. This result differs from the action of endogenous E2. Collectively, these findings suggest that exposure to EDCs such as OP during pregnancycan reduce uterine contractile ability, which may result in contraction-associated adverse effects such as metratonia, bradytocia, and uterine leiomyomata. PMID:25324873

Kim, Jun; Kang, Eun-Jin; Park, Mee-Na; Lee, Jae-Eon; Hong, So-Hye; An, Sung-Min; Kim, Seung-Chul; Hwang, Dae-Youn



Standardised Models for Inducing Experimental Peritoneal Adhesions in Female Rats  

PubMed Central

Animal models for adhesion induction are heterogeneous and often poorly described. We compare and discuss different models to induce peritoneal adhesions in a randomized, experimental in vivo animal study with 72 female Wistar rats. Six different standardized techniques for peritoneal trauma were used: brushing of peritoneal sidewall and uterine horns (group 1), brushing of parietal peritoneum only (group 2), sharp excision of parietal peritoneum closed with interrupted sutures (group 3), ischemic buttons by grasping the parietal peritoneum and ligating the base with Vicryl suture (group 4), bipolar electrocoagulation of the peritoneum (group 5), and traumatisation by electrocoagulation followed by closure of the resulting peritoneal defect using Vicryl sutures (group 6). Upon second look, there were significant differences in the adhesion incidence between the groups (P < 0.01). Analysis of the fraction of adhesions showed that groups 2 (0%) and 5 (4%) were significantly less than the other groups (P < 0.01). Furthermore, group 6 (69%) was significantly higher than group 1 (48%) (P < 0.05) and group 4 (47%) (P < 0.05). There was no difference between group 3 (60%) and group 6 (P = 0.2). From a clinical viewpoint, comparison of different electrocoagulation modes and pharmaceutical adhesion barriers is possible with standardised models. PMID:24809049

Kraemer, Bernhard; Wallwiener, Christian; Rajab, Taufiek K.; Brochhausen, Christoph; Wallwiener, Markus; Rothmund, Ralf



A Novel Telometric Metric for In-Situ Measurement of Intrauterine Pressure (IUP) in Pregnant and Parturient Rats  

NASA Technical Reports Server (NTRS)

During labor and birth, considerable forces exerted on fetuses help instigate certain adaptive postpartum responses (viz., breathing and suckling). To make precise, reliable measures of the forces experienced by rat fetuses during parturition, we developed a novel method for measuring intrauterine pressure (IUP) in late pregnant rats. A small (1.25 x 4cm) telemetric blood pressure sensor is fitted within a fluid-filled balloon, similar in size to a full term rat fetus. The balloon is surgically implanted in the uterus on Gestational Day 19 of the rats' 22-day pregnancy. During birth, dams are able to deliver their pups and the balloon. IUP arsenals are recorded during labor (G22 or 23) and birth. Data derived from a group of implanted rats indicated that pressures on the balloon increased across the period of birth, reaching 18 mmHg during labor, 25 mmHg during pup births and 39 mmHg just prior to delivery of the balloon. These data are within the range reported for conventional IUP measurement techniques. Dams are simultaneously videotaped, enabling us to analyze behavioral expressions of labor contractions and to integrate in-situ and behavioral findings.

Baer, Lisa A.; LaFramboise, M. N.; Hills, E. M.; Daly, M. E.; Mills, N. A.; Wade, C. E.; Ronca, A. E.; Dalton, Bonnie (Technical Monitor)



[The histochemical study of the effects of estrogen on the forebrain cholinergic neurons of fetal female rats transplanted into the anterior eye chamber of adult female rats].  


In order to clarify the effects of estrogen on cholinergic basal forebrain neurons, a cholinergic neuron in the diagonal band nucleus of the female fetal rat was implanted into the anterior eye chamber of the female adult rat. Some host rats were treated with 2mg estradiol valerate (E2v) injected every 3 days after ovariectomy while others were not 2 and 4 weeks after transplantation, the growth of cholinergic neurons in the graft was studied using acethylcholinesterase (AChE) histochemistry. At 2 weeks after transplantation, AChE positive neurons and fibers were densely distributed in the grafts of E2v treated rats. Also in grafts without E2v treatment, AChE positive neurons and fibers were found in all the grafts although their density was low. At 4 weeks, AChE staining was dense staining observed in both groups. These results indicate that neurotrophic effect of estrogen on the cholinergic basal forebrain neurons. PMID:8330655

Tanaka, K; Tamura, T; Kawashima, M; Ueda, S; Matsumoto, Y; Kawata, M; Ogino, Y; Yamamoto, T; Honjo, H; Okada, H



Effects of quercetin on CYP450 and cytokines in Aroclor 1254 injured endometrial cells of the pregnant rats.  


Polychlorinated biphenyls (PCBs) are widespread persistent residual environmental pollutants, which affect seriously the growth and reproductive alterations in humans and animals. Aroclor 1254 is a commercial mixture of PCBs. Quercetin is a flavonoid, which acts on estrogen receptors and causes the development of estrogen-related diseases. In this paper, the primary cultured endometrial cells in the pregnant rats were isolated and Aroclor 1254 was used to induce the injured endometrial cells model. The cells were treated with gradient quercetin, the viability of the endometrial cells, the expressions of CYP450, the contents of TNF-?, IL-6, estradiol (E2), and progesterone (P4) were measured. It showed that the viability of the cultured endometrial cells, the expression of CYP1A1 and CYP2B1, and the contents of TNF-?, E2, and IL-6 in the injured endometrial cells increased with the treatment of quercetin. It shows that quercetin has protective effect on the injured endometrial cells in the pregnant rats, this provide a basis on herbal medicine protection for animal reproductive diseases caused by environmental endocrine disruptors. PMID:24711995

Xu, Lina; Sun, Liyun; Lu, Liqin; Zhong, Xiuhui; Ma, Yuzhong; Qin, Jianhua



Effects of Quercetin on CYP450 and Cytokines in Aroclor 1254 Injured Endometrial Cells of the Pregnant Rats  

PubMed Central

Polychlorinated biphenyls (PCBs) are widespread persistent residual environmental pollutants, which affect seriously the growth and reproductive alterations in humans and animals. Aroclor 1254 is a commercial mixture of PCBs. Quercetin is a flavonoid, which acts on estrogen receptors and causes the development of estrogen-related diseases. In this paper, the primary cultured endometrial cells in the pregnant rats were isolated and Aroclor 1254 was used to induce the injured endometrial cells model. The cells were treated with gradient quercetin, the viability of the endometrial cells, the expressions of CYP450, the contents of TNF-?, IL-6, estradiol (E2), and progesterone (P4) were measured. It showed that the viability of the cultured endometrial cells, the expression of CYP1A1 and CYP2B1, and the contents of TNF-?, E2, and IL-6 in the injured endometrial cells increased with the treatment of quercetin. It shows that quercetin has protective effect on the injured endometrial cells in the pregnant rats, this provide a basis on herbal medicine protection for animal reproductive diseases caused by environmental endocrine disruptors. PMID:24711995

Xu, Lina; Sun, Liyun; Lu, Liqin; Qin, Jianhua



Extracts from rabbit skin inflamed by the vaccinia virus attenuate bupivacaine-induced spinal neurotoxicity in pregnant rats?  

PubMed Central

Extracts from rabbit skin inflamed by the vaccinia virus can relieve pain and promote repair of nerve injury. The present study intraperitoneally injected extracts from rabbit skin inflamed by the vaccinia virus for 3 and 4 days prior to and following intrathecal injection of bupivacaine into pregnant rats. The pain threshold test after bupivacaine injection showed that the maximum possible effect of tail-flick latency peaked 1 day after intrathecal injection of bupivacaine in the extract-pretreatment group, and gradually decreased, while the maximum possible effect in the bupivacaine group continued to increase after intrathecal injection of bupivacaine. Histological observation showed that after 4 days of intrathecal injection of bupivacaine, the number of shrunken, vacuolated, apoptotic and caspase-9-positive cells in the dorsal root ganglion in the extract-pretreatment group was significantly reduced compared with the bupivacaine group. These findings indicate that extracts from rabbit skin inflamed by the vaccinia virus can attenuate neurotoxicity induced by intrathecal injection of bupivacaine in pregnant rats, possibly by inhibiting caspase-9 protein expression and suppressing nerve cell apoptosis. PMID:25206391

Cui, Rui; Xu, Shiyuan; Wang, Liang; Lei, Hongyi; Cai, Qingxiang; Zhang, Hongfei; Wang, Dongmei




EPA Science Inventory

Developmental Atrazine Exposure Suppresses Immune Function in Male, but not Female Sprague-Dawley Rats Andrew A. Rooney,*,1 Raymond A. Matulka,? and Robert Luebke? *College of Veterinary Medicine, Anatomy, Physiological Sciences and Radiology, NCSU, Raleigh, North...


Regional differences in the pituitary distribution of luteinizing hormone in the gonadectomized and proestrous female rat  

EPA Science Inventory

Previous data have shown regional differences in the presence of anterior pituitary luteinizing hormone (LH) that generally correlate with comparable disparities in the distribution of gonadotropes throughout the gland. In female rats, the differences are apparent over the estro...


Evaluation of developmental toxicity induced by anticholinesterase insecticide, diazinon in female rats.  


Developmental toxicities, including birth defects, are significant public health problems. This study was planned to assess the cholinergic and developmental potentials of diazinon that is widely used as an organophosphate insecticide. Pregnant female Sprague-Dawley rats were given diazinon orally at doses of 0, 1.9, 3.8, and 7.6?mg/kg body weight (b.w.)/day on gestation days 6 to 15. Maternal brain acetylcholinesterase activities, measured on gestation day20, were significantly decreased at 3.8 and 7.6?mg/kg b.w./day, but fetal acetylcholinesterase activity was not altered. Maternal toxicities, as evidenced by cholinergic symptoms including diarrhea, tremors, weakness, salivation, and decreased activities, were observed at the 3.8 and 7.6?mg/kg b.w./day dose groups. Net gravid uterine weight was decreased at a dose of 7.6?mg/kg b.w./day. No maternal effects were apparent in the 1.9?mg/kg b.w./day dose group. Maternal toxicity at a dose of 3.8?mg/kg b.w./day did not induce fetotoxicity or teratogeneicity. However, 7.6?mg/kg b.w./day doses significantly resulted in fetal toxicity and malformations in addition to maternal toxicity in animals. In conclusion, teratogenic disorders only outlined by doses that produced marked maternal toxicity. Since the malformations were not morphologically related, they were considered to be secondary to maternal toxicity; hence, the malformations were not related to cholinesterase inhibition. PMID:21770030

Elmazoudy, Reda H; Attia, Azza A; Abdelgawad, Horeya S



Sex Steroid Regulation of the Inflammatory Response: Sympathoadrenal Dependence in the Female Rat  

Microsoft Academic Search

To investigate the role of sex steroids in sex differences in the response of rats to the potent inflammatory mediator bradykinin (BK), we evaluated the effect of sex steroid manipulation on the magnitude of BK-induced synovial plasma extravasation (PE). The magnitude of BK-induced PE is markedly less in females. Ovariectomy of female rats increased BK-induced PE, and administration of 17b-estradiol

Paul G. Green; Solbritt RantapaaDahlqvist; William M. Isenberg; Holly J. Strausbaugh; Frederick J.-P. Miao; Jon D. Levine



Effects of stress on nonassociative learning processes in male and female rats  

Microsoft Academic Search

In this study we assessed habituation and sensitization of the acoustic startle response (ASR) to discern whether intense,\\u000a inescapable stress affects nonassociative learning differently in male and female rats. Rats were inescapably stressed 2 hours\\u000a per day over 3 consecutive days. ASR magnitudes were measured at several times post-stress (1, 4, 8, and 15 days after cessation).\\u000a Females generally showed

Kevin D. Beck; Francis X. Brennan; Richard J. Servatius



Corticotrophin releasing factor (CRF) induced reinstatement of cocaine seeking in male and female rats  

PubMed Central

Significant sex differences have been demonstrated in clinical and preclinical studies of cocaine addiction, with some of the most consistent differences noted in regards to the role of stress and craving. The current study examined stress-induced reinstatement of cocaine seeking in male and female rats in an animal model of relapse using corticotropin-releasing factor (CRF) administration. Both male and female rats demonstrated increased cocaine seeking in response to CRF. CRF-induced reinstatement was highly variable across both male and female rats, and further analysis revealed a subpopulation that was particularly sensitive to CRF (high responders). Female high responders displayed significantly increased responding to CRF compared to males. Individual differences in stress responsivity could thus contribute to the likelihood of relapse, with females showing greater heterogeneity to stress-induced relapse. PMID:21889522

Buffalari, Deanne M.; Baldwin, Chelsey K.; Feltenstein, Matthew W.; See, Ronald E.



A cognitive rehabilitation paradigm effective in male rats lacks efficacy in female rats.  


Cognitive dysfunction, as a consequence of dementia, is a significant cause of morbidity lacking efficacious treatment. Females comprise at least half of this demographic but have been vastly underrepresented in preclinical studies. The current study addressed this gap by assessing the protective efficacy of physical exercise and cognitive activity on learning and memory outcomes in a rat model of vascular dementia. Forty ovariectomized Sprague-Dawley rats (?6 months old) were exposed to either a diet high in saturated fats and refined sugars or standard laboratory chow and underwent either chronic bilateral carotid occlusion or Sham surgery. Learning and memory abilities were evaluated using standard cognitive outcomes over the ensuing 6 months, followed by histologic analyses of hippocampal CA1 neurons. In Experiment 1, we confirmed hypoperfusion-induced cognitive dysfunction using a 2 × 2 (Surgery × Diet) experimental design, without alterations in hippocampal architecture. In Experiment 2, hypoperfused animals were either exposed to alternating days of physical (wheel running) and cognitive activity (modified Hebb-Williams maze) or sedentary housing. In contrast to males, this combination rehabilitation paradigm did not improve cognition or histopathologic outcomes in hypoperfused animals. These findings, highlighting differences between female and male animals, show the necessity of including both sexes in preclinical experimentation. PMID:25052554

Langdon, Kristopher D; Granter-Button, Shirley; Harley, Carolyn W; Moody-Corbett, Frances; Peeling, James; Corbett, Dale



Transient Receptor Potential C4/5 Like Channel Is Involved in Stretch-Induced Spontaneous Uterine Contraction of Pregnant Rat  

PubMed Central

Spontaneous myometrial contraction (SMC) in pregnant uterus is greatly related with gestational age and growing in frequency and amplitude toward the end of gestation to initiate labor. But, an accurate mechanism has not been elucidated. In human and rat uterus, all TRPCs except TRPC2 are expressed in pregnant myometrium and among them, TRPC4 are predominant throughout gestation, suggesting a possible role in regulation of SMC. Therefore, we investigated whether the TRP channel may be involved SMC evoked by mechanical stretch in pregnant myometrial strips of rat using isometric tension measurement and patch-clamp technique. In the present results, hypoosmotic cell swelling activated a potent outward rectifying current in G protein-dependent manner in rat pregnant myocyte. The current was significantly potentiated by 1µM lanthanides (a potent TRPC4/5 stimulator) and suppressed by 10µM 2-APB (TRPC4-7 inhibitor). In addition, in isometric tension experiment, SMC which was evoked by passive stretch was greatly potentiated by lanthanide (1µM) and suppressed by 2-APB (10µM), suggesting a possible involvement of TRPC4/5 channel in regulation of SMC in pregnant myometrium. These results provide a possible cellular mechanism for regulation of SMC during pregnancy and provide basic information for developing a new agent for treatment of premature labor.

Chung, Seungsoo; Kim, Young-Hwan; Joeng, Ji-Hyun



Disposition of diiosononyl phthalate and its effects on sexual development of the male fetus following repeated dosing in pregnant rats.  


Pregnant Sprague-Dawley rats received 50, 250, and 500 mg/kg/day diisononyl phthalate (DiNP) from GD 12 to 19 via corn oil gavage to study the dose response for effects on fetal male rat sexual development as well as metabolite disposition in the dam and fetus. Monoisononyl phthalate (MiNP), mono(carboxy-isooctyl) phthalate (MCiOP), mono(hydroxyl-isononyl) phthalate (MHiNP), mono(oxo-isononyl) phthalate (MOiNP), and monoisononyl phthalate glucuronide (MiNP-G) were found in all measured tissues. MCiOP was the major metabolite, followed in decreasing order by MiNP, MHiNP, MOiNP, and MiNP-G. Percentage of dose absorbed decreased at 750 mg/kg/day. Testosterone concentration in the fetal testes was reduced at 250 and 750 mg/kg/day. Multinucleated germ cells were increased in the testes of rats at 250 and 750 mg/kg/day. The no observed effect level (NOEL) for this study was 50 mg/kg/day based on increased MNGs and reduced testes testosterone concentration in the fetal rat. PMID:22813627

Clewell, Rebecca A; Sochaski, Mark; Edwards, Kendra; Creasy, Dianne M; Willson, Gabrielle; Andersen, Melvin E



Excess Androgen During Puberty Disrupts Circadian Organization in Female Rats  

PubMed Central

Circadian clocks have been described in each tissue of the hypothalamo-pituitary-ovarian axis. Although a role for the clock in the timing of ovulation is indicated, the impact of diseases that disrupt fertility on clock function or the clocks' role in the etiology of these pathologies has yet to be fully appreciated. Polycystic ovary syndrome (PCOS) is a particularly devastating endocrinopathy, affecting approximately 10% of women at childbearing age. Common features of PCOS are a polycystic ovary, amenorrhea, and excess serum androgen. Approximately 40% of these women have metabolic syndrome, including hyperinsulinemia, dyslipidemia, and hyperleptinemia. It has been suggested that excess androgen is a critical factor in the etiology of PCOS. We have examined the effects of androgen excess during puberty on the phase of circadian clocks in tissues of the metabolic and hypothalamo-pituitary-ovarian axes. Female period1-luciferase (per1-luc) rats were exposed to androgen (5?-dihydrotestosterone [DHT]) or placebo for 4-6 weeks (short term) or 9-15 weeks (long term). As expected, DHT-treated animals gained more weight than controls and had disrupted estrous cycles. At the end of treatment, tissues, including the liver, lung, kidney, white adipose, cornea, pituitary, oviduct, and ovarian follicles, were cultured, and per1-luc expression in each was recorded. Analysis of per1-luc expression revealed that DHT exposure increased phase distribution of multiple oscillators, including ovarian follicles, liver, and adipose, and altered phase synchrony between animals. These data suggest that excess androgen during puberty, a common feature of PCOS, negatively affects internal circadian organization in both the reproductive and metabolic axes. PMID:23417420

Murphy, Zachary C.; Menaker, Michael



Kin discrimination and female mate choice in the naked mole-rat Heterocephalus glaber.  

PubMed Central

Naked mole-rats are fossorial, eusocial rodents that naturally exhibit high levels of inbreeding. Persistent inbreeding in animals often results in a substantial decline in fitness and, thus, dispersal and avoidance of kin as mates are two common inbreeding avoidance mechanisms. In the naked mole-rat evidence for the former has recently been found. Here we address the latter mechanism by investigating kin recognition and female mate choice using a series of choice tests in which the odour, social and mate preferences of females were determined. Discrimination by females appears to be dependent on their reproductive status. Reproductively active females prefer to associate with unfamiliar males, whereas reproductively inactive females do not discriminate. Females do not discriminate between kin and non-kin suggesting that the criterion for recognition is familiarity, not detection of genetic similarity per se. In the wild, naked mole-rats occupy discrete burrow systems and dispersal and mixing with non-kin is thought to be comparatively rare. Thus, recognition by familiarity may function as a highly efficient kin recognition mechanism in the naked mole-rat. A preference by reproductively active females for unfamiliar males is interpreted as inbreeding avoidance. These findings suggest that, despite an evolutionary history of close inbreeding, naked mole-rats may not be exempt from the effects of inbreeding depression and will attempt to outbreed should the opportunity arise. PMID:10584337

Clarke, F M; Faulkes, C G



Changes in geometrical and biomechanical properties of immature male and female rat tibia  

NASA Technical Reports Server (NTRS)

The differences in the geometry and mechanical properties of immature male and female rat tibiae were detailed in order to provide comparative data for spaceflight, exercise, or disease experiments that use immature rats as an animal model. The experiment focuses on the particularly rapid period of growth that occurs in the Sprague-Dawley rat between 40 and 60 d of age. Tibial length and middiaphysical cross-sectional data were analyzed for eight different groups of rats according to age and sex, and tibial mechanical properties were obtained via three-point bending tests to failure. Results indicate that, during the 15 d period of rapid growth, changes in rat tibial geometry are more important than changes in bone material properties for influencing the mechanical properties of the tibia. Male tibiae changed primarily in structural properties, while in the female rats major changes in mechanical properties of the tibia were only attributable to changes in the structural properties of the bone.

Zernicke, Ronald F.; Hou, Jack C.-H.; Vailas, Arthur C.; Nishimoto, Mitchell; Patel, Sanjay




EPA Science Inventory

Three triazole fungicides were evaluated for effects on female rat reproductive development. Rats were exposed via feed to propiconazole (P) (100, 500, or 2500 ppm), myclobutanil (M) (100, 500, or 2000 ppm), or triadimefon (T) (100, 500, or 1800 ppm) from gestation day 6 to postn...


Endogenous oxytocin is involved in short-term olfactory memory in female rats  

Microsoft Academic Search

To investigate the involvement of oxytocin in their short-term lasting olfactory memory performance, adult female Wistar rats (n=12) were tested for their juvenile discrimination abilities. As measured by their exploratory behavior towards juveniles, the adult rats were able to discriminate between a previously exposed juvenile and a novel one as long as the interval between the two exposures was less

Mario Engelmann; Karl Ebner; Carsten T Wotjak; Rainer Landgraf



Osteoprotective Effect of Alfacalcidol in Female Rats with Systemic Chronic Inflammation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Studies have shown that alfacalcidol (a hydroxylated form of vitamin D) mitigates glucocorticoid-induced bone loss. This study was undertaken to explore the mechanism and bone microarchitecture of alfacalcidol in rats with systemic chronic inflammation. Thirty female rats (3-month-old) assigned to ...


Female Rats show a Bimodal Preference Response to the Artificial Sweetener Sucralose  

Microsoft Academic Search

The preference of female Sprague-Dawley rats for sucralose, a non-nutritive sweetener derived from sucrose, was evaluated in 23 h two-bottle tests with water or saccharin. Overall, the rats displayed weak or no preferences for sucralose (0.25-4 g\\/l) over water but strong preferences for saccharin (0.5-8 g\\/l) over water and saccharin (1 g\\/l) over sucralose (0.5 g\\/l). The rats also preferred

Anthony Sclafani; Richard A. Clare



Function of the Serotonin Transporter in Vasculature of the Female Rat: comparison with the male  

PubMed Central

Summary The serotonin transporter (SERT) handles serotonin (5-hydroxytryptamine, 5-HT) and is blocked by the antidepressant SERT inhibitors fluoxetine and fluvoxamine. While the importance of SERT in the central nervous system is clear, SERT also functions in the peripheral vasculature. We tested the hypothesis that vasculature from female rats has increased SERT function compared to male rats because females are more responsive to SERT inhibitors.In addition to in vitro experiments, we imposed the challenge of a 5-HT infusion via mini-pump (7 days) to investigate how males vs females handle chronically elevated levels of 5-HT. The SERT knockout (KO) and wild type (WT) rat were used.Blood vessels from the female (aorta, carotid artery, jugular vein and vena cava) took up 5-HT acutely in vitro in a SERT-dependent fashion (measured by HPLC). In isometric contractility experiments using isolated tissue baths, SERT affected contractility as evidenced by the 8-fold increase in potency of 5-HT in fluvoxamine-incubated WT aortae compared to control; fluvoxamine did not alter 5-HT-induced contraction in aortae from the SERT KO female rat. Infusion of 5-HT resulted in an increase in tissue 5-HT that was reduced to a larger extent in blood vessels from the female vs male SERT KO rat. Contraction to 5-HT in aortae from 5-HT-infused SERT KO rats was abolished compared to SERT WT rats.Collectively, these data suggest that SERT function, when challenged with 5-HT, is modestly more important in the vasculature of the female vs male rat. PMID:21371073

Linder, A. Elizabeth; Davis, Robert Patrick; Burnett, Robert; Watts, Stephanie W.



The incentive value of males' 50-kHz ultrasonic vocalizations for female rats (Rattus norvegicus).  


Rats emit ultrasonic vocalizations (USVs) of 22 kHz and 50 kHz before, during, and after copulation. The 50-kHz vocalizations can be subdivided into flat and frequency-modulated (FM) trill calls. In this study, the role of 50-kHz USVs in sexual incentive motivation in female rats was examined. USVs were recorded from sexually active males during the precopulatory phase. In the first two experiments, "full 10-min song," flat-call, and FM-trill-call stimuli were used. In Experiment 1, a combination of complex and trill calls was used as the FM-trill call, whereas a mixture of multistep and upward ramp calls was used in Experiment 2. The auditory stimuli were played back to sexually receptive female rats in a sexual incentive-motivation test. For comparison, the odor of an intact male rat was also used as incentive stimulus. The flat-call stimulus did not induce approach behavior in any experiment, whereas the FM trill showed a short-lived effect in Experiment 2. The females approached the "full song" during the first minute of stimulus exposure in Experiment 1, but not in Experiment 2. When the entire 10-min test period was analyzed, the females in Experiment 1 did not approach the full song more than background noise, though they did so in Experiment 2. The olfactory stimulus, to the contrary, had a clear incentive value in both experiments. In a third experiment, a devocalized male, an intact vocalizing male and a female rat were used as incentive stimuli. The females did not approach a vocalizing male more than they approached a silent male, showing that USVs do not contribute to the male rat's incentive value. Overall, the results of the present series of experiments show that the male rat's USVs do not have any consistent incentive value for the sexually receptive female rat. This sharply contrasts the strong and reliable effect of male odor. PMID:24040761

Snoeren, Eelke M S; Ågmo, Anders



Postnatal masculinization alters the HPA axis phenotype in the adult female rat.  


The ability of postnatal testosterone propionate (TP) to masculinize both behaviour and gonadal cyclicity in the female rat is well documented. We have investigated whether postnatal androgen also has an organizational effect on another sexually dimorphic neuroendocrine system--the hypothalamo-pituitary-adrenal (HPA) axis. Female rats were exposed to a single injection of testosterone propionate (TP) or oil within 24 h of birth. As adults, rats were either ovariectomized and given 17beta-oestradiol replacement (OVXE2) or sham ovariectomized with cholesterol implants (SHOVX). An automated sampling system collected blood from unanaesthetized adult female rats every 10 min over a 24-h period, during a mild psychological stress (noise) and following an immunological lipopolysaccharide stress (LPS). Neonatal TP-treated SHOVX rats had a significant reduction in the number, height, frequency and amplitude of corticosterone pulses over the basal 24-h period, compared to both the neonatal oil-treated and TP-treated OVXE2 animals. The corticosterone response to both noise and LPS was also significantly decreased for the TP-treated SHOVX females. Three hours post-LPS administration, TP females had significantly lower values of paraventricular nucleus (PVN) corticotrophin releasing hormone (CRH), arginine vasopressin (AVP) and anterior pituitary proopiomelanocortin (POMC) mRNAs and greater PVN glucocorticoid receptor (GR) mRNA expression compared to the oil-treated controls. E2 replacement in adult TP rats normalized all the mRNA levels, except for PVN GR mRNA which did fall towards the levels of the oil-control animals. A single injection of TP within 24 h of birth disrupts the development of the characteristic female pattern of corticosterone secretion and the normal female HPA response to stress, resulting in a pattern similar to that seen in males. These effects can be reversed by E2 treatment in the adult TP female rat. PMID:15611026

Seale, J V; Wood, S A; Atkinson, H C; Harbuz, M S; Lightman, S L




EPA Science Inventory

The distribution of carbaryl labeled with 14C in the ring, methyl or carbonyl groups was determined in pregnant mice and rats. Three identical concurrent experiments were performed using each of the three radiolabeled compounds in each of the species so that the different moietie...


Cell death in the development of the posterior cortex in male and female rats  

Microsoft Academic Search

ABSTRACT Work,from,our laboratory,has shown,that adult male,rats have,19% more,neurons,than female,rats in the binocular,region,and,18% more,in the monocular,region,of the primary visual cortex (Reid and Juraska [1992] J Comp Neurol 321:448 ? 455; Nun ˜ ez et al., [1999] Soc Neurosci Abstr 25:229). In the current experiment, we investigated whether cell death in male,and,female,rats (postnatal days 2?35) contributes,to the formation,of these differences. Using stereological

David M. Lauschke; Janice M. Juraska



Toxoplasma gondii influences aversive behaviors of female rats in an estrus cycle dependent manner.  


The protozoan Toxoplasma gondii (T. gondii) manipulates the behavior of its rodent intermediate host to facilitate its passage to its feline definitive host. This is accomplished by a reduction of the aversive response that rodents show towards cat odors, which likely increases the predation risk. Females on average show similar changes as males. However, behaviors that relate to aversion and attraction are usually strongly influenced by the estrus cycle. In this study, we replicated behavioral effects of T. gondii in female rats, as well as expanded it to two novel behavioral paradigms. We also characterized the role of the estrus cycle in the behavioral effects of T. gondii on female rats. Uninfected females preferred to spend more time in proximity to rabbit rather than bobcat urine, and in a dark chamber rather than a lit chamber. Infected females lost both of these preferences, and also spent more time investigating social novelty (foreign bedding in their environment). Taken together, these data suggest that infection makes females less risk averse and more exploratory. Furthermore, this effect was influenced by the estrus cycle. Uninfected rats preferred rabbit urine to bobcat urine throughout the cycle except at estrus and metestrus. In contrast, infected rats lost this preference at every stage of the cycle except estrus. Commensurate with the possibility that this was a hormone-dependent effect, infected rats had elevated levels of circulating progesterone, a known anxiolytic. PMID:24907696

Golcu, Doruk; Gebre, Rahiwa Z; Sapolsky, Robert M



An evaluation of the teratogenic potential of protracted exposure of pregnant rats to 2450-MHz microwave radiation. II. Postnatal psychophysiologic analysis.  


The objective of this study was to determine whether protracted prenatal exposure of rats to 2450-MHz microwave radiation at a power density level of 20 mW/cm2 would significantly alter postnatal growth and psychophysiologic development. Of 75 pregnant rats, 12 were exposed to microwave radiation, 4 sham-irradiated, and 59 served as environmental control animals. Forty-five females were allowed to deliver their offspring. The neonates were examined and weighed on d 3 and weekly thereafter until 87 d of age. Neonatal reflex tests were initiated as early as d 3 (surface righting, air righting, auditory startle, visual placing). One physiologic parameter, eye opening, was also observed. Mothers were rebred 10 d after weaning and a morphologic evaluation was completed on the second litter. Behavioral tests were begun at 60 d of age and included water T-maze, conditioned avoidance response, open field, activity wheel, forelimb hanging, and swimming. At 90 d of age offspring were bred within and across groups, and a morphologic teratologic analyses was completed on the offspring. Representative tissue samples were collected and organ weights recorded for the brain, liver, kidneys, and gonads of all animals. Analyses of the data indicated that there were no significant malformations or significant alterations in the neonatal physiologic or reflex test results, body/organ weight ratios, or breeding results in the adult offspring. There were no significant alterations in five of the six adult behavioral tests. There were significant differences in activity among the irradiated and control offspring between the sexes, the irradiated offspring being more active. These results are indicative of possible radiation-induced behavioral alterations. Further studies are needed to explore the possibility of microwave radiation-related alterations in animal behavior. PMID:6827624

Jensh, R P; Vogel, W H; Brent, R L



Orexin-1 Receptor Mediation of Cocaine Seeking in Male and Female Rats  

PubMed Central

Previous studies have shown that female rats exhibit enhanced cocaine seeking during multiple phases of cocaine addiction compared with males. The orexin/hypocretin system recently has been implicated in drug addiction in male rats. Based on the known sex differences in cocaine addiction, in the current study we examined orexin-mediated cocaine seeking during self-administration, extinction, and reinstatement in age-matched male (initial weight 250–300 g) and female (initial weight 175–225 g) Sprague-Dawley rats by using the orexin-1 receptor (OX1R) antagonist 1-(2-methylbenzoxazol-6-yl)-3-[1,5]naphthyridin-4-yl urea (SB-334867) (10–30 mg/kg). OX1R blockade had no effect on established cocaine self-administration, but attenuated cocaine seeking during extinction in both male and female rats. It is noteworthy that OX1R blockade potently attenuated cue-induced reinstatement in males but had no effect on females. SB-334867 also reduced cocaine seeking during pharmacological stress-induced (yohimbine, 2.5 mg/kg) and yohimbine + cue-induced reinstatement in both sexes. SB-334867 failed to affect reinstatement induced by cocaine (10 mg/kg) in either male or female rats, but selectively reduced cocaine + cue-induced reinstatement only in males. In separate experiments examining basal and cocaine-induced locomotion, SB-334867 attenuated locomotion in both male and female rats. Finally, assessment of plasma and brain levels of SB-334867 showed that estrus females had slightly higher plasma levels than diestrus females, but no overall sex differences or estrous cycle differences were observed in plasma or brain SB-334867 concentrations. These results show that OX1R signaling plays a role in mediating cocaine seeking, but differs between the sexes for cue-induced reinstatement. PMID:22186370

Zhou, Luyi; Ghee, Shannon M.; Chan, Clifford; Lin, Li; Cameron, Michael D.; Kenny, Paul J.



Placental Lactogen Administration Reverses the Effect of Low-Protein Diet on Maternal and Fetal Serum Somatomedin Levels in the Pregnant Rat  

Microsoft Academic Search

Female rats were studied on day 20 of pregnancy after being fed either a 5% lactalbumin (low protein) diet or a 20% lactalbumin (adequate) diet for the last 2 weeks of pregnancy. Rats on the lower intake of protein showed decreased serum levels of rat placental lactogen and reduced numbers of lactogenic receptors in the maternal liver. These changes were

S. J. Pilistine; A. C. Moses; H. N. Munro




PubMed Central

In an earlier study, we reported that daily fluoxetine treatment (10 mg/kg/day) rapidly disrupted estrous cyclicity and sexual receptivity in adult, regularly cycling Fischer rats. The current study was designed to investigate if comparable fluoxetine treatment would similarly affect intact, regularly cycling Sprague Dawley rats. In the first experiment, fluoxetine was injected for 24 days. After 11–14 days of daily fluoxetine treatment, 40% of the rats showed a transient disturbance of the estrous cycle with elimination of sexual receptivity. In these affected rats, reduced sexual receptivity generally preceded disruption of vaginal cyclicity. In a second experiment, a shorter exposure was used to attempt to dissociate effects of fluoxetine on behavior and estrous cyclicity. Nine days of fluoxetine treatment eliminated sexual receptivity and proceptivity (hops/darts) in 40% and 46%, respectively, of rats without altering the estrous cycle. Female rats then received a 10th fluoxetine injection 30 min prior to assessment of sexual motivation (measured with the male preference paradigm). There was no effect of fluoxetine on male preference, but fluoxetine significantly reduced the number of crossings and seconds of grooming during preference testing. Therefore, effects of fluoxetine on estrous cyclicity and behavior of Sprague Dawley female rats were smaller and required longer to develop than previously reported in Fischer female rats. These findings reinforce a probable relationship between fluoxetine’s effect on sexual activity and neuroendocrine disturbances and illustrate the importance of strain selection in attempting to model human disease. PMID:18929547

Maswood, Navin; Sarkar, Jhimly; Uphouse, Lynda



Exercise training attenuates acute hyperalgesia in streptozotocin-induced diabetic female rats  

PubMed Central

OBJECTIVES: We investigated the effects of chronic (eight weeks) low- to moderate-intensity swimming training on thermal pain sensitivity in streptozotocin-induced diabetic female rats. METHODS: Female Wistar rats (n?=?51) were divided into the following groups: trained streptozotocin-induced diabetic rats [hyperglycemic trained (HT)], sedentary streptozotocin-induced diabetic rats [hyperglycemic sedentary (HS)], normoglycemic trained rats (NT) and normoglycemic sedentary rats (NS). Diabetes was induced by a single injection of streptozotocin (50 mg/kg, i.p.). One day after the last exercise protocol (60 min/day, five days/week for eight weeks) in the trained groups or after water stress exposure (ten min/twice a week) in the sedentary groups, the rats were subjected to a hot plate test. RESULTS: After eight weeks of swimming training, streptozotocin-induced diabetic rats presented a significantly lower body mass (trained: 219.5±29 g, sedentary: 217.8±23 g) compared with the normoglycemic groups (trained: 271±24 g, sedentary: 275.7±32 g). Interestingly, we did not find differences in blood glucose levels (mg/dl) between the trained and sedentary groups of the hyperglycemic or normoglycemic rats (HT: 360.2±66.6, HS: 391.7±66.7, NT: 83.8±14.0, NS: 77.5±10.1). In the hot plate test, the rats from the HT group presented a significantly lower latency than the other rats (HT: 11.7±7.38 s, HS: 7.02±7.38 s, NT: 21.21±7.64 s, NS: 22.82±7.82 s). CONCLUSION: Low-to-moderate swimming training for a long duration reduces thermal hyperalgesia during a hot plate test in streptozotocin-induced diabetic female rats. PMID:22179169

Rossi, Denise M.; Valenti, Vitor E.; Navega, Marcelo T.



Medial Prefrontal Cortex Lesions in the Female Rat Affect Sexual and Maternal Behavior and Their Sequential Organization  

E-print Network

Sexual and maternal behavior in the female rat consists of several stereotyped components, regulated in open-ended, unstructured, or dynamic environments. In rats, lesions of the mPFC produce deficits

Sokolowski, Marla


Social transmission of Pavlovian fear: fear-conditioning by-proxy in related female rats.  


Pairing a previously neutral conditioned stimulus (CS; e.g., a tone) to an aversive unconditioned stimulus (US; e.g., a foot-shock) leads to associative learning such that the tone alone will elicit a conditioned response (e.g., freezing). Individuals can also acquire fear from a social context, such as through observing the fear expression of a conspecific. In the current study, we examined the influence of kinship/familiarity on social transmission of fear in female rats. Rats were housed in triads with either sisters or non-related females. One rat from each cage was fear conditioned to a tone CS+ shock US. On day two, the conditioned rat was returned to the chamber accompanied by one of her cage mates. Both rats were allowed to behave freely, while the tone was played in the absence of the foot-shock. The previously untrained rat is referred to as the fear-conditioned by-proxy (FCbP) animal, as she would freeze based on observations of her cage-mate's response rather than due to direct personal experience with the foot-shock. The third rat served as a cage-mate control. The third day, long-term memory tests to the CS were performed. Consistent with our previous application of this paradigm in male rats (Bruchey et al. in Behav Brain Res 214(1):80-84, 2010), our results revealed that social interactions between the fear conditioned and FCbP rats on day two contribute to freezing displayed by the FCbP rats on day three. In this experiment, prosocial behavior occurring at the termination of the cue on day two was significantly greater between sisters than their non-sister counterparts, and this behavior resulted in increased freezing on day three. Our results suggest that familiarity and/or kinship influences the social transmission of fear in female rats. PMID:24310150

Jones, Carolyn E; Riha, Penny D; Gore, Andrea C; Monfils, Marie-H



Effect of exogenous melatonin on neuroendocrine-reproductive function of middle-aged female rats.  


The possible role of melatonin in the regulation of the reproductive system of female rats during ageing was investigated in middle-aged female rats showing irregular duration of the oestrous cycle (n = 30). Blood samples were obtained by jugular venepuncture during the oestrous cycle in control rats. After this experiment was completed, the female rats were treated with melatonin for 2 months and blood samples were obtained at different stages of the oestrous cycle. Plasma LH, FSH and prolactin concentrations were significantly increased in the afternoon of the day of pro-oestrus after melatonin treatment compared with control rats. Moreover, FSH concentrations too were significantly increased on the morning of pro-oestrus and oestrus in melatonin treated rats compared with control rats. Similarly, oestradiol concentrations were significantly higher on the morning of pro-oestrus in melatonin treated rats compared with controls. Another group of rats showing irregular duration of the oestrous cycle was used to study the possible effect of melatonin treatment on the timing of pro-oestrous surges of LH and FSH. The results showed that LH and FSH peak values occurred at 5 h after melatonin treatment. Pituitary responsiveness to LHRH in a 90 min test was also studied in middle-aged rats showing irregular duration of the oestrous cycle that had been injected for 1 month with either melatonin or saline. Prolactin response was unaffected by exogenous melatonin, but a stimulatory effect of melatonin on LH and FSH pituitary responsiveness to LHRH was observed. The results indicate an improved function of the neuroendocrine-reproductive axis in middle-aged rats after melatonin treatment. PMID:10690201

Díaz, E; Fernández, C; Castrillón, P O; Esquifino, A I; Marín, B; Díaz López, B



Teratogenic and Carcinogenic Effects in the Offspring after Single Injection of Ethylnitrosourea to Pregnant Rats  

Microsoft Academic Search

ALKYLNITROSOUREAS give the corresponding alkylating diazoalkanes on heterolysis, and are potent carcinogens, selectively producing malignant tumours in the brain1 and peripheral nerves2 of rats. As might be expected, mothylnitrosourea is also mutagenic as in Saccharomyces cerevisiae3 and is teratogenic in rats4. In teratogenesis investigations the embryos are generally killed and examined immediately after Caesarean delivery. If, however, only slight teratogenic

H. Druckrey; S. Ivankovic; R. Preussmann




EPA Science Inventory

The purpose of this study was to evaluate the effect(s) of acute in vivo cadmium exposure on steroidogenesis in rat ovaries during different reproductive states. prague-Dawley rats were injected subcutaneously on the day of diestrus, or on day 7 or 16 of gestation with a single d...


Prenatal choline availability modulates hippocampal neurogenesis and neurogenic responses to enriching experiences in adult female rats.  


Increased dietary intake of choline early in life improves performance of adult rats on memory tasks and prevents their age-related memory decline. Because neurogenesis in the adult hippocampus also declines with age, we investigated whether prenatal choline availability affects hippocampal neurogenesis in adult Sprague-Dawley rats and modifies their neurogenic response to environmental stimulation. On embryonic days (ED) 12-17, pregnant rats ate a choline-supplemented (SUP-5 g/kg), choline sufficient (SFF-1.1 g/kg), or choline-free (DEF) semisynthetic diet. Adult offspring either remained in standard housing or were given 21 daily visits to explore a maze. On the last ten exploration days, all rats received daily injections of 5-bromo-2-deoxyuridine (BrdU, 100 mg/kg). The number of BrdU+ cells was significantly greater in the dentate gyrus in SUP rats compared to SFF or DEF rats. While maze experience increased the number of BrdU+ cells in SFF rats to the level seen in the SUP rats, this enriching experience did not alter cell proliferation in DEF rats. Similar patterns of cell proliferation were obtained with immunohistochemical staining for neuronal marker doublecortin, confirming that diet and exploration affected hippocampal neurogenesis. Moreover, hippocampal levels of the brain-derived neurotrophic factor (BDNF) were increased in SUP rats as compared to SFF and DEF animals. We conclude that prenatal choline intake has enduring effects on adult hippocampal neurogenesis, possibly via up-regulation of BDNF levels, and suggest that these alterations of neurogenesis may contribute to the mechanism of life-long changes in cognitive function governed by the availability of choline during gestation. PMID:17445242

Glenn, Melissa J; Gibson, Erin M; Kirby, Elizabeth D; Mellott, Tiffany J; Blusztajn, Jan K; Williams, Christina L



/sup 20/neon ion- and x-ray-induced mammary carcinogenesis in female rats  

SciTech Connect

One of the proposed uses of heavy ion irradiation is to image lesions of the human female breast. The rat model system was chosen to assess the carcinogenic potential of heavy ion irradiation in the belief that data obtained from rat studies would have a qualitatively predictive value for the human female. Accordingly, female rats were exposed to /sup 20/Ne ions at the BEVALAC and studied for the development of mammary neoplasia for 312 +- 2 days at Brookhaven along with rats exposed concurrently to x-irradiation or to no irradiation. As the dose of either type of radiation was increased the percent of rats with mammary adenocarcinomas, and the percent of rats with mammary fibroadenomas, tended to increase. At a prevalence of 20%, the RBE for /sup 20/Neon ions for mammary adenocarcinomas was estimated to be larger than 5 and for mammary fibroadenomas the RBE was estimated to be less than 2. No conclusion was reached concerning whether or not the RBE might vary with dose. We suggest that /sup 20/Ne ions do have a carcinogenic potential for rat mammary tissue and that this carcinogenic potential is likely to be greater than for x-irradiation. (DT)

Shellabarger, C.J.; Baum, J.W.; Holtzman, S.; Stone, J.P.



Metabolism and physiologically based pharmacokinetic modeling of flumioxazin in pregnant animals.  


A physiologically based pharmacokinetic (PBPK) model was developed to predict the concentration of flumioxazin, in the blood and fetus of pregnant humans during a theoretical accidental intake (1000mg/kg). The data on flumioxazin concentration in pregnant rats (30mg/kg po) was used to develop the PBPK model in pregnant rats using physiological parameters and chemical specific parameters. The rat PBPK model developed was extrapolated to a human model. Liver microsomes of female rats and a mixed gender of humans were used for the in vitro metabolism study. To determine the % of flumioxazin absorbed after administration at a dose of 1000mg/kg assuming maximum accidental intake, the biliary excretion study of [phenyl-U-(14)C]flumioxazin was conducted in bile duct-cannulated female rats (Crl:CD (SD)) to collect and analyze the bile, urine, feces, gastrointestinal tract, and residual carcass. The % of flumioxazin absorbed at a dose of 1000mg/kg in rats was low (12.3%) by summing up (14)C of the urine, bile, and residual carcass. The pregnant human model that was developed demonstrated that the maximum flumioxazin concentration in the blood and fetus of a pregnant human at a dose of 1000mg/kg po was 0.86?g/mL and 0.68?g/mL, respectively, which is much lower than Km (202.4?g/mL). Because the metabolism was not saturated and the absorption rate was low at a dose of 1000mg/kg, the calculated flumioxazin concentration in pregnant humans was thought to be relatively low, considering the flumioxazin concentration in pregnant rats at a dose of 30mg/kg. For the safety assessment of flumioxazin, these results would be useful for further in vitro toxicology experiments. PMID:24717917

Takaku, Tomoyuki; Nagahori, Hirohisa; Sogame, Yoshihisa



Cognitive differences between male and female rats following exposure to 56Fe particles  

NASA Astrophysics Data System (ADS)

On exploratory class missions astronauts will be exposed to types and doses of radiation (HZE particles) that are not experienced in low earth orbit. While it is likely that the crew will consist of both male and female astronauts, there has been little research on the effects of exposure to HZE particles on cognitive performance in female subjects. While previous research has shown that exposure to HZE particles disrupts cognitive performance in male rats it remains to be established whether or not similar effects will occur with female subjects because estrogen may act as a neuroprotectant. Ovariectomized (OVX) female rats were obtained from Taconic Farms. Thirty mm segments of silastic tubing containing either 180 pg l7-estradiol/mL in sesame oil or vehicle alone were implanted subcutaneously in the neck. Three days following surgery the rats were exposed to 56Fe particles (1000 MeV/n, 0-200 cGy) at the NSRL. Following irradiation the rats were shipped to UMBC for behavioral testing. The results indicated that the pattern of decrements in cognitive performance differed between male and female rats. In addition, for female rats, there were differences in performance as a function of the presence or absence of estradiol. In the vehicle implanted subjects exposure to 56Fe particles did not affect operant responding on an ascending fixed-ratio schedule; whereas irradiation did disrupt responding in OVX animals given estradiol. These results suggest that estrogen may not be protective following exposure to HZE particles. This research was supported by Grant NNX08AM66G from NASA.

Rabin, Bernard; Shukitt-Hale, Barbara; Carrihill-Knoll, Kirsty; Luskin, Katharine; Long, Lauren; Joseph, James


Y are you not pregnant: identification of Y chromosome segments in female cattle with decreased reproductive efficiency  

Technology Transfer Automated Retrieval System (TEKTRAN)

Reproductive efficiency is of economic importance in commercial beef cattle production, as failure to achieve pregnancy reduces the number of calves marketed. Identification of genetic markers with predictive merit for reproductive success would facilitate early selection of females and avoid ineff...


Neonatal sex steroids affect responses to Seoul virus infection in male but not female Norway rats  

Microsoft Academic Search

Previous studies illustrate that after inoculation with Seoul virus (i.e., the naturally occurring hantavirus found in Norway rats), adult male rats produce higher antibody responses, exhibit higher Th1 responses (i.e., IgG2a, IL-2, and IFN?), and shed virus longer than females, but these difference are not altered by manipulation of sex steroids in adulthood. To determine whether sex steroid hormones organize

Sabra L. Klein; Aimee L. Marson; Alan L. Scott; Gary Ketner; Gregory E. Glass



Antifertility Activity of Steroidal Extract of Trigonella foenum-graecum (seeds) in Female Rats  

Microsoft Academic Search

Healthy adult female albino rats (Rattus norvegicus) were fed orally with steroidal extract of Trigonella foenum-graecum (100 mg\\/day\\/rat for 15 days). The data revealed that the body weights were not affected but the weights of ovary and uterus declined. The biochemical parameters viz., protein, sialic acid, glycogen and ascorbic acid were reduced in ovary and uterus, however the concentration of

J. D. Sharma; Anjula Bhinda


The ameliorative effects of Eurycoma longifolia Jack on testosterone-induced reproductive disorders in female rats.  


The objective of this research was to study the ameliorative effects of a standardized quassinoid-rich extract (TAF 273) of Eurycoma longifolia root on some reproductive disorders in female rats. An irregular estrous cycle and ovarian cystic follicles were induced in 21-day-old females by the daily administration of testosterone (10 mg/kg, sc) for three weeks. The hormone-treated rats exhibited persistent diestrous as well as ovaries containing cystic follicles. Upon treatment with TAF 273, fewer animals showed irregular estrous cycles and there was less follicular morphological damage. The reversal effect may be derived from the anti-estrogenic properties of the plant quassinoids. PMID:22850474

Abdulghani, Mahfoudh; Hussin, Abas Hj; Sulaiman, Siti Amrah; Chan, Kit Lam



A parametric analysis of olanzapine-induced weight gain in female rats  

Microsoft Academic Search

Rationale  Some novel antipsychotics, including olanzapine, induce weight gain and metabolic abnormalities, which represent the major\\u000a adverse effects of these drugs. However, the mechanism(s) involved in such effects are unclear.\\u000a \\u000a \\u000a \\u000a Objective  The aim of this study was to develop, in female rats, a parametric model of olanzapine-induced weight gain and metabolic abnormalities\\u000a and evaluate it against clinical findings.\\u000a \\u000a \\u000a \\u000a Methods  Female rats were administered

G. D. Cooper; L. C. Pickavance; J. P. H. Wilding; J. C. G. Halford; A. J. Goudie



The metabolic clearance of progesterone in the pregnant rat: Absence of a physiological role for the lung  

SciTech Connect

The metabolic clearance rate (MCR) of progesterone is among the highest for all steroid hormones studied, yet it is difficult to apportion this high MCR to specific organ contributions. The isolated lung has been shown to metabolize progesterone, and since this tissue receives the entire cardiac output, potentially it could make a major contribution to the overall MCR. This possibility was examined in the present study by measuring lung extraction of (3H)progesterone under steady-state conditions in the intact pregnant rat. Anesthetized rats (n = 6) were infused with (3H)progesterone via a femoral vein for 100 min on Day 16 of pregnancy. After the onset of steady state (40 min), four blood samples were obtained at 20-min intervals from the right ventricle and from the aorta, and the concentrations of (3H)progesterone and its metabolites were determined. Throughout the sampling period, mean arterial pressure and heart rate remained stable (two-way analysis of variance), as did the production rate (3.76 +/- 0.35 mg/day; mean +/- SEM) and the MCR (34.8 +/- 3.5 ml/min) of progesterone. Despite this high rate of clearance, there was no difference between the concentration of (3H)progesterone in arterial and right ventricular blood, indicating no net extraction of progesterone during passage through the lung. Furthermore, there was no change in the concentration of either lipid-soluble or aqueous-soluble (3H)progesterone metabolites during trans-lung passage. These observations demonstrate that the lung does not contribute to the MCR of progesterone when measured under physiological and steady-state conditions. Therefore, the relationship, MCR (ml/min) = whole-body extraction (%) x cardiac output (ml/min), is upheld for progesterone in the rat.

Waddell, B.J.; Bruce, N.W. (Univ. of Western Australia, Nedlands)



Effects of Obesity on Bone Mass and Quality in Ovariectomized Female Zucker Rats  

PubMed Central

Obesity and osteoporosis are two chronic conditions that have been increasing in prevalence. Despite prior data supporting the positive relationship between body weight and bone mineral density (BMD), recent findings show excess body weight to be detrimental to bone mass, strength, and quality. To evaluate whether obesity would further exacerbate the effects of ovariectomy on bone, we examined the tibiae and fourth lumbar (L4) vertebrae from leptin receptor-deficient female (Leprfa/fa) Zucker rats and their heterozygous lean controls (Leprfa/+) that were either sham-operated or ovariectomized (Ovx). BMD of L4 vertebra was measured using dual-energy X-ray absorptiometry, and microcomputed tomography was used to assess the microstructural properties of the tibiae. Ovariectomy significantly (P < 0.001) decreased the BMD of L4 vertebrae in lean and obese Zucker rats. Lower trabecular number and greater trabecular separation (P < 0.001) were also observed in the tibiae of lean- and obese-Ovx rats when compared to sham rats. However, only the obese-Ovx rats had lower trabecular thickness (Tb.Th) (P < 0.005) than the other groups. These findings demonstrated that ovarian hormone deficiency adversely affected bone mass and quality in lean and obese rats while obesity only affected Tb.Th in Ovx-female Zucker rats. PMID:25309751

Feresin, Rafaela G.; Johnson, Sarah A.; Elam, Marcus L.; Arjmandi, Bahram H.



Chronic effects of atrazine on estrus and mammary tumor formation in female Sprague?Dawley and Fischer 344 rats  

Microsoft Academic Search

The chronic effects of dietary administration of atrazine at levels as high as 400 ppm on selected endocrine and tumor profiles were evaluated in Fischer 344 and Sprague?Dawley female rats. The study showed that lifetime dietary administration of atrazine at a maximum tolerated dose (MTD) to Sprague?Dawley female rats caused (1) lengthening of the estrous cycle, (2) increased number of

Lawrence T. Wetzel; Louis G. Luempert III; Charles B. Breckenridge; Merrill O. Tisdel; James T. Stevens; Ajit K. Thakur; Pamela J. Extrom; J. Charles Eldridge



Exercise improves learning and memory impairments in sleep deprived female rats.  


Inadequate sleep is a common problem in modern societies. It has been previously shown that female rats are more vulnerable to the deleterious effects of sleep deprivation on cognitive functions. Physical exercise has been suggested to attenuate the cognitive impairments induced by sleep deprivation in male rats. The objective of the current study was to investigate the effects of physical exercise on cognitive functions of female rats following paradoxical sleep deprivation. Intact and ovariectomized (OVX) female Wistar rats were used in the present study. The exercise protocol was 4 weeks of treadmill running. The multiple platform method was applied for the induction of 72h paradoxical sleep deprivation and the cognitive function was evaluated using Morris water maze (MWM). Plasma corticosterone level was evaluated in separate groups of study. ANOVA and repeated measures were used to analyze the data and P<0.05 was considered statistically significant. Throughout the investigation, significant learning impairment was observed in sleep-deprived OVX rats compared to the intact and the other OVX groups. Short term memory impairment was observed in both sleep-deprived OVX and intact groups. Physical exercise alleviated the PSD-induced learning and memory impairments in both intact and OVX groups. Corticosterone levels were not statistically significant among the different groups. The results of our study confirmed the negative effects of PSD on cognitive functions in female rats and regular physical exercise seems to protect rats from these effects. Further studies are suggested to be carried out in order to evaluate the possible underlying mechanisms, and also to evaluate the possible interactions between sex hormones and PSD-induced cognitive impairments. PMID:25447468

Saadati, Hakimeh; Esmaeili-Mahani, Saeed; Esmaeilpour, Khadije; Nazeri, Masoud; Mazhari, Shahrzad; Sheibani, Vahid



Post-weaning social isolation of female rats, anxiety-related behavior, and serotonergic systems  

PubMed Central

Our previous studies have shown that post-weaning social isolation of male rats leads to sensitization of serotonergic systems and increases in anxiety-like behavior in adulthood. Although studies in humans suggest that females have an increased sensitivity to stress and risk for the development of neuropsychiatric illnesses, most studies involving laboratory rats have focused on males while females have been insufficiently studied. The objective of this study was to investigate the effects of post-weaning social isolation on subsequent responses of an anxiety-related dorsal raphe nucleus (DR)-basolateral amygdala system to pharmacological challenge with the anxiogenic drug, N-methyl-beta-carboline-3-carboxamide (FG-7142; a partial inverse agonist at the benzodiazepine allosteric site on the ?-aminobutyric acid (GABA)A receptor). Juvenile female rats were reared in isolation or in groups of three for a 3-week period from weaning to mid-adolescence, after which all rats were group-reared for an additional 2 weeks. We then used dual immunohistochemical staining for c-Fos and tryptophan hydroxylase in the DR or single immunohistochemical staining for c-Fos in the basolateral amygdala. Isolation-reared rats, but not group-reared rats, injected with FG-7142 had increased c-Fos expression within the basolateral amygdala and in serotonergic neurons in the dorsal, ventrolateral, caudal and interfascicular parts of the DR relative to appropriate vehicle-injected control groups. These data suggest that post-weaning social isolation of female rats sensitizes a DR-basolateral amygdala system to stress-related stimuli, which may lead to an increased sensitivity to stress- and anxiety-related responses in adulthood. PMID:22297173

Lukkes, Jodi L.; Engelman, Glenn H.; Zelin, Naomi S.; Hale, Matthew W.; Lowry, Christopher A.



Perinatal ethinyl oestradiol alters mammary gland development in male and female Wistar rats.  


Increased attention is being paid to human mammary gland development because of concerns for environmental influences on puberty onset and breast cancer development. Studies in rodents have showed a variety of changes in the mammary glands after perinatal exposure to endocrine disrupting chemicals, indicating progressed development of mammary glands when exposed to oestrogens early in life. However, laboratories use different parameters to evaluate the development of mammary glands, making studies difficult to compare. Moreover, studies of whole mounts in Wistar rats are lacking. In the present study, Wistar rats were exposed to 0, 5, 15 or 50 ?g/kg of ethinyl oestradiol per day during gestation and lactation. A wide range of morphological parameters were evaluated in whole mounts of mammary glands from male and female offspring PD21-22. This study showed that in both male and female pre-pubertal Wistar rats, mammary gland development was accelerated after perinatal oestrogen exposure with increase in size, density and number of terminal end buds (TEBs). In female rats, the most sensitive parameters were the distance to the fifth gland, the relative growth towards the lymph node and the overall density. The sensitive endpoints in male rats were TEB numbers, both in the whole gland and in the zone C, the overall- and the highest density. The overall density was sensitive in both male and female rats and was considered a good representative of both branching and budding of the gland. The number of TEBs in zone C was representative of the number of TEBs in the whole gland. Further studies in older Wistar rats and with weak oestrogenic compounds could be performed to validate mammary gland examination as an endpoint in reproductive toxicity studies and to examine how early life environmental exposures may alter mammary gland development, disrupt lactation and alter susceptibility to breast cancer. PMID:22428746

Mandrup, K R; Hass, U; Christiansen, S; Boberg, J



Efficacy of Female Rat Models in Translational Cardiovascular Aging Research  

PubMed Central

Cardiovascular disease is the leading cause of death in women in the United States. Aging is a primary risk factor for the development of cardiovascular disease as well as cardiovascular-related morbidity and mortality. Aging is a universal process that all humans undergo; however, research in aging is limited by cost and time constraints. Therefore, most research in aging has been done in primates and rodents; however it is unknown how well the effects of aging in rat models translate into humans. To compound the complication of aging gender has also been indicated as a risk factor for various cardiovascular diseases. This review addresses the systemic pathophysiology of the cardiovascular system associated with aging and gender for aging research with regard to the applicability of rat derived data for translational application to human aging. PMID:25610649

Rice, K. M.; Fannin, J. C.; Gillette, C.; Blough, E. R.



Correlative Analysis of Behavioral and Physiological Concomitants of Labor in Pregnant Rats  

NASA Technical Reports Server (NTRS)

During parturition, rats exhibit characteristic behavioral expressions of labor. Lordosis contractions, consisting of an elongation of the dams body, are observed beginning several hours prior to neonate births, whereas vertical contractions, repeated rapid lifts of the abdomen, occur immediately preceding the birth of each neonate. We analyzed underlying changes in intrauterine pressure (IUP) using a telemetric sensor that we modified for use in freely-moving rats. This technique enabled us to correlate behavioral expressions of labor contractions with IUP. A small telemetric blood pressure sensor was fitted within a fluid-filled balloon, similar in size to a full term rat fetus. On Gestational day 19 of the rats' 22-day pregnancy, a unit was surgically implanted within the uterus. The dams were simultaneously videotaped, enabling us to directly correlate IUP signals with behavioral expressions of labor contractions. Earlier phases of labor, consisting predominantly of lordosis contractions were characterized by lower pressures relative to later phases during which higher pressures and vertical contractions were frequently observed.

Baer, L. A.; Wade, C. E.; Ronca, A. E.; Dalton, Bonnie (Technical Monitor)



Iron deficiency in the pregnant rat has differential effects on maternal and fetal copper levels  

Microsoft Academic Search

Iron deficiency during pregnancy causes problems both for the mother and fetus. Iron deficiency is known to have secondary effects on copper metabolism. In this study, we use a rat model to examine the effect of iron deficiency on copper levels in maternal and fetal tissue. We assess whether the effects of iron deficiency on copper metabolism are due to

Lorraine Gambling; Susan Dunford; Harry J. McArdle



Unmasking of surface negativity on day 6 pregnant rat uterine epithelial cells by trypsin and pronase.  


Cationic Ferritin and Ruthenium Red were used to label rat uterine luminal epithelial cells at estrus and 6th d of pregnancy. Labelling was heavy at estrus and light on 6th d. Trypsin and pronase reduced labelling at estrus and restored labelling at 6th d suggesting that negatively charged carbohydrates may become masked at the time of implantation. PMID:2475998

Hosie, M J; Murphy, C R



In utero phthalate effects in the female rat: a model for MRKH syndrome##  

EPA Science Inventory

Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome is characterized by uterine and vaginal canal aplasia in normal karyotype human females and is a syndrome with poorly defined etiology. Reproductive toxicity of phthalate esters (PEs) occurs in rat offspring exposed in utero, a phen...



EPA Science Inventory

The midcycle surge of luteinizing hormone (LH) from the pituitary provides the physiological trigger in the mammalian female for the process of ovulation. ccordingly, any agent that compromises the LH surge could function as a reproductive toxicant. ince ovariectomized (OVX) rats...



Technology Transfer Automated Retrieval System (TEKTRAN)

Soy isoflavones are becoming popular supplements among middle-aged women based on their potential protection against cancer and their use as alternative hormone replacement therapy. We investigated the effects of dietary soy isoflavones and age on early stage colon cancer in female rats. Young, matu...


Collagen deposition around polypropylene tapes implanted in the rectus fascia of female rats  

Microsoft Academic Search

ObjectiveImplantation of the mesh induces a foreign-body reaction followed by the development of connective tissue that may alter tape property. The aim of our study was to evaluate the deposition of collagen in the vicinity of monofilament tension-free vaginal tape (TVT; Ethicon Inc., Johnson & Johnson) and multifilament intravaginal slingplasty (IVS; Tyco Healthcare) polypropylene tapes implanted in female rats.

Micha? Bogusiewicz; Andrzej Wróbel; Katarzyna Jankiewicz; Aneta Adamiak; Pawe? Skorupski; Jacek Tomaszewski; Tomasz Rechberger



In Utero Phthalate Effects in the Female Rat: A Model for MRKH Syndrome  

EPA Science Inventory

Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome is characterized by uterine and vaginal canal aplasia in normal karyotype human females and is a syndrome with poorly define etiology. Reproductive toxicity of phthlate esters (PEs) occurs in rat offspring exposed in utero. a phenome...



EPA Science Inventory

The effect of the gamma isomer of 1,2,3,4,5,6-hexachlorocyclohexane (Y-HCH), lindane, on reproductive funtion in the female rat was examined in two experiments. n the first experiment, chronic treatment with 0, 5, 10, 20, and 40 mg/kg lindane delayed vaginal opening and disrupted...



EPA Science Inventory

Nonylphenol and Atrazine Induce Inverse Effects on Mammary Gland Development in Female Rats Exposed In Utero. HJ Moon1, SY Han1, CC Davis2, and SE Fenton2 1 Department of Toxicology, NITR, Korea FDA, 5Nokbun-Dong, Eunpyung-Gu, Seoul, Korea and 2 Reproductive Toxicology Divi...



EPA Science Inventory

Triadimefon is a widely used systemic fungicide, yet there is little published information on its effects in mammals. This study describes the effects of triadimefon in male and female rats using a functional observational battery (FOB), motor activity (measured in a figure-eight...


Peripubertal Administration of Icariin and Icaritin Advances Pubertal Development in Female Rats  

PubMed Central

Epimedii Herba is a traditional medicinal herb used in Korea and China and exerts estrogenic activity. In this study, we investigated the effect of peripubertal administration of Epimedii Herba on pubertal development in female rats using a modified protocol of the rodent 20-day pubertal female assay. Female Sprague-Dawley rats (21 days old after weaning, 10 rats per group) were divided into five groups: saline (Con), ethinyl estradiol (E2), Epimedii Herba ext (Ext), icariin (ICI), and icaritin (ICT), which were administered by oral gavage (E2 by subcutaneous injection) from postnatal day (PND) 21 through PND40. The time to vaginal opening (VO) was shorter for the Epimedii groups, particularly for the ICT group (p<0.05). Treatment with ICI and ICT significantly increased the duration of the estrus cycle (ICI, 2.78 days; ICT, 4.0 days; control, 1.78 days). Ovary weight was reduced by E2 treatment and increased by the Ext, ICI, and ICT treatments while the weight of the uterus and pituitary glands increased significantly only in the E2 and ICT groups. Although Epimedii Herba displayed relatively weak estrogenic activity, its repeated administration could affect pubertal development in female rats. PMID:24116294

Kang, Hyun Ku; Lee, Sang-Bum; Kwon, Hyosuk; Sung, Chung Ki; Park, Young In; Dong, Mi-Sook



Effects of altered food intake during pubertal development in male and female Wistar rats  

EPA Science Inventory

The U.S.EPA is currently validating assays that will be used in a Tier I Screening Battery to detect endocrine disrupting chemicals. A primary concern with the Protocols for the Assessment of Pubertal Development and Thyroid Function in Juvenile Male and Female Rats is that a non...


Neonatal Isolation Stress Potentiates Cocaine Seeking Behavior in Adult Male and Female Rats  

Microsoft Academic Search

Little is known with regard to how sex and stress might interact as vulnerability factors in cocaine abuse. In this study, we compared the effects of neonatal isolation stress on cocaine self-administration under extended access conditions and on subsequent responding in a cue-induced reinstatement paradigm in adult male and female rats. Pups from each litter were subjected to either neonatal

Wendy J Lynch; Lauren D Mangini; Jane R Taylor



17ß-Estradiol Is Necessary for Extinction of Cocaine Seeking in Female Rats  

ERIC Educational Resources Information Center

Human and preclinical models of addiction demonstrate that gonadal hormones modulate acquisition of drug seeking. Little is known, however, about the effects of these hormones on extinction of drug-seeking behavior. Here, we investigated how 17ß-estradiol (E[subscript 2]) affects expression and extinction of cocaine seeking in female rats. Using a…

Twining, Robert C.; Tuscher, Jennifer J.; Doncheck, Elizabeth M.; Frick, Karyn M.; Mueller, Devin



A possible physiological role of taurine in the adult female rat liver  

E-print Network

A possible physiological role of taurine in the adult female rat liver Y. PIERRE, Fernande. In agreement with previous results (Awapara, 1956), we noted that the tau- rine level in the liver of the adult as a concentration (ymoles/g of liver). Furthermore, we observ- ed a significant decrease of the taurine level

Paris-Sud XI, Université de



EPA Science Inventory

The Endocrine Profile of Intact Female Rats on the Day of Proestrus Following Exposure to Atrazine. RL Cooper, A Buckalew, SC Laws and TE Stoker Endocrinology Branch, RTD, NHEERL, ORD, U.S. EPA, RTP, NC, 27711. The chlorotriazine herbicide, atrazine, has been sho...


The Time of Prenatal Androgen Exposure Affects Development of Polycystic Ovary Syndrome-Like Phenotype in Adulthood in Female Rats  

PubMed Central

Background: Polycystic ovary syndrome (PCOS) is one of the most common reproductive disorders in women. Previous studies have shown that prenatal exposure of female fetuses to androgen can be considered an important factor in the development of PCOS. Objectives: In the present study we aimed to examine the effects of prenatal exposure of female rat fetuses to previously documented doses of testosterone on different embryonic days on the development of PCOS phenotype in adulthood. Materials and Methods: Pregnant rats were divided into four groups, experimental and control groups. Three mg of free testosterone was administered subcutaneously to experimental group 1 on gestational days 16-19, daily and 20 mg on day 20, to experimental group 2, and the controls received solvent at the same times. Female offspring of these mothers aged between 90-100 days were examined for development and function of the reproductive system. Independent-sample student t test was used to compare the results between the experimental groups and controls. Results: Anogenital distance (P < 0.001) and clitoris length were significantly increased in the offspring of both experimental groups (P < 0.001 and P < 0.05 respectively). Nipples were not formed in the offspring of experimental group 1, whereas in experimental group 2 the number of nipples was unchanged. Vaginal length was significantly decreased in the offspring of experimental group 1 (P < 0.001), whereas in experimental group 2, no significant difference was observed. In the offspring of experimental group 1, hormonal profiles did not differ, but in experimental group 2, levels of testosterone (P < 0.05) and LH (P < 0.01) were significantly increased, but estrogen (P < 0.05) and anti-Mullerian hormone levels (P < 0.001) were significantly decreased. A significant increase in the number of preantral and antral follicles was observed in the ovaries of offspring of experimental group 1 (P < 0.05); whereas there was no such a difference in experimental group 2. Conclusions: The time of prenatal exposure to androgens may have a significant role in the development of PCOS. Increased prenatal androgen levels are associated with hormonal changes and morphological disorders of the reproductive system. Therefore, avoiding exposure to androgen excess during critical periods of fetal development may prevent or reduce adulthood PCOS manifestations caused by prenatal excess androgen. PMID:24910644

Ramezani Tehrani, Fahimeh; Noroozzadeh, Mahsa; Zahediasl, Saleh; Piryaei, Abbas; Hashemi, Somayeh; Azizi, Fereidoun



Tripterygium glycosides impairs the proliferation of granulosa cells and decreases the reproductive outcomes in female rats.  


This study was carried out to investigate the impact of tripterygium glycosides (TGs) on ovarian function of female rats in vitro and in vivo. In vitro studies showed that TG induced cells decrease at G1 phase and inhibited cell proliferation in rat granulosa cells. In vivo, female rats were intragastrically administered with TG at the dose of 60 mg/kg/day for consecutive 50 days. TG caused a prolonged estrous cycle, and a significant reduction in ovarian index, serum E2 level, and numbers of secondary and antral follicles (p < 0.05) in these rats. A significant reduction of viable embryos was demonstrated in TG-treated female rats after mating (p < 0.01). Further, we observed observed the reduced expression level of TGF-?1 after TG treatment in vitro and in vivo. Moreover, the expression of Smad2 and AKT was also decreased after TG treatment. These results suggest that TG can impair ovarian function through Smads-mediated TGF-?1 signal pathway. PMID:24831781

Su, Jing; Cheng, Jie; Sun, Hai-Xiang; Diao, Zhen-Yu; Zhen, Xin; Yang, Jun; Ding, Li-Jun; Hu, Ya-Li



Effect of methamphetamine on cognitive functions of adult female rats prenatally exposed to the same drug.  


The aim of this study was to investigate the effect of prenatal methamphetamine (MA) exposure and application of the same drug in adulthood on cognitive functions of adult female rats. Animals were prenatally exposed to MA (5 mg/kg) or saline (control group). The cognitive function was tested as ability of spatial learning in the Morris Water Maze (MWM). Each day of the experiment animals received an injection of MA (1 mg/kg) or saline. Our results demonstrated that prenatal MA exposure did not affect the latency to reach the hidden platform or the distance traveled during the Place Navigation Test; however, the speed of swimming was increased in prenatally MA-exposed rats compared to controls regardless of the treatment in adulthood. MA treatment in adulthood increased the latency and distance when compared to controls regardless of the prenatal exposure. Neither prenatal exposure, nor treatment in adulthood affected memory retrieval. As far as the estrous cycle is concerned, our results showed that prenatally MA-exposed females in proestrus/estrus swam faster than females in diestrus. This effect of estrous cycle was not apparent in control females. In conclusion, our results indicate that postnatal, but not prenatal exposure to MA affects learning of adult female rats. PMID:24329708

Macúchová, E; Nohejlová-Deykun, K; Slamberová, R



The role of adrenoceptors in the central nervous system in male and female rat sexual behavior.  


Three different phases can be distinguished in rats' sexual cycle, the introductory (precopulatory), the copulatory and the executive (ejaculatory) phases. In this review, a new analysis of existing pharmacological data is made, both in male and female rats, in which the different aspects of sexual behavior are taken into account. An effort is made to distinguish pharmacological effects on sexual behavior from a possible physiological role of noradrenaline. In addition, new data on the role of ?2-adrenoceptors on female sexual behavior is presented. The new analysis suggests that noradrenaline has a stimulatory role on the executive phase of male sexual behavior, while the introductory and copulatory phases remain unaffected. Adrenoceptors play a role in the regulation of sexual behavior in the medial preoptic area and the lateral septum. In female rats, noradrenaline also does not play a vital role in the introductory phase. Only the lordosis behavior of the copulatory phase is sometimes affected by adrenergic agents, but only under a certain hormonal condition. The medial preoptic area, the ventromedial nucleus, the arcuate ventromedial nucleus and median eminence are involved in the regulation of female sexual behavior. The new data suggest that ?2-adrenoceptors play no major role on any indices of female sexual behavior. PMID:25218984

Snoeren, Eelke M S



Efficacy of antipsychotics to reverse phencyclidine-induced social interaction deficits in female rats--a preliminary investigation.  


Sub-chronic phencyclidine (PCP) treatment mimics certain aspects of schizophrenia symptomology in rats. However, there is a marked lack of attempts to model negative symptomology such as social behaviour deficits in female rats. This study was conducted to assess whether sub-chronic PCP treatment produces social interaction deficits in female rats and to ascertain if these deficits can be reversed by either typical (haloperidol) or atypical (clozapine and ziprasidone) antipsychotics. PMID:18037171

Snigdha, Shikha; Neill, Joanna C



Adolescent MDMA exposure diminishes the physiological and neurotoxic consequences of an MDMA binge in female rats.  


Intermittent MDMA pretreatment blocked the reductions in serotonin transporter (SERT) binding induced by an MDMA binge in a prior study in adolescent male rats. The objective of this investigation was to determine if the physiological, behavioral, and neurochemical responses to MDMA are sexually dimorphic. Female Sprague-Dawley rats received MDMA (10?mg/kg?×?2) or Saline on every fifth day from postnatal day (PD) 35-60 and an MDMA binge (5?mg/kg?×?4) on PD 67. The MDMA binge induced a pronounced temperature dysregulation in MDMA-naïve, but not MDMA-pretreated, groups. Similarly, MDMA-pretreated animals were resistant to the binge-induced SERT reductions, especially in the hippocampus. Motor activity at PD 68 was not reduced by the binge, unlike the responses found in males. These results show that female rats differ from males in their responses to an MDMA binge but are similar with respect to preconditioning from prior MDMA exposure. PMID:24752593

Piper, Brian J; Henderson, Christina S; Meyer, Jerrold S



The effect of alcohol on the bone growth spurt of rats at a time equivalent to adolescent females  

E-print Network

The objective of this study is to determine the effect of long-term alcohol consumption on the growth spurt in adolescent rats. Female Sprague-Dawley rats were fed one of three diets (alcohol, pair-fed or chow) for 3 months. The rats were sacrificed...

Chaffin, Catherine Lee



In vitro metabolism of putrescine by diamine oxidase in tissues of the pregnant rat  

Microsoft Academic Search

The metabolism of14C-putrescine by diamine oxidase was tested on the 19th day of pregnancy in different organs of rats. The highest turnover was found in maternal placenta and uterus where 94% of the reaction product was identified as?1-pyrroline. Considerable deamination rates were also observed in ovary, liver and fetal placenta where, however, ?-aminobutyric acid was the predominant product. In the

Anne-Charlotte Andersson; Stig Henningsson



Maternal and developmental toxicity evaluation of melatonin administered orally to pregnant Sprague-Dawley rats  

Microsoft Academic Search

Melatonin (MEL) is a widely used, over-the-counter sleep aid, and it has putative contraceptive, antioxidant, antiaging, and anticancer effects. The developmental toxicity potential for re- peated oral doses of MEL had not previously been evaluated. In the present studies, time-mated, Sprague-Dawley-derived (CDt) rats were administered MEL or vehicle by gavage on gestation days (gd) 6 -19. MEL-treated groups received 1-,

G. Jahnke; M. Marr; C. Myers; R. Wilson; G. Travlos; C. Price



Protective effect of dienogest on chemotherapy-induced reduced fertility in female rats.  


Reduced fertility is one of the main long-term consequences of chemotherapy given for lymphoma, leukemia, and other malignancies in young women. We examined with a female rat model whether and how dienogest, a fourth-generation progestin, modulates reduced fertility following exposure to gonadotoxic chemotherapy. Female rats were administered cyclophosphamide with or without GnRH agonist and different concentrations of dienogest for 20days. Animals were sacrificed on Day 29, and the numbers of follicle at primordial, preantral and antral stage in the ovaries were counted histologically. Rats treated with sterile saline solution (as control), cyclophosphamide, cyclophosphamide plus GnRH agonist, and cyclophosphamide plus dienogest were also mated with male rats to evaluate their fertility and pregnancy outcomes. Cyclophosphamide significantly reduced the number of primordial follicles, whereas dienogest suppressed depletion of primordial follicle pool induced by chemotherapy. Although the rats exposed to cyclophosphamide alone failed to deliver live births, co-treatment with dienogest improved the pregnancy outcomes of treated rats. The protective effect of dienogest on chemotherapy-induced ovarian damage and reduced fertility was comparable to that of GnRH agonist. The present results suggest that the co-administration of dienogest and chemotherapy may be a useful strategy in preserving ovarian function and fertility in premenopausal women facing gonadotoxic chemotherapy. PMID:25449767

Tsuyoshi, Hideaki; Orisaka, Makoto; Fukuda, Shin; Hattori, Katsushige; Tsang, Benjamin K; Yoshida, Yoshio



HIV-1 transgenic female rat: synaptodendritic alterations of medium spiny neurons in the nucleus accumbens.  


HIV-1 associated neurocognitive deficits are increasing in prevalence, although the neuronal basis for these deficits is unclear. HIV-1 Tg rats constitutively express 7 of 9 HIV-associated proteins, and may be useful for studying the neuropathological substrates of HIV-1 associated neurocognitive disorders (HAND). In this study, adult female HIV-1 Tg rats and F344 control rats had similar growth rates, estrous cyclicity and startle reflex inhibition to a visual prepulse stimulus. Medium spiny neurons (MSNs) in the nucleus accumbens (NAcc) were ballistically-labeled utilizing the indocarbocyanine dye DiI. The branching complexity of MSNs in the NAcc was significantly decreased in HIV-1 Tg rats, relative to controls; moreover, the shorter length and decreased volume of dendritic spines, but unchanged head diameter, in HIV-1 Tg rats suggested a reduction of longer spines and an increase in shorter, less projected spines, indicating a population shift to a more immature spine phenotype. Collectively, these results from HIV-1 Tg female rats indicated significant synaptodendritic alterations of MSNs in the NAcc occur as a consequence of chronic, low-level, exposure to HIV-1 associated proteins. PMID:25037595

Roscoe, Robert F; Mactutus, Charles F; Booze, Rosemarie M



Female mice and rats exhibit species-specific metabolic and behavioral responses to ovariectomy  

PubMed Central

Ovariectomy (OVX) leads to hyperphagia and weight gain in rats, which can be prevented by estradiol (E2) replacement; however, the role of endogenous E2 on feeding and energy homeostasis in female mice has not been well characterized. The primary goal of this study was to assess the relative contribution of increased energy intake and decreased energy expenditure to OVX-induced weight gain in female rats and mice. OVX led to hyperphagia in rats, but did not produce daily, nor cumulative, hyperphagia in mice. OVX decreased mass-specific metabolic rate in mice, but not in rats. OVX decreased home cage locomotor activity in both species. Pair-feeding attenuated OVX-induced weight gain in rats and produced both short- and long-term changes in expression of key hypothalamic genes involved in food intake and energy homeostasis, i.e., the anorexigenic neuropeptide pro-opiomelanocortin (POMC) and the orexigenic neuropeptides: melanin-concentrating hormone (MCH) and agouti-related peptide (AgRP). No differences in hypothalamic gene expression were observed between OVX’d and sham mice. The results suggest that OVX-induced weight gain is mediated by hyperphagia and reduced locomotor activity in rats, but that in mice, it is primarily mediated by reduced locomotor activity and metabolic rate. PMID:20067798

Witte, Michelina Messina; Resuehr, David; Chandler, Ashley R.; Mehle, Ashlee K.; Overton, J. Michael



Stimulation of contraction of pregnant rat uterus in vitro by non-dechlorinated and microbially dechlorinated mixtures of polychlorinated biphenyls.  

PubMed Central

A previous study of six polychlorinated biphenyl (PCB) congeners showed that PCBs with four or fewer chlorines and ortho substitution stimulate uterine contraction frequency in vitro, whereas congeners with a greater number of chlorines or non-ortho substitution are inactive in vitro. We tested the hypothesis that PCB mixtures stimulate uterine contractions in a manner inversely related to the degree of chlorination and the presence of chlorines in the ortho- position of the biphenyl constituents of the mixtures. Uterine strips from pregnant rats were suspended in standard muscle baths and analyzed for changes in isometric contractions in response to in vitro exposure to commercial PCB mixtures (Aroclors) and their dechlorinated products after microbial degradation. The PCB mixtures Aroclor 1242, 1248, and 1254 significantly stimulated uterine contraction frequency, and the least chlorinated mixture, Aroclor 1242, was the most potent stimulant. Microbes from Hudson River sediment dechlorinated Aroclor 1242 and Aroclor 1254 under reducing conditions to produce mixtures with an increased proportion of ortho-substituted congeners with one or two chlorine substitutions. The PCB mixtures that had undergone microbial reductive dechlorination stimulated uterine contraction frequency to a significantly greater extent than the parent mixtures. These results show that increased uterotonic activity was associated with decreased chlorination and increased ortho substitution of the biphenyl constituents of the mixtures. PMID:11333189

Bae, J; Mousa, M A; Quensen, J F; Boyd, S A; Loch-Caruso, R



The effect of pregnant mares serum gonadotrophin on the response of DMBA induced rat mammary tumours to tamoxifen or oestrogen.  


Ovariectomized and intact rats bearing mammary tumours, induced with 7,12-dimethylbenz(a)anthracene, were treated with diethylstilboestrol (DES), tamoxifen and pregnant mares serum gonadotrophin (PMSG) alone or in various combinations. In ovariectomized animals, PMSG (100 iu daily) alone, or with DES (50 micrograms) or tamoxifen (50 micrograms), slowed tumour regression. Mean tumour volume after 5 weeks was larger than control (P less than 0.05) in animals treated with PMSG + DES but not with PMSG or PMSG + tamoxifen. In intact animals, PMSG (200 iu bd, but not 2 or 20 iu bd) slowed tumour growth (P less than 0.05) and PMSG (2 or 200 iu bd) reversed the tumour inhibiting effect of tamoxifen (200 micrograms). PMSG (2 iu bd), in contrast to 20 and 200 iu doses, showed no evidence of oestrogen stimulation. It is suggested that the reversal of the tumour inhibiting effect of tamoxifen by this low dose of PMSG may be of relevance to failure of tamoxifen treatment and to 'tamoxifen flare'. PMID:2517258

Clark, E R; Robinson, S P; Whitaker, E M; Zoltowski, J A



Fetal growth and 1,25-dihydroxyvitamin D3 injections into thyroparathyroidectomized pregnant rats  

E-print Network

/kg of body weight) and compared with untreated TPTX mothers or sham-operated normal females. The treated (+ 1.6- 2.0 g) occurred at term with doses ranging from 0.05 to 0.25 [Lg/kg of body weight ; higher calcium and phosphate levels were unchanged, and a slight decrease in fetal weight (! 0.8 g) was observed

Paris-Sud XI, Université de


The response of Dahl salt-sensitive and salt-resistant female rats to a space flight model  

NASA Technical Reports Server (NTRS)

Vitamin D metabolism in the Dahl salt-sensitive (S) rat, a model of salt-induced hypertension, differs from that in the Dahl salt-resistant (R) rat. We have tested the hypothesis that differences in vitamin D metabolism would render the Dahl S rat more susceptible than the Dahl R rat to the effects of a space flight model. Dahl female rats were tail suspended (hind limb unloaded) for 28 days, while fed a low salt (3 g/kg sodium chloride) diet. Plasma 25-OHD concentrations of S rats were significantly lower than that of R rats. Plasma 1,25-(OH)2D concentration was 50% lower in unloaded than in loaded S rats, but was unaffected in unloaded R rats. The left soleus muscle weight and breaking strength of the left femur (torsion test) were 50% and 25% lower in unloaded than in loaded S and R rats. The mineral content of the left femur, however, was significantly lower (by 11%) only in unloaded S rats. We conclude that female S rats are more vulnerable than female R rats to decreases in plasma 1,25-(OH)2D concentration and femur mineral content during hind limb unloading, but equally vulnerable to muscle atrophy and reduced breaking strength of the femur.

Thierry-Palmer, Myrtle; Cephas, Stacy; Cleek, Tammy; Sayavongsa, Phouyong; Arnaud, Sara B.



Female Infertility  


Infertility is a term doctors use if a woman hasn't been able to get pregnant after ... woman keeps having miscarriages, it is also called infertility. Female infertility can result from physical problems, hormone ...


Antifertility effects of Pouzolzia mixta in female Wistar rats.  


The continued use of plants by women to prevent pregnancy suggests there are plants out there with potential use as contraceptives. In Zimbabwe, Pouzolzia mixta is used as a "morning after" contraceptive, thus it may possess postcoital antifertility activity. To test contraceptive activity, animals (n=8/group) were orally pretreated with aqueous (AqPM) or ethanolic (EtPM) extract of P. mixta at 300mg/kg b.wt for 7 days followed by mating with continued treatment for 10 days post-conception. To test for postcoital activity, treatment was initiated on day-1 of pregnancy and continued for 10 days. Laparotomy was performed and implantations counted. For estrogenic activity, immature ovariectomised rats were treated for 7 days after which vaginal opening and uterine weights were determined. In vitro oxytocic effects were performed using uterine tissue in an organ bath with De Jalon's solution. Acetylcholine (Ach) was the positive control. Results showed modest contraceptive activity with EtPM more effective in inhibiting fertility compared to AqPM (37.5% vs 25%) with a similar trend for antiimplantation effects (31% vs 19%). There was potent postcoital antifertility effects with AqPM more effective in inhibiting implantation (94.6% vs 86%) and fertility (87.5% vs 75%) compared to EtPM. Immature rat bioassay for estrogenic activity demonstrated pronounced estrogenic activity by both extracts. Oxytocic effects at 400ng/ml were more pronounced for the AqPM (92% of 100ng/ml Ach) than EtPM (25% of 100ng/ml Ach). Findings demonstrate the antifertility effects of aqueous and ethanolic extracts of P. mixta. The antifertility effects may be attributed to antiimplantation, estrogenic and oxytocic effects of the plant extracts. PMID:24146484

Sewani-Rusike, Constance Rufaro



Prenatal LPS-exposure - a neurodevelopmental rat model of schizophrenia - differentially affects cognitive functions, myelination and parvalbumin expression in male and female offspring.  


Maternal infection during pregnancy increases the risk for the offspring to develop schizophrenia. Gender differences can be seen in various features of the illness and sex steroid hormones (e.g. estrogen) have strongly been implicated in the disease pathology. In the present study, we evaluated sex differences in the effects of prenatal exposure to a bacterial endotoxin (lipopolysaccharide, LPS) in rats. Pregnant dams received LPS-injections (100?g/kg) at gestational day 15 and 16. The offspring was then tested for prepulse inhibition (PPI), locomotor activity, anxiety-like behavior and object recognition memory at various developmental time points. At postnatal day (PD) 33 and 60, prenatally LPS-exposed rats showed locomotor hyperactivity which was similar in male and female offspring. Moreover, prenatal LPS-treatment caused PPI deficits in pubertal (PD45) and adult (PD90) males while PPI impairments were found only at PD45 in prenatally LPS-treated females. Following prenatal LPS-administration, recognition memory for objects was impaired in both sexes with males being more severely affected. Additionally, we assessed prenatal infection-induced alterations of parvalbumin (Parv) expression and myelin fiber density. Male offspring born to LPS-challenged mothers showed decreased myelination in cortical and limbic brain regions as well as reduced numbers of Parv-expressing cells in the medial prefrontal cortex (mPFC), hippocampus and entorhinal cortex. In contrast, LPS-exposed female rats showed only a modest decrease in myelination and Parv immunoreactivity. Collectively, our data indicate that some of the prenatal immune activation effects are sex dependent and further strengthen the importance of taking into account gender differences in animal models of schizophrenia. PMID:25455585

Wischhof, Lena; Irrsack, Ellen; Osorio, Carmen; Koch, Michael



Curcumin improves spatial memory and decreases oxidative damage in aged female rats.  


Aging induced cognitive impairment has been well documented for many years and several antioxidant strategies have been developed against this impairment. Curcumin is the active component of curcuma longa and has shown antioxidant, antiinflamatory and neuroprotective properties. We hypothesized that curcumin would have an influence on cognitive functions in aged female rats. The purpose of the present study was to investigate the effects of curcumin supplementation on cognitive impairment evaluated by Morris water maze (MWM) as well as the oxidative stress induced by aging in female rats. Rats were randomly divided into either control or curcumin-supplemented groups. Curcumin or vehicle (corn oil) were given once daily for a period of 12 days, beginning 7 days prior to and 5 days during the behavioral tests. Behavioral assessment was performed in MWM. At the end of the behavioral test, blood samples and brain tissues were taken for the analysis of malondialdeyde (MDA), protein carbonyl and glutathione levels. During the training session, curcumin supplementation decreased latency to reach to the platform and the total distance traveled. During the probe trial, curcumin supplementation increased the number of platform crossings. In addition to the behavioral testing, biochemical results showed that MDA levels decreased in brain tissue by curcumin supplementation. It may be concluded that, curcumin supplementation improves cognitive functions by decreasing the lipid peroxidation in brain tissue of aged female rats. PMID:23609199

Belviranl?, Muaz; Okudan, Nilsel; Atal?k, K?smet Esra Nurullaho?lu; Öz, Mehmet



Chronic scream sound exposure alters memory and monoamine levels in female rat brain.  


Chronic scream sound alters the cognitive performance of male rats and their brain monoamine levels, these stress-induced alterations are sexually dimorphic. To determine the effects of sound stress on female rats, we examined their serum corticosterone levels and their adrenal, splenic, and thymic weights, their cognitive performance and the levels of monoamine neurotransmitters and their metabolites in the brain. Adult female Sprague-Dawley rats, with and without exposure to scream sound (4h/day for 21 day) were tested for spatial learning and memory using a Morris water maze. Stress decreased serum corticosterone levels, as well as splenic and adrenal weight. It also impaired spatial memory but did not affect the learning ability. Monoamines and metabolites were measured in the prefrontal cortex (PFC), striatum, hypothalamus, and hippocampus. The dopamine (DA) levels in the PFC decreased but the homovanillic acid/DA ratio increased. The decreased DA and the increased 5-hydroxyindoleacetic acid (5-HIAA) levels were observed in the striatum. Only the 5-HIAA level increased in the hypothalamus. In the hippocampus, stress did not affect the levels of monoamines and metabolites. The results suggest that scream sound stress influences most physiologic parameters, memory, and the levels of monoamine neurotransmitter and their metabolites in female rats. PMID:24952268

Hu, Lili; Zhao, Xiaoge; Yang, Juan; Wang, Lumin; Yang, Yang; Song, Tusheng; Huang, Chen



Oxidative Stress Contributes to Soluble Fms-Like Tyrosine Kinase-1 Induced Vascular Dysfunction in Pregnant Rats  

PubMed Central

BACKGROUND Recent evidence indicates that both increased oxidative stress and an altered balance between pro- and anti-angiogenic factors such as vascular-endothelial growth factor (VEGF) and the soluble VEGF receptor (sFlt-1) contribute to endothelial dysfunction in preeclampsia. We hypothesized that chronic infusion of sFlt-1 to mimic the increase observed in preeclamptic patients would reduce plasma VEGF concentrations, increase blood pressure (BP) and vascular superoxide levels, and cause endothelial dysfunction in the pregnant rat. METHODS Recombinant sFlt-1 was infused (500 ng/h) during days 13–18 of pregnancy. BP, fetal and placental weight, oxidative stress and vessel vasorelaxation were determined on day 18 of pregnancy. RESULTS Plasma sFlt-1 concentrations (299 ± 33 vs. 100 ± 16 pg/ml; P < 0.01) and BP (117 ± 6 vs. 98 ± 4 mm Hg; P < 0.01) were increased, while plasma-free VEGF concentrations (570 ± 77 vs. 780 ± 48 pg/ml; P < 0.01) were decreased when compared to vehicle infused dams. sFlt-1 rats had smaller fetuses (1.3 ± 0.03 vs. 1.5 ± 0.04 g, P < 0.01) and placentas (0.41 ± 0.01 vs. 0.47 ± 0.02 g; P < 0.05). Placental (180 ± 66 vs. 24 ± 2.3 RLU/min/mg; P < 0.05) and vascular (34 ± 8 vs. 12 ± 5 RLU/min/mg; P < 0.05) superoxide production was increased in the sFlt-1 compared to vehicle infused rats. Vasorelaxation to acetylcholine (Ach) and sodium nitroprusside (SNP) were both decreased (P < 0.05) in the sFlt-1 infusion group compared to the vehicle and this decrease was attenuated (P < 0.05) by the superoxide scavenger Tiron. CONCLUSION These data indicate elevated maternal sFlt-1 and decreased VEGF concentrations results in increased oxidative stress that contributes to vascular dysfunction during pregnancy. PMID:19265787

Bridges, Jason P.; Gilbert, Jeffrey S.; Colson, Drew; Gilbert, Sara A.; Dukes, Matthew P.; Ryan, Michael J.; Granger, Joey P.



Effect of chronic infusion of olanzapine and clozapine on food intake and body weight gain in male and female rats  

Microsoft Academic Search

Many antipsychotics cause weight gain in humans, but usually not in rats, when injected once or twice daily. Since blood antipsychotic half-lives are short in rats, compared to humans, chronic administration by constant infusion may be necessary to see consistent weight gain in rats. Male and female rats were implanted with mini-pumps for constant infusion of olanzapine (5 mg\\/kg\\/day), clozapine (10 mg\\/kg\\/day)

SuJean Choi; Briana DiSilvio; JayLynn Unangst; John D. Fernstrom



Raloxifene Prevents Skeletal Fragility in Adult Female Zucker Diabetic Sprague-Dawley Rats  

PubMed Central

Fracture risk in type 2 diabetes is increased despite normal or high bone mineral density, implicating poor bone quality as a risk factor. Raloxifene improves bone material and mechanical properties independent of bone mineral density. This study aimed to determine if raloxifene prevents the negative effects of diabetes on skeletal fragility in diabetes-prone rats. Adult Zucker Diabetic Sprague-Dawley (ZDSD) female rats (20-week-old, n?=?24) were fed a diabetogenic high-fat diet and were randomized to receive daily subcutaneous injections of raloxifene or vehicle for 12 weeks. Blood glucose was measured weekly and glycated hemoglobin was measured at baseline and 12 weeks. At sacrifice, femora and lumbar vertebrae were harvested for imaging and mechanical testing. Raloxifene-treated rats had a lower incidence of type 2 diabetes compared with vehicle-treated rats. In addition, raloxifene-treated rats had blood glucose levels significantly lower than both diabetic vehicle-treated rats as well as vehicle-treated rats that did not become diabetic. Femoral toughness was greater in raloxifene-treated rats compared with both diabetic and non-diabetic vehicle-treated ZDSD rats, due to greater energy absorption in the post-yield region of the stress-strain curve. Similar differences between groups were observed for the structural (extrinsic) mechanical properties of energy-to-failure, post-yield energy-to-failure, and post-yield displacement. These results show that raloxifene is beneficial in preventing the onset of diabetes and improving bone material properties in the diabetes-prone ZDSD rat. This presents unique therapeutic potential for raloxifene in preserving bone quality in diabetes as well as in diabetes prevention, if these results can be supported by future experimental and clinical studies. PMID:25243714

Hill Gallant, Kathleen M.; Gallant, Maxime A.; Brown, Drew M.; Sato, Amy Y.; Williams, Justin N.; Burr, David B.



Effects of high frequency noise on female rat's multi-organ histology.  


To investigate the pathological damage of high-frequency stable noise exposure on the brain, heart, liver, and spleen of female rat's. Controlled animal intervention study. Twenty female Sprague-Dawley rats were randomly divided into experimental and control groups with 10 rats in each group. Rats in the experimental group were exposed to continuous high-frequency stable noise for 2 weeks (3 h/day)followed by the pathological damages in the rat's brain, heart, liver, and spleen were compared with those of the control group. After 2 weeks' continuous exposure to high-frequency stable noise, compared with the control group, the most prominent histopathologic changes in the brain tissue structures of the experimental group included loose disorder, hyperemia, edema, blood vessels expand, glial cell hyperplasia, mild atypia in some areas (hyperchromatic nuclei, irregular karyotype), and no degeneration and necrosis. There were dilatation and congestion of central vein, hepatic sinus, and interlobular veins of liver tissue. The structure of hepatic lobule was destroyed by inflammatory cell infiltration, as well as lymphoid nodule formation. There was hyperemia in spleen, but the structure was clear. There was extravasated blood, and the splenic sinuses were highly expanded by a blood clot. Hyperplasias of the lymphoid of white pulp were also active. There was dilation and congestion in myocardial interstitial vascular, and there was mild degeneration and hyperemia in myocardial cells. No hemorrhage and myocardial necrosis were observed. High-frequency stable noise can cause pathological damage in brain, liver, spleen, and heart tissues of female rat at a various degree. PMID:25033787

Xue, Laijun; Zhang, Dajun; Wang, Ting; Shou, Xi



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


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

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



Effect of triptolide on reproduction of female lesser bandicoot rat, Bandicota bengalensis.  


Triptolide has been reported to cause antifertility in male rats and mice. However, studies on female rats have been limited. Present study was aimed to evaluate the effects of triptolide on reproduction of wild female rodent pest species, Bandicota bengalensis. Feeding of bait containing 0.1, 0.15 and 0.2% triptolide for a period of 15 days in bi-choice resulted in per day ingestion of 17.37, 23.54 and 27.49?mg/kg body weight of triptolide, respectively. Examination of vaginal smear of all the rats revealed a significant (p???0.05) increase in duration of estrous cycle due to increase in durations of metestrous and diestrous stages in rats of treated groups. Autopsy of rats after 15 and 30 days of treatment withdrawal revealed significant (p???0.05) reduction in weights of uterus and ovaries, non-significant reduction in weights of liver and levels of estradiol and progesterone and significant (p???0.05) reduction in levels of urea and BUN and increase in levels of plasma proteins, ALT, AST, ALP, ACP and LDH in rats of treated groups compared to untreated group. There was no significant (p???0.05) effect of treatment on body weight. Triptolide treatment affected the histomorphology of uterus by causing a decrease in lumen and columnar cell height and number of uterine glands and ovary by increasing the number of atretic follicles and decreasing the number of developing follicles. The present study suggests triptolide to be a strong candidate affecting reproduction of female B. bengalensis. PMID:24490988

Dhar, Parul; Singla, Neena



Effects of Hypergravity Exposure On Plasma Oxytocin Concentrations In Pregnant and Lactating Rat Dams  

NASA Technical Reports Server (NTRS)

Rat dams and offspring were exposed to 1.5-g, 1.75-g or 2.0-g hypergravity (hg) from Gestational day (G) 11 until Postnatal day (P) 10. To ascertain the role of maternal factors in reduced postnatal body weights of offspring developed in hg, the dams' lactational hormones were measured. Oxytocin (OT), the major hormone responsible for milk ejection, was reduced in hg dams whereas prolactin (Prl), involved in milk production, was unchanged. Video analyses of nursing behavior revealed that hg dams spent more time nursing relative to 1-g controls. We hypothesized impaired milk transfer from dam to pup, however pup body weight gains following a discrete suckling episode were comparable across conditions. Changes in lactational hormones and nursing behavior by dams exposed to hg do not account for reduced body masses of their offspring.

Baer, Lisa A.; Wade, Charles E.; Ronca, April E.; Dalton, Bonnie (Technical Monitor)



Effect of valproic acid on /sup 65/Zn distribution in the pregnant rat  

SciTech Connect

The effect of valproic acid on the distribution of gavaged /sup 65/Zn in maternal and embryonic tissue of Sprague-Dawley rats was examined 24 h after gavaging of the drug on d 13 of pregnancy. Valproic acid treatment resulted in a significantly higher retention of /sup 65/Zn in maternal liver and lower amounts in uterus, placenta and embryos than in controls. Compared to controls, gel chromatography of maternal liver from valproic acid-treated dams showed higher /sup 65/Zn counts associated with a protein peak of molecular weight of 6,500, the approximate molecular weight of the Zn-binding protein metallothionein. These results support the idea that the teratogenicity of valproic acid is in part due to an induction of embryonic Zn deficiency secondary to a drug-induced sequestering of Zn into maternal liver that results in a decrease in maternal plasma Zn and subsequent reduction in embryonic Zn uptake.

Keen, C.L.; Peters, J.M.; Hurley, L.S.



Perinatal salt restriction: a new pathway to programming adiposity indices in adult female Wistar rats.  


Low birth weight has been associated with increased obesity in adulthood. It has been shown that dietary salt restriction during intrauterine life induces low birth weight and insulin resistance in adult Wistar rats. The present study had a two-fold objective: to evaluate the effects that low salt intake during pregnancy and lactation has on the amount and distribution of adipose tissue; and to determine whether the phenotypic changes in fat mass in this model are associated with alterations in the activity of the renin-angiotensin system. Maternal salt restriction was found to reduce birth weight in male and female offspring. In adulthood, the female offspring of dams fed the low-salt diet presented higher adiposity indices than those seen in the offspring of dams fed a normal-salt diet. This was attributed to the fact that adipose tissue mass (retroperitoneal but not gonadal, mesenteric or inguinal) was greater in those rats than in the offspring of dams fed a normal diet. The adult offspring of dams fed the low-salt diet, compared to those dams fed a normal-salt diet, presented the following: plasma leptin levels higher in males and lower in females; plasma renin activity higher in males but not in females; and no differences in body weight, mean arterial blood pressure or serum angiotensin-converting enzyme activity. Therefore, low salt intake during pregnancy might lead to the programming of obesity in adult female offspring. PMID:18289603

Lopes, Karen L; Furukawa, Luzia N S; de Oliveira, Ivone B; Dolnikoff, Miriam S; Heimann, Joel C



Prenatal Bystander Stress Alters Brain, Behavior, and the Epigenome of Developing Rat Offspring  

Microsoft Academic Search

The prenatal environment, including prenatal stress, has been extensively studied in laboratory animals and humans. However, studies of the prenatal environment usually directly stress pregnant females, but stress may come ‘indirectly’, through stress to a cage-mate. The current study used indirect prenatal bystander stress and investigated the effects on the gross morphology, pre-weaning behavior, and epigenome of rat offspring. Pregnant

Richelle Mychasiuk; Nichole Schmold; Slava Ilnytskyy; Olga Kovalchuk; Bryan Kolb; Robbin Gibb



The effects of the aromatase inhibitor fadrozole hydrochloride on fetuses and uteri in late pregnant rats.  


It is well known that progesterone and estrogen are essential hormones for maintaining pregnancy in most mammals. Some specific roles of progesterone for the maintenance of pregnancy have been clarified, but the role of estrogen is not well known. This study examines the effects of the aromatase inhibitor, fadrozole hydrochloride (Fad), on fetuses, uterine physical properties and the mRNA expression of the uterine enzymes that are related to collagen metabolism during late pregnancy in rats. Continuous s.c. infusion with 300 micro g/day Fad from day 14 of pregnancy (day 1=the day of sperm detection) reduced the concentration of plasma estradiol-17beta (E(2)), and did not change that of plasma progesterone, compared with controls. The treatment increased the intrauterine pressure and reduced the size and compliance of the uterine tissue framework. It also caused injuries (hematomata on the extremities) in about one-quarter of fetuses by day 20. The collagen content of the uterine ampullae was not changed by the treatment. Uterine mRNA expressions of matrix metalloproteinase-1 (MMP-1), which degrades collagens, and of lysyl oxidase (LO), which is necessary for the formation of intra- and inter-molecular cross-links of collagen, were examined by quantitative RT-PCR. The treatment with Fad had no effect on the expression of MMP-1 mRNA and increased that of LO mRNA. Daily s.c. injection with 0.2 micro g E(2) restored the changes in uterine physical properties and the mRNA expression of LO caused by the Fad treatment, and prevented fetal injury, indicating that the influences of Fad treatment are due to estrogen deficiency but not to toxicological effects of Fad. These results imply that estrogen deficiency during late pregnancy in rats obstructs development of the uterine tissue framework so as to cause fetal injury. It is possible that an increase in the uterine expression of LO gene may be involved in this obstruction. PMID:14765986

Tamada, H; Shimizu, Y; Inaba, T; Kawate, N; Sawada, T



Oxytocin receptors differentially signal via Gq and Gi proteins in pregnant and nonpregnant rat uterine myocytes: implications for myometrial contractility.  


Oxytocin (OT) receptors are important regulators of myometrial contractility. By using the activity of large conductance Ca2+-activated K+ (BKCa) channels as readout, we analyzed OT signaling in cells from nonpregnant (NPM) and pregnant (PM) rat myometrium in detail. In nystatin-perforated whole-cell patches from NPM cells, which leave the intracellular integrity intact, OT transiently increased BKCa-mediated outward currents (Iout). This OT-evoked Iout was caused by the Ca2+ transients in response to the Gq/11-mediated activation of phospholipase C and was inhibited by activation of protein kinase A (PKA). In an open-access whole-cell patch (OAP), the OT-induced transient rise in Iout was disrupted whereas the regulation of BKCa by the cAMP/PKA cascade remained intact. OT counteracted the isoprenaline, i.e. the beta-adrenoceptor/Gs-mediated effect in NPM cells measured in OAP. In contrast, OT further enhanced the beta-adrenoceptor/Gs-mediated effect on BKCa activity in PM cells. All OT effects in the OAP were mediated by pertussis toxin-sensitive Gi proteins and PKA. By quantitative real-time PCR and overexpression of the recombinant protein, we demonstrate that an up-regulation of the Gbetagamma-stimulated adenylyl cyclase II during pregnancy is most likely responsible for this switch. By studying the OT-evoked Iout in nystatin-perforated whole-cell patches of PM cells, we further detected that the OT receptor/Gibetagamma-mediated coactivation of adenylyl cyclase II enhanced the beta-adrenoceptor/Gs-induced suppression of the OT-evoked Ca2+ transients and thus diminishes and self-limits OT-induced contractility. The differential regulation of the PKA-mediated suppression of OT-evoked Ca2+ transients and BKCa activity likely supports uterine quiescence during pregnancy. PMID:17170070

Zhou, Xiao-Bo; Lutz, Susanne; Steffens, Frank; Korth, Michael; Wieland, Thomas



Effects of iron polymaltose complex, ferrous fumarate and ferrous sulfate treatments in anemic pregnant rats, their fetuses and placentas.  


Although oral iron preparations are widely prescribed to prevent and to treat iron deficiency anemia in pregnancy, comparative data on their effects to the mother, fetus and placenta are limited. In this study, the effects of oral iron polymaltose complex (IPC), ferrous fumarate (FF) and ferrous sulfate (FS) were compared in anemic pregnant rats, their fetuses and placentas. Hematological variables and oxidative stress markers in the liver, heart and kidneys of the dams and fetuses as well as the markers for oxidative stress, inflammation and hypoxia in placentas were assessed. Pregnancy outcome was measured by number of fetuses, and by neonate and placental weight. All therapies were comparably effective in correcting anemia. FS and FF, but not IPC, resulted in liver damage in dams and oxidative stress in dams, fetuses and placentas. FS group presented the highest catalase and GPx levels in dams, fetuses and placentas. IPC, but not FF or FS, restored normal TNF-? and IL6 expression levels in placentas whereas FS-treated animals presented the highest cytokine levels, suggesting a local inflammatory reaction. Anemia-induced high levels of HIF-1? were partially lowered by IPC and FF but further elevated by FS. Most of the negative effects associated with IDA were resolved by IPC treatment. Especially FS treatment was found to elicit hepatic damage in the dams, oxidative stress in the dams, fetuses and placenta as well as inflammation and high levels of HIF-1? in the placenta. Pregnancy outcome of FFand FS-treated animals was worse than that of IPC-treated animals. PMID:23547731

Toblli, Jorge E; Cao, Gabriel; Oliveri, Leda; Angerosa, Margarita



Effect of 6-mercaptopurine on /sup 65/Zn distribution in the pregnant rat  

SciTech Connect

The effect of 6-mercaptopurine (6-MP) on the distribution of gavaged /sup 65/Zn in maternal and embryonic tissues of Sprague-Dawley rats was examined 24 hr after injection of the drug on day 13 of pregnancy. 6-MP injection resulted in a significantly higher retention of counts of /sup 65/Zn in maternal liver and lower counts in maternal plasma, uterus, placenta, and embryo than in controls. Compared to controls, gel chromatography of maternal liver from 6-MP injected dams showed higher counts associated with a protein peak of molecular weight 6,000-8,000, the approximate molecular weight of the zinc-binding protein metallothionein. These results support the idea that the zinc deficiency, which is observed in day 21 fetuses from dams injected with 6-MP during midgestation, may be the result of a drug-induced sequestering of zinc into maternal liver followed by a decrease in maternal plasma zinc and subsequent reduction in fetal zinc uptake. We suggest that this 6-MP-associated redistribution of zinc into maternal liver may be due to induction of maternal metallothionein synthesis by the drug.

Amemiya, K.; Hurley, L.S.; Keen, C.L.



Coexpression of adrenomedullin and its receptor component proteins in the reproductive system of the rat during gestation  

Microsoft Academic Search

BACKGROUND: Adrenomedullin (ADM), a novel vasorelaxant peptide, was found in human\\/rat ovaries and uteri. Plasma ADM level increases in pregnant women and pregnant rats. METHODS: The gene expression levels of Adm and its receptor components - Crlr, Ramp1, Ramp2 and Ramp3, the ADM peptide concentration and localization in the rat female reproductive system during gestation were studied by real-time RT-PCR,

Lei Li; Fai Tang; Wai-Sum O



Maleate effects on kidney peptidases and proteinuria of male and female rats  

Microsoft Academic Search

Summary The effects of maleate on membrane-bound and lysosomal peptidases were studied histochemically in the kidney and biochemically in the kidney and the urine of male and female rats 6 h after the administration of two different doses of sodium maleate (150 and 300 mg\\/kg body weight). Additionally, the proteinuria of experimental animals was electrophoretically analysed to detect maleate-induced alterations

E. Asan; P. Kugler



Maternal treatment of spontaneously hypertensive rats with pentaerythritol tetranitrate reduces blood pressure in female offspring.  


Pentaerythritol tetranitrate is devoid of nitrate tolerance and shows no reproductive or developmental toxicity in animal studies. Recently, pentaerythritol tetranitrate has been demonstrated to reduce the risk of intrauterine growth restriction and the risk of preterm birth in women with abnormal placental perfusion. This study was conducted to test the perinatal programming effect of pentaerythritol tetranitrate in spontaneously hypertensive rats, a rat model of genetic hypertension. Parental spontaneously hypertensive rats were treated with pentaerythritol tetranitrate (50 mg/kg per day) during pregnancy and lactation periods; the offspring received standard chow without pentaerythritol tetranitrate after weaning. Maternal treatment with pentaerythritol tetranitrate had no effect on blood pressure in male offspring. In the female offspring, however, a persistent reduction in blood pressure was observed at 6 and 8 months. This long-lasting effect was accompanied by an upregulation of endothelial nitric oxide synthase, mitochondrial superoxide dismutase, glutathione peroxidase 1, and heme oxygenase 1 in the aorta of 8-month-old female offspring, which was likely to result from epigenetic changes (enhanced histone 3 lysine 27 acetylation and histone 3 lysine 4 trimethylation) and transcriptional activation (enhanced binding of DNA-directed RNA polymerase II to the transcription start site of the genes). In organ chamber experiments, the endothelium-dependent, nitric oxide-mediated vasodilation to acetylcholine was enhanced in aorta from female offspring of the pentaerythritol tetranitrate-treated parental spontaneously hypertensive rats. In conclusion, maternal pentaerythritol tetranitrate treatment leads to epigenetic modifications, gene expression changes, an improvement of endothelial function and a persistent blood pressure reduction in the female offspring. PMID:25385760

Wu, Zhixiong; Siuda, Daniel; Xia, Ning; Reifenberg, Gisela; Daiber, Andreas; Münzel, Thomas; Förstermann, Ulrich; Li, Huige



Internal Pudendal Artery from Type 2 Diabetic Female Rats Demonstrate Elevated Endothelin-1-Mediated Constriction  

PubMed Central

Introduction Diabetes is a risk factor for female sexual dysfunction (FSD). FSD has several etiologies, including a vasculogenic component that could be exacerbated in diabetes. The internal pudendal artery supplies blood to the vagina and clitoris and diabetes-associated functional abnormalities in this vascular bed may contribute to FSD. Aim The Goto-Kakizaki (GK) rat is a non-obese model of type 2 diabetes with elevated endothelin-1 (ET-1) activity. We hypothesize that female GK rats have diminished sexual responses and that the internal pudendal arteries demonstrate increased ET-1 constrictor sensitivity. Methods Female Wistar and GK rats were used. Apomorphine (APO)-mediated genital vasocongestive arousal (GVA) was measured. Functional contraction (ET-1 and phenylephrine) and relaxation (acetylcholine, ACh) in the presence or absence of the ETA receptor antagonist (ETAR; atrasentan) or Rho-kinase inhibitor (Y-27632) were assessed in the internal pudendal and mesenteric arteries. Protein expression of ET-1 and RhoA/Rho-kinase signaling pathway was determined in the internal pudendal and mesenteric arteries. Main Outcome Measure APO-mediated GVAs; contraction and relaxation of internal pudendal and mesenteric arteries; ET-1/RhoA/Rho-kinase protein expression. Results GK rats demonstrated no APO-induced GVAs. Internal pudendal arteries, but not mesenteric arteries, from GK rats exhibited greater contractile sensitivity to ET-1 compared with Wistar arteries. ETAR blockade reduced ET-1-mediated constriction in GK internal pudendal and mesenteric arteries. Rho-kinase inhibition reduced ET-1-mediated constriction of GK internal pudendal but not mesenteric arteries; however, it had no effect on arteries from Wistar rats. RhoA protein expression was elevated in GK internal pudendal arteries. At the highest concentrations, ACh-mediated relaxation was greater in the GK internal pudendal artery; however, no difference was observed in the mesenteric artery. Conclusions Female GK rats demonstrate decreased sexual responses that may be because of increased constrictor sensitivity to the ET-1/RhoA/Rho-kinase signaling in the internal pudendal artery. PMID:21718448

Allahdadi, Kyan J.; Hannan, Johanna L.; Ergul, Adviye; Tostes, Rita C.; Webb, R. Clinton



Possible existence of a long-loop feedback system between FSH and inhibin in female rats.  


Experiments were designed in which peripheral plasma inhibin levels were presumably altered in an attempt to investigate an interdependency between pituitary follicle-stimulating hormone (FSH) and ovarian inhibin secretion. In the first study, unilateral ovariectomy (ULO) was performed on 4-day cycling female rats under ether anesthesia at 0800 h on diestrous day 1 (D1). Inhibin-like activity [FSH-inhibiting activity(FSH-IA)] in untreated ovarian venous plasma (OVP) collected from the remaining ovary was assessed by an in vitro pituitary bioassay system. Both plasma FSH levels and FSH-IA significantly increased between 4 and 12 h after ULO. Thereafter, plasma FSH declined between 12 and 32 h after ULO, whereas FSH-IA remained elevated during this same time interval. Compared to sham-operated rats, plasma FSH was significantly elevated 4, 12, and 24 h after ULO, whereas FSH-IA was statistically higher only at 32 h after ULO. In a second experiment, rats were injected with charcoal-treated porcine follicular fluid (PFF) on proestrus and estrus. Control rats received saline. The data indicate that increased plasma FSH levels on D1 in PFF-treated rats (FSH rebound) may be a consequence of reduced endogenous inhibin secretion on estrus. As well, return of FSH to control levels on D2 in PFF-treated rats may have resulted from an FSH-associated increase in FSH-IA on D1 and D2. PMID:6786105

DePaolo, L V; Anderson, L D; Hirshfield, A N



Experimental gastritis leads to anxiety- and depression-like behaviors in female but not male rats.  


Human and animals studies support the idea that there is a gender-related co-morbidity of pain-related and inflammatory gastrointestinal (GI) diseases with psychological disorders. This co-morbidity is the evidence for the existence of GI-brain axis which consists of immune (cytokines), neural (vagus nerve) and neuroendocrine (HPA axis) pathways. Psychological stress causes disturbances in GI physiology, such as altered GI barrier function, changes in motility and secretion, development of visceral hypersensitivity, and dysfunction of inflammatory responses. Whether GI inflammation would exert impact on psychological behavior is not well established. We examined the effect of experimental gastritis on anxiety- and depression-like behaviors in male and female Sprague-Dawley rats, and evaluated potential mechanisms of action. Gastritis was induced by adding 0.1% (w/v) iodoacetamide (IAA) to the sterile drinking water for 7 days. Sucrose preference test assessed the depression-like behavior, open field test and elevated plus maze evaluated the anxiety-like behavior. IAA treatment induced gastric inflammation in rats of either gender. No behavioral abnormality or dysfunction of GI-brain axis was observed in male rats with IAA-induced gastritis. Anxiety- and depression-like behaviors were apparent and the HPA axis was hyperactive in female rats with IAA-induced gastritis. Our results show that gastric inflammation leads to anxiety- and depression-like behaviors in female but not male rats via the neuroendocrine (HPA axis) pathway, suggesting that the GI inflammation can impair normal brain function and induce changes in psychological behavior in a gender-related manner through the GI-to-brain signaling. PMID:24345032

Luo, Jia; Wang, Tao; Liang, Shan; Hu, Xu; Li, Wei; Jin, Feng



TITLE Disposition and kinetics of Tetrabromobisphenol A in female Wistar Han rats  

PubMed Central

Tetrabromobisphenol A (TBBPA) is the brominated flame retardant with the largest production volume worldwide. NTP 2-year bioassays found TBBPA dose-dependent increases in uterine tumors in female Wistar Han rats; evidence of reproductive tissues carcinogenicity was equivocal in male rats. To explain this apparent sex-dependence, the disposition and toxicokinetic profile of TBBPA were investigated using female Wistar Han rats, as no data were available for female rats. In these studies, the primary route of elimination following [14C]-TBBPA administration (25, 250 or 1,000 mg/kg) was in feces; recoveries in 72 h were 95.7±3.5%, 94.3±3.6% and 98.8±2.2%, respectively (urine: 0.2-2%; tissues: <0.1). TBBPA was conjugated to mono-glucuronide and —sulfate metabolites and eliminated in the bile. Plasma toxicokinetic parameters for a 250 mg/kg dose were estimated based on free TBBPA, as determined by UV/radiometric-HPLC analyses. Oral dosing by gavage (250 mg/kg) resulted in a rapid absorption of compound into the systemic circulation with an observed Cmax at 1.5 h post-dose followed by a prolonged terminal phase. TBBPA concentrations in plasma decreased rapidly after an IV dose (25 mg/kg) followed by a long elimination phase. These results indicate low systemic bioavailability (F<0.05), similar to previous reports using male rats. Elimination pathways appeared to become saturated leading to delayed excretion after a single oral administration of the highest dose (1,000 mg/kg); no such saturation or delay was detected at lower doses. Chronic high exposures to TBBPA may result in competition for metabolism with endogenous substrates in extrahepatic tissues (e.g., SULT1E1 estrogen sulfation) resulting in endocrine disruption. PMID:24977115

Knudsen, Gabriel A.; Sanders, J. Michael; Sadik, Abdella M.; Birnbaum, Linda S.



Aloe vera Aqueous Extract Effect on Morphine Withdrawal Syndrome in Morphine-Dependent Female Rats  

PubMed Central

Background: Aloe vera is a medicinal herb used as an anti-inflammatory and sedative agent. Objectives: The current study aimed to evaluate the effect of Aloe vera aqueous extract on morphine withdrawal symptoms in morphine-dependent female rats. Patients and Methods: The current research was performed on 40 female Wista-Albino rats which were made dependent on morphine using Houshyar protocol and were randomly divided into five groups (A, B, C, D, and E). Group A did not receive any agent in the period of handling but other groups (B, C, D and E) received 5, 10, 20 and 40 mg/kg of Aloe vera aqueous extract by gavage, three times daily for a week, respectively. Withdrawal symptoms, stool form, agitation, disparity, floppy eyelids, and body mass variations were checked for 10 days. The obtained data were analyzed using SPSS v.11 software, and Friedman, Kruskal-Wallis, and Mann-Whitney statistical tests. Statistical difference was considered significant (P < 0.05). Results: The results of the present study showed that agitation, disparity, and floppy eyelids in group E were significantly higher than those of others groups; however, these symptoms in group C were significantly lower than those of the other groups. Conclusions: The results of the present study revealed that the Aloe vera aqueous extract had various effects on morphine withdrawal syndrome in morphine-dependent female rats . PMID:25593890

Shahraki, Mohammad Reza; Mirshekari, Hamideh; Sabri, Azame



Detecting Early Biomechanical Effects of Zoledronic Acid on Femurs of Osteoporotic Female Rats  

PubMed Central

Aim. To investigate the biomechanical effects of zoledronic acid (ZA) on femurs of female osteoporotic rats after follow-up periods of 9 and 12 months. Methods. Eighty female Wistar rats were prospectively assessed. At 60 days of age, the animals were randomly divided into two groups: bilateral oophorectomy (O) (n = 40) and sham surgery (S) (n = 40). At 90 days of age, groups O and S were randomly subdivided into four groups, according to whether 0.1?mg/kg of ZA or distilled water (DW) was intraperitoneally administered: OZA (n = 20), ODW (n = 20), SZA (n = 20), and SDW (n = 20). The animals were sacrificed at 9 and 12 months after the administration of the substances, and then their right femurs were removed and analyzed biomechanically. Axial compression tests that focused on determining the maximum load (N), yield point (N), and stiffness coefficient (N/mm) of the proximal femur were performed in the biomechanical study. Results. ZA significantly increased the maximum load and yield point, reducing the stiffness coefficient concerning the oophorectomy status and follow-up period. Conclusion. Zoledronic acid, at a dose of 0.1?mg/kg, significantly increased the maximum loads and yield points and reduced the stiffness coefficients in the femurs of female rats with osteoporosis caused by bilateral oophorectomy. PMID:23304634

Palacio, Evandro Pereira; Müller, Sérgio Swain; Sardenberg, Trajano; Mizobuchi, Roberto Ryuiti; Galbiatti, José Antônio; Durigan, Alcides; Savarese, Aniello; Ortolan, Érika Veruska Paiva



Effects of Hypergravity Exposure on Plasma Oxytocin (OT) Concentrations in Pregnant and Lactating Rat Dams  

NASA Technical Reports Server (NTRS)

From pregnancy to weaning there is a progressive elevation of plasma oxytocin (OT) levels associated with nursing activity, irrespective of litter size. In the present study, we analyzed the effects of continuous 1.5G, 1.75G and 2.0G hypergravity exposure on OT plasma concentration in prepartum (Gestation Day 20) (G20) and lactating (Postnatal day) (P10) rat dams. For this study, litter size was controlled with a yoking procedure established in our lab where individual control litters were yoked-matched to individual hypergravity litters. We reviewed all data at hypergravity irrespective of gravitational level and compared the values with the controls in both G20 (HG, n=15;SC, n=9) and P10 (HG, n=21;SC, n=16). Results showed that over time, we did observe the expected OT increase in both groups. In G20 dams, measurement of OT concentrations showed no significance. However, at P10, measurements of OT concentrations suggest a reduction of about 20% compared to established controls in our laboratory, 0.9+/-0.09 ng/ml for the controls and 0.7+/-0.06 ng/ml for centrifuged animals (p<0.02). These data suggest that exposure to centrifugation may reduce OT levels during lactation. When these plasma samples were obtained, the dams were removed from the litters, and values were not adjusted for the size of the litters. The reduction in OT with centrifugation may reflect a decrease in nursing activity or a decreased responsiveness of the mammary hypothalamic axis. In addition, we have analyzed data on plasma prolactin concentrations and mammary gland development, which may give additional insight to the results of our OT measurements.

Baer, Lisa A.; Wade, Charles E.; Plaut, Karen; Ronca, April E.; Dalton, Bonnie (Technical Monitor)



Dietary Quercetin Exacerbates the Development of Estrogen-Induced Breast Tumors in Female ACI Rats  

PubMed Central

Phytoestrogens are plant compounds that structurally mimic the endogenous estrogen 17?-estradiol (E2). Despite intense investigation, the net effect of phytoestrogen exposure on the breast remains unclear. The objective of the current study was to examine the effects of quercetin on E2-induced breast cancer in vivo. Female ACI rats were given quercetin (2.5 g/kg food) for 8 months. Animals were monitored weekly for palpable tumors, and at the end of the experiment, rats were euthanized, breast tumor and different tissues excised so that they could be examined for histopathologic changes, estrogen metabolic activity and oxidant stress. Quercetin alone did not induce mammary tumors in female ACI rats. However, in rats implanted with E2 pellets, co-exposure to quercetin did not protect rats from E2-induced breast tumor development with 100% of the animals developing breast tumors within 8 months of treatment. No changes in serum quercetin levels were observed in quercetin and quercetin + E2-treated groups at the end of the experiment. Tumor latency was significantly decreased among rats from the quercetin + E2 group relative to those in the E2 group. Catechol-O-methyltransferase (COMT) activity was significantly downregulated in quercetin exposed mammary tissue. Analysis of 8-isoprostane F2? (8-iso-PGF2?) levels as a marker of oxidant stress showed that quercetin did not decrease E2-induced oxidant stress. These results indicate that quercetin (2.5 g/kg food) does not confer protection against breast cancer, does not inhibit E2-induced oxidant stress and may exacerbate breast carcinogenesis in E2-treated ACI rats. Inhibition of COMT activity by quercetin may expose breast cells chronically to E2 and catechol estrogens. This would permit longer exposure times to the carcinogenic metabolites of E2 and chronic exposure to oxidant stress as a result of metabolic redox cycling to estrogen metabolites, and thus quercetin may exacerbate E2-induced breast tumors in female ACI rats. PMID:20600213

Singh, Bhupendra; Mense, Sarah M.; Bhat, Nimee K.; Putty, Sandeep; Guthiel, William A.; Remotti, Fabrizio; Bhat, Hari K.



Proliferative retinopathy and neovascularization of the anterior segment in female type 2 diabetic rats  

PubMed Central

Background To examine the presence of diabetic retinopathy in a female rat model of type 2 diabetes fed on a high-fat diet (HFD). Methods Wistar rats were injected with streptozotocin (STZ) at the age of two days and fed on an HFD from eight weeks onwards. Five diabetic animals were euthanized at 110 weeks of disease, together with a control group of age-matched, non-diabetic animals. A group of diabetic animals at 57 weeks of disease was included for comparison. Cross sections of the rats’ corneas, iris and retinas were histologically examined and analysed by immunohistochemistry and immunofluorescence, using glial-fibrillary-acidic-protein (GFAP), the vascular endothelial growth factor (VEGF) and the Von Willebrand factor (vWF). The trypsine digestive technique was used for the pericytes count. Results Neovascularization was only found in the retinas, irises and corneas of the diabetic animals of 110 weeks of disease. There was also a significantly lower number of pericytes in these animals than in the controls. Conclusion The female rat model of type 2 diabetes fed on an HFD may prove useful in evaluating the mechanisms involved in diabetic retinopathy, together with strategies to reduce its severity. PMID:24499599



Female-predominant occurrence of spontaneous gastric adenocarcinoma in cotton rats.  


In a colony of cotton rats (Sigmodon hispidus) consisting of 258 female and 283 male animals, 61 females and 2 males had a gastric mucosal lesion. This lesion developed in rats over 2 months of age, with a gradual increase in incidence thereafter. The lesion was grossly characterized by diffuse, often irregular thickening of the fundic mucosa, but the antrum was not affected. In 46% of the rats with this lesion, the serosal surface of the stomach was also involved. There was no evidence of disseminating or blood-borne metastasis. Histologically the mucosal thickening indicated a monotonous, diffuse proliferation of gastric glands with slight nuclear atypia, interpreted to be adenomatous hyperplasia. Invasion into submucosal, muscular, and subserosal layers by neoplastic cells with more atypia than the adenomatous hyperplasia was also noted and interpreted to be a tubular adenocarcinoma. In the adenocarcinoma lesions the infiltrating glands were surrounded by a desmoplastic reaction. In several of the adenocarcinoma lesions there were poorly differentiated adenocarcinoma cells with distorted gland formation. Lesions were diagnosed by soft X-ray examination with barium, without the need for laparotomy. Because these combined data demonstrate the spontaneous occurrence of gastric adenocarcinoma in the background of adenomatous hyperplasia, this cotton rat model can be used to examine, in minute detail, multistep carcinogenesis in the digestive tract. PMID:7650892

Kawase, S; Ishikura, H




EPA Science Inventory

RTD-03-031 Goldman, JM and Murr, AS. Dibromoacetic Acid-induced Elevations in Circulating Estradiol: Effects in Both Cycling and Ovariectomized/Steroid-primed Female Rats. Reproductive Toxicology (in press). Abstract Oral exposures to high concentrations of th...


In vivo exposure of female rats to toxicants may affect oocyte quality.  


A potential endpoint for female reproductive toxicants is fertilizability of the oocytes. This endpoint has not been adequately examined for mammalian females. The objective of these studies was to evaluate fertilizability of rat oocytes following in vivo exposure to known male reproductive toxicants that exert effects via pathways that do not include endocrine disruption and to 4-vinylcyclohexene diepoxide, known to interfere with early follicular development. Oocytes were obtained from females following exposure and quality assessed by in vitro fertilization rate. One study evaluated fertilizability following 2 weeks exposure of females to inhaled tetrachloroethylene (2h/day, 5 days/week). The remaining studies evaluated fertilizability immediately following 2 weeks exposure via drinking water to tetrachloroethylene, trichloroethylene, the fuel oxidants methyl tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE), tertiary amyl methyl ether (TAME), and a metabolite of the first two ethers 2-methyl-1,2-propanediol (2M2P), and to 4-vinylcyclohexene diepoxide. The percentage of oocytes fertilized was reduced following inhalation exposure to tetrachloroethylene, or consumption of trichloroethylene or TAME. Fertilizability was not altered by exposures to the other reproductive toxicants or to the other fuel oxidants. Consistent with the reduced oocyte fertilizability following exposure to trichloroethylene, oocytes from exposed females had a reduced ability to bind sperm plasma membrane proteins. Female reproductive capability assessed by the endpoint, oocyte fertilizability, was reduced by exposure to trichloroethylene and inhaled tetrachloroethylene. PMID:12759095

Berger, Trish; Horner, Catherine M



Protein Malnutrition Attenuates Bone Anabolic Response to PTH in Female Rats.  


PTH is indicated for the treatment of severe osteoporosis. Elderly osteoporotic patients frequently suffer from protein malnutrition, which may contribute to bone loss. It is unknown whether this malnutrition may affect the response to PTH. Therefore, the aim of the present study was to assess whether an isocaloric low-protein (LP) diet may influence the bone anabolic response to intermittent PTH in 6-month-old female rats. Six-month-old female rats were either pair fed an isocaloric LP diet (2.5% casein) or a normal-protein (NP) diet (15% casein) for 2 weeks. The rats continued on their respective diet while being treated with 5- or 40-?g/kg recombinant human PTH amino-terminal fragment 1-34 (PTH-[1-34]) daily, or with vehicle for 4 weeks. At the end of this period, areal bone mineral density, bone mineral content, microstructure, and bone strength in axial compression of proximal tibia or 3-point bending for midshaft tibia tests were measured. Blood was collected for the determination of IGF-I and osteocalcin. After 4 weeks of PTH-(1-34), the dose-dependent increase of proximal tibia bone mineral density, trabecular microstructure variables, and bone strength was attenuated in rats fed a LP diet as compared with rats on a NP intake. At the level of midshaft tibia cortical bone, PTH-(1-34) exerted an anabolic effect only in the NP but not in the LP diet group. Protein malnutrition was associated with lower IGF-I levels. Protein malnutrition attenuates the bone anabolic effects of PTH-(1-34) in rats. These results suggest that a sufficient protein intake should be recommended for osteoporotic patients undergoing PTH therapy. PMID:25396268

Ammann, P; Zacchetti, G; Gasser, J A; Lavet, C; Rizzoli, R



Effects of maternal exposure to the galactagogue Sulpiride on reproductive parameters in female rats.  


The antipsychotic Sulpiride has been documented as an effective galactagogue that acts blocking dopamine receptors, increasing prolactin concentrations. However, this drug passes through the milk exposing neonates during postnatal development, which may result in functional and morphological alterations in adult life. Therefore, the aim of this study was to investigate whether maternal exposure to Sulpiride during lactation could impair reproductive development of female offspring. The dams were treated daily by gavage with Sulpiride doses of 2.5mg/Kg (SUL 2.5mg group) and 25mg/Kg (SUL 25mg group), or distilled water (Control group) throughout the lactation period. During early life, body weight, anogenital distance, and vaginal opening were analyzed on the female offspring. In adulthood, estrous cycle, sexual behavior, estrogen levels as well as the weight of the reproductive organs were evaluated. There were no differences regarding body weight, anogenital distance, puberty onset, frequency and duration of the estrous cycle and estradiol levels on female offspring. Nonetheless, there were changes in sexual behavior. There was an increase in the number of observations in reflex magnitude 0 (absence of lordosis) and reflex magnitude 2 as well as a reduction of reflex magnitude 3 in the rats of SUL 25mg group in relation to the Control group, suggesting a decrease in sexual receptivity of these animals. These results demonstrate that maternal exposure to Sulpiride can alter reproductive function in female offspring rats. PMID:25554483

de Azevedo Camin, Nathália; Vieira, Milene Leivas; Montagnini, Bruno Garcia; Kiss, Ana Carolina Inhasz; Gerardin, Daniela Cristina Ceccatto



The influence of sleep deprivation and obesity on DNA damage in female Zucker rats  

PubMed Central

OBJECTIVE: The aim of this study was to evaluate overall genetic damage induced by total sleep deprivation in obese, female Zucker rats of differing ages. METHOD: Lean and obese Zucker rats at 3, 6, and 15 months old were randomly distributed into two groups for each age group: home-cage control and sleep-deprived (N?=?5/group). The sleep-deprived groups were deprived sleep by gentle handling for 6 hours, whereas the home-cage control group was allowed to remain undisturbed in their home-cage. At the end of the sleep deprivation period, or after an equivalent amount of time for the home-cage control groups, the rats were brought to an adjacent room and decapitated. The blood, brain, and liver tissue were collected and stored individually to evaluate DNA damage. RESULTS: Significant genetic damage was observed only in 15-month-old rats. Genetic damage was present in the liver cells from sleep-deprived obese rats compared with lean rats in the same condition. Sleep deprivation was associated with genetic damage in brain cells regardless of obesity status. DNA damage was observed in the peripheral blood cells regardless of sleep condition or obesity status. CONCLUSION: Taken together, these results suggest that obesity was associated with genetic damage in liver cells, whereas sleep deprivation was associated with DNA damage in brain cells. These results also indicate that there is no synergistic effect of these noxious conditions on the overall level of genetic damage. In addition, the level of DNA damage was significantly higher in 15-month-old rats compared to younger rats. PMID:23644860

Tenorio, Neuli M.; Ribeiro, Daniel A.; Alvarenga, Tathiana A.; Fracalossi, Ana Carolina C.; Carlin, Viviane; Hirotsu, Camila; Tufik, Sergio; Andersen, Monica L.



2,2,4-Trimethylpentane-induced nephrotoxicity. I. Metabolic disposition of TMP in male and female Fischer 344 rats  

Microsoft Academic Search

2,2,4-Trimethylpentane (TMP), a component of unleaded gasoline, causes nephrotoxicity in male, but not in female, rats. In the present study, male and female Fischer 344 rats were treated with a single oral dose of (¹⁴C)TMP (4.4 mmol\\/kg; 2 microCi\\/mmol). Radiolabeled material in kidney, liver, and plasma was determined at 4, 8, 12, 24, and 48 hr after dosing. Maximum concentration

M. Charbonneau; E. A. Lock; J. Strasser; M. G. Cox; M. J. Turner; J. S. Bus



Effect of six antiretroviral drugs (delavirdine, stavudine, lamivudine, nelfinavir, amprenavir and lopinavir/ritonavir in association) on albino pregnant rats (Rattus norvegicus Albinus, Rodentia, Mammalia): biological assay.  


Objective: To compare the chronic effects of antiretrovirals (lamivudine, stavudine, delavirdine, nelfinavir, amprenavir and an association of lopinavir/ritonavir) on albino pregnant rats.Design: Review.Setting: Department of Obstetrics, Federal University of São Paulo (UNIFESP), São Paulo, SP, Brazil.Methods: This was a comparative retrospective study formed by 18 groups of 10 pregnant rats each, which were nearly three months of age and weighed 200 g. All of them were medicated every day using a stomach probe, while the control group was given 1 mL of distilled water. The study groups received lamivudine (at 5, 15 and 45 mg/kg/day); stavudine (at 1, 3 and 9 mg/kg/day); nelfinavir (at 40, 120 and 360 mg/kg/day); amprenavir (at 46, 138 and 414 mg/kg/day); lopinavir/ritonavir (at 12.8/3.2, 38.4/9.6 and 115/28.8 mg/kg/day) and delavirdine (at 20 and 60 mg/kg/day). These represented 1, 3 and 9 times the human therapeutic dose, except for the last drug, for which the 9-times dose was not used. Maternal, litter and placental weights, implantation and reabsorption numbers, major external fetal malformations and fetal and maternal deaths were evaluated. The Kruskal-Wallis test was used to compare quantitative variables and the chi-square test was used to compare qualitative variables.Results: At all three doses, stavudine increased the maternal weight (p=0.001), while lamivudine at 3- and 9-times doses reduced it (p<0.001). Amprenavir at all of the doses, and lopinavir/ritonavir at 3- and 9-times doses, caused higher rates of maternal death (p<0.001). Regarding the fetuses, none of the antiretroviral drugs studied were harmful with regard to implantation, reabsorption, teratogenity and mortality (p>0.05). Stavudine at all doses reduced the litter weights (p<0.001); however, lamivudine at the usual and 3-times doses, delavirdine at 3-times dose, and amprenavir at 3-times dose increased the litter weight (p<0.001).Conclusion: In the maternal compartment, we observed lethal toxicity in the pregnant rats that received amprenavir and ritonavir/lopinavir; and maternal weight change with lamivudine and stavudine. In the fetal compartment, adverse effects were observed in relation to litter weight from stavudine, lamivudine, delavirdine and amprenavir.Keywords: pregnant rats, antiretroviral drugs, teratology, biological assay. PMID:25398151

Nakamura, M U; Araujo, E Júnior; Simões, J M; Oliveria, R M Filho; Kulay, L Júnior



Discrete Lesions Reveal Functional Heterogeneity of Suprachiasmatic Structures in Regulation of Gonadotropin Secretion in the Female Rat  

Microsoft Academic Search

The present study examines the function of several cytologically distinct suprachiasmatic structures in the regulation of ovulation and positive feedback effects of estrogen and progesterone on gonadotropin release in the rat. Small (0.6–0.8 mm dia.) electrolytic lesions were placed at four loci along the rostrocaudal extent of the suprachiasmatic region in regularly cycling female rats. Anovulatory persistent estrus occurred only

Stanley J. Wiegand; Ei Terasawa



Effects of Medroxyprogesterone Acetate and Caloric Restriction on the Distribution of Serum and Liver Lipids and Proteins in Female Rats  

Microsoft Academic Search

The effects of a large dose (2 mg\\/100 g body weight) of me- droxyprogesterone acetate (MPA), restricted feeding (50% of normal intake) and their interaction were investigated on the serum and liver lipid and protein distribution in female rats. MPA increased serum cholesterol and triglycéride levels in rats on ad libitum food intake without having any effect in the animals




Effects of Salsalate Therapy on Recovery From Vascular Injury in Female Zucker Fatty Rats  

PubMed Central

OBJECTIVE Salsalate is a dimeric form of salicylic acid that has been shown to have anti-inflammatory activity and to reduce glucose levels, insulin resistance, and cytokine expression. However, the effect of salsalate on vascular injury has not been determined. The objective of this study is to investigate the effect of salsalate on vascular injury and repair in a rat model of carotid artery balloon catheter injury. RESEARCH DESIGN AND METHODS Salsalate treatment was started in female Zucker fatty rats (insulin resistant) 1 week before carotid artery balloon catheter injury and continued for 21 days, at which time the animals were killed and studied. RESULTS Treatment with salsalate significantly decreased the intima-to-media ratio and upregulated the expression of aortic endothelial nitric oxide synthase (eNOS), phosphorylated eNOS (p-eNOS) (ser 1177), and manganese superoxide dismutase (MnSOD) and reduced serum interleukin (IL)-6 with concomitant downregulation of nuclear factor (NF) ?B subunit p65 and vascular endothelial growth factor (VEGF) expression in the balloon-injured carotid artery of female Zucker fatty rats. CONCLUSIONS The present study shows that salsalate treatment decreases vascular damage caused by balloon catheter injury in female Zucker fatty rats. The beneficial effect of salsalate on vascular injury was associated with upregulation of eNOS, p-eNOS, and MnSOD, which reduce oxidative stress and have anti-inflammatory properties, as evidenced by reduction in serum IL-6 and the downregulation of VEGF and NF?B, which promote inflammation without changing glucose levels. These results suggest that salsalate may be useful in reducing vascular injury and restenosis following interventional revascularization procedures. PMID:20876710

Murthy, Subramanyam N.; Desouza, Cyrus V.; Bost, Neal W.; Hilaire, Rose-Claire St.; Casey, David B.; Badejo, Adeleke M.; Dhaliwal, Jasdeep S.; McGee, Jennifer; McNamara, Dennis B.; Kadowitz, Philip J.; Fonseca, Vivian A.



Linkage Screen for BMD Phenotypes in Male and Female COP and DA Rat Strains  

PubMed Central

Because particular inbred strains of experimental animals are informative for only a subset of the genes underlying variability in BMD, we undertook a genome screen to identify quantitative trait loci (QTLs) in 828 F2 progeny (405 males and 423 females) derived from the Copenhagen 2331 (COP) and dark agouti (DA) strains of rats. This screen was performed to complement our study in female Fischer 344 (F344) and Lewis (LEW) rats and to further delineate the factors underlying the complex genetic architecture of BMD in the rat model. Microsatellite genotyping was performed using markers at an average density of 20 cM. BMD was measured by pQCT and DXA. These data were analyzed in the R/qtl software to detect QTLs acting in both sexes as well as those having sex-specific effects. A QTL was detected in both sexes on chromosome 18 for midfemur volumetric BMD (vBMD; genome-wide, p < 0.01). On distal chromosome 1, a QTL was found for femur and vertebral aBMD as well as distal femur vBMD, and this QTL appears distinct from the proximal chromosome 1 QTL impacting BMD in our F344/LEW cross. Additional aBMD and vBMD QTLs and several sex-specific QTLs were also detected. These included a male-specific QTL (p < 0.01) on chromosome 8 and a female-specific QTL on chromosomes 7 and 14 (p < 0.01). Few of the QTLs identified showed overlap with the significant QTLs from the F344/LEW cross. These results confirm that the genetic influence on BMD in the rat model is quite complex and would seem to be influenced by a number of different genes, some of which have sex-specific effects. PMID:18707222

Koller, Daniel L; Liu, Lixiang; Alam, Imranul; Sun, Qiwei; Econs, Michael J; Foroud, Tatiana; Turner, Charles H



Rapid and Acute Effects of Estrogen on Time Perception in Male and Female Rats  

PubMed Central

Sex differences in the rapid and acute effects of estradiol on time perception were investigated in adult male and female Sprague-Dawley rats. Because estradiol has been shown to increase striatal dopamine release, it may be able to modify time perception and timed performance by increasing the speed of an internal clock in a manner similar to indirect dopamine agonists such as amphetamine and cocaine. Two groups of females (neonatally estradiol-treated/adult ovariectomized and neonatally oil-treated/adult ovariectomized) and two groups of males (neonatally castrated and adult castrated) were trained in a 2 vs. 8-s duration bisection procedure and tested using intermediate signal durations. After obtaining oil-injected baseline psychometric functions over several days, rats were administered 5??g of estradiol for 4?days and behaviorally evaluated 30?min following each injection. This oil–estradiol administration cycle was subsequently repeated three times following the re-establishment of baseline training. Results revealed significant sex differences in the initial baseline functions that were not modifiable by organizational hormones, with males’ duration bisection functions shifted horizontally to the left of females’. Upon the first administration of estradiol, females, but not males, showed a significant, transient leftward shift in their bisection functions, indicative of an increase in clock speed. After extensive retraining in the duration bisection procedure, rats that were exposed to gonadal hormones during the first week of life showed a significant rightward shift in their bisection functions on the fourth day of estradiol administration during each cycle, suggesting a decrease in clock speed. Taken together, our results support the view that there are multiple mechanisms of estrogens’ action in the striatum that modulate dopaminergic activity and are differentially organized by gonadal steroids during early brain development. PMID:22016725

Pleil, Kristen E.; Cordes, Sara; Meck, Warren H.; Williams, Christina L.



Loss of ovarian estrogens causes only mild deterioration of glucose homeostasis in female ZDF rats preventable by voluntary running exercise.  


Studies on normoglycemic ovariectomized Sprague-Dawley rats have provided insights about the effects of estrogen deficiency on insulin resistance in lean individuals. It is not completely clear if subjects with pre-established obesity and insulin resistance are at greater risk of developing type 2 diabetes when ovarian estrogens are no longer secreted, and if physical activity can protect against this susceptibility. Contrasting with their male counterparts, obese and insulin resistant female ZDF (Zucker diabetic fatty) rats do not become hyperglycemic when fed a standard diet. The aim of the study was to evaluate the hypothesis that withdrawal of ovarian estrogens in insulin resistant female ZDF rats would trigger overt hyperglycemia, provided they remain physically inactive. Female ZDF rats underwent either an ovariectomy (OVX) or a simulated surgery (SHAM). Thereafter, OVX rats engaged either in voluntary wheel cage running (OVX-Active), or like the Sham rats, remained sedentary (OVX-Sed) for 6 weeks. Fasting glycemia, insulinemia, and glucose tolerance were not altered in OVX-Sed as compared to SHAM-Sed rats. However, OVX-Sed rats showed altered liver triglyceride and glycogen contents, increased pancreatic insulin content and reduced insulin-stimulated muscle pAKT as compared to SHAM-Sed rats. Physical activity in OVX rats lowered fasting glucose and insulin levels, improved glucose tolerance and insulin-stimulated skeletal muscle glucose uptake as compared to OVX-Sed rats. OVX-induced alterations in pancreatic insulin content and liver glycogen and triglyceride contents were significantly improved by physical activity. Loss of ovarian estrogens did not cause overt hyperglycemia in insulin-resistant female ZDF rats. Physical activity improved glucose homeostasis despite estrogen deficiency. PMID:24983383

Bergeron, R; Mentor, J S; Côté, I; Ngo Sock, É T; Rabasa-Lhoret, R; Lavoie, J M



Differential Activity of Thymosin Peptides (Thymosin Fraction 5) on Plasma Thyrotropin in Female Rats of Different Ages  

Microsoft Academic Search

Thymosin fraction 5 (TF-5), a partially purified thymic preparation, has been previously shown to have luteinizing-hormone-releasing-hormone-releasing activity in perfused rat hypothalamus as well as an in vivo stimulatory effect on the pituitary-adrenal axis in prepubertal monkeys. We report here the effect of TF-5 on the plasma levels of several hormones in female rats of different ages. Conscious free-moving Sprague-Dawley rats

Rodolfo G. Goya; Yolanda E. Sosa; Kathleen L. Quigley; Paul E. Gottschall; Allan L. Goldstein; Joseph Meites



Ovariectomy Results in Variable Changes in Nociception, Mood and Depression in Adult Female Rats  

PubMed Central

Decline in the ovarian hormones with menopause may influence somatosensory, cognitive, and affective processing. The present study investigated whether hormonal depletion alters the nociceptive, depressive-like and learning behaviors in experimental rats after ovariectomy (OVX), a common method to deplete animals of their gonadal hormones. OVX rats developed thermal hyperalgesia in proximal and distal tail that was established 2 weeks after OVX and lasted the 7 weeks of the experiment. A robust mechanical allodynia was also occurred at 5 weeks after OVX. In the 5th week after OVX, dilute formalin (5%)-induced nociceptive responses (such as elevating and licking or biting) during the second phase were significantly increased as compared to intact and sham-OVX females. However, chronic constriction injury (CCI) of the sciatic nerve-induced mechanical allodynia did not differ as hormonal status (e.g. OVX and ovarian intact). Using formalin-induced conditioned place avoidance (F-CPA), which is believed to reflect the pain-related negative emotion, we further found that OVX significantly attenuated F-CPA scores but did not alter electric foot-shock-induced CPA (S-CPA). In the open field and forced swimming test, there was an increase in depressive-like behaviors in OVX rats. There was no detectable impairment of spatial performance by Morris water maze task in OVX rats up to 5 weeks after surgery. Estrogen replacement retrieved OVX-induced nociceptive hypersensitivity and depressive-like behaviors. This is the first study to investigate the impacts of ovarian removal on nociceptive perception, negative emotion, depressive-like behaviors and spatial learning in adult female rats in a uniform and standard way. PMID:24710472

Li, Li-Hong; Wang, Zhe-Chen; Yu, Jin; Zhang, Yu-Qiu



Developmental treatment with ethinyl estradiol, but not bisphenol A, causes alterations in sexually dimorphic behaviors in male and female Sprague Dawley rats.  


The developing central nervous system may be particularly sensitive to bisphenol A (BPA)-induced alterations. Here, pregnant Sprague Dawley rats (n = 11-12/group) were gavaged daily with vehicle, 2.5 or 25.0 ?g/kg BPA, or 5.0 or 10.0 ?g/kg ethinyl estradiol (EE2) on gestational days 6-21. The BPA doses were selected to be below the no-observed-adverse-effect level (NOAEL) of 5 mg/kg/day. On postnatal days 1-21, all offspring/litter were orally treated with the same dose. A naïve control group was not gavaged. Body weight, pubertal age, estrous cyclicity, and adult serum hormone levels were measured. Adolescent play, running wheel activity, flavored solution intake, female sex behavior, and manually elicited lordosis were assessed. No significant differences existed between the vehicle and naïve control groups. Vehicle controls exhibited significant sexual dimorphism for most behaviors, indicating these evaluations were sensitive to sex differences. However, only EE2 treatment caused significant effects. Relative to female controls, EE2-treated females were heavier, exhibited delayed vaginal opening, aberrant estrous cyclicity, increased play behavior, decreased running wheel activity, and increased aggression toward the stimulus male during sexual behavior assessments. Relative to male controls, EE2-treated males were older at testes descent and preputial separation and had lower testosterone levels. These results suggest EE2-induced masculinization/defeminization of females and are consistent with increased volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) at weaning in female siblings of these subjects (He, Z., Paule, M. G. and Ferguson, S. A. (2012) Low oral doses of bisphenol A increase volume of the sexually dimorphic nucleus of the preoptic area in male, but not female, rats at postnatal day 21. Neurotoxicol. Teratol. 34, 331-337). Although EE2 treatment caused pubertal delays and decreased testosterone levels in males, their behaviors were within the range of control males. Conversely, BPA treatment did not alter any measured endpoint. Similar to our previous reports (Ferguson, S. A., Law, C. D. Jr and Abshire, J. S. (2011) Developmental treatment with bisphenol A or ethinyl estradiol causes few alterations on early preweaning measures. Toxicol. Sci. 124, 149-160; Ferguson, S. A., Law, C. D. and Abshire, J. S. (2012) Developmental treatment with bisphenol A causes few alterations on measures of postweaning activity and learning. Neurotoxicol. Teratol. 34, 598-606), the BPA doses and design used here produced few alterations. PMID:24798382

Ferguson, Sherry A; Law, Charles Delbert; Kissling, Grace E



Helix stabilization in the C-terminal peptide of chicken riboflavin carrier protein enhances immunogenicity and prolongs contraceptive potential as an epitope-based vaccine in female rats.  


Earlier investigations have shown that (a) antibodies against a carrier-coupled 20-residue synthetic peptide (C-20), (200)HACQKKLLKFEALQQEEGEE(219), corresponding to the C-terminal partially helical sequence of chicken riboflavin carrier protein (RCP; 219 AA) curtail pregnancy in mammals and (b) helix stabilization by introducing appropriately spaced salt bridges in the flanking sequences of its B-cell epitopic structure enhances RCP antigenicity to peptide antibodies. Among such engineered C-20 analogs, HE-20 (HAEQKKLLKFEALEQEKGKE) exhibited maximum helical propensity. Since C-20 per se, i.e., without carrier conjugation, elicits RCP-reactive neutralizing antibodies in rodents, we mapped its T-cell epitope which overlaps its B-cell epitope, both of which remain unmodified in HE-20. Comparative evaluation of immunogenicity of the two epitope-based peptide vaccines showed that HE-20 was far superior to C-20 in generating RCP-reactive antibodies in terms of both affinity and titer. With regard to bioefficacy, passive immunoneutralization of RCP in pregnant rats by administering purified IgG from either of the antipeptide sera terminated pregnancy. Similarly, active immunization of fertile female rats with the individual peptide analogs curtailed pregnancy. However, HE-20 was more efficient in eliciting higher affinity, longer-lasting, RCP-crossreactive antibodies with consequently more prolonged immunocontraceptive efficacy. PMID:11549280

Subramanian, S; Karande, A A; Adiga, P R



Hindlimb unloading has a greater effect on cortical compared with cancellous bone in mature female rats  

NASA Technical Reports Server (NTRS)

This study was designed to determine the effects of 28 days of hindlimb unloading (HU) on the mature female rat skeleton. In vivo proximal tibia bone mineral density and geometry of HU and cage control (CC) rats were measured with peripheral quantitative computed tomography (pQCT) on days 0 and 28. Postmortem pQCT, histomorphometry, and mechanical testing were performed on tibiae and femora. After 28 days, HU animals had significantly higher daily food consumption (+39%) and lower serum estradiol levels (-49%, P = 0.079) compared with CC. Proximal tibia bone mineral content and cortical bone area significantly declined over 28 days in HU animals (-4.0 and 4.8%, respectively), whereas total and cancellous bone mineral densities were unchanged. HU animals had lower cortical bone formation rates and mineralizing surface at tibial midshaft, whereas differences in similar properties were not detected in cancellous bone of the distal femur. These results suggest that cortical bone, rather than cancellous bone, is more prominently affected by unloading in skeletally mature retired breeder female rats.

Allen, Matthew R.; Bloomfield, Susan A.



Moderate physical exercise attenuates the alterations of feeding behaviour induced by social stress in female rats.  


Epidemiological studies have demonstrated that stress-related disorders, such as the increase on the caloric intake, are twice as common in women as in men, but surprisingly, very few studies have been tested this subject on female experimental animals. Additionally, it has been proposed that regular physical exercise can improve the deleterious effects of stress. Therefore, the present longitudinal study, performed in female rats, aimed to test the influence of chronic stress (ST) imposed by social isolation on the animals' caloric intake and to assess the effect of regular physical exercise of low intensity on this behaviour. In 4 groups of Wistars rats (control sedentary, n = 6; control exercised, n = 6; ST sedentary, n = 6; ST exercised, n = 6), body weight, food intake, abdominal fat weight, adrenal weight, corticosterone metabolites in faeces and plasma insulin levels were measured during the experimental protocol and/or at its end. The results showed that social isolation was not able to modify the amount of abdominal fat and the body weight; however, it promoted significant increases in the corticosterone metabolites and in the amount of caloric intake, which were attenuated in exercised rats. Additionally, exercised groups presented lower levels of fasting insulin than sedentary groups. Therefore, the present study demonstrated that regular physical exercise of low intensity attenuates the corticosterone metabolites and overeating behaviour triggered by social stress. PMID:23740556

Benite-Ribeiro, Sandra Aparecida; Santos, Júlia Matzenbacher Dos; Duarte, José Alberto Ramos



Peripheral injection of sauvagine prevents repeated colorectal distension-induced visceral pain in female rats.  


We investigated the effects of peripheral injection of sauvagine, a CRF2>CRF1 receptor (corticotropin-releasing factor) agonist compared with CRF, on two sets of tonic colorectal distension (CRDs 30, 40, 50 mmHg, 3-min on/off)-induced visceromotor response (VMR) measured as area under the curve (AUC) of abdominal muscle contraction in conscious female rats. Sauvagine (10 or 20 microg/kg, s.c.) abolished the 226.7+/-64.3% and 90.4+/-38.1% increase in AUC to the 2nd CRD compared with the 1st CRD (performed 30 min before) in female Fisher and Sprague-Dawley (SD) rats, respectively. CRF had no effect while the CRF1 antagonist, antalarmin (20 mg/kg, s.c.), alone or with sauvagine, blocked the enhanced response to the 2nd CRD, performed 60 min after the 1st CRD, and reduced further the AUC by 33.5+/-23.3% and 63.5+/-7.2%, respectively in Fisher rats. These data suggest that peripheral CRF2 receptor activation exerts antinociceptive effects on CRD-induced visceral pain, whereas CRF1 contributes to visceral sensitization. PMID:15949637

Million, Mulugeta; Maillot, Céline; Adelson, David A; Nozu, Tsukasa; Gauthier, Ariane; Rivier, Jean; Chrousos, George P; Bayati, Alfred; Mattsson, Hillevi; Taché, Yvette



Oral administration of leaf extracts of Momordica charantia affect reproductive hormones of adult female Wistar rats  

PubMed Central

Objective To determine the effect of graded doses of aqueous leaf extracts of Momordica charantia on fertility hormones of female albino rats. Methods Twenty adult, healthy, female Wistar rats were divided into four groups: low dose (LD), moderate dose (MD) and high dose (HD) groups which received 12.5 g, 25.0 g, 50.0 g of the leaf extract respectively and control group that was given with water ad libatum. Result Estrogen levels reduced by 6.40 nmol/L, 10.80 nmol/L and 28.00 nmol/L in the LD, MD and HD groups respectively while plasma progesterone of rats in the LD, MD and HD groups reduced by 24.20 nmol/L, 40.8 nmol/L and 59.20 nmol/L respectively. Conclusion Our study has shown that the antifertility effect of Momordica charantia is achieved in a dose dependent manner. Hence, cautious use of such medication should be advocated especially when managing couples for infertility. PMID:25183143

Adewale, Osonuga Odusoga; Oduyemi, Osonuga Ifabunmi; Ayokunle, Osonuga



Inner capillary diameter of hypothalamic paraventricular nucleus of female rat increases during lactation  

PubMed Central

Background The role of the endothelial cell (EC) in blood flow regulation within the central nervous system has been little studied. Here, we explored EC participation in morphological changes of the anterior hypothalamic paraventricular nucleus (PVN) microvasculature of female rats at two reproductive stages with different metabolic demand (virginity and lactation). We measured the inner capillary diameter (ICD) of 800 capillaries from either the magnocellular or parvocellular regions. The space occupied by neural (somas, dendrites and axons) and glial, but excluding vascular elements of the neurovascular compartment was also measured in 100-?m2 sample fields of both PVN subdivisions. Results The PVN of both groups of animals showed ICDs that ranged from 3 to 10 microns. The virgin group presented mostly capillaries with small ICD, whereas the lactating females exhibited a significant increment in the percentage of capillaries with larger ICD. The space occupied by the neural and glial elements of the neurovascular compartment did not show changes with lactation. Conclusions Our findings suggest that during lactation the microvasculature of the PVN of female rats undergoes dynamic, transitory changes in blood flow as represented by an increment in the ICD through a self-cytoplasmic volume modification reflected by EC changes. A model of this process is proposed. PMID:23302443



Effects of perinatal ethinyl estradiol exposure in male and female Wistar rats.  


Perinatal exposure to endocrine disrupting chemicals with estrogenic activity can adversely affect reproductive development, but few studies evaluating estrogen-sensitive endpoints have been performed in Wistar rats. Therefore, time-mated Wistar rats (n=10) were gavaged during gestation and lactation with 0, 5, 15 or 50?g/kg bw/day of ethinyl estradiol. This potent estrogen was found to induce an increased number of nipples and reduced ovary weight in female offspring. Malformations of female genitalia were found in young as well as adult offspring, as an increased AGD was seen at birth and a deeper urethral slit length was seen in adulthood. In prepubertal male offspring, estrogen-regulated gene expression in ventral prostate was increased dose-dependently and a decreased ventral prostate weight was seen at 15?g/kg. Female external sexual characteristics and prostate development were found to be targets for exposure to estrogenic compounds and may be of interest in studies on estrogenic environmental compounds. PMID:24036065

Mandrup, Karen Riiber; Jacobsen, Pernille Rosenskjold; Isling, Louise Krag; Axelstad, Marta; Dreisig, Karin; Hadrup, Niels; Vinggaard, Anne Marie; Hass, Ulla; Boberg, Julie



Agmatine reduces ultrasonic vocalization deficits in female rat pups exposed neonatally to ethanol.  


Rat pups, in isolation, produce ultrasonic vocalizations (USVs). These USVs have been used as a diagnostic tool for developmental toxicity. We have shown that neonatal ethanol (ETOH) exposure produces deficits in this behavior. The current study was designed to examine whether agmatine (AG), which binds to imidazoline receptors and modulates n-methyl-d-aspartate receptors (NMDAR), could reduce these deficits. In addition, this study examined critical periods for ETOH's effects on USVs by administering ETOH during either the 1st or 2nd postnatal week. Neonatal rats received intragastric intubations of either ETOH (6g/kg/day), ETOH and AG (6g/kg/day and 20mg/kg/day), AG (20mg/kg/day), or maltose on postnatal days (PND) 1-7 or 8-14. A non-intubated control was also included. Subjects were tested on PND 15. Neonatal ETOH exposure significantly increased the latency to vocalize for females and reduced the rate of USVs in both males and females exposed to ETOH on PND 1-7. Agmatine reduced these deficits, in female but not male pups. Subjects exposed to ETOH on PND 8-14 showed no evidence of abnormal USVs. These findings suggest that there may be gender differences in response to AG following neonatal ETOH exposure and also provide further support that the first neonatal week is a particularly sensitive time for the developmentally toxic effects of ETOH in rodents. PMID:19945529

Wellmann, Kristen; Lewis, Ben; Barron, Susan



[Prenatal stressed female rats develop stable anxious and depressive state in experimental model of post-traumatic stress disorder].  


The effects of immobilization stress from 15th to 19th days of gestation on pathological state development in the model of post-traumatic stress disorder in adult female offspring were studied. The results showed that prenatally stressed female rats as well as control rats demonstrated long-term high anxiety and hypersensitive glucocorticoid feedback in the stress-restress model. Enhanced depressive-like behaviour was found only in prenatally stressed females. The findings were discussed in the light of HPA axis alteration and risk factors for development of post-traumatic stress disorder. PMID:22390074

Ordian, N E; Pivina, S G; Fedotova, Iu O; Rakitskaia, V V



A role for AKAP (A kinase anchoring protein) scaffolding in the loss of a cyclic adenosine 3',5'-monophosphate inhibitory response in late pregnant rat myometrium.  


During pregnancy in the rat, there is a change in the ability of chlorophenylthio (CPT)-cAMP to inhibit myometrial phosphatidylinositide turnover. This is accompanied by a change in the association of proteins with a plasma membrane A kinase anchoring protein (AKAP). Both CPT-cAMP and isoproterenol inhibited oxytocin-stimulated phosphatidylinositide turnover on days 12 through 20 of gestation, whereas neither agent had an effect on day 21. Accompanying this change was a dramatic decrease in the concentration and activity of cAMP-dependent protein kinase [protein kinase A (PKA)] and an increase in the concentration of protein phosphatase 2B (PP2B) in plasma membranes from day 21 compared with day 19 pregnant rats. In contrast, both PKA and PP2B concentrations and activities increased in total myometrial homogenates. Both PKA and PP2B coimmunoprecipitated with an antibody against the 150-kDa AKAP found in rat myometrial plasma membranes. More PKA was associated with AKAP150 on day 19 than on day 21, while the reverse was true for PP2B. Disruption of PKA/AKAP association in day 19 pregnant rat myometrial cells with the specific interaction inhibitor peptide S-Ht31 resulted in the loss of the cAMP-inhibitory effect on phosphatidylinositide turnover. PP2B activity in myometrial homogenates dephosphorylated PLCbeta3, a PKA substrate targeted in the inhibition of Galphaq-stimulated phosphatidylinositide turnover. The dramatic loss of the cAMP-inhibitory effect on day 21 of pregnancy may alter the balance between uterine contraction and relaxation near parturition. The changes in the relative concentrations of PKA and PP2B associated with AKAP150 are consistent with a functional role for AKAP150 scaffolding in the alteration of cellular signaling. PMID:10598575

Dodge, K L; Carr, D W; Yue, C; Sanborn, B M



Prenatal Stress Depresses Immune Function in Rats  

Microsoft Academic Search

KAY, G., N. TARCIC, T. POLTYREV AND M. WEINSTOCK.Prenatal stress depresses immune function in rats.PHYSIOL BEHAV 63(3) 397–402, 1998.—The aim of the present study was to determine the effect of prenatal stress on immune function in rats. Pregnant rats were stressed by noise and light, three times weekly throughout pregnancy. Experiments were performed on male and female offspring aged 2

G Kay; N Tarcic; T Poltyrev; M Weinstock



Effect of coffee oil and its unsaponifiable fraction on plasma cholesterol level in female rats.  


The present study was conducted to identify the cholesterol-raising factor in coffee oil besides the other two well-known diterpenes, cafestol and kahweol. Female rats fed coffee oil for 4 weeks showed significantly higher level of plasma cholesterol (P < 0.01) and triacylglycerols (P < 0.01). Feeding unsaponifiable lipids of coffee oil caused significant decrease in plasma cholesterol; however, increase in triacylglycerol was observed. Rats given beta-sitosterol showed increase in plasma triacylglecerol and decrease in cholesterol levels, an effect similar to that observed with unsaponifiable lipids. beta-sitosterol is the major constituent of unsaponifiable lipids of the coffee oil. These results show that cafestol and kahweol diterpene alcohols are not the only cholesterol-raising factors in coffee oil. PMID:10616649

al-Kanhal, M A; Ahmed, F; Arif, Z



Tacrolimus and sirolimus have distinct effects on insulin signaling in male and female rats.  


Although the contribution of the immunosuppressants tacrolimus (TAC) and sirolimus (SIR) to the development of posttransplant diabetes mellitus (PTDM) are being increasingly recognized, the mechanisms of immunosuppressant-induced hyperglycemia are unclear. SIR induces insulin resistance predominantly, but is associated with ?-cell dysfunction in rodents. TAC affects islet function but is associated with worsening insulin sensitivity in a few, and improvement in some, clinical studies. We sought to clarify the contributions of TAC and SIR to insulin resistance and islet function. Four groups of male and female Sprague-Dawley rats received TAC, SIR, TAC and SIR, or control for 2 weeks. All rats were administered an oral glucose challenge at the end of treatment. Half the groups were sacrificed 10 minutes after administration of regular insulin whereas the other half did not receive insulin before sacrifice. Liver, pancreas, fat, and muscle were harvested subsequently. Quantification of Western blots revealed that SIR and TAC plus SIR suppressed the phospho-Akt (pAkt)-to-Akt ratios in liver, muscle, and fat compared with control, regardless of sex. TAC alone did not impair the pAkt-to-Akt ratios in any of the tissues in male and female rats. ?-Cell mass was reduced significantly after TAC treatment in male rats. SIR did not affect ?-cell mass, regardless of sex. Our study demonstrated very clearly that SIR impairs insulin signaling, without any effect on ?-cell mass, and TAC does not impair insulin signaling but reduces ?-cell mass. Our efforts are key to understanding the mechanisms of immunosuppressant-induced hyperglycemia and to tailoring treatments for PTDM. PMID:24361102

Shivaswamy, Vijay; Bennett, Robert G; Clure, Cara C; Ottemann, Brendan; Davis, John S; Larsen, Jennifer L; Hamel, Frederick G



The effects of iridium on the renal function of female Wistar rats.  


Despite the widespread use of iridium (Ir) in catalytic converters for improved capacity for reducing carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NO(x)) emissions, there is a lack of studies that have assessed possible toxicological hazards of exposure to Ir. The present investigation indicates that female Wistar rats exposed to Ir in the drinking water for 90 days displayed renal toxicity based on the elevated urinary retinol binding protein (RBP) and albumin. The RBP was more sensitive to albumin, showing significant increases at 0.01 mg/L. PMID:21764451

Iavicoli, Ivo; Fontana, Luca; Marinaccio, Alessandro; Alimonti, Alessandro; Pino, Anna; Bergamaschi, Antonio; Calabrese, Edward J



Overweight female rats selectively breed for low aerobic capacity exhibit increased myocardial fibrosis and diastolic dysfunction  

PubMed Central

The statistical association between endurance exercise capacity and cardiovascular disease suggests that impaired aerobic metabolism underlies the cardiovascular disease risk in men and women. To explore this connection, we applied divergent artificial selection in rats to develop low-capacity runner (LCR) and high-capacity runner (HCR) rats and found that disease risks segregated strongly with low running capacity. Here, we tested if inborn low aerobic capacity promotes differential sex-related cardiovascular effects. Compared with HCR males (HCR-M), LCR males (LCR-M) were overweight by 34% and had heavier retroperitoneal, epididymal, and omental fat pads; LCR females (LCR-F) were 20% heavier than HCR females (HCR-F), and their retroperitoneal, but not perireproductive or omental, fat pads were heavier as well. Unlike HCR-M, blood pressure was elevated in LCR-M, and this was accompanied by left ventricular (LV) hypertrophy. Like HCR-F, LCR-F exhibited normal blood pressure and LV weight as well as increased spontaneous cage activity compared with males. Despite normal blood pressures, LCR-F exhibited increased myocardial interstitial fibrosis and diastolic dysfunction, as indicated by increased LV stiffness, a decrease in the initial filling rate, and an increase in diastolic relaxation time. Although females exhibited increased arterial stiffness, ejection fraction was normal. Increased interstitial fibrosis and diastolic dysfunction in LCR-F was accompanied by the lowest protein levels of phosphorylated AMP-actived protein kinase [phospho-AMPK (Thr172)] and silent information regulator 1. Thus, the combination of risk factors, including female sex, intrinsic low aerobic capacity, and overweightness, promote myocardial stiffness/fibrosis sufficient to induce diastolic dysfunction in the absence of hypertension and LV hypertrophy. PMID:22345570

Johnson, Megan S.; Ma, Lixin; Pulakat, Lakshmi; Mugerfeld, Irina; Hayden, Melvin R.; Garro, Mona; Knight, William; Britton, Steven L.; Koch, Lauren G.; Sowers, James R.



Age and adolescent social stress effects on fear extinction in female rats.  


We previously observed that social instability stress (SS: daily 1?h isolation and change of cage partners for 16 days) in adolescence, but not in adulthood, decreased context and cue memory after fear conditioning in male rats. Effects of stress are typically sex-specific, and so here we investigated adolescent and adult SS effects in females on the strength of acquired contextual and cued fear conditioning, as well as extinction learning, beginning either the day after the stress procedure or four weeks later. For SS in adolescence, SS females spent more time freezing (fear measure) during extinction than did controls, whereas SS in adulthood had no effect on any measure of fear conditioning. The results also indicated an effect of age: females in late adolescence show more rapid extinction of cue and better memory of extinction of context compared to adult females, which may indicate resilience to acute footshock in adolescence. Thus fear circuitry continues to mature into late adolescence, which may underlie the heightened plasticity in response to chronic stressors of adolescents compared to adults. PMID:23992540

McCormick, C M; Mongillo, D L; Simone, J J



Cholesterol and Perhaps Estradiol Protect Against Corticosterone-Induced Hippocampal CA3 Dendritic Retraction in Gonadectomized Female and Male Rats  

PubMed Central

Chronic stress or glucocorticoid exposure simplifies hippocampal CA3 apical dendritic arbors in male rats. In contrast to males, chronic stress either reduces CA3 basal branching or exerts no observable morphological effects in gonadally intact female rats. Under conditions that females display stress-induced CA3 dendritic retraction, such as following ovariectomy, chronic exposure to 17?-estradiol or cholesterol can negate these changes. Whether glucocorticoids produce CA3 dendritic retraction in ovariectomized females and whether neuroprotection from 17?-estradiol or cholesterol is sex-specific remains unknown. The current study examined the effects of chronic glucocorticoid exposure, in conjunction with 17?-estradiol or cholesterol administration, on hippocampal CA3 dendritic complexity. Adult male and female Sprague-Dawley rats were gonadectomized and implanted with 25% 17?-estradiol in cholesterol, 100% cholesterol, or blank Silastic capsules. Rats were then assigned to either a 21-day corticosterone (CORT) drink (400µg/mL CORT, 2.4% ethanol in tap water) or tap water (Tap, 2.4% ethanol in tap water) treatment. Brains were processed for Golgi staining, and hippocampal CA3 dendritic architecture was quantified. Results showed 21-day CORT administration reduced hippocampal CA3 apical dendritic branch points, CA3 apical dendritic length, body weight gain, and adrenal weights compared to male and female control counterparts. Furthermore, male and female rats implanted with Silastic capsules containing cholesterol or 25% 17?-estradiol in cholesterol were protected from CORT-induced CA3 apical dendritic branch reduction. No effects were observed in the CA3 basal dendritic arbors. The present results demonstrate that CORT produces hippocampal CA3 dendritic retraction in gonadectomized male and female rats and that cholesterol and 25% 17?-estradiol in cholesterol prevent this dendritic simplification. PMID:23618757

Ortiz, J. Bryce; McLaughlin, Katie J.; Hamilton, Gillian F.; Baran, Sarah E.; Campbell, Alyssa N.; Conrad, Cheryl D.



Adolescent pre-treatment with oxytocin protects against adult methamphetamine-seeking behavior in female rats.  


The neuropeptide oxytocin (OT), given acutely, reduces self-administration of the psychostimulant drug methamphetamine (METH). Additionally, chronic OT administration to adolescent rats reduces levels of alcohol consumption in adulthood, suggesting developmental neuroplasticity in the OT system relevant to addiction-related behaviors. Here, we examined whether OT exposure during adolescence might subsequently inhibit METH self-administration in adulthood. Female Sprague-Dawley rats were administered vehicle or OT (1?mg/kg, i.p.) once daily from postnatal days (PND) 28 to 37 (adolescence). At PND 62 (adulthood), rats were trained to self-administer METH (intravenous, i.v.) in daily 2-hour sessions for 10 days under a fixed ratio 1 (FR1) reinforcement schedule, followed by determination of dose-response functions (0.01-0.3?mg/kg/infusion, i.v.) under both FR1 and progressive ratio (PR) schedules of reinforcement. Responding was then extinguished, and relapse to METH-seeking behavior assessed following priming doses of non-contingent METH (0.1-1?mg/kg, i.p.). Finally, plasma was collected to determine pre-treatment effects on OT and corticosterone levels. Results showed that OT pre-treatment did not significantly inhibit the acquisition of METH self-administration or FR1 responding. However, rats pre-treated with OT responded significantly less for METH under a PR reinforcement schedule, and showed reduced METH-primed reinstatement with the 1?mg/kg prime. Plasma OT levels were also significantly higher in OT pre-treated rats. These results confirm earlier observations that adolescent OT exposure can subtly, yet significantly, inhibit addiction-relevant behaviors in adulthood. PMID:25402719

Hicks, Callum; Cornish, Jennifer L; Baracz, Sarah J; Suraev, Anastasia; McGregor, Iain S



Renoprotective effect of hydroalcoholic extract of Rheum ribes root in diabetic female rats  

PubMed Central

Objective: Medical plants, as rich sources of natural antioxidants with antidiabetic effects, are used worldwide to diminish a variety of symptoms and many diseases. R. ribes L., which belongs to the family of polygonaceae, can provide symptomatic relief and assist in the prevention of the secondary complications of the diabetes. Material and Methods: 36 female adult rats were randomly divided into 6 groups of 6. Normal Control groups treated with normal saline. Positive control groups treated with hydroalcohlic extract of R. ribes root (150 mg/kg) daily by gavages for 4 consecutive weeks. Diabetes was inducedby injection of 120 mg/kg alloxan monohydrate intraperitoneally. Two diabetic groups were treated with different doses of R. ribes root extract. The sixth diabetic groups were treated with glibenclamide (0.6 mg/kg). At the end of 28 days, blood samples were collected and their kidney tissues were processed for light microscopy. Results: The results showed that hydro-alcoholic extract of R. ribes decreased the level of glucose, cholesterol, triglyceride, urea and creatinine in diabetic rats (p<0.05) in compared with diabetic rats, while the level of HDL increased at the same group (p<0.05). Histopathological changes of kidney samples were comparable with respective control. In diabetic rats, kidney sections showed atrophy of glomerular capillaries with increased Bowman's space and acute tubular necrosis. The groups that were treated with R. ribes root were improved towards normal condition. Conclusion: It is interesting to note that hydroalcohlic extract of R. ribes root improves renal dysfunction in alloxan-induced diabetic rats through controlling blood glucose and renal protective effects. PMID:25386403

Hamzeh, Shokri; Farokhi, Farah; Heydari, Reza; Manaffar, Ramin




EPA Science Inventory

Bromodichloromethane (BDCM), a trihalomethane, is a by-product of the chlorination of drinking water. In an epidemiological study, consumption of drinking water with high levels of BDCM was associated with an increased risk of spontaneous abortion in pregnant women (Waller et al....


Maternal separation exaggerates spontaneous recovery of extinguished contextual fear in adult female rats.  


Early life stress increases the risk of posttraumatic stress disorders (PTSD). Patients with PTSD show impaired extinction of traumatic memory, and in women, this occurs more often when PTSD is preceded by child trauma. However, it is still unclear how early life stress accounts for extinction impairment. Here, we studied the effects of maternal separation (MS, postnatal day 2 to 14) on contextual fear extinction in adult female rats. Additionally, to examine changes in synaptic function affected by MS, we measured long-term potentiation (LTP) in prefrontal cortex and hippocampus in vitro, both of which have been implicated in fear extinction. We found that adult female rats had been subjected to MS exhibited significant spontaneous recovery of fear to the extinguished context. Furthermore, MS exposure resulted in LTP impairment in both infralimbic prefrontal cortex layer 2/3-layer 5 and hippocampal SC-CA1 pathways. Interestingly, no obvious effects of MS on contextual fear conditioning, fear recall as well as extinction training and recall were observed. Innate fear in the elevated plus maze or open field test remained nearly unaffected. These findings provided the first evidence that MS may exaggerate spontaneous recovery after contextual fear extinction, for which LTP impairment in the medial prefrontal cortex and hippocampus may be responsible, thereby possibly leading to impaired extinction associated with PTSD. PMID:24746487

Xiong, Gui-Jing; Yang, Yuan; Wang, Li-Ping; Xu, Lin; Mao, Rong-Rong



Early handling effect on female rat spatial and non-spatial learning and memory.  


This study aims at providing an insight into early handling procedures on learning and memory performance in adult female rats. Early handling procedures were started on post-natal day 2 until 21, and consisted in 15 min, daily separations of the dams from their litters. Assessment of declarative memory was carried out in the novel-object recognition task; spatial learning, reference- and working memory were evaluated in the Morris water maze (MWM). Our results indicate that early handling induced an enhancement in: (1) declarative memory, in the object recognition task, both at 1h and 24h intervals; (2) reference memory in the probe test and working memory and behavioral flexibility in the "single-trial and four-trial place learning paradigm" of the MWM. Short-term separation by increasing maternal care causes a dampening in HPA axis response in the pups. A modulated activation of the stress response may help to protect brain structures, involved in cognitive function. In conclusion, this study shows the long-term effects of a brief maternal separation in enhancing object recognition-, spatial reference- and working memory in female rats, remarking the impact of early environmental experiences and the consequent maternal care on the behavioral adaptive mechanisms in adulthood. PMID:24216081

Plescia, Fulvio; Marino, Rosa A M; Navarra, Michele; Gambino, Giuditta; Brancato, Anna; Sardo, Pierangelo; Cannizzaro, Carla



Nonproliferative and Proliferative Lesions of the Rat and Mouse Female Reproductive System  

PubMed Central

The INHAND (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) Project ( is a joint initiative of the Societies of Toxicological Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP) and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative lesions in laboratory animals. The purpose of this publication is to provide a standardized nomenclature for classifying microscopic lesions observed in the female reproductive tract of laboratory rats and mice, with color photomicrographs illustrating examples of some lesions. The standardized nomenclature presented in this document is also available electronically on the internet ( Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous and aging lesions as well as lesions induced by exposure to test materials. There is also a section on normal cyclical changes observed in the ovary, uterus, cervix and vagina to compare normal physiological changes with pathological lesions. A widely accepted and utilized international harmonization of nomenclature for female reproductive tract lesions in laboratory animals will decrease confusion among regulatory and scientific research organizations in different countries and provide a common language to increase and enrich international exchanges of information among toxicologists and pathologists. PMID:25516636

Dixon, Darlene; Alison, Roger; Bach, Ute; Colman, Karyn; Foley, George L.; Harleman, Johannes H.; Haworth, Richard; Herbert, Ronald; Heuser, Anke; Long, Gerald; Mirsky, Michael; Regan, Karen; Van Esch, Eric; Westwood, F. Russell; Vidal, Justin; Yoshida, Midori



Restoring and maintaining bone in osteopenic female rat skeleton: I. Changes in bone mass and structure  

NASA Technical Reports Server (NTRS)

This experiment contains the crucial data for the lose, restore, and maintain (LRM) concept, a practical approach for reversing existing osteoporosis. The LRM concept uses anabolic agents to restore bone mass and architecture (+ phase) and then switches to an agent with the established ability to maintain bone mass, to keep the new bone (+/- phase). The purpose of this study was to learn whether switching to an agent known chiefly for its ability to maintain existing bone mass preserves new bone induced by PGE2 in osteopenic, estrogen-depleted rats. The current study had three phases, the bone loss (-), restore (+), and maintain (+/-) phases. We ovariectomized (OX) or sham ovariectomized (sham-OX) 5.5-month-old female rats (- phase). The OX rats were treated 5 months postovariectomy with 1-6 mg PGE2 per kg/day for 75 days to restore lost cancellous bone mass (+ phase), and then PGE2 treatment was stopped and treatment began with 1 or 5 micrograms/kg of risedronate, a bisphosphonate, twice a week for 60 days (+/- phase). During the loss (-) phase, the cancellous bone volume of the proximal tibial metaphysis in the OX rat fell to 19% of initial and 30% of age-matched control levels. During the restore (+) phase, the cancellous bone volume in OX rats doubled. When PGE2 treatment was stopped, however, and no special maintenance efforts were made during the maintain (+/-) phase, the PGE2-induced cancellous bone disappeared. In contrast, the PGE2-induced cancellous bone persisted when the PGE2 treatment was followed by either a 1 or 5 micrograms treatment of risedronate per kg given twice a week for 60 days during the maintain (+/-) phase. The tibial shaft demonstrated very little cortical bone loss during the loss (-) phase in OX rats. The tibial shaft cortical bone fell some 8%. During the restore (+) phase, new cortical bone in OX rats increased by 22%. When PGE2 treatment was stopped and nothing was given during the maintain (+/-) phase, however, all but the PGE2-induced subperiosteal bone disappeared. In contrast, when PGE2 treatment was stopped and 1 micron risedronate per kg twice a week for 60 days was administered during the maintenance (+/-) phase, the PGE2-induced subperiosteal bone and some of the subendocortical bone and marrow trabeculae persisted.(ABSTRACT TRUNCATED AT 400 WORDS).

Tang, L. Y.; Jee, W. S.; Ke, H. Z.; Kimmel, D. B.



Significant role of female sex hormones in cardiac myofilament activation in angiotensin II-mediated hypertensive rats.  


Ovariectomy leads to suppression of cardiac myofilament activation in healthy rats implicating the physiological essence of female sex hormones on myocardial contraction. However, the possible function of these hormones during pathologically induced myofilament adaptation is not known. In this study, sham-operated and ovariectomized female rats were chronically exposed to angiotensin II (AII), which has been shown to cause myocardial adaptation. In the shams, AII induced cardiac adaptation by increasing myofilament Ca(2+) sensitivity. Interestingly, this hypersensitivity was further enhanced in AII-infused ovariectomized rats. Ovariectomy increased the phosphorylation levels of cardiac tropomyosin, which may underlie the mechanism of hypersensitivity. On the other hand, AII infusion did not alter maximal tension that was suppressed after ovariectomy. This finding coincided with a comparable increase in ?-isoform of myosin heavy chains in both ovariectomized groups. Together, it is conceivable that female sex hormones serve as predominant factors that regulate cardiac myofilament activation. Furthermore, they may prevent stress-induced myofilament maladaptation. PMID:24777837

Pandit, Sulaksana; Woranush, Warunya; Wattanapermpool, Jonggonnee; Bupha-Intr, Tepmanas



Ultra-structural morphological abnormalities of the urinary bladder in streptozotocin-induced diabetic female rats.  


The objective of this study was to evaluate the ultra-structural changes in the urinary bladder of diabetic rats in relation to disease duration since the morphological bases of diabetes-induced bladder dysfunction are poorly understood. Urinary bladders were examined chronologically by electron microscopy in a female Wistar-rat model of streptozotocin-induced diabetes mellitus and compared to control samples. Numerous dark mitochondria with swollen cristae and electron lucent, large, calcified and degenerated mitochondria were observed first in the urothelium. Intraepithelial capillaries surrounded by thick collagen were also present. Gap junctions between myocytes were interrupted or extensively widened with reduced mitochondria and caveolae. Collagen accumulation, degenerated nerve fibres and myelin bodies were seen between myocytes with increased collagen content and frequent mast cells, phagocytes and lymphocyte aggregates in the stroma. All ultra-structural lesions became augmented with longer duration of diabetes. Diabetes induces time-dependent pathologic changes in the urinary bladder of rats that might account for bladder dysfunction. PMID:16021327

Rizk, Diaa E E; Padmanabhan, Rengasamy K; Tariq, Saeed; Shafiullah, Mohamed; Ahmed, Ijaz



Imidacloprid induced histological and biochemical alterations in liver of female albino rats.  


Imidacloprid is a neonicotinoid insecticide being used extensively for crop protection and pet flea control programmes. The effect of repeated oral administration of two doses of imidcloprid (1/10th and 1/50th of LD50 of imidacloprid) on liver of female albino rat was assessed. Histological examination of liver revealed that imidacloprid (1/10th of LD50) treatment resulted in dilations of central vein and sinusoids between hepatocytes however imidacloprid (1/50th of LD50) treatment did not induce histopathological changes in liver. Non significant decrease in alkaline phosphatase (AKP) activity was observed in imidacloprid treated rats. Liver aspartate aminotransferase level showed significant increase in higher dose of imidacloprid. Additionally, significant increases in plasma levels of aspatate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (AKP) were observed in the treated rats. The results suggest that the higher doses of imidacloprid at 1/10th of LD50 is hepatotoxic as compared to lower dose of 1/50th of LD50 of imidacloprid. PMID:24238282

Toor, Harmandeep Kaur; Sangha, Gurinder Kaur; Khera, Kuldeep Singh



Molecular Mechanisms Underlying the Rapid Arrhythmogenic Action of Bisphenol A in Female Rat Hearts  

PubMed Central

Previously we showed that bisphenol A (BPA), an environmental estrogenic endocrine disruptor, rapidly altered Ca2+ handling and promoted arrhythmias in female rat hearts. The underlying molecular mechanism was not known. Here we examined the cardiac-specific signaling mechanism mediating the rapid impact of low-dose BPA in female rat ventricular myocytes. We showed that protein kinase A (PKA) and Ca2+/CaM-dependent protein kinase II (CAMKII) signaling pathways are the two major pathways activated by BPA. Exposure to 1 nM BPA rapidly increased production of cAMP and rapidly but transiently increased the phosphorylation of the ryanodine receptors by PKA but not by CAMKII. BPA also rapidly increased the phosphorylation of phospholamban (PLN), a key regulator protein of sarcoplasmic reticulum Ca2+ reuptake, by CAMKII but not PKA. The increase in CAMKII phosphorylation of PLN was mediated by phospholipase C and inositol trisphosphate receptor-mediated Ca2+ release, likely from the endoplasmic reticulum Ca2+ storage. These two pathways are likely localized, impacting only their respective target proteins. The rapid impacts of BPA on ryanodine receptors and PLN phosphorylation were mediated by estrogen receptor-? but not estrogen receptor-?. BPA's rapid signaling in cardiac myocytes did not involve activation of ERK1/2. Functional analysis showed that PKA but not CAMKII activation contributed to BPA-induced sarcoplasmic reticulum Ca2+ leak, and both PKA and CAMKII were necessary contributors to the stimulatory effect of BPA on arrhythmogenesis. These results provide mechanistic insight into BPA's rapid proarrhythmic actions in female cardiac myocytes and contribute to the assessment of the consequence and potential cardiac toxicity of BPA exposure. PMID:24140712

Gao, Xiaoqian; Liang, Qian; Chen, Yamei



Reproductive Experience Alters Prolactin Receptor Expression in Mammary and Hepatic Tissues in Female Rats1  

PubMed Central

Recent studies have reported that reproductive experience in female rats alters prolactin (PRL) receptor gene expression in the brain as well as neural sensitivity to PRL. Given PRL's actions in nonneural tissues, that is, mammary tissue and liver, it was asked whether reproductive experience may also alter prolactin receptor (Prlr) gene expression in these tissues. Groups of age-matched female rats were generated with varying reproductive histories. Separate groups of primiparous (first lactation) and multiparous (second lactation) had mammary tissue and liver samples collected on Day 3 or 10 of lactation. A fifth group raised one litter to weaning and then resumed estrous cyclicity. This group and a final group of age-matched, virgin controls were killed on diestrus. Tissue was processed by quantitative PCR for expression rates of the long and short forms of Prlr mRNA as well as casein beta mRNA (mammary tissue only). Western blots were performed to quantify receptor protein content. Multiple lactations as well as lactation itself resulted in alterations in Prlr expression. Prlr gene expression in mammary tissue was increased in primiparous mothers compared with that in multiparous dams, whereas in the liver, Prlr expression was reduced during an initial lactation. In contrast, PRLR protein levels declined during lactation in mammary, but not hepatic, tissues. Overall, the results demonstrate that the prolactin receptor system is altered in nonneural tissues as a result of the female's reproductive history. The findings are discussed in the context of milk and bile production and PRL's possible role in breast cancer. PMID:21508351

Bridges, Robert S.; Scanlan, Victoria F.; Lee, Jong-O; Byrnes, Elizabeth M.



Hemolytic anemia, thrombosis, and infarction in male and female F344 rats following gavage exposure to 2-butoxyethanol.  


2-butoxyethanol (BE; ethylene glycol monobutyl ether) is used extensively in the manufacture of a wide range of domestic and industrial products which may result in human exposure and toxicity. BE causes severe hemolytic anemia in male and female rats and mice. In a recent report, female F344 rats exposed to 500 ppm BE by inhalation and sacrificed moribund on day 4 of treatment exhibited disseminated thrombosis associated with infarction in several organs. In contrast, no such lesions were observed in male rats similarly exposed to BE. Additional studies were therefore undertaken to compare the effects of BE in rats of both sexes. Rats received 250 mg BE/kg/day by gavage for 1, 2 or 3 days and were sacrificed 24 or 48 hr after the last dose. Control rats received 5 ml/kg water. Progressive time-dependent hemolytic anemia--macrocytic, hypochromic, and regenerative--was observed in both sexes of rats exposed to BE. Additionally, BE caused significant morphological changes in erythrocytes, first observed 24 hr after a single dose, including stomatocytosis, macrocytosis with moderate rouleaux formation, and spherocytosis. These morphological changes became progressively more severe as BE dosing continued and included the occasional occurrence of schistocytes and ghost cells, rouleaux formation in rats of both sexes, and an increased number of red blood cells with micronuclei in female rats. Overall, the progression of hemolytic anemia and morphological changes as a function of the number of days of exposure varied with gender and suggested a faster onset of hemolysis in female rats. The range of BE-related histopathological changes noted in both sexes was comparable; however, while these lesions were observed in female rats following a single dose, similar effects were first observed in males after 3 consecutive days of exposure to BE. Pathological changes involved disseminated thrombosis in the lungs, nasal submucosa, eyes, liver, heart, bones and teeth, with evidence of infarction in the heart, eyes, teeth and bones. Hemoglobinuric nephrosis and splenic extramedullary hematopoiesis were also noted. An apparent correlation between the severity of hemolytic anemia and subsequent disseminated thrombosis in BE-treated rats is proposed. Thrombosis may be related to intravascular hemolysis, which could be triggered by procoagulant release and/or alterations in erythrocyte morphology, as well as increased rigidity. PMID:11484844

Ghanayem, B I; Long, P H; Ward, S M; Chanas, B; Nyska, M; Nyska, A



Effects of developmental methylphenidate (MPH) treatment on monoamine neurochemistry of male and female rats.  


Attention Deficit Hyperactivity Disorder (ADHD) is estimated to affect 4-5% of the adult human population (Kessler et al., 2006; Willcutt, 2012). Often prescribed to attenuate ADHD symptoms (Nair and Moss, 2009), methylphenidate hydrochloride (MPH) can have substantial positive effects. However, there is a paucity of literature regarding its use during pregnancy. Thus, adult women with ADHD face a difficult decision when contemplating pregnancy. In this study, pregnant Sprague-Dawley rats were orally treated a total of 0 (water), 6 (low), 18 (medium), or 42 (high) mg MPH/kg body weight/day (divided into three doses) on gestational days 6-21 (i.e., the low dose received 2 mg MPH/kg body weight 3×/day). Offspring were orally treated with the same daily dose as their dam (divided into two doses) on postnatal days (PNDs) 1-21. One offspring/sex/litter was sacrificed at PND 22 or PND 104 (n=6-7/age/sex/treatment group) and the striatum was quickly dissected and frozen. High Performance Liquid Chromatography (HPLC) coupled to a Photo Diode Array detector (PDA) was used to analyze monoamine content in the striatum of one side while a sandwich ELISA was used to analyze tyrosine hydroxylase (TH) from the other side. Age significantly affected monoamine and metabolite content as well as turnover ratios (i.e., DA, DOPAC, HVA, DOPAC/DA, HVA/DA, 5-HT and 5-HIAA); however, there were no significant effects of sex. Adult rats of the low MPH group had higher DA levels than control adults (p<0.05). At both ages, subjects of the low MPH group had higher TH levels than controls (p<0.05), although neither effect (i.e., higher DA or TH levels) exhibited an apparent dose-response. PND 22 subjects of the high MPH treatment group had higher ratios of HVA/DA and DOPAC/DA than same-age control subjects (p<0.05). The increased TH levels of the low MPH group may be related to the increased DA levels of adult rats. While developmental MPH treatment appears to have some effects on monoamine system development, further studies are required to determine if these alterations manifest as functional changes in behavior. PMID:25132048

Panos, John J; O'Callaghan, James P; Miller, Diane B; Ferguson, Sherry A



Comparison of the antinociceptive response to morphine and morphine-like compounds in male and female Sprague-Dawley rats.  


Male rats are more sensitive to the antinociceptive effects of morphine than female rats. This difference is seen across several rat strains using a variety of nociceptive stimuli. However, the literature in regard to sex differences in antinociceptive responses to mu-opioids other than morphine is less consistent. The present study was designed to examine whether there is a structure-activity rationale that determines which mu-opioids will show a differential antinociceptive response between male and female rats. A series of morphinans closely related in structure to morphine, namely, codeine, heroin, hydrocodone, hydromorphone, oxymorphone, and oxycodone, were examined for their antinociceptive activity in male and female Sprague-Dawley rats and compared with the structurally unrelated mu-opioid agonists methadone and fentanyl. Antinociception was measured by the warm-water tail-withdrawal assay. The results show that morphine is more potent in males compared with females > hydromorphone = hydrocodone = oxymorphone, but there was no observable sex difference in the antinociceptive potency of codeine, heroin, oxycodone, methadone, or fentanyl. The potency to stimulate guanosine 5'-O-(3-[35 S]thio)triphosphate ([35S]GTPgammaS) binding and binding affinity of the various morphinans was compared in rat glioma C6 cells expressing the rat mu-opioid receptor; relative efficacy was also compared by stimulation of [35S]GTPgammaS binding in slices of rat brain thalamus. The presence of a sex difference in antinociceptive responsiveness was not related to drug potency, efficacy, or affinity. Consequently, it is likely that differential metabolism of the opioid, possibly by glucuronidation, determines the presence or absence of a sex difference. PMID:16291875

Peckham, Elizabeth M; Traynor, John R



An inhalation reproductive toxicity study of octamethylcyclotetrasiloxane (D4) in female rats using multiple and single day exposure regimens.  


Octamethylcyclotetrasiloxane (D(4)) has been shown to have effects on the female rat reproductive cycle. This study evaluated the phase of the female rat reproductive cycle affected by D(4) using a study design that allowed the complete female reproductive cycle, as well as phases of the cycle, from pre-mating through gestation, to be evaluated. Rats were exposed via whole body vapor inhalation up to 700 ppm D(4) during the overall phase (28 days prior to mating through gestation day (GD) 19), the ovarian phase (31-3 days prior to mating), the fertilization phase (3 days prior to the start of mating through gestation day 3), and the implantation phase (GD 2-GD 5) of the reproductive cycle. D(4) was associated with decreases in implantation sites and litter size in the overall and fertilization phases, but not in the ovarian or implantation phases. In order to further define the sensitive period for D(4) exposure, additional groups of rats were exposed on single days. A single 6h exposure to D(4) on the day prior to mating resulted in a significant reduction in fertility. These data indicate that there is a very narrow window, around the time of ovulation and fertilization, for D(4) to exert effects on the reproductive cycle of the female rat. Subsequent research, reported elsewhere, has elucidated the mode of action and assessed its potential relevance to humans. PMID:17254748

Meeks, Robert G; Stump, Donald G; Siddiqui, Waheed H; Holson, Joseph F; Plotzke, Kathleen P; Reynolds, Vincent L



Site-dependent modulating effects of conjugated fatty acids from safflower oil in a rat two-stage carcinogenesis model in female Sprague–Dawley rats  

Microsoft Academic Search

Modifying effects of dietary administration of conjugated fatty acids from safflower oil (CFA-S), rich in conjugated linoleic acid, on major organs were examined in the post-initiation stage of a two-stage carcinogenesis model in female rats. Groups of 21 or 22 F344 female rats were treated sequentially with 2,2?-dihydroxy-di-n-propylnitosamine (intragastrically, i.g.), 7,12-dimethylbenz[a]anthracene (i.g.), 1,2-dimethylhydrazine (subcutaneously) and N-butyl-N-(4-hydroxybutyl)nitrosamine (in drinking water) during

Naoya Kimoto; Masao Hirose; Mitsuru Futakuchi; Toshio Iwata; Masaaki Kasai; Tomoyuki Shirai



Antiovulatory and abortifacient effects of Areca catechu (betel nut) in female rats  

PubMed Central

Objectives: To study the antiovulatory and abortifacient effects of ethanolic extract of Areca catechu in female rats. Materials and Methods: For antiovulatory effect, ethanolic extract of A. catechu at 100 and 300 mg/kg doses was administered orally for 15 days. Vaginal smears were examined daily microscopically for estrus cycle. Rats were sacrificed on 16th day. Ovarian weight, cholesterol estimation, and histopathological studies were done. Abortifacient activity was studied in rats at 100 and 300 mg/kg doses administered orally from 6th to 15th day of pregnancy. Rats were laparotomised on 19th day. The number of implantation sites and live fetuses were observed in both horns of the uterus. Results: The extract of A. catechu showed a significant decrease in the duration of estrus at 100 mg/kg (P = 0.015) and 300 mg/kg doses (P = 0.002) as compared with control. Metestrus phase was also significantly reduced at 100 mg/kg (P = 0.024) and 300 mg/kg doses (P = 0.002). There was a significant increase in proestrus (P < 0.001) phase. However, diestrus phase was unchanged. Histopathological study of the ovaries showed mainly primordial, primary, and secondary follicles in the test groups as compared to control. There was also a significant (P = 0.002) decrease in ovarian weight and a significant (P = 0.021) increase in ovarian cholesterol level at 100 mg/kg dose. In the study to evaluate abortifacient effect, the mean percentage of abortion with 100 and 300 mg/kg doses were 75.5% and 72.22%, respectively, which was significantly (P = 0.008 and P = 0.006, respectively) increased when compared with control. Conclusion: The ethanolic extract of A. catechu at doses of 100 and 300 mg/kg has antiovulatory and abortifacient effects. PMID:21206624

Shrestha, Jyoti; Shanbhag, Tara; Shenoy, Smita; Amuthan, Arul; Prabhu, Krishnananda; Sharma, Stuti; Banerjee, Samik; Kafle, Sajala



Role of Mas receptor in renal blood flow response to angiotensin (1-7) in male and female rats.  


Epidemiologic and clinical studies have shown that progression of renal disease in male is faster than that in female. However, the exact mechanisms are not well recognized. Angiotensin (1-7) (Ang 1-7) receptor, called "Mas", is an element in the depressor arm of renin angiotensin system (RAS), and its expression is enhanced in females. We test the hypothesis that Mas receptor (MasR) blockade (A779) attenuates renal blood flow (RBF) in response to infusion of graded doses of Ang 1-7 in female rats. Male and female Wistar rats were anesthetized and catheterized. Then, the mean arterial pressure (MAP), RBF, and controlled renal perfusion pressure (RPP) responses to infusion of graded doses of Ang 1-7 (100-1000 ng/kg/min i.v.) with and without A779 were measured in the animals. Basal MAP, RPP, RBF, and renal vascular resistance (RVR) were not significantly different between the two groups. After Ang 1-7 administration, RPP was controlled at a constant level. However, RBF increased in a dose-related manner in response to Ang 1-7 infusion in both male and female rats (Pdose<0.0001), but masR blockade significantly attenuated this response only in female (Pgroup=0.04) and not male (Pgroup=0.23). In addition, A779 increased the RBF response to Ang 1-7 to a greater extent. This is while the increase in male was not significant when compared with that in female (Pgender=0.08). RVR response to Ang 1-7 was insignificantly attenuated by A779 in both genders. The masR differently regulated RBF response to Ang 1-7 in the two genders, and the effect was greater in female rats. The masR may be a target for improvement of kidney circulation in renal diseases. PMID:24968411

Nematbakhsh, Mehdi; Safari, Tahereh



Soyo-san reduces depressive-like behavior and proinflammatory cytokines in ovariectomized female rats  

PubMed Central

Background Soyo-san is a traditional oriental medicinal formula, a mixture of 9 crude drugs, and it has been clinically used for treating mild depressive disorders. The role of pro- and anti-inflammatory cytokines in psychiatric disorders has been the focus of great research attention in recent years. In the present study, we detected the antidepressant effect of soyo-san in the ovariectomized and repeated stressed female rats. Methods This study was designed to evaluate the antidepressant-like effect of soyo-san on the forced swimming test (FST). The rats were randomly divided into the following groups: the nonoperated and nonstressed group (non-op), the nonoperated and stressed group (non-op?+?ST), the ovariectomized and stress group (OVX) and sham operated and stressed group (sham), the ovariectomized and stressed group (OVX?+?ST), the ovariectomized, stressed and soyo-san 100 mg/kg treated group (SOY100) and the ovariectomized, stressed and soyo-san 400 mg/kg treated group (SOY400). The rats were exposed to immobilization stress (IMO) for 14day (2 h/14day), and soyo-san (100 mg/kg and 400 mg/kg) was administrated during the same time. In the same animals, the levels of corticosterone and interleukin-1-beta (IL-1?) were examined in the serum. Also, the change of IL-1? expression in brain regions was examined after behavior test. Results In the FST, the lower dose (100 mg/kg) of extract was effective in reducing immobility, along with an increase in swimming time. The serum levels of corticosterone and IL-1? in the SOY groups were significantly lower than those in the control group. In the brain, the expression of IL-1? positive neurons in the control group were significantly increased in the paraventricular nucleus (PVN) and hippocampus compared to the non-op. However, soyo-san groups significantly reduced the IL-1?-ir neurons in the PVN and hippocampal regions compared to the control. Conclusion The present results demonstrated that soyo-san effectively reduced behavioral and patho-physiological depression-like responses. Trial registration: Our results suggest that soyo-san may be useful for immune regulator in repeated stress-induced ovariectomized female rats. PMID:24444307



Effects of Mixtures of Polychlorinated Biphenyls, Methylmercury, and Organochlorine Pesticides on Hepatic DNA Methylation in Prepubertal Female Sprague-Dawley Rats  

Microsoft Academic Search

DNA methylation is one of the epigenetic mechanisms that regulates gene expression, chromosome structure, and stability. Our objective was to determine whether the DNA methylation system could be a target following in utero and postnatal exposure to human blood contaminants. Pregnant rats were dosed daily from gestation day 1 until postnatal day 21 with 2 dose levels of either organochlorine

Daniel Desaulniers; Gong-hua Xiao; Hong Lian; Yong-Lai Feng; Jiping Zhu; Jamie Nakai; Wayne J. Bowers



Abortifacient activity of Plumeria rubra (Linn) pod extract in female albino rats.  


To evaluate the potential abortifacient activity of the aqueous, alcohol, ethyl acetate and chloroform extracts of P. rubra pod in female albino rats 50, 100 and 200 mg/kg body weight doses of each extract were administered from day 11 to 15 of pregnancy and animals were allowed to go full-term. The phytochemical screening revealed the presence of alkaloids, flavonoids, simple phenolics, steroids, tannins and saponins. Clinical toxicity symptoms such as respiratory distress, salivation, weight loss, dull eyes, diarrhea, and change in the appearance of fur as well as mortality were not observed in the animals at any period of the experiment. All the four extracts of P. rubra pods exhibited abortifacient activity (8-100%). The extracts significantly reduced the number of live fetuses, whereas the resorption index and post implantation losses increased significantly. The % of abortion was found to be highest (100%) with 200 mg/kg dose of alcoholic extract of P. rubra pods. PMID:23214263

Dabhadkar, Dinesh; Zade, Varsha




PubMed Central

Ethanolic extracts of Ailanthus exceisa (AE). Toddalia asiatica (TA) and Araucaria bidwilli (AB) were screened by the anti-pyretic activity in yeast induced hyperthermic test model in the laboratory. Dose of AE (100), TA (60) and AB (30) mg., equivalent of the plant material per kg. Body weight of the extracts were administered orally to the female albino rats. Acute toxicity and preliminary phytochemical screening were conducted for all the extracts. LD 50 values on oral administration of the extracts were found to be AE (1000), AB (350) and TA (250) mg. per kg. body weight respectively. Both the root and aerial part fractions of TA displayed a pronounced anti-pyretic activity comparable to the standard drug paracetamol. AB oleoresin fraction was also found to show anti-pyretic effect. These observations however, confirm the folk-medical practices still prevailing among the tribes. PMID:22556707

Suresh, B.; Dhanasekaran, S.; Elango, K.; Sethuraman, M.; Rajan, S.



Effects of Selective Androgen Receptor Modulator (SARM) Treatment in Osteopenic Female Rats  

Microsoft Academic Search

Purpose  Although androgens are known to protect bone, side effects and poor oral bioavailability have limited their use. We previously\\u000a reported that S-3-(4-acetylamino-phenoxy)-2-hydroxy-2-methyl-N-(4-nitro-3-trifluoromethyl-phenyl)-propionamide (S-4) is a\\u000a potent and tissue-selective androgen receptor modulator (SARM). This study was designed to evaluate the skeletal effects of\\u000a S-4 in an osteopenic model.\\u000a \\u000a \\u000a \\u000a \\u000a Methods  Aged female rats were gonadectomized or sham operated on day 1 and assigned

Jeffrey D. Kearbey; Wenqing Gao; Scott J. Fisher; Di Wu; Duane D. Miller; James T. Dalton



Direct stimulatory effects of oxytocin in female rat gonadotrophs and somatotrophs in vitro: comparison with lactotrophs.  


The peptide oxytocin (OT) is secreted by hypothalamic neurons and exerts numerous actions related to reproduction. OT stimulation of prolactin secretion in female rats is important during the estrous cycle, pregnancy, and lactation. Here we report that OT also stimulates transients of intracellular Ca(2+) concentration in somatotrophs and gonadotrophs as well as the release of GH and LH in a dose-dependent manner with EC50 values that closely correspond to the ligand affinity of the OT receptor (OTR). Remarkably, the hormone-releasing effect of OT in these two cell types is 2 orders of magnitude more sensitive than that in lactotrophs. The specific OTR agonist [Thr(4),Gly(7)]-oxytocin acutely stimulated the release of LH, GH, and prolactin from female rat pituitary cells in primary culture and increased intracellular Ca(2+) concentration in gonadotrophs, somatotrophs, and lactotrophs. In these three cell types, the effects on hormone release and intracellular Ca(2+) of both OT and [Thr(4),Gly(7)]oxytocin were abolished by the specific OT receptor antagonist desGly-NH2-d(CH2)5[D-Tyr(2),Thr(4)]OVT but not by the highly selective vasopressin V1a receptor antagonist, d(CH2)5[Tyr(Me)(2),Dab(5)]AVP. Furthermore, 10 nM arginine vasopressin stimulated LH and GH release comparably with a dose of OT that was at least 10 times lower. Finally, the presence of the OTR-like immunoreactivity could be observed in all three cell types. Taken together, these results show that OT directly stimulates gonadotrophs, somatotrophs, and lactotrophs through OT receptors and suggest that OT signaling may serve to coordinate the release of different pituitary hormones during specific physiological conditions. PMID:25406939

Gonzalez-Iglesias, Arturo E; Fletcher, Patrick A; Arias-Cristancho, José A; Cristancho-Gordo, Ruth; Helena, Cleyde V; Bertram, Richard; Tabak, Joël



Adenosine A2A receptor modulation of juvenile female rat skeletal muscle microvessel permeability.  


Little is known of the regulation of skeletal muscle microvascular exchange under resting or stimulating conditions. Adenosine (ADO) levels in skeletal muscle increase during physiological (exercise) and pathological (hypoxia, inflammation, and ischemia) conditions. Later stages of these pathologies are characterized by the loss of vascular barrier integrity. This study focused on determining which ADO receptor mediates the robust reduction in microvessel permeability to rat serum albumin (P(s)(RSA)) observed in juvenile female rats. In microvessels isolated from abdominal skeletal muscle, ADO suffusion induced a concentration-dependent reduction in arteriolar [log(IC(50)) = -9.8 +/- 0.2 M] and venular [log(IC(50)) = -8.4 +/- 0.2 M] P(s)(RSA). RT-PCR and immunoblot analysis demonstrated mRNA and protein expression of ADO A(1), A(2A), A(2B), and A(3) receptors in both vessel types, and immunofluorescence assay revealed expression of the four subtype receptors in the microvascular walls (endothelium and smooth muscle). P(s)(RSA) responses of arterioles and venules to ADO were blocked by 8-(p-sulphophenyl)theophylline, a nonselective A(1) and A(2) antagonist. An A(2A) agonist, CGS21680, was more potent than the A(1) agonist, cyclopentyladenosine, or the most-selective A(2B) agonist, 5'-(N-ethylcarboxamido)adenosine. The ability of CGS21680 or ADO to reduce P(s)(RSA) was abolished by the A(2A) antagonist, ZM241385. An adenylyl cyclase inhibitor, SQ22536, blocked the permeability response to ADO. In aggregate, these results demonstrate that, in juvenile females (before the production of the reproductive hormones), ADO enhances skeletal muscle arteriole and venule barrier function predominantly via A(2A) receptors using activation of adenylyl cyclase-signaling mechanisms. PMID:16815983

Wang, Jianjie; Huxley, Virginia H



Lipid-Lowering Effects of Tetradecylthioacetic Acid in Antipsychotic-Exposed, Female Rats: Challenges with Long-Term Treatment  

PubMed Central

Background Psychiatric patients often require chronic treatment with antipsychotic drugs, and while rats are frequently used to study antipsychotic-induced metabolic adverse effects, long-term exposure has only partially mimicked the appetite-stimulating and weight-inducing effects found in the clinical setting. Antipsychotic-induced effects on serum lipids are also inconsistent in rats, but in a recent study we demonstrated that subchronic treatment with the orexigenic antipsychotic olanzapine resulted in weight-independent increase in serum triglycerides and activation of lipogenic gene expression in female rats. In addition, a recent long-term study in male rats showed that chronic treatment with antipsychotic drugs induced dyslipidemic effects, despite the lack of weight gain. Aims In the current study, we sought to examine long-term effects of antipsychotic drugs on weight gain, lipid levels and lipid composition after twice-daily administration of antipsychotics to female rats, and to investigate potential beneficial effects of the lipid-lowering agent tetradecylthioacetic acid (TTA), a modified fatty acid. Methods Female rats were exposed to orexigenic antipsychotics (olanzapine or clozapine), metabolically neutral antipsychotics (aripiprazole or ziprasidone), or TTA for 8 weeks. Separate groups received a combination of clozapine and TTA or olanzapine and TTA. The effects of TTA and the combination of olanzapine and TTA after 2 weeks were also investigated. Results The antipsychotic-induced weight gain and serum triglyceride increase observed in the subchronic setting was not present after 8 weeks of treatment with antipsychotics, while lipid-lowering effect of TTA was much more pronounced in the chronic than in the subchronic setting, with concomitant upregulation of key oxidative enzymes in the liver. Unexpectedly, TTA potentiated weight gain in rats treated with antipsychotics. Conclusion TTA is a promising candidate for prophylactic treatment of antipsychotic-induced dyslipidemic effects, but a more valid long-term rat model for antipsychotic-induced metabolic adverse effects is required. PMID:23226405

Skrede, Silje; Fernø, Johan; Bjørndal, Bodil; Brede, Wenche Rødseth; Bohov, Pavol; Berge, Rolf Kristian; Steen, Vidar Martin



Estrogen Status Alters Tissue Distribution and Metabolism of Selenium in Female Rats1,2  

PubMed Central

A reported association between estrogen and selenium status may be important in the regulation of selenium metabolism. In this study the effect of estrogen status on the metabolism of orally administered 75Se-selenite and tissue selenium status was investigated. Female Sprague Dawley rats were bilaterally ovariectomized at 7 weeks of age and implanted with either a placebo pellet (OVX) or pellet containing estradiol (OVX+E2), or were sham operated (Sham). At 12 weeks of age, 60 ?Ci of 75Se as selenite was orally administered to OVX and OVX+E2 rats. Blood and organs were collected 1, 3, 6, and 24h after dosing. Estrogen status was associated with time dependent differences in distribution of 75Se in plasma, RBC, liver, heart, kidney, spleen, brain, and thymus and incorporation of 75Se into plasma selenoprotein P (Sepp1) and glutathione peroxidase (GPx). Estrogen-treatment also significantly increased selenium concentration and GPx activity in plasma, liver, and brain, selenium concentration in RBC, and hepatic Sepp1 and GPx1 mRNA. These results suggest that estrogen status affects tissue distribution of selenium by modulating Sepp1 as this protein plays a central role in selenium transport. PMID:21684133

Zhou, Xiaodong; Smith, Anne M.; Failla, Mark L.; Hill, Kristina E.; Yu, Zhongtang



Estrogen effects on angiotensin receptors are modulated by pituitary in female rats  

SciTech Connect

The present studies were designed to test the hypothesis that changes in angiotensin II (ANG II) receptors might modulate the layered target tissue responsiveness accompanying estradiol administration. Estradiol was infused continuously in oophorectomized female rats. Aldosterone was also infused in control and experimental animals to avoid estrogen-induced changes in renin and ANG II. ANG II binding constants were determined in radioreceptor assays. Estradiol increased binding site concentration in adrenal glomerulosa by 76% and decreased binding sites of uterine myometrium and glomeruli by 45 and 24%, respectively. There was an accompanying increase in the affinity of ANG II binding to adrenal glomerulosa and uterine myometrium. Because estrogen is a potent stimulus of prolactin release from the pituitary of rodents, studies were also designed to test the hypothesis that prolactin may mediate some or all of the estrogen-induced effects observed. Hypophysectomy abolished estradiol stimulation of prolactin release and most ANG II receptor changes. Prolactin administration to pituitary intact rats was associated with a 50% increase in receptor density of adrenal glomerulosa simulating estradiol administration. However, the changes in glomeruli and uterine myometrium were opposite in that both tissues also increased receptor density, suggesting that prolactin was not the sole mediator of the estrogen-induced receptor changes. In conclusion, regulation of ANG II receptors in a number of diverse target tissues by estradiol is complex with contributions from estrogens and pituitary factors, which include but do not exclusively involve prolactin.

Douglas, J.G.



Assessment of Genotoxic Potential of Arsenic in Female Albino Rats at Permissible Dose Levels  

PubMed Central

Background: Arsenic is a wide spread environmental contaminant and has been recognized as a genotoxic element which is of major public health concern. Aim: The present study evaluates the genotoxic potential of arsenic at low permissible dose levels. Materials and Methods: Forty-eight mature female rats were divided into four groups of 12 animals each. Group I animals received distilled water and served as control. Group II-IV animals received sodium arsenite dissolved in distilled water continuously for a period of 60 days at the dose of 10, 30 and 50 ?g/L (ppb) respectively. Six rats from each group were sacrificed after 30 days of arsenic exposure and the remaining animals were sacrificed after 60 days. Liver was excised from the sacrificed animals to study the probable advent signs of carcinogenicity measured through microsomal degranulation test. Assessment of mutagenic potential of arsenic was evaluated through chromosomal aberrations observed in the bone marrow cells. Results: The levels of RNA and proteins decreased significantly (P ? 0.01) in all the three doses administered along with an increase in % microsomal degranulation in hepatic fraction when compared to control at both 30 and 60 days time period. A dose-dependent increase in chromosome aberrations like fragmentation, breakage has been observed in all the treated animals. Conclusion: The results of present study revealed that chronic exposure of arsenic even at its low permissible dose limits results in carcinogenic and mutagenic effects which emphasize its genotoxic possibility. PMID:24748731

Mehta, Madhuri; Hundal, Swarndeep Singh



Effects of the essential oil from citrus lemon in male and female rats exposed to a persistent painful stimulation  

Microsoft Academic Search

The ability of olfaction to modulate behavior in mammalian species has repeatedly been demonstrated. Here we tested the properties of the volatile components of lemon essential oil. Male and female rats were allowed to inhale the aroma while experiencing a persistent nociceptive input (50 ?l formalin, 5%); in the same animals the c-Fos immunohistochemistry was used to test the degree

Anna Maria Aloisi; Ilaria Ceccarelli; Flavio Masi; Andrea Scaramuzzino




EPA Science Inventory

IN UTERO EXPOSURE TO ATRAZINE INDUCES DELAYED PUBERTY OF LONG EVANS RATS: DAM-MEDIATED EFFECTS IN FEMALES. J L Rayner1 and S E Fenton2. 1 University of North Carolina at Chapel Hill, School of Public Health, Chapel Hill, NC, and 2 Reproductive Toxicology Divisio...



EPA Science Inventory

PERINATAL EXPOSURE TO ATRAZINE SUPPRESSES JUVENILE IMMUNE FUNCTION IN MALE, BUT NOT FEMALE SPRAGUE-DAWLEY RATS. AA Rooney1 and RW Luebke2. 1NCSU/USEPA CVM, Department of Anatomy, Physiological Sciences, and Radiology, Raleigh, NC;2USEPA, NHEERL, RTP, NC. The ability of the ...



EPA Science Inventory




EPA Science Inventory




EPA Science Inventory

Effects of Prenatal Testosterone Propionate and Vinclozolin on Perinatal and Infantile Development of Male and Female Rats Cynthia Wolf1,2, Jonathan Furr1, Gerald A. LeBlanc2, and L. Earl Gray, Jr.1 1USEPA, NHEERL, RTD, EB, RTP, NC 27711, 2Dept. of Environmental and Molecu...



EPA Science Inventory

The pesticide methoxychlor (MXC) is a proestrogen which is metabolized to a compound that has been shown to exhibit estrogenic activity in vivo and in vitro. Following long-term exposure of female rats to MXC, fertility is reduced and fetotoxicity is evident. However, the effects...



EPA Science Inventory

Goldman, JM and Murr, AS. Dibromoacetic Acid-induced Elevations of Estradiol in Both Cycling and Ovariectomized / Estradiol-implanted Female Rats ABSTRACT Haloacetic acids are one of the principal classes of disinfection by-products generated by the chlorination of mun...


Reduction of extinction and reinstatement of cocaine seeking by wheel running in female rats  

PubMed Central

Rationale and objectives Previous work has shown that wheel running reduced the maintenance of cocaine self-administration in rats. In the present study, the effect of wheel running on extinction and reinstatement of cocaine seeking was examined. Female rats were trained to run in a wheel during 6-h sessions, and they were then catheterized and placed in an operant conditioning chamber where they did not have access to the wheel but were allowed to self-administer iv cocaine. Subsequently, rats were divided into four groups and were tested on the extinction and reinstatement of cocaine seeking while they had varying access to a wheel in an adjoining compartment. The four groups were assigned to the following wheel access conditions: (1) wheel running during extinction and reinstatement (WER), (2) wheel running during extinction and a locked wheel during reinstatement (WE), (3) locked wheel during extinction and wheel running during reinstatement (WR), and (4) locked wheel during extinction and reinstatement (WL). WE and WR were retested later to examine the effect of one session of wheel access on cocaine-primed reinstatement. Results There were no group differences in wheel revolutions, in rate of acquisition of cocaine self-administration, or in responding during maintenance when there was no wheel access. However, during extinction, WE and WER responded less than WR and WL. WR and WER had lower cocaine-primed reinstatement than WE and WL. One session of wheel exposure in WE also suppressed cocaine-primed reinstatement. Conclusions Wheel running immediately and effectively reduced cocaine-seeking behavior, but concurrent access to running was necessary. Thus, exercise is a useful and self-sustaining intervention to reduce cocaine-seeking behavior. PMID:20112008

Zlebnik, Natalie E.; Anker, Justin J.; Gliddon, Luke A.



Identification of neural cells activated by mating stimulus in the periaqueductal gray in female rats  

PubMed Central

Induction of lordosis as typical female sexual behavior in rodents is dependent on a mount stimulus from males and blood levels of estrogen. Periaqueductal gray (PAG) efferent neurons have been suggested to be important for lordosis behavior; however, the neurochemical basis remains to be understood. In this study, we neuroanatomically examined (1) whether PAG neurons activated by mating stimulus project to the medullary reticular formation (MRF), which is also a required area for lordosis; and (2) whether these neurons are glutamatergic. Mating stimulus significantly increased the number of cFos-immunoreactive (ir) neurons in the PAG, particularly in its lateral region. Half of cFos-ir neurons in the lateral PAG were positive for a retrograde tracer (FluoroGold; FG) injected into the MRF. cFos-ir neurons also colocalized with mRNA of vesicular glutamate transporter 2 (vGLUT2), a molecular marker for glutamatergic neurons. Using retrograde tracing and in situ hybridization in conjunction with fluorescent microscopy, we also found FG and vGLUT2 mRNA double-positive neurons in the lateral PAG. These results suggest that glutamatergic neurons in the lateral PAG project to the MRF and are involved in lordosis behavior in female rats. PMID:25565950

Yamada, Shunji; Kawata, Mitsuhiro



Estradiol affects liver mitochondrial function in ovariectomized and tamoxifen-treated ovariectomized female rats  

SciTech Connect

Given the tremendous importance of mitochondria to basic cellular functions as well as the critical role of mitochondrial impairment in a vast number of disorders, a compelling question is whether 17{beta}-estradiol (E2) modulates mitochondrial function. To answer this question we exposed isolated liver mitochondria to E2. Three groups of rat females were used: control, ovariectomized and ovariectomized treated with tamoxifen. Tamoxifen has antiestrogenic effects in the breast tissue and is the standard endocrine treatment for women with breast cancer. However, under certain circumstances and in certain tissues, tamoxifen can also exert estrogenic agonist properties. We observed that at basal conditions, ovariectomy and tamoxifen treatment do not induce any statistical alteration in oxidative phosphorylation system and respiratory chain parameters. Furthermore, tamoxifen treatment increases the capacity of mitochondria to accumulate Ca{sup 2+} delaying the opening of the permeability transition pore. The presence of 25 {mu}M E2 impairs respiration and oxidative phosphorylation system these effects being similar in all groups of animals studied. Curiously, E2 protects against lipid peroxidation and increases the production of H{sub 2}O{sub 2} in energized mitochondria of control females. Our results indicate that E2 has in general deleterious effects that lead to mitochondrial impairment. Since mitochondrial dysfunction is a triggering event of cell degeneration and death, the use of exogenous E2 must be carefully considered.

Moreira, Paula I. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Physiology, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Custodio, Jose B.A. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Biochemistry, Faculty of Pharmacy, University of Coimbra, 3005-504 Coimbra (Portugal); Nunes, Elsa [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Physiology, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Moreno, Antonio [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Marine Research, University of Coimbra, 3005-504 Coimbra (Portugal); Seica, Raquel [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Physiology, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Oliveira, Catarina R. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal); Institute of Biochemistry, Faculty of Medicine, University of Coimbra, 3005-504 Coimbra (Portugal); Santos, Maria S. [Center for Neuroscience and Cell Biology, University of Coimbra, 3005-504 Coimbra (Portugal) and Department of Zoology, Faculty of Sciences and Technology, University of Coimbra, 3005-504 Coimbra (Portugal)]. E-mail:



Female spontaneously hypertensive rats have a compensatory increase in renal regulatory T cells in response to elevations in blood pressure.  


Female spontaneously hypertensive rats (SHR) have more regulatory T cells (Tregs) in their kidneys than males. The goal of this study was to determine the impact of blood pressure (BP) on the renal immune profile. We hypothesize that increases in BP promote a proinflammatory renal T cell and cytokine profile in SHR, although females will have greater hormone-dependent increases in Tregs and males will have greater increases in Th17 cells. Renal T cell and cytokine profiles were assessed in male and female Wistar-Kyoto rats and male and female SHR treated with vehicle or hydrochlorothiazide and reserpine (HCTZ) from 6 to 12 (6-HCTZ) or 11 to 13 weeks of age (2-HCTZ). Regardless of sex, SHR had a more proinflammatory renal immune profile than Wistar-Kyoto rats. 6-HCTZ attenuated age-related increases in BP and 2-HCTZ reversed hypertension compared with vehicle-treated SHR. Neither 6-HCTZ nor 2-HCTZ altered CD3(+), CD4(+), or CD8(+) T cells in either sex. Both treatments decreased Tregs only in female SHR abolishing sex differences in Tregs. 6-HCTZ has no impact on Th17 cells in either sex and 2-HCTZ had a minimal impact on renal Th17 cells. To further assess mechanisms mediating sex differences in the renal immune profile, male and female SHR were gonadectomized to determine the impact of sex hormones. Gonadectomy increased proinflammatory markers in both sexes, suggesting that both male and female sex hormones are anti-inflammatory. In conclusion, BP contributes to sex differences in the renal T-cell profile of SHR; female SHR increase renal Tregs in response to increases in BP. PMID:24914200

Tipton, Ashlee J; Baban, Babak; Sullivan, Jennifer C



Single acute stress-induced progesterone and ovariectomy alter cardiomyocyte contractile function in female rats  

PubMed Central

Aim To assess how ovarian-derived sex hormones (in particular progesterone) modify the effects of single acute stress on the mechanical and biochemical properties of left ventricular cardiomyocytes in the rat. Methods Non-ovariectomized (control, n?=?8) and ovariectomized (OVX, n?=?8) female rats were kept under normal conditions or were exposed to stress (control-S, n?=?8 and OVX-S, n?=?8). Serum progesterone levels were measured using a chemiluminescent immunoassay. Left ventricular myocardial samples were used for isometric force measurements and protein analysis. Ca2+-dependent active force (Factive), Ca2+-independent passive force (Fpassive), and Ca2+-sensitivity of force production were determined in single, mechanically isolated, permeabilized cardiomyocytes. Stress- and ovariectomy-induced alterations in myofilament proteins (myosin-binding protein C [MyBP-C], troponin I [TnI], and titin) were analyzed by sodium dodecyl sulfate gel electrophoresis using protein and phosphoprotein stainings. Results Serum progesterone levels were significantly increased in stressed rats (control-S, 35.6?±?4.8 ng/mL and OVX-S, 21.9?±?4.0 ng/mL) compared to control (10?±?2.9 ng/mL) and OVX (2.8?±?0.5 ng/mL) groups. Factive was higher in the OVX groups (OVX, 25.9?±?3.4 kN/m2 and OVX-S, 26.3?±?3.0 kN/m2) than in control groups (control, 16.4?±?1.2 kN/m2 and control-S, 14.4?±?0.9 kN/m2). Regarding the potential molecular mechanisms, Factive correlated with MyBP-C phosphorylation, while myofilament Ca2+-sensitivity inversely correlated with serum progesterone levels when the mean values were plotted for all animal groups. Fpassive was unaffected by any treatment. Conclusion Stress increases ovary-independent synthesis and release of progesterone, which may regulate Ca2+-sensitivity of force production in left ventricular cardiomyocytes. Stress and female hormones differently alter Ca2+-dependent cardiomyocyte contractile force production, which may have pathophysiological importance during stress conditions affecting postmenopausal women. PMID:24891282

Kalász, Judit; Tóth, Enik? Pásztor; Bódi, Beáta; Fagyas, Miklós; Tóth, Attila; Pal, Bhattoa Harjit; Vári, Sándor G.; Balog, Marta; Blažeti?, Senka; Heffer, Marija; Papp, Zoltán; Borbély, Attila



Effect of the aqueous extract of Foeniculum vulgare (fennel) on the kidney in experimental PCOS female rats  

PubMed Central

Objective: Foeniculum vulgare seed (F. vulgare) is an herbal plant which is used with phytoestrogene compounds for polycystic ovary syndrome (PCOS) treatment. In this research, renoprotective effect of the aqueous extract of Foeniculum vulgare (AEF) in experimental PCOS female rats is studied. Materials and Methods: Forty female rats were randomly divided into five groups. The first group served as control, was injected with an equivalent volume (0.2 ml) of normal saline, and received normal diet. Animals in the second group were non poly cystic ovary syndrome (PCOS) rats which were treated with intragastric administration of aqueous extract of F. vulgare (150 mg/kg b.w.). In the third group, the rats were treated with intraperitoneal injection of estradiolvalerate (EV) (4 mg in 0.2 ml of sesame oil). The fourth groups were treated with EV and AEF (150mg/kg bw) with the same route. The fifth groups were treated with EV and AEF (100mg/kg bw). After 4 weeks of study, all of the rats were sacrificed, their kidneys tissues were processed for light microscopy, and some biochemical parameters of serum were measured. Results: The mean values of blood urea nitrogen in PCOS rats treated with low dose of AEF and EV and non-treated, was significantly (p<0.05) increased compared with non-PCOS and PCOS rats treated with high dose of AEF. Moreover, histopathological changes of kidney samples were comparable in PCOS rats with respect to treated groups with AEF. Conclusion: Aqueous extract of fennel seed showed the beneficial effect (especially at dose of 150 mg/kg b.w.) on renal function in PCOS rats. PMID:25050308

Sadrefozalayi, Somayyeh; Farokhi, Farah



Chronic alcohol consumption disrupts myocardial protein balance and function in aged, but not adult, female F344 rats  

PubMed Central

The purpose of this study was to assess whether the deleterious effect of chronic alcohol consumption differs in adult and aged female rats. To address this aim, adult (4 mo) and aged (18 mo) F344 rats were fed a nutritionally complete liquid diet containing alcohol (36% total calories) or an isocaloric isonitrogenous control diet for 20 wk. Cardiac structure and function, assessed by echocardiography, as well as myocardial protein synthesis and proteolysis did not differ in either alcohol- versus control-fed adult rats or in adult versus aged control-fed rats. In contrast, cardiac function was impaired in alcohol-fed aged rats compared with age-matched control rats. Additionally, alcohol feeding decreased cardiac protein synthesis that was associated with decreased phosphorylation of 4E-BP1 and S6K1. This reduction in mammalian target of rapamycin (mTOR) kinase activity was associated with reduced eIF3f and binding of both Raptor and eIF4G to eIF3. Proteasome activity was increased in alcohol-fed aged rats with a coordinate elevation in the E3 ligases atrogin-1 and muscle RING-finger protein-1 (MuRF1). These changes were associated with increased regulated in development and DNA damage response 1 (REDD1) and phosphorylation of AMP-activated protein kinase (AMPK) but no increase in AKT or forkhead transcription factor (FOXO)3 phosphorylation. Finally, markers of autophagy (e.g., LC3B, Atg7, Atg12) and TNF-? were increased to a greater extent in alcohol-fed aged rats. These data demonstrate that aged female rats exhibit an enhanced sensitivity to alcohol compared with adult animals. Our data are consistent with a model whereby alcohol increases proteolysis via FOXO-independent increase in atrogin-1, which degrades eIF3f and therefore impairs formation of a functional preinitiation complex and protein synthesis. PMID:24226028

Korzick, Donna H.



Lack of efficacy of blueberry in nutritional prevention of azoxymethane-initiated cancers of rat small intenstions and colon  

Technology Transfer Automated Retrieval System (TEKTRAN)

We examined the efficacy of freeze-dried blueberry (BB) in inhibition of formation of azoxymethane (AOM)-induced colon aberrant crypt foci (ACF) and intestine tumors in male and female Sprague-Dawley rats. Pregnant rats were fed a control diet with or without 10% BB; progeny were weaned to the same...


Inhibitory and multisynaptic spines, and hemispherical synaptic specialization in the posterodorsal medial amygdala of male and female rats.  


The density of dendritic spines is sexually dimorphic and variable throughout the female estrous cycle in the rat posterodorsal medial amygdala (MePD), a relevant area for the modulation of reproductive behavior in rats. The local synaptic activity differs between hemispheres in prepubertal animals. Here we used serial section transmission electron microscopy to produce 3D reconstructions of dendritic shafts and spines to characterize synaptic contacts on MePD neurons of both hemispheres in adult males and in females along the estrous cycle. Pleomorphic spines and nonsynaptic filopodia occur in the MePD. On average, 8.6% of dendritic spines received inputs from symmetric gamma-aminobutyric acid (GABA)-immunoreactive terminals, whereas 3.6% received two synaptic contacts on the spine head, neck, or base. Presynaptic terminals in female right MePD had a higher density of synaptic vesicles and docked vesicles than the left MePD, suggesting a higher rate of synaptic vesicle release in the right MePD of female rats. In contrast, males did not show laterality in any of those parameters. The proportion of putative inhibitory synapses on dendritic shafts in the right MePD of females in proestrus was higher than in the left MePD, and higher than in the right MePD in males, or in females in diestrus or estrus. This work shows synaptic laterality depending on sex and estrous cycle phase in mature MePD neurons. Most likely, sexual hormone effects are lateralized in this brain region, leading to higher synaptic activity in the right than in the left hemisphere of females, mediating timely neuroendocrine and social/reproductive behavior. PMID:24318545

Brusco, Janaina; Merlo, Suélen; Ikeda, Érika T; Petralia, Ronald S; Kachar, Bechara; Rasia-Filho, Alberto A; Moreira, Jorge E



Access to a Running Wheel Decreases Cocaine-Primed and Cue-Induced Reinstatement in Male and Female Rats  

PubMed Central

Background Relapse to drug use after a period of abstinence is a persistent problem in the treatment of cocaine dependence. Physical activity decreases cocaine self-administration in laboratory animals and is associated with a positive prognosis in human substance-abusing populations. The purpose of this study was to examine the effects of long-term access to a running wheel on drug-primed and cue-induced reinstatement of cocaine-seeking behavior in male and female rats. Methods Long-Evans rats were obtained at weaning and assigned to sedentary (no wheel) and exercising (access to wheel) groups for the duration of the study. After 6 weeks, rats were implanted with intravenous catheters and trained to self-administer cocaine for 14 days. After training, saline was substituted for cocaine and responding was allowed to extinguish, after which cocaine-primed reinstatement was examined in both groups. Following this test, cocaine self-administration was re-established in both groups for a 5-day period. Next, a second period of abstinence occurred in which both cocaine and the cocaine-associated cues were withheld. After 5 days of abstinence, cue-induced reinstatement was examined in both groups. Results Sedentary and exercising rats exhibited similar levels of cocaine self-administration, but exercising rats responded less than sedentary rats during extinction. In tests of cocaine-primed and cue-induced reinstatement, exercising rats responded less than sedentary rats, and this effect was apparent in both males and females. Conclusions These data indicate that long-term access to a running wheel decreases drug-primed and cue-induced reinstatement, and that physical activity may be effective at preventing relapse in substance-abusing populations. PMID:21885215

Smith, Mark A.; Pennock, Michael M.; Walker, Katherine L.; Lang, Kimberly C.



Improving Active and Passive Avoidance Memories Deficits Due to Permanent Cerebral Ischemia by Pomegranate Seed Extract in Female Rats  

PubMed Central

Background: This study aimed to evaluate the effect of two weeks oral administration of pomegranate seed extract (PGSE) on active and passive avoidance memories after permanent bilateral common carotid arteries occlusion (2CCAO) to induce permanent cerebral ischemia in adult female rats. Methods: Seventy adult female Wistar rats (250 ± 20 g) were used. Animals were divided randomly into seven groups with 10 in each: 1) Sham-operated; 2) Ischemic; 3–6) Ischemic received PGSE (100, 200, 400, and 800 mg/2mL/kg, orally) for 14 days; 7) Ischemic received vehicle. In order to create 2CCAO, carotid arteries were ligatured and then cut bilaterally. Active and passive avoidance task were measured using criterion condition responses (CCRs) in Y-maze and step-through latency (STL) in two-way shuttle box in all female rats. Results: Both active and passive avoidance memories were significantly impaired in rats after cerebral hypoxia-ischemia (CHI) (P < 0.001). PGSE treatment significantly improved passive and active memory impairments with 2CCAO (P < 0.05, P < 0.01, and P < 0.001). No toxicity was observed even with high-dose PGSE consumption (800 mg/kg, for 14 days). Conclusion: PGSE exhibits therapeutic potential for avoidance memories, which is most likely related at least in part to its antioxidative and free radical scavenging actions. PMID:23983574

Sarkaki, Alireza; Rezaiei, Moslem; Gharib naseri, MohammadKazem; Rafieirad, Maryam



The Preventive Effects of Diminazene Aceturate in Renal Ischemia/Reperfusion Injury in Male and Female Rats  

PubMed Central

Background. Angiotensin-converting enzyme 2/angiotensin (1-7)/Mas receptor (ACE2/Ang-1-7/MasR) appears to counteract most of the deleterious actions of angiotensin-converting enzyme/angiotensin II/angiotensin II receptor 1 (ACE/Ang II/AT1R) in renal ischemia/reperfusion (I/R) injury but ACE2 activity and its levels are sexually dimorphic in the kidney. This study was designed to evaluate the effects of activation endogenous ACE2 using the diminazene aceturate (DIZE) in renal I/R injury in male and female rats. Methods. 36 Wistar rats were divided into two groups of male and female and each group distinct to three subgroups (n = 6). I/R group was subjected to 45?min of bilateral ischemia and 24?h of reperfusion, while treatment group received DIZE (15?mg/kg/day) for three days before the induction of I/R. The other group was assigned as the sham-operated group. Results. DIZE treatment in male rats caused a significant decrease in blood urea nitrogen (BUN), creatinine, liver functional indices, serum malondialdehyde (MDA), and increase kidney nitrite levels (P < 0.05), and in female rats a significant increase in creatinine and decrease serum nitrite levels compared to the I/R group (P < 0.05). Conclusions. DIZE may protect the male kidney from renal I/RI through antioxidant activity and elevation of circulating nitrite level. PMID:25478235



Effects of unilateral ovariectomy before and after mating on growth of corpora lutea and peripheral progestagen concentrations in pregnant rats.  


Unilateral ovariectomy was performed on 20 rats 4-5 wk before mating (ULO-B group), and 18 rats 8 days after mating (ULO-A group); 16 rats were maintained as controls. The effects on growth of individual corpora lutea (CL) in the remaining ovary and peripheral blood progestagen concentrations were examined. CL hypertrophy was observed by Day 13 in the ULO-B group and by Day 16 in the ULO-A group. Progesterone and 20 alpha-dihydroprogesterone concentrations were double control values at Day 16 in the ULO-B group, but half the control values in the ULO-A group. The CL hypertrophy and increased progestagen concentrations in the ULO-B group occurred despite crowding due to a doubling of the normal number of CL within the remaining ovary. PMID:3676385

Rahima, A; Bruce, N W



Effects of energy status and diet on Bdnf expression in the ventromedial hypothalamus of male and female rats.  


Sex differences exist in the regulation of energy homeostasis in response to calorie scarcity or excess. Brain-derived neurotrophic factor (BDNF) is one of the anorexigenic neuropeptides regulating energy homeostasis. Expression of Bdnf mRNA in the ventromedial nucleus of the hypothalamus (VMH) is closely associated with energy and reproductive status. We hypothesized that Bdnf expression in the VMH was differentially regulated by altered energy balance in male and female rats. Using dietary intervention, including fasting-induced negative energy status and high-fat diet (HFD) feeding-induced positive energy status, along with low-fat diet (LFD) feeding and HFD pair-feeding (HFD-PF), effects of diets and changes in energy status on VMH Bdnf expression were compared between male and female rats. Fasted males but not females had lower VMH Bdnf expression than their fed counterparts following 24-hour fasting, suggesting that fasted males reduced Bdnf expression to drive hyperphagia and body weight gain. Male HFD obese and HFD-PF non-obese rats had similarly reduced expression of Bdnf compared with LFD males, indicating that dampened Bdnf expression was associated with feeding a diet high in fat instead of increased adiposity. Decreased BDNF signaling during HFD feeding would increase a drive to eat and may contribute to diet-induced obesity in males. In contrast, VMH Bdnf expression was stably maintained in females when energy homeostasis was disturbed. These results suggest sex-distinct regulation of central Bdnf expression by diet and energy status. PMID:24709620

Liu, Xian; Zhu, Zheng; Kalyani, Manu; Janik, James M; Shi, Haifei



Pre-pubertal gonadectomy and the social consequences of acute ethanol in adolescent male and female rats.  


It has previously been shown that pre-pubertal or adult gonadectomy (GX) increases ethanol intake in male rats. This study examined whether this sex-selective increase reflects a GX-induced maintenance in males of more adolescent-typical responsiveness to ethanol characterized by enhanced sensitivity to positive (e.g., socially facilitating) and a decreased sensitivity to adverse (e.g., socially inhibitory) effects of ethanol. Male and female Sprague-Dawley rats were pre-pubertally GX, sham (SH)-operated, or non-manipulated (NM) at postnatal day (P) 25. During the late adolescent transition into adulthood (P48 - baseline day), rats were given a saline injection, placed alone into a familiar test apparatus for 30min and then exposed for 10min to an unfamiliar partner of the same age and sex. On the following day (P49), similar testing occurred after administration of 0.5, 0.75, 1.0 or 1.25g/kg ethanol. At baseline, GX males and females displayed higher levels of social activity (especially adolescent-typical play and contact behavior) than SH and NM animals, with GX females displaying greater social activity than GX males. Neither males nor females demonstrated social facilitation at lower ethanol doses, regardless of hormonal status. Whereas the social inhibitory effects of higher doses of ethanol were similar across groups among females, SH males were less sensitive than both GX and NM males to ethanol-induced social inhibition. These results suggest that enhanced ethanol intake in GX males is not related to alterations in sensitivity to ethanol's social inhibitory effects. GX, however, results in retention of adolescent-typical social behaviors, with older GX adolescent rats resembling early adolescents in exhibiting elevated social activity-particularly play and contact behavior. PMID:24816080

Morales, Melissa; Varlinskaya, Elena I; Spear, Linda P



Myocardial contractility is preserved early but reduced late after ovariectomy in young female rats  

PubMed Central

Background Ovarian sex hormones (OSHs) are implicated in cardiovascular function. It has been shown that OSHs play an important role in the long term regulation of cardiac sarcoplasmic reticulum (SR) function and contractility, although early effects of OSHs deprivation on myocardial contractility have not yet been determined. This study evaluated the early and late effects of OSHs deficiency on left ventricular contractility in rats after ovariectomy. Methods Young female Wistar rats were divided into 3 groups (n = 9-15): sham operated (Sham), ovariectomized (Ovx) and Ovx treated with estradiol (1 mg/kg, i.m., once a week) (Ovx+E2). After 7, 15, 30 and 60 days post Ovx, left ventricle papillary muscle was mounted for isometric tension recordings. The inotropic response to Ca2+ (0.62 to 3.75 mM) and isoproterenol (Iso 10-8 to 10-2 M) and contractility changes in response to rate changes (0.25 to 3 Hz) were assessed. Protein expression of SR Ca2+-ATPase (SERCA2a) and phospholamban (PLB) in the heart was also examined. Results The positive inotropic response to Ca2+ and Iso at 7, 15, and 30 days after Ovx was preserved. However, at 60 days, the Ovx group had decreased myocardial contractility which was subsequently restored with E2 replacement. The reduction in SERCA2a and increase in PLB expression observed at 60 days after Ovx were restored with E2 replacement. Conclusion This study demonstrated that myocardial contractility and expression of key Ca2+ handling proteins were preserved in the early phase and reduced at long-term during OSHs deprivation. PMID:21513549



Induction of liver monooxygenases by annatto and bixin in female rats.  


Annatto or urucum is an orange-yellow dye obtained from Bixa orellana seeds. It has been used as a natural dye in a variety of food products, drugs and cosmetics, and also in Brazilian cuisine as a condiment ('colorau'). Bixin, a carotenoid devoid of provitamin A activity, is the main pigment found in annatto. Some carotenoids (canthaxanthin, astaxanthin and beta-Apo-8'-carotenal) are known to be potent inducers of CYP1A1, a property not shared by others (beta-carotene, lycopene and lutein). Little is known, however, about the CYP1A1-inducing properties of bixin and annatto. The present study was performed to determine the effects of an annatto extract (28% bixin) and bixin (95% pure) on rat liver monooxygenases. Adult female Wistar rats were treated by gavage with daily doses of annatto (250 mg/kg body weight, which contains approximately 70 mg bixin/kg body weight), bixin (250 mg/kg body weight) or the vehicle only (corn oil, 3.75 g/kg body weight) for 5 consecutive days, or were not treated (untreated control). The activities of aniline-4-hydroxylase (A4H), ethoxycoumarin-O-deethylase (ECOD), ethoxy- (EROD), methoxy- (MROD), pentoxy- (PROD) and benzyloxy- (BROD) resorufin-O-dealkylases were measured in liver microsomes. Annatto (250 mg/kg containing 70 mg bixin/kg) induced EROD (3.8x), MROD (4.2x), BROD (3.3x) and PROD (2.4x). Bixin (250 mg/kg) was a weaker inducer of EROD (2.7x), MROD (2.3x) and BROD (1.9x) and did not alter PROD, A4H or ECOD activities. These results suggest that constituents of the extract other than bixin play an important role in the induction of CYP1A and CYP2B observed with annatto food colorings. PMID:12532234

De-Oliveira, A C A X; Silva, I B; Manhaes-Rocha, D A; Paumgartten, F J R



The impact of neonatal bisphenol-A exposure on sexually dimorphic hypothalamic nuclei in the female rat  

PubMed Central

Now under intense scrutiny, due to its endocrine disrupting properties, the potential threat the plastics component bisphenol-a (BPA) poses to human health remains unclear. Found in a multitude of polycarbonate plastics, food and beverage containers, and medical equipment, BPA is thought to bind to estrogen receptors (ERs), thereby interfering with estrogen-dependent processes. Our lab has previously shown that exposure to BPA (50mg/kg bw or 50?g/kg bw) during the neonatal critical period is associated with advancement of puberty, early reproductive senescence and ovarian malformations in female Long-Evans rats. Here, using neural tissue obtained from the same animals, we explored the impact of neonatal BPA exposure on the development of sexually dimorphic hypothalamic regions critical for female reproductive physiology and behavior. Endpoints included quantification of oxytocin-immunoreactive neurons (OT-ir) in the paraventricular nucleus (PVN), serotonin (5-HT-ir) fiber density in the ventrolateral subdivision of the ventromedial nucleus (VMNvl) as well as ER?-ir neuron number in the medial preoptic area (MPOA), the VMNvl, and the arcuate nucleus (ARC). Both doses of BPA increased the number of OT-ir neurons within the PVN, but no significant effects were seen on 5-HT-ir fiber density or ER?-ir neuron number in any of the areas analyzed. In addition to hypothalamic development, we also assessed female sex behavior and body weight. No effect of BPA on sexual receptivity or proceptive behavior in females was observed. Females treated with BPA, however, weighed significantly more than control females by postnatal day 99. This effect of BPA on weight is critical because alterations in metabolism, are frequently associated with reproductive dysfunction. Collectively, the results of this and our prior study indicate that the impact of neonatal BPA exposure within the female rat hypothalamus is region specific and support the hypothesis that developmental BPA exposure may adversely affect reproductive development in females. PMID:20696184

Adewale, Heather B.; Todd, Karina L.; Mickens, Jillian A.; Patisaul, Heather B.



Estrous cycle affects the neurochemical and neurobehavioral profile of carvacrol-treated female rats.  


Carvacrol is the major constituent of essential oils from aromatic plants. It showed antimicrobial, anticancer and antioxidant properties. Although it was approved for food use and included in the chemical flavorings list, no indication on its safety has been estimated. Since the use of plant extracts is relatively high among women, aim of this study was to evaluate carvacrol effects on female physiology and endocrine profiles by using female rats in proestrus and diestrus phases. Serotonin and metabolite tissue content in prefrontal cortex and nucleus accumbens, after carvacrol administration (0.15 and 0.45g/kg p.o.), was measured. Drug effects in behavioral tests for alterations in motor activity, depression, anxiety-related behaviors and endocrine alterations were also investigated. While in proestrus carvacrol reduced serotonin and metabolite levels in both brain areas, no effects were observed in diestrus phase. Only in proestrus phase, carvacrol induced a depressive-like behavior in forced swimming test, without accompanying changes in ambulation. The improvement of performance in FST after subchronic treatment with fluoxetine (20mg/kg) suggested a specific involvement of serotonergic system. No differences were found across the groups with regard to self-grooming behavior. Moreover, in proestrus phase, carvacrol reduced only estradiol levels without binding hypothalamic estradiol receptors. Our study showed an estrous-stage specific effect of carvacrol on depressive behaviors and endocrine parameters, involving serotonergic system. Given the wide carvacrol use not only as feed additive, but also as cosmetic essence and herbal remedy, our results suggest that an accurate investigation on the effects of its chronic exposure is warranted. PMID:21723308

Trabace, L; Zotti, M; Morgese, M G; Tucci, P; Colaianna, M; Schiavone, S; Avato, P; Cuomo, V



Effects of cadmium, calcium, age and parity on bone mineral, density and strength in female rats  

SciTech Connect

Weanling female rats were fed diets containing one of three levels of Ca (0.3, 0.6, or 0.9%) and one of four levels of Cd (0, 1, 5, or 10 ppm) in the drinking water. One half of each group was fed first as adolescents (55 days) and the other half as mature (110 days) females. Approximately 10 animals from each group were sacrificed after the first pregnancy and the remaining animals after the fourth pregnancy. Reproductive performance, plasma and bone Ca and P and bone density and strength were measured. After the first pregnancy, offspring of dams treated with 5 or 10 ppm Cd were smaller at birth than offspring of dams treated with 0 or 1 ppm Cd. After the fourth pregnancy, the decreased birth weight was evident only in offspring of dams treated with 10 ppm Cd. Offspring of dams fed 5 or 10 ppm Cd or the 0.3% Ca diet had decreased weaning weight regardless of parity. A 0.3% Ca diet superimposed upon a 5 or 10 ppm Cd intake decreased weaning weight of the male offspring after the first, but not the fourth, pregnancy with the offspring of adolescent dams affected more than those of mature dams. Offspring of dams fed the 0.9% Ca diet did not differ in weaning weight from the offspring of dams fed the 0.6% Ca diet. The 0.3% Ca diet depressed the plasma Ca and the 0.9% Ca diet elevated the plasma Ca and depressed the plasma P when compared to the 0.6% diet.

Hammond, B.F.



The herbal formula HT042 induces longitudinal bone growth in adolescent female rats.  


The effect of HT042, a blend of three herbal extracts, on longitudinal bone growth was investigated in short- and long-term rat models. In the short-term model, we divided female Sprague-Dawley rats (3 weeks old) into six groups, according to treatment: vehicle, HT042 (100 mg/kg), Phlomis umbrosa (100 mg/kg), Astragalus membranaceus (100 mg/kg), and Eleutherococcus senticosus (100 mg/kg) were administered twice daily, and recombinant human growth hormone (rhGH) (1 IU) was subcutaneously injected once daily. Treatments were maintained for 4 days in each case. On day 3, tetracycline (20 mg/kg) was injected intraperitoneally (20 mg/kg) to form the fluorescent band on the growth plates. On days 2-4, 5-bromo-2'-deoxyuridine (BrdU) (50 mg/kg) was injected intraperitoneally to label proliferating cells. On day 5, the tibias were dissected and fixed in 30% sucrose. Dehydrated bone was sectioned at a thickness of 40 ?m and observed. The bone growth in groups administered HT042 and rhGH was significantly increased to 433.50 ± 21.61 and 434.49 ± 15.21 ?m/day, respectively, from 410.03 ± 17.4 ?m/day (control). The height of the growth plates in the HT042 and rhGH groups was also significantly increased to 556.5 ± 21.1 and 544.2 ± 21.1 ?m (P rat model, the body weight, nose-tail length, and nose-anus length were measured by microknemometry for 4 weeks. The body weight of the rhGH group was significantly increased. The nose-anus length of the HT042 and rhGH groups was significantly greater at 18.5 ± 0.3 and 18.7 ± 0.3 cm compared to 18.2 ± 0.2 cm (control). PMID:21091251

Kim, Mi-Yeon; Park, Youngmi; Pandit, Naba Raj; Kim, Jiyoung; Song, Mikyung; Park, Juyeon; Choi, Ho-Young; Kim, Hocheol



Influence of ovarian and non-ovarian estrogens on weight gain in response to disruption of sweet taste – calorie relations in female rats  

PubMed Central

Regulation of energy balance in female rats is known to differ along a number of dimensions compared to male rats. Previous work from our lab has demonstrated that in female rats fed dietary supplements containing high-intensity sweeteners that may disrupt a predictive relation between sweet tastes and calories, excess weight gain is demonstrated only when females are also fed a diet high in fat and sugar, and is evidenced primarily in animals already prone to gain excess weight. In contrast, male rats show excess weight gain when fed saccharin-sweetened yogurt supplements when fed both standard chow diets and diets high in fat and sugar, and regardless of their proneness to excess weight gain. The goal of the present experiments was to determine whether ovarian, or other sources of estrogens, contributes to the resistance to excess weight gain in female rats fed standard chow diets along with dietary supplements sweetened with yogurt. Results of the first experiment indicated that when the ovaries were removed surgically in adult female rats, patterns of weight gain were similar in animals fed saccharin-sweetened compared to glucose-sweetened yogurt supplements. In the second experiment, when the ovaries were surgically removed in adult female rats, and local production of estrogens was suppressed with the aromatase inhibitor anastrozole, females fed the saccharin-sweetened yogurt consumed more energy and gained more weight than females fed the glucose-sweetened yogurt. However, when the ovaries were surgically removed prior to the onset of puberty (at 24 – 25 days of age), females given saccharin-sweetened yogurt along with vehicle gained excess weight. In contrast, weight gain was similar in those given saccharin-sweetened and glucose-sweetened yogurt along with anastrozole. The results suggest that behavioral differences between males and females in response to disruption of sweet?calorie relations may result from differences in patterns of local estrogen production. These differences may be established developmentally during the pubertal period in females. PMID:23146838

Swithers, Susan E.; Sample, Camille H.; Katz, David P.



Myelination of the corpus callosum in male and female rats following complex environment housing during adulthood  

PubMed Central

Myelination is an important process in brain development, and delays or abnormalities in this process have been associated with a number of conditions including autism, developmental delay, attention deficit disorder, and schizophrenia. Myelination can be sensitive to developmental experience; however, although the adult brain remains highly plastic, it is unknown whether myelination continues to be sensitive to experience during adulthood. Male and female rats were socially housed until four months of age, at which time they were moved into either a complex or “enriched” environment (EC) or an isolated condition (IC). Although the area of the splenium (posterior 20% of the callosum, which contains axons from visual cortical neurons) increased by about 10% following two months of EC housing, the area occupied by myelinated axons was not influenced by adult housing condition. Instead, it was the area occupied by glial cell processes and unmyelinated axons which significantly increased following EC housing. Neither the size nor the myelin content of the genu (anterior 15% of the callosum) was sensitive to manipulations of adult housing condition, but males had more area occupied by myelinated axons in both callosal regions. Finally, the inability of two months of complex environment housing during adulthood to impact the number of myelinated axons in the splenium was confirmed in a subset of animals using quantitative electron microscopy. We conclude that the sensitivity of myelination to experience is reduced in adulthood relative to development in both sexes. PMID:19596280

Markham, Julie A.; Herting, Megan M.; Luszpak, Agatha E.; Juraska, Janice M.; Greenough, William T.



The effects of rhodium on the renal function of female Wistar rats.  


In recent years, the increased use of rhodium (Rh) as an active catalyst material in modern three-way automobile catalytic converters has led to a parallel rise in environmental levels of this metal. In spite of this, the literature contains few studies of the effects of Rh on human health. The aim of this study is to assess the effects of Rh on the renal function of female Wistar rats. Our findings show that sub-acute exposure to six increasing concentrations, ranging from 0.001 to 1 mg L(-1), of Rh (III) chloride hydrate in drinking water does not induce alterations in urinary albumin levels, while, at concentrations from 0.1 to 1 mg L(-1), a significant rise in urinary levels of Retinol Binding Protein is evident and an increasing trend in urinary ?2-microglobulin, which becomes significant at 1 mg L(-1), is observed. These results therefore demonstrate a nephrotoxic action of Rh at tubular level in a wide range of doses. Interestingly, because of the recent increase in environmental Rh levels, these findings may have relevant implications both for occupationally exposed subjects and for the general population, especially children. PMID:24321336

Iavicoli, Ivo; Leso, Veruscka; Fontana, Luca; Marinaccio, Alessandro; Bergamaschi, Antonio; Calabrese, Edward J



5-HT receptor blockade in the posterior amygdala elicits feeding in female rats.  


Previous work suggests that feeding following intraventricular (i.v.t.) injections of the serotonin (5-HT)(1/2/7) antagonist metergoline (MET) is not localized to the hypothalamus. Since lesions of the posterior basolateral amygdala (pBLA) block feeding following systemic 5-HT1A agonist 8-hydroxy-2(di-n-propylamino)tetralin, the ability of intra-pBLA MET to elicit feeding was investigated. In two separate experiments, feeding of female rats was measured over 2 h following 0, 3, 10 and 30 nmol and 0, 0.03, 0.3 and 3 nmol MET (mol. wt. 403.5) injected bilaterally into each pBLA. All three doses used in Experiment 1 increased feeding over 2 h. In Experiment 2, feeding over the first hour was enhanced after the two highest doses. Since intra-pBLA MET elicits feeding comparable to that seen using much higher doses administered i.v.t. these data implicate the pBLA as an extra-hypothalamic site mediating the effects of 5-HT in feeding control. PMID:11303758

Parker, G C; Balboul, R; Hobday, J A; Coscina, D V



Distribution and posttranslational modification of synaptic ER? in the adult female rat hippocampus.  


Acute 17?-estradiol (E2) signaling in the brain is mediated by extranuclear estrogen receptors. Here we used biochemical methods to investigate the distribution, posttranslational modification, and E2 regulation of estrogen receptor-? (ER?) in synaptosomal fractions isolated by differential centrifugation from the adult female rat hippocampus. We find that ER? is concentrated presynaptically and is highly enriched with synaptic vesicles. Immunoisolation of vesicles using vesicle subtype-specific markers showed that ER? is associated with both glutamate and ?-aminobutyric acid-containing neurotransmitter vesicles as well as with some large dense core vesicles. Experiments using broad spectrum and residue-specific phosphatases indicated that a portion of ER? in synaptosomal fractions is phosphorylated at serine/threonine residues leading to a mobility shift in SDS-PAGE and creating a double band on Western blots. The phosphorylated form of ER? runs in the upper of the two bands and is particularly concentrated with synaptic vesicles. Finally, we used E2 with or without the acyl protein thioesterase 1 inhibitor, Palmostatin B, to show that 20 min of E2 treatment of hippocampal slices depletes ER? from the synaptosomal membrane by depalmitoylation. We found no evidence that E2 regulates phosphorylation of synaptosomal ER? on this time scale. These studies begin to fill the gap between detailed molecular characterization of extranuclear ER? in previous in vitro studies and acute E2 modulation of hippocampal synapses in the adult brain. PMID:23183182

Tabatadze, Nino; Smejkalova, Tereza; Woolley, Catherine S



Distribution and Posttranslational Modification of Synaptic ER? in the Adult Female Rat Hippocampus  

PubMed Central

Acute 17?-estradiol (E2) signaling in the brain is mediated by extranuclear estrogen receptors. Here we used biochemical methods to investigate the distribution, posttranslational modification, and E2 regulation of estrogen receptor-? (ER?) in synaptosomal fractions isolated by differential centrifugation from the adult female rat hippocampus. We find that ER? is concentrated presynaptically and is highly enriched with synaptic vesicles. Immunoisolation of vesicles using vesicle subtype-specific markers showed that ER? is associated with both glutamate and ?-aminobutyric acid-containing neurotransmitter vesicles as well as with some large dense core vesicles. Experiments using broad spectrum and residue-specific phosphatases indicated that a portion of ER? in synaptosomal fractions is phosphorylated at serine/threonine residues leading to a mobility shift in SDS-PAGE and creating a double band on Western blots. The phosphorylated form of ER? runs in the upper of the two bands and is particularly concentrated with synaptic vesicles. Finally, we used E2 with or without the acyl protein thioesterase 1 inhibitor, Palmostatin B, to show that 20 min of E2 treatment of hippocampal slices depletes ER? from the synaptosomal membrane by depalmitoylation. We found no evidence that E2 regulates phosphorylation of synaptosomal ER? on this time scale. These studies begin to fill the gap between detailed molecular characterization of extranuclear ER? in previous in vitro studies and acute E2 modulation of hippocampal synapses in the adult brain. PMID:23183182

Tabatadze, Nino; Smejkalova, Tereza



Carvedilol Prevents Ovariectomy-Induced Myocardial Contractile Dysfunction in Female Rat  

PubMed Central

Carvedilol has beneficial effects on cardiac function in patients with heart failure but its effect on ovariectomy-induced myocardial contractile dysfunction remains unclear. Estrogen deficiency induces myocardial contractile dysfunction and increases cardiovascular disease risk in postmenopausal women. Our aim was to investigate whether carvedilol, a beta receptor blocker, would prevent ovariectomy-induced myocardial contractile dysfunction. Female rats (8 weeks old) that underwent bilateral ovariectomy were randomly assigned to receive daily treatment with carvedilol (OVX+CAR, 20 mg/kg), placebo (OVX) and SHAM for 58 days. Left ventricle papillary muscle was mounted for isometric tension recordings. The inotropic response to Ca2+ (0.62 to 3.75 mM) and isoproterenol (Iso 10?8 to 10?2 M) were assessed. Expression of calcium handling proteins was measured by western blot analysis. Carvedilol treatment in the OVX animals: prevented weight gain and slight hypertrophy, restored the reduced positive inotropic responses to Ca2+ and isoproterenol, prevented the reduction in SERCA2a expression, abolished the increase in superoxide anion production, normalized the increase in p22phox expression, and decreased serum angiotensin converting enzyme (ACE) activity. This study demonstrated that myocardial contractile dysfunction and SERCA2a down regulation were prevented by carvedilol treatment. Superoxide anion production and NADPH oxidase seem to be involved in this response. PMID:23308166

Ribeiro, Rogerio Faustino; Potratz, Felipe F.; Pavan, Brunella M. M.; Forechi, Ludimila; Lima, Filipe Lugon Moulin; Fiorim, Jonaina; Fernandes, Aurelia Araujo; Vassallo, Dalton Valentim; Stefanon, Ivanita



Estradiol regulates large dense core vesicles in the hippocampus of adult female rats.  


Previous work has shown that the steroid hormone estradiol facilitates the release of anticonvulsant neuropeptides from inhibitory neurons in the hippocampus to suppress seizures. Because neuropeptides are packaged in large dense core vesicles, estradiol may facilitate neuropeptide release through regulation of dense core vesicles. In the current study, we used serial section electron microscopy in the hippocampal CA1 region of adult female rats to test three hypotheses about estradiol regulation of dense core vesicles: (1) Estradiol increases the number of dense core vesicles in axonal boutons, (2) Estradiol increases the size of dense core vesicles in axonal boutons, (3) Estradiol shifts the location of dense core vesicles toward the periphery of axonal boutons, potentially lowering the threshold for neuropeptide release during seizures. We found that estradiol increases the number and size of dense core vesicles in inhibitory axonal boutons, consistent with increased neuropeptide content, but does not shift the location of dense core vesicles closer to the bouton periphery. These effects were specific to large dense core vesicles (>80 nm) in inhibitory boutons. Estradiol had no effects on small dense core vesicles or dense core vesicles in excitatory boutons. Our results indicate that estradiol suppresses seizures at least in part by increasing the potentially releasable pool of neuropeptides in the hippocampus, and that estradiol facilitation of neuropeptide release involves a mechanism other than mobilization of dense core vesicles toward sites of release. PMID:23893355

May, Renee M; Tabatadze, Nino; Czech, Mary M; Woolley, Catherine S



Biochemical and morphological studies on perivenous and periportal liver parenchymal cells from female rats isolated by digitonin-collagenase method.  


Periportal (pp) or perivenous (pv) liver parenchymal cells from female adult Uje: WIST rats were isolated after retro- or antegrade digitonin infusion followed by collagenase perfusion in the opposite direction. The morphological results revealed a distinct acinar-related destruction of the pv- or pp-zone by digitonin. The remaining cells of the respective other zone showed a good structural maintenance. After subsequent conventional collagenase perfusion the yield, viability and structural integrity of the isolated hepatocytes were high. The zonal cell separation was indicated by significant differences in the pp marker glucose-6-phosphatase and the pv marker glutamine synthetase found in the isolated pp or pv cell populations. Under our experimental conditions including the use of female rats, the alanine aminotransferase and glutamate dehydrogenase as well as ethylmorphine N-demethylase and ethoxycoumarin O-deethylase activities were evenly distributed in both preparations. Under stimulating conditions the capacity for urea synthesis was similar in both pv and pp cells. PMID:1680746

Köhler, T; Müller, D; Franke, H; Machnik, G; Müller, D; Zimmermann, T



Role of the Vomeronasal Organ in the Male-Induced Enhancement of Sexual Receptivity in Female Rats  

Microsoft Academic Search

The role of the vomeronasal organ (VNO) in the male-induced enhancement of sexual receptivity in ovariectomized estrogen-primed rats was investigated. Removal of the VNO significantly reduced the enhancement of sexual receptivity following mating, as compared with the sham-operated controls. The sham-operated females exhibited a surge of luteinizing hormone (LH) following mating; however, LH release induced by pairing with males was

Gopalan Rajendren; Carol A. Dudley; Robert L. Moss



Comparison of the action of lysergic acid diethylamide and apomorphine on the copulatory response in the female rat  

Microsoft Academic Search

The effects of lysergic acid diethylamide (LSD) and apomorphine were compared using female copulatory behavior (lordosis response), in ovariectomized estrogen + progesterone-treated rats. Both serotonin and dopamine are implicated in the inhibition of this behavior. Each compound inhibited lordosis behavior dose dependently and with a similar time-course. Pimozide (0.1; 0.5 mg\\/kg) blocked the apomorphine (0.2 mg\\/kg)-induced decrease of lordosis response,

Mona Eliasson; Bengt J. Meyerson



The free-exploratory paradigm as a model of trait anxiety in female rats: test-retest reliability.  


The free-exploratory paradigm has been proposed as a model of trait anxiety and as such has been proven stable over time, which is a sine qua non condition for any model proposing to evaluate a personality trait. However this stability has only been shown for male rats. Considering that anxiety disorders are most prevalent in women, it's crucial that females are tested in animal models. With this in mind, the stability over time of female rats in the free-exploratory paradigm was evaluated using a test-retest procedure. The behaviour of drug-naive, adult, female, Wistar rats was measured in the free-exploratory apparatus on two occasions two months apart. The following parameters were evaluated: percentage of distance travelled in the novel compartment; number of attempts to enter the novel compartment; percentage of time spent in the novel compartment; and percentage of time rearing in the novel compartment. Subsequently, the intraclass correlation coefficient (ICC) and the kappa index (?) were calculated for each of these parameters. The "percentage of time spent in the novel compartment" (ICC=0.727; ?=0.457), the "percentage of distance travelled in the novel compartment" (ICC=0.680; ?=0.370), and the "percentage of time rearing in the novel compartment" (ICC=0.648; ?=0.309) were found to be stable over time. Analysis of these parameters indicated fair to substantial reliability over time in two-month inter-trial interval. Therefore, our results support the idea of the free-exploratory paradigm as an animal model of trait anxiety for female rats. PMID:25123445

Oliveira, Débora Ramiro de; Goes, Tiago Costa; Teixeira-Silva, Flavia



Blood pressure and heart rate changes during pregnancy in fructose-fed Sprague-Dawley rats.  


Blood pressure and heart rate changes during pregnancy were investigated in fructose-fed (diabetic) Sprague-Dawley rats. A total of 48 pubertal female rats were used. The experimental rats were fed with 25% (w/w) fructose mixed with normal rat chow for minimum period of 3 weeks while the control rats were fed with the normal rat chow. They all had free access to drinking water. Systolic, diastolic and mean arterial blood pressures and the heart rates were measured in both non-pregnant and pregnant control rats and their diabetic counterparts. The results indicate that systolic blood pressures significantly increased progressively during pregnancy in fructose-fed rats as compared with the non-pregnant rats (P < 0.0001) while in the control rats, except for the 2nd trimester sub-group, which had a similar value with the non-pregnant sub-group, the systolic blood pressure (SBP) also, increased steadily. When the diabetic group is compared with the control group, the SBP (in the 2nd trimester sub-groups) was raised from 82.18 +/- 1.26 mmHg in control rats to 112.48 +/- 1.26 mmHg in the diabetic rats (P < 0.0001). Diastolic blood pressure (DBP) progressively increased significantly in the diabetic rats from 63.94 +/- 3.95 mmHg in the non-pregnant sub-group to 91.95 +/- 1.89 mmHg in the 3rd trimester sub-group of the pregnant rats (P < 0.0001). The DBP of the 2nd trimester sub-group of the diabetic rats was significantly raised from 61.88 +/- 4.20 mmHg in the control rats to 89.60 +/- 1.79 mmHg in the diabetic rats (P < 0.0001). In addition, the mean arterial blood pressure (MAP) was significantly raised in the 1st and 2nd trimester of the diabetic rats from 70.61 +/- 3.12 mmHg in the non-pregnant diabetic rats to 96.28 +/- 1.36 mmHg and 97.13 +/- 1.15 mmHg respectively, (P < 0.0001, P < 0.0001). There was a progressive increase in the heart rates, in both control and diabetic groups, from non-pregnant sub-groups to the 3 trimesters of pregnancy. The body weights of the 2 groups of rats increased significantly as pregnancy progressed. These results suggest that fructose-induced diabetes could cause the development of sustained hypertension during pregnancy via the insulin-resistance-hyperinsulinemia-link. PMID:14510126

Olatunji-Bello, I I; Nwachukwu, D; Adegunloye, B J



Gonadotropin-inhibitory hormone promoter-driven enhanced green fluorescent protein expression decreases during aging in female rats.  


Gonadotropin-inhibitory hormone (GnIH) neurons project to GnRH neurons to negatively regulate reproductive function. To fully explore the projections of the GnIH neurons, we created transgenic rats carrying an enhanced green fluorescent protein (EGFP) tagged to the GnIH promoter. With these animals, we show that EGFP-GnIH neurons are localized mainly in the dorsomedial hypothalamic nucleus (DMN) and project to the hypothalamus, telencephalon, and diencephalic thalamus, which parallels and confirms immunocytochemical and gene expression studies. We observed an age-related reduction in c-Fos-positive GnIH cell numbers in female rats. Furthermore, GnIH fiber appositions to GnRH neurons in the preoptic area were lessened in middle-aged females (70 weeks old) compared with their younger counterparts (9-12 weeks old). The fiber density in other brain areas was also reduced in middle-aged female rats. The expression of estrogen and progesterone receptors mRNA in subsets of EGFP-GnIH neurons was shown in laser-dissected single EGFP-GnIH neurons. We then examined estradiol-17? and progesterone regulation of GnIH neurons, using c-Fos presence as a marker. Estradiol-17? treatment reduced c-Fos labeling in EGFP-GnIH neurons in the DMN of young ovariectomized adult females but had no effect in middle-aged females. Progesterone had no effect on the number of GnIH cells positive for c-Fos. We conclude that there is an age-related decline in GnIH neuron number and GnIH inputs to GnRH neurons. We also conclude that the response of GnIH neurons to estrogen diminishes with reproductive aging. PMID:24605826

Soga, Tomoko; Kitahashi, Takashi; Clarke, Iain J; Parhar, Ishwar S



Characterization of recovery, repair, and inflammatory processes following contusion spinal cord injury in old female rats: is age a limitation?  

PubMed Central

Background Although the incidence of spinal cord injury (SCI) is steadily rising in the elderly human population, few studies have investigated the effect of age in rodent models. Here, we investigated the effect of age in female rats on spontaneous recovery and repair after SCI. Young (3 months) and aged (18 months) female rats received a moderate contusion SCI at T9. Behavioral recovery was assessed, and immunohistocemical and stereological analyses performed. Results Aged rats demonstrated greater locomotor deficits compared to young, beginning at 7 days post-injury (dpi) and lasting through at least 28 dpi. Unbiased stereological analyses revealed a selective increase in percent lesion area and early (2 dpi) apoptotic cell death caudal to the injury epicenter in aged versus young rats. One potential mechanism for these differences in lesion pathogenesis is the inflammatory response; we therefore assessed humoral and cellular innate immune responses. No differences in either acute or chronic serum complement activity, or acute neutrophil infiltration, were observed between age groups. However, the number of microglia/macrophages present at the injury epicenter was increased by 50% in aged animals versus young. Conclusions These data suggest that age affects recovery of locomotor function, lesion pathology, and microglia/macrophage response following SCI. PMID:25512759




EPA Science Inventory

Endocrine-disrupting chemicals: prepubertal exposures and effects on sexual maturation and thyroid activity in the female rat. A focus on the EDSTAC recommendations. Goldman JM, Laws SC, Balchak SK, Cooper RL, Kavlock RJ. Reproductive Toxicology Division, National H...


Early exposure to bisphenol A alters neuron and glia number in the rat prefrontal cortex of adult males, but not females.  


Previous work has shown that exposure to bisphenol A (BPA) during early development can alter sexual differentiation of the brain in rodents, although few studies have examined effects on areas of the brain associated with cognition. The current study examined if developmental BPA exposure alters the total number of neurons and glia in the medial prefrontal cortex (mPFC) in adulthood. Pregnant Long-Evans rats were orally exposed to 0, 4, 40, or 400-?g/kg BPA in corn oil throughout pregnancy. From postnatal days 1 to 9, pups were given daily oral doses of oil or BPA, at doses corresponding to those given during gestation. Brains were examined in adulthood, and the volume of layers 2/3 and layers 5/6 of the mPFC was parcellated. The density of neurons and glia in these layers was quantified stereologically with the optical disector, and density was multiplied by volume for each animal. Males exposed to 400-?g/kg BPA were found to have increased numbers of neurons and glia in layers 5/6. Although there were no significant effects of BPA in layers 2/3, the pattern of increased neuron number in males exposed to 400-?g/kg BPA was similar to that seen in layers 5/6. No effects of BPA were seen in females or in males exposed to the other doses of BPA. This study indicates that males are more susceptible to the long-lasting effects of BPA on anatomy of the mPFC, an area implicated in neurological disorders. PMID:25193849

Sadowski, R N; Wise, L M; Park, P Y; Schantz, S L; Juraska, J M



PGC1?-mediated Mitofusin-2 Deficiency in Female Rats and Humans with Pulmonary Arterial Hypertension  

PubMed Central

Rationale: Pulmonary arterial hypertension (PAH) is a lethal, female-predominant, vascular disease. Pathologic changes in PA smooth muscle cells (PASMC) include excessive proliferation, apoptosis-resistance, and mitochondrial fragmentation. Activation of dynamin-related protein increases mitotic fission and promotes this proliferation–apoptosis imbalance. The contribution of decreased fusion and reduced mitofusin-2 (MFN2) expression to PAH is unknown. Objectives: We hypothesize that decreased MFN2 expression promotes mitochondrial fragmentation, increases proliferation, and impairs apoptosis. The role of MFN2’s transcriptional coactivator, peroxisome proliferator-activated receptor ? coactivator 1-? (PGC1?), was assessed. MFN2 therapy was tested in PAH PASMC and in models of PAH. Methods: Fusion and fission mediators were measured in lungs and PASMC from patients with PAH and female rats with monocrotaline or chronic hypoxia+Sugen-5416 (CH+SU) PAH. The effects of adenoviral mitofusin-2 (Ad-MFN2) overexpression were measured in vitro and in vivo. Measurements and Main Results: In normal PASMC, siMFN2 reduced expression of MFN2 and PGC1?; conversely, siPGC1? reduced PGC1? and MFN2 expression. Both interventions caused mitochondrial fragmentation. siMFN2 increased proliferation. In rodent and human PAH PASMC, MFN2 and PGC1? were decreased and mitochondria were fragmented. Ad-MFN2 increased fusion, reduced proliferation, and increased apoptosis in human PAH and CH+SU. In CH+SU, Ad-MFN2 improved walking distance (381 ± 35 vs. 245 ± 39 m; P < 0.05); decreased pulmonary vascular resistance (0.18 ± 0.02 vs. 0.38 ± 0.14 mm Hg/ml/min; P < 0.05); and decreased PA medial thickness (14.5 ± 0.8 vs. 19 ± 1.7%; P < 0.05). Lung vascularity was increased by MFN2. Conclusions: Decreased expression of MFN2 and PGC1? contribute to mitochondrial fragmentation and a proliferation–apoptosis imbalance in human and experimental PAH. Augmenting MFN2 has therapeutic benefit in human and experimental PAH. PMID:23449689

Ryan, John J.; Marsboom, Glenn; Fang, Yong-Hu; Toth, Peter T.; Morrow, Erik; Luo, Nancy; Piao, Lin; Hong, Zhigang; Ericson, Kyle; Zhang, Hannah J.; Han, Mei; Haney, Chad R.; Chen, Chin-Tu; Sharp, Willard W.



Feeding soy protein isolate (SPI) does not result in an estrogenic gene expression profile in the mammary of ovariectomized (OVX) female rats  

Technology Transfer Automated Retrieval System (TEKTRAN)

Concerns of increased breast cancer risk in women consuming soy exist because of the perceived estrogenicity of soy isoflavones. Female Sprague-Dawley rats (N equals 20/group) were fed AIN-93G diets with casein or SPI as the protein from PND30. On PND50 rats were OVX and 10/group infused s.c. with 5...


Modulation of Protein Kinases and Microtubule-associated Proteins and Changes in Ultrastructure in Female Rat Pituitary Cells: Effects of Estrogen and Bromocriptine  

Microsoft Academic Search

SUMMARY This study focused on the intracellular signal transduction system and micro- tubule-associated proteins (MAPs), such as MAP-2 and Tau protein. The modulation of these proteins and their correlation with ultrastructural changes were investigated in rat pituitary prolactin (PRL) cells. Adult female Wistar rats were treated with estrogen and bro- mocriptine and their pituitary glands were removed for analysis of

Akira Matsuno; Susumu Takekoshi; Naoko Sanno; Hirotoshi Utsunomiya; Yoshitaka Ohsugi; Nobuhito Saito; Hideaki Kanemitsu; Akira Tamura; Tadashi Nagashima; R. Yoshiyuki Osamura; Keiichi Watanabe



Rodent ultrasonic communication: Male prosocial 50-kHz ultrasonic vocalizations elicit social approach behavior in female rats (Rattus norvegicus).  


Rats emit distinct types of ultrasonic vocalizations (USV), which serve as situation-dependent affective signals with important communicative functions. Low-frequency 22-kHz USV typically occur in aversive situations, such as social defeat, whereas high-frequency 50-kHz USV can be observed in appetitive situations, like rough-and-tumble-play in juveniles or mating in adults. The 2 main USV types serve distinct communicative functions and induce call-specific behavioral responses in the receiver. While 22-kHz USV probably serve as alarm calls, 50-kHz USV appear to serve a prosocial communicative function in the sexual and the nonsexual context. In the sexual context, however, this view has recently been challenged by playback studies where only very limited behavioral changes were observed in response to prosocial 50-kHz USV. The aim of the present study was therefore to test whether female rats display social approach behavior in response to male prosocial 50-kHz USV by means of our established playback paradigm. To this aim, we exposed female rats to playback of the following 2 acoustic stimuli: (a) natural male 50-kHz USV and (b) time- and amplitude-matched white noise, with the latter serving as acoustic control for novelty-induced changes in behavior not linked to the communicative function of male prosocial 50-kHz USV. Our present findings show that female rats display high levels of social approach behavior in response to male prosocial 50-kHz USV, but not time- and amplitude-matched white noise, supporting the conclusion that male prosocial 50-kHz USV are likely to play an important role in establishing social proximity and possibly regulate mating behavior. PMID:24188619

Willadsen, Maria; Seffer, Dominik; Schwarting, Rainer K W; Wöhr, Markus



Impact of Neonatal Manipulation of Androgen Receptor Function on Endocrine-Metabolic Programming in the Juvenile Female Rat  

PubMed Central

The impact of neonatal androgen receptor (AR) stimulation/blockage, due to testosterone propionate (TP)/AR antagonist treatment, on individual anthropometry and neuroendocrine-metabolic function was evaluated in the juvenile female rat. Pups (age 5 days) were s.c. injected with TP (1.25?mg), flutamide (F; 1.75?mg), and TP?+?F or vehicle (control, CT) and studied on day 30 of age. Body weight (BW), parametrial adipose tissue (PMAT) mass, food intake, adipoinsular axis, and steroidogenic functions were examined. Opposite to TP-rats, F-treated rats developed hypophagia, grew slowly (BW and PMAT), and displayed heightened peripheral insulin sensitivity. These F effects were abrogated in TP?+?F animals. Accordingly, TP rats displayed hyperleptinemia, an effect fully prevented by F cotreatment. Finally, androgen-treated animals bore an irreversible ovarian dysfunction (reduced circulating levels of 17HOP4 and ovary 17HOP4 content and P450c17 mRNA abundance). These data indicate that early stimulation of AR enhanced energy store, blockage of AR activity resulted in some beneficial metabolic effects, and neonatally androgenized rats developed a severe ovarian dysfunction. Our study highlights the important role of AR in the early organizational programming of metabolic and neuroendocrine functions. PMID:24066237

Giovambattista, Andres



Genistein exposure during the early postnatal period favors the development of obesity in female, but not male rats.  


Genistein (Gen), the primary isoflavone in soy, has been shown to adversely affect various endocrine-mediated endpoints in rodents and humans. Soy formula intake by human infants has been associated with early age at menarche and decreased female-typical behavior in girls. Adipose deposition and expansion are also hormonally regulated and Gen has been shown to alter these processes. However, little is known about the impact of early-life soy intake on metabolic homeostasis in adulthood. The current study examined the impact of early-life Gen exposure on adulthood body composition (by magnetic resonance imaging) and the molecular signals mediating adipose expansion. From postnatal day (PND) 1 to 22, rat pups were daily orally dosed with 50mg/kg Gen to mimic blood Gen levels in human infants fed soy formula. Female but not male Gen-exposed rats had increased fat/lean mass ratio, fat mass, adipocyte size and number, and decreased muscle fiber perimeter. PND22 Gen-exposed females, but not males, had increased expression of adipogenic factors, including CCAAT/enhancer binding protein alpha (Cebp?), CCAAT/enhancer binding protein beta (Cebp?), and peroxisome proliferator-activated receptor gamma (Ppar?). Furthermore, Wingless-related MMTV integration site 10b (Wnt10b), a critical regulator of adipogenic cell fate determination, was hypermethylated and had decreased expression in adipose of PND22 Gen-exposed females. These data suggest that developmental Gen exposure in rats has gender-specific effects on adiposity that closely parallel the effects of a postweaning high-fat diet and underscore the importance of considering timing of exposure and gender when establishing safety recommendations for early-life dietary Gen intake. PMID:24361872

Strakovsky, Rita S; Lezmi, Stéphane; Flaws, Jodi A; Schantz, Susan L; Pan, Yuan-Xiang; Helferich, William G



Comparison of pregnant and non-pregnant occupant crash and injury characteristics based on national crash data.  


The objective of this study was to provide specific characteristics of injuries and crash characteristics for pregnant occupants from the National Automotive Sampling System/Crashworthiness Data System (NASS/CDS) database for pregnant women as a group, broken down by trimester, and compared to non-pregnant women. Using all NASS/CDS cases collected between the years 2000 and 2012 with at least one pregnant occupant, the entire pregnant data set included 321,820 vehicles, 324,535 occupants, and 640,804 injuries. The pregnant occupant data were compared to the characteristics of NASS/CDS cases for 14,719,533 non-pregnant females 13-44 years old in vehicle crashes from 2000 to 2012. Sixty five percent of pregnant women were located in the front left seat position and roughly the same percentage of pregnant women was wearing a lap and shoulder belt. The average change in velocity was 11.6mph for pregnant women and over 50% of crashes for pregnant women were frontal collisions. From these collisions, less than seven percent of pregnant women sustained MAIS 2+ injuries. Minor differences between the pregnant and non-pregnant occupants were identified in the body region and source of injuries sustained. However, the data indicated no large differences in injury or crash characteristics based on trimester of pregnancy. Moreover, the risk of an MAIS 2+ level injury for pregnant occupants is similar to the risk of injury for non-pregnant occupants based on the total vehicle change in velocity. Overall this study provides useful data for researchers to focus future efforts in pregnant occupant research. Additionally, this study reinforces that more detailed and complete data on pregnant crashes needs to be collected to understand the risk for pregnant occupants. PMID:25463946

Manoogian, Sarah



Estrogen replacement therapy in diabetic ovariectomized female rats potentiates postischemic leukocyte adhesion in cerebral venules via a RAGE-related process  

PubMed Central

In this study, we tested the hypothesis that the documented transformation of 17?-estradiol (E2) from a counterinflammatory hormone in nondiabetic (ND) rats to a proinflammatory agent in rats with diabetes mellitus (DM) is due to an enhanced contribution from the receptor for advanced glycation end products (RAGE). Rhodamine 6G-labeled leukocytes were observed through a closed cranial window in rats. In vivo pial venular leukocyte adherence and infiltration were measured over 10 h reperfusion after transient forebrain ischemia in DM (streptozotocin) versus ND intact, ovariectomized (OVX), and E2-replaced (for 7–10 days) OVX (OVE) females. The role of RAGE was examined in two ways: 1) RAGE knockdown via topical application of RAGE antisense versus missense oligodeoxynucleotide or 2) intracerebroventricular injection of the RAGE decoy inhibitor, soluble RAGE. Among diabetic rats, the lowest levels of cortical RAGE mRNA and immunoreactivity of the RAGE ligand, AGE, were seen in OVX females, with significantly higher levels exhibited in intact and OVE females. However, results from the analysis of cortical RAGE protein only partially tracked those findings. When comparing ND to DM rats, cortical AGE immunoreactivity was significantly lower in OVE and intact females but similar in OVX rats. In DM rats, the level of postischemic leukocyte adhesion and infiltration (highest to lowest) was OVE > intact >> untreated OVX. In NDs, adhesion was highest in the untreated OVX group. Leukocyte extravasation was observed at >6 h postischemia but only in diabetic OVE and intact females and in ND OVX (untreated) rats. Pretreatment with RAGE antisense-oligodeoxynucleotide or soluble RAGE attenuated postischemic leukocyte adhesion and prevented infiltration but only in the diabetic OVE and intact groups. These results indicate that the exacerbation of postischemic leukocyte adhesion by chronic E2 replacement therapy in diabetic OVX females involves a RAGE-related mechanism. Targeting RAGE may restore the neuroprotective effect of E2 replacement therapy in diabetic females. PMID:19820198

Xu, Hao-Liang; Vetri, Francesco; Lee, Hae-Kyung; Ye, Shuhua; Paisansathan, Chanannait; Mao, Lizhen; Tan, Fulong



Adverse effects of high-intensity sweeteners on energy intake and weight control in male and obesity-prone female rats  

PubMed Central

The use of high-intensity sweeteners has been proposed as a method to combat increasing rates of overweight and obesity in the human population. However, previous work with male rats suggests that consumption of such sweeteners might contribute to, rather than ameliorate, weight gain. The goals of the present experiments were to assess whether intake of high-intensity sweeteners is associated with increased food intake and body weight gain in female rats; to evaluate whether this effect depends on composition of the maintenance diet (i.e., standard chow compared to diets high in energy, fat and sugar [HE diets]); and to determine whether the phenotype of the rats with regard to propensity to gain weight on HE diets affects the consequences of consuming high-intensity sweeteners. The data demonstrated that female rats fed a low-fat, standard laboratory chow diet did not gain extra weight when fed yogurt dietary supplements sweetened with saccharin compared to those fed glucose-sweetened dietary supplements. However, female rats maintained on a “Westernized” diet high in fat and sugar (HE diet) showed significant increases in energy intake, weight gain and adiposity when given saccharin-sweetened compared to glucose-sweetened yogurt supplements. These differences were most pronounced in female rats known to be prone to obesity prior to the introduction of the yogurt diets. Both selectively-bred Crl:OP[CD] rats, and outbred Sprague-Dawley rats fed an HE diet showing high levels of weight gain (DIO rats) had increased weight gain in response to consuming saccharin-sweetened compared to glucose-sweetened supplements. However, in male rats fed an HE diet, saccharin-sweetened supplements produced extra weight gain regardless of obesity phenotype. These results suggest that the most negative consequences of consuming high-intensity sweeteners may occur in those most likely to use them for weight control, females consuming a “Westernized” diet and already prone to excess weight gain. PMID:23398432

Swithers, Susan E.; Sample, Camille H.; Davidson, T.L.



Neonatal citalopram exposure decreases serotonergic fiber density in the olfactory bulb of male but not female adult rats  

PubMed Central

Manipulation of serotonin (5HT) during early development has been shown to induce long-lasting morphological changes within the raphe nuclear complex and serotonergic circuitry throughout the brain. Recent studies have demonstrated altered raphe-derived 5HT transporter (SERT) immunoreactive axonal expression in several cortical target sites after brief perinatal exposure to selective 5HT reuptake inhibitors such as citalopram (CTM). Since the serotonergic raphe nuclear complex projects to the olfactory bulb (OB) and perinatal 5HT disruption has been shown to disrupt olfactory behaviors, the goal of this study was to further investigate such developmental effects in the OB of CTM exposed animals. Male and female rat pups were exposed to CTM from postnatal day 8–21. After animals reach adulthood (>90 days), OB tissue sections were processed immunohistochemically for SERT antiserum. Our data revealed that the density of the SERT immunoreactive fibers decreased ~40% in the OB of CTM exposed male rats, but not female rats. Our findings support a broad and long-lasting change throughout most of the 5HT system, including the OB, after early manipulation of 5HT. Because dysfunction of the early 5HT system has been implicated in the etiology of neurodevelopmental disorders such as autism spectrum disorders (ASDs), these new findings may offer insight into the abnormal olfactory perception often noted in patients with ASD. PMID:23675318

Zhang, Junlin; Dennis, Katie A.; Darling, Ryan D.; Alzghoul, Loai; Paul, Ian A.; Simpson, Kimberly L.; Lin, Rick C. S.



Induction of heme oxygenase-1 shifts the balance from proinjury to prosurvival in the placentas of pregnant rats with reduced uterine perfusion pressure.  


Placental hypoxia/ischemia has been implicated as a central factor in the development of preeclampsia. One particularly useful animal model to study the impact of placental ischemia is the reduced uterine perfusion pressure (RUPP) model. We have previously demonstrated that RUPP animals exhibit elevated placental oxidative stress, which plays an important role in the development of the associated maternal hypertension. Recently, we have demonstrated that cobalt protoporphyrin (CoPP)-mediated induction of heme oxygenase-1 (HO-1) attenuates RUPP-induced oxidative stress and consequent hypertension. However, signaling pathways that are involved in this process are virtually unknown. Here, we show that placentas from RUPP animals exhibit increased phosphorylation of JNK, STAT1, STAT3, and p52shc with a concomitant increase in caspase-3 activation and depletion of intracellular ATP. Treatment with CoPP decreased RUPP-induced phosphorylation of JNK and STAT1, while it increased phosphorylation of ERK and STAT3, leading to decreased caspase-3 activation and restoration of intracellular ATP content. Our data imply that RUPP induces oxidative stress and the consequent injurious state by increasing phosphorylation of mediators of injury (STAT1, JNK) and, to a lesser extent, survival (STAT3, p52shc) in placentas of pregnant rats. HO-1 induction shifts this balance to a prosurvival phenotype by augmenting phosphorylation of the prosurvival ERK and STAT3, while suppressing phosphorylation of JNK and STAT1. This attenuates the resulting injury, as indicated by caspase-3 activation and ATP depletion. These results demonstrate a novel therapeutic activity of HO-1 induction in placental cell survival during ischemia and support the HO-1 pathway as a promising therapeutic target for the management of preeclampsia. PMID:22237591

George, Eric M; Arany, Istvan



Effects of Post-coital Administration of Alkaloids from Senna alata (Linn. Roxb) Leaves on some Fetal and Maternal Outcomes of Pregnant Rats  

PubMed Central

Background The abortifacient claim of Senna alata (S. alata) was scientifically validated recently with alkaloids speculated to be the bioactive agent. This speculation is yet to be substantiated or refuted by scientific evidence. The present study was aimed to investigate the pregnancy terminating effects of the alkaloids from S. alata leaves. Methods Twenty four Pregnant rats (143.99±1.21 g) allocated randomly to four groups: A, B, C and D respectively received, 0.5 ml of distilled water, 250, 500 and 1000 mg/kg body weight of the S. alata extracted alkaloids orally, once daily from day 10 until day 18 post-coitum. The indices of abortifacient were evaluated at the end of the exposure period. The results were analyzed by both the analysis of variance and Duncan's multiple range test and p < 0.05 was considered as statistically significant. Results Thin-layer chromatographic separation produced five spots with Rf values of 0.28, 0.33, 0.39, 0.47 and 0.55 which gave positive reaction with Meyer's and Wagner's reagents, respectively. The number of implantation sites and corpora lutea, as well as the concentrations of FSH, LH, progesterone, weight of uterus, uterine/ body weight ratio, glucose and cholesterol decreased significantly (p < 0.05) whereas the resorption index, pre- and post-implantation losses, uterine protein content and alkaline phosphatase activity increased significantly. None of the alkaloid treated animals presented with provoked vaginal opening or bleeding except fetal deaths. The alkaloid decreased the maternal weight gain, as well as feed and water intake. Conclusion Overall, the alkaloids from S. alata leaves exhibited anti-implantation, anti-gonadotropic, anti-progesteronic, embryonic resorptive, feto-maternal toxic activities but not complete abortifacient. The alkaloids alone may not be the sole abortifacient bioactive agent in the leaf extract. PMID:23926548

Yakubu, Musa Toyin; Musa, Isa Fakai



Modulation of steroidogenic pathway in rat granulosa cells with subclinical Cd exposure and insulin resistance: an impact on female fertility.  


Changes in lifestyle lead to insulin resistance (IR) in females ultimately predisposing them towards infertility. In addition, cadmium (Cd), an environmental endocrine disruptor, is reported for detrimental effects on granulosa cells, thus leading to ovarian dysfunction. A combination of these factors, lifestyle and environment, seems to play a role in etiology of idiopathic infertility that accounts for 50% amongst the total infertility cases. To address this issue, we made an attempt to investigate the extent of Cd impact on insulin-resistant (IR) granulosa cells. We exposed adult female Charles Foster rats to dexamethasone and confirmed IR condition by fasting insulin resistance index (FIRI). On treatment of IR rats with Cd, the preliminary studies demonstrated prolonged estrous cyclicity, decrease in serum estradiol concentrations, abnormal histology of ovary, and increased granulosa cell death. Further gene and protein expression studies of steroidogenic acute regulatory (StAR) protein, 17?-hydroxysteroid dehydrogenase (17?-HSD), and cytochrome P450 aromatase (CYP19A1) were performed. Protein expression studies demonstrated significant decrease in treated groups when compared with control. Study revealed that, in spite of the molecular parameters being affected at varied level, overall ovarian physiology is maximally affected in IR and Cd coexposed group, thus mimicking the condition similar to those prevailing in infertile females. PMID:25210711

Belani, Muskaan; Purohit, Nupur; Pillai, Prakash; Gupta, Sharad; Gupta, Sarita



Modulation of Steroidogenic Pathway in Rat Granulosa Cells with Subclinical Cd Exposure and Insulin Resistance: An Impact on Female Fertility  

PubMed Central

Changes in lifestyle lead to insulin resistance (IR) in females ultimately predisposing them towards infertility. In addition, cadmium (Cd), an environmental endocrine disruptor, is reported for detrimental effects on granulosa cells, thus leading to ovarian dysfunction. A combination of these factors, lifestyle and environment, seems to play a role in etiology of idiopathic infertility that accounts for 50% amongst the total infertility cases. To address this issue, we made an attempt to investigate the extent of Cd impact on insulin-resistant (IR) granulosa cells. We exposed adult female Charles Foster rats to dexamethasone and confirmed IR condition by fasting insulin resistance index (FIRI). On treatment of IR rats with Cd, the preliminary studies demonstrated prolonged estrous cyclicity, decrease in serum estradiol concentrations, abnormal histology of ovary, and increased granulosa cell death. Further gene and protein expression studies of steroidogenic acute regulatory (StAR) protein, 17?-hydroxysteroid dehydrogenase (17?-HSD), and cytochrome P450 aromatase (CYP19A1) were performed. Protein expression studies demonstrated significant decrease in treated groups when compared with control. Study revealed that, in spite of the molecular parameters being affected at varied level, overall ovarian physiology is maximally affected in IR and Cd coexposed group, thus mimicking the condition similar to those prevailing in infertile females. PMID:25210711

Belani, Muskaan; Purohit, Nupur; Pillai, Prakash; Gupta, Sharad; Gupta, Sarita



The effects of chronic mercuric chloride ingestion in female Sprague–Dawley rats on fertility and reproduction  

PubMed Central

Thirty-days-old female rats were chronically exposed, for 60 days, to 1or 2 mg/kg/day of mercuric chloride or an equivalent volume of water, via gavage. At 90 days of age they were mated with unexposed males. At approximately day 13 of gestation necropsies were performed on the females. Data were collected on the number of implantations and non-viable implantations in the uterus. No physical signs of Hg intoxication were seen except in weight gain. There were significantly fewer implantations in the high HgCl2 group, with significantly more non-viable implantations in the low and high HgCl2 groups, compared to controls. Lower levels of progesterone and higher levels of pituitary luteinizing hormone (LH) were found in the high HgCl2 group compared to controls, whereas pituitary follicle stimulating hormone levels (FSH), while not significant, showed a dose–response relationship to HgCl2 levels. No difference was found in the number of corpora lutea. The experiment indicated low level chronic ingestion of mercuric chloride, in female rats, while not effecting ovulation, produced disruption of implantation and fetal viability. Lower progesterone levels, higher LH, and possibly FSH levels, indicate that mercuric chloride may have a disruptive effect in the corpora lutea which manifests itself after ovulation. PMID:19371768

Heath, J.C.; Abdelmageed, Y.; Braden, T.D.; Nichols, A.C.; Steffy, D.A.



Maternal obesity and fetal programming: effects of a high-carbohydrate nutritional modification in the immediate postnatal life of female rats  

PubMed Central

Our earlier studies have shown that the artificial rearing of newborn rat pups [first generation high carbohydrate (1-HC)] on an HC milk formula resulted in chronic hyperinsulinemia and adult-onset obesity (HC phenotype). Offspring [second-generation HC (2-HC)] of 1-HC female rats spontaneously acquired the HC phenotype in the postweaning period. In this study, we have characterized the development of the abnormal intrauterine environment in the 1-HC female rats and the effects on fetal development under such pregnancy conditions for the offspring. 1-HC female rats demonstrated hyperphagia on laboratory chow and increased body weight gain beginning from the immediate postweaning period along with hyperinsulinemia and hyperleptinemia. During pregnancy, 1-HC female rats showed several metabolic alterations including increased body weight gain and increased plasma levels of insulin, leptin, proinflammatory markers, and lipid peroxidation products. Although there were no significant changes in the body weights or litter size of term 2-HC fetuses, the plasma levels of insulin and leptin were significantly higher compared with those of control term fetuses. Quantitation of mRNA levels by real-time RT-PCR indicated significant increases in the mRNA levels of orexigenic neuropeptides in the hypothalamus of 2-HC term fetuses. Collectively, these results indicate that the HC diet in infancy results in an adverse pregnancy condition in female rats with deleterious consequences for the offspring. PMID:18682533

Srinivasan, Malathi; Dodds, Catherine; Ghanim, Husam; Gao, Tao; Ross, Peter J.; Browne, Richard W.; Dandona, Paresh; Patel, Mulchand S.



Glycerol-3-phosphate dehydrogenase expression and oxygen consumption in liver mitochondria of female and male rats with chronic alteration of thyroid status.  


In our chronic experiments (over several months), the activity and protein amount of glycerol-3-phosphate dehydrogenase (GPDH) in mitochondria isolated from the liver of adult male and female inbred Lewis strain euthyroid (EU), hyperthyroid (TH), and hypothyroid (HY) rats were analyzed by biochemical and Western blot methods. The TH status was induced by intraperitoneal injections of 3,3',5-triiodo- L-thyronine and the HY status with 0.05% solution of methimazole in drinking water. The TH status led to a significant increase and the HY status to a significant decrease of enzyme activity and protein amount in both male and female animals. These changes were, however, more pronounced in females. The EU and TH female rats also showed a significantly higher activity and the TH female rats showed also a significantly higher enzyme amount in comparison with males, while the HY rats showed low levels in both sexes. The glycerol-3-phosphate-dependent oxygen consumption of freshly isolated rat liver mitochondria from the TH animals was higher in comparison with the EU animals and it was activated by idebenone, a synthetic analogue of coenzyme Q, in both the EU and TH rats. Measurements of serum thyroid hormone levels and analysis of anatomical parameters (relative heart and thyroid gland weights) confirmed that our procedures inducing the TH and HY states are efficient and reliable and that determination of GPDH can serve as an additional criterion for the evaluation of the thyroid hormone status. PMID:20886417

Rauchová, H; Mrácek, T; Novák, P; Vokurková, M; Soukup, T



Genotoxicity assessment of cerium oxide nanoparticles in female Wistar rats after acute oral exposure.  


Cerium oxide nanoparticles (CeO2 NPs; nanoceria) have demonstrated excellent potential for commercial use in various arenas, such as in biomedical industry in cosmetics and as a fuel additive. However, limited knowledge exists regarding their potential toxicity. In this study, acute oral toxicity of CeO2 NPs and their microparticles (MPs; bulk) was carried out in female albino Wistar rats. The CeO2 NPs and CeO2 MPs were characterized utilizing transmission electron microscopy (TEM), dynamic light scattering (DLS) and laser Doppler velocimetry (LDV) for the size, distribution and surface charge respectively. The genotoxicity studies were conducted using micronucleus test (MNT), comet and chromosomal aberration (CA) assays. Results revealed that at high dose (1000mg/kg bw) CeO2 NPs induced significant DNA damage in peripheral blood leukocytes (PBL) and liver cells, micronucleus formation in bone marrow and blood cells and total cytogenetic changes in bone marrow. However, significant genotoxicity was not observed at 500 and 100mg/kg bw of CeO2 NPs. The findings from biochemical assays depicted significant alterations in ALP and LDH activity in serum and GSH content in liver, kidneys and brain only at the high dose of CeO2 NPs. Tissue biodistribution of both particles was analyzed by inductively coupled plasma optical emission spectrometer (ICP-OES). Bioaccumulation of nanoceria in all tissues was significant and dose-, time- and organ-dependent. Moreover, CeO2 NPs exhibited higher tissue distribution along with greater clearance in large fractions through urine and feces than CeO2 bulk, whereas, maximum amount of micro-sized CeO2 got excreted in feces. The histopathological examination documented alterations in the liver due to exposure with CeO2 NPs only. Hence, the results suggest that bioaccumulation of CeO2 NPs may induce genotoxic effects. However, further research on long term fate and adverse effects of CeO2 NPs is warranted. PMID:25435351

Kumari, Monika; Kumari, Srinivas Indu; Kamal, Sarika Srinivas Kalyan; Grover, Paramjit




PubMed Central

Since the regression of the corpus luteum (CL) occurs via a tightly controlled apoptotic process, studies were designed to determine if local administration of the antiapoptotic agent sphingosine-1-phosphate (S1P) effectively blocks the luteolytic action of PGF-2alpha (PGF-2?). On day 19 of pregnancy, 2 h before systemic PGF-2? administration, rats were injected intrabursa with either S1P or vehicle (control). The activity of four caspases, which contribute to the initial (caspase-2, -8 and -9) and final (caspase-3) events in apoptosis was measured in pooled CL from 4 individual ovaries at 0 h and 4 h after PGF-2? injection. The expression of the phosphorylated form of AKT (pAKT) and TNF-? was analyzed by ELISA. In addition, cell death was evaluated by electronic microscopy (EM) in CL 4 and 36 h after PGF-2? injection. The activity of caspase-2, -3 and -8 was significantly greater by 4h after PGF-2? but not caspase-9 activity. In contrast, expression of pAKT and TNF-? decreased significantly. Administration of S1P suppressed (p<0.05) these effects, decreasing caspase activities and increasing pAKT and TNF-? expression. The administration of S1P also significantly decreased the percentage of luteal apoptotic cells induced by PGF-2?. PGF-2? treatment increased the prevalence of luteal cells with advanced signs of apoptosis (i.e. multiple nuclear fragments, chromatin condensation or apoptotic bodies). S1P treatment suppressed these changes and increased the blood vessel density. These results suggest that S1P blocks the luteolytic effect of the PGF-2? by decreasing caspase-2, -3 and -8 activities and increasing AKT phosphorylation and TNF- ? expression. PMID:19645054

Hernandez, Fatima; Peluffo, Marina C.; Bas, Diana; Stouffer, Richard L.; Tesone, Marta



The effect of purified compared with nonpurified diet on bone changes induced by hindlimb suspension of female rats  

NASA Technical Reports Server (NTRS)

The purpose of this study was to compare the bone changes induced by unloading in rats fed different diets, because space flight studies use a semipurified diet, whereas space flight simulation studies typically use nonpurified diets. Female Sprague-Dawley rats were fed a purified American Institute of Nutrition (AIN) 93G diet or a standard nonpurified diet and kept ambulatory or subjected to unloading by hindlimb suspension (HLS) for 38 days. Bone mineral content (BMC), mechanical strength, and factors related to the diet that affect bone (i.e., urinary calcium excretion, estradiol, and corticosterone) were measured. Average food intakes (grams per day) differed for diets, but caloric intake (kilocalories per day) and the final body masses of treatment groups were similar. The HLS-induced decrease in femoral BMC was not statistically different for rats fed a nonpurified diet (-8.6%) compared with a purified AIN-93G diet (-11.4%). The HLS-induced decrease in femoral mechanical strength was not statistically different for rats fed a nonpurified diet (-24%) compared with a purified AIN-93G diet (-31%). However, bone lengths were decreased (P < 0.05) in rats fed a nonpurified diet compared with a purified diet. Plasma estradiol levels were lower (P < 0.05) in the HLS/AIN-93G group but similar in the HLS and ambulatory rats fed a nonpurified diet. Plasma estradiol was related to femoral BMC (r = 0.85, P < 0.01). Urinary calcium excretion was higher (P < 0.05) in rats fed a nonpurified diet than those fed a purified AIN-93G diet, which is consistent with the higher level of calcium in the nonpurified diet. Urinary corticosterone levels were higher (P < 0.05) in rats fed a nonpurified diet than rats fed the AIN-93G diet. Although the osteopenia induced by unloading was similar in both diet groups, there were differences in longitudinal bone growth, calcium excretion, plasma estradiol levels, and urinary corticosterone levels. Results indicate that the type of standard diet used is an important factor to consider when measuring bone end points.

Tou, Janet C L.; Arnaud, Sara B.; Grindeland, Richard; Wade, Charles



[Effect of dietary protein deficiency in female rats on the function of the immunocompetent system of their progeny].  


The influence of alimentary protein deficiency, during early ontogenesis, on the morphofunctional characteristics of the immunocompetent system was studied in 115 experimental and 60 control female rats, 4 and 12 months after the commencement of the experiment. It was shown that protein deficiency in the period of prenatal ontogenesis induced significant changes in the humoral and cellular values, characterizing immunologic responsiveness and nonspecific resistance of the body, and leads to alteration of the morphological structure of the lymphoid organs. Such changes were also observed in the rats of the second generation, which received full-value food, thus evidencing grave and stable immunologic disorders as the result of protein deficiency during prenatal ontogenesis. PMID:3739311

Volgarev, M N; Sergeeva, K V; Trushina, E N; Tokareva, T V; Leshcheva, O A



Liver tumor formation in female rat induced by fluopyram is mediated by CAR/PXR nuclear receptor activation.  


Fluopyram is a broad spectrum fungicide targeting plant pathogenic fungi (eg. white dot, black mold, botrytis). During the general toxicity evaluation of fluopyram in rodents, the liver was identified as a target organ (hepatomegaly and liver hypertrophy were observed in all studies). At the end of the guideline carcinogenicity study, an increased incidence of hepatocellular adenomas and carcinomas was observed in female Wistar rats following exposure to the highest fluopyram dose evaluated (1500ppm). Short-term mechanistic studies (3, 7 or 28days of exposure) were conducted in the female rat to identify the initial key events responsible for the tumor formation and to establish thresholds for each of the early hepatic changes. Increased expression of constitutive androstane receptor (CAR) and pregnane X receptor (PXR) inducible genes was recorded after each exposure period. Further confirmation of CAR/PXR activation was provided by increased activity of specific Phase I enzymes (PROD/BROD respectively). Increased hepatocellular proliferation (measured by Ki67) was observed after each exposure period with the greatest proliferative response occurring after 3days of treatment. In these studies, dose responses and clear thresholds were established for gene expression, enzyme activity and cell proliferation. Furthermore, these early hepatic changes were shown to be reversible following compound withdrawal. Other modes of action for liver tumor formation such as DNA damage, cytotoxicity and peroxisome proliferation were excluded during the investigations. In conclusion, fluopyram is a threshold carcinogen and the resultant hepatocellular carcinomas in the female rat are due to hepatocellular proliferation mediated by CAR/PXR activation. PMID:25305127

Tinwell, H; Rouquié, D; Schorsch, F; Geter, D; Wason, S; Bars, R



dynorphin-kappa opioid receptor signaling partly mediates estrogen negative feedback effect on LH pulses in female rats.  


Accumulating evidence suggests that the arcuate nucleus (ARC) kisspeptin/neurokinin B (NKB)/dynorphin (KNDy) neurons play a role in estrogen negative feedback action on pulsatile gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) release. The present study aimed to determine if dynorphin (Dyn) is involved in estrogen negative feedback on pulsatile GnRH/LH release. The effect of the injection of nor-binaltorphimine (nor-BNI), a kappa-opioid receptor (KOR) antagonist, into the third cerebroventricle (3V) on LH pulses was determined in ovariectomized (OVX) adult female rats with/without replacement of negative feedback levels of estradiol (low E2). The mean LH concentrations and baseline levels of LH secretion in nor-BNI-injected, low E2-treated rats were significantly higher compared with vehicle-treated controls. On the other hand, the nor-BNI treatment failed to affect any LH pulse parameters in OVX rats without low E2 treatment. These results suggest that Dyn is involved in the estrogen negative feedback regulation of pulsatile GnRH/LH release. The low E2 treatment had no significant effect on the numbers of ARC Pdyn (Dyn gene)-,Kiss1- and Tac2 (NKB gene)-expressing cells. The treatment also did not affect mRNA levels of Pdyn and Oprk1 (KOR gene) in the ARC-median eminence region, but significantly increased the ARC kisspeptin immunoreactivity. These findings suggest that the negative feedback level of estrogen suppresses kisspeptin release from the ARC KNDy neurons through an unknown mechanism without affecting the Dyn and KOR expressions in the ARC. Taken together, the present result suggests that Dyn-KOR signaling is a part of estrogen negative feedback action on GnRH/LH pulses by reducing the kisspeptin release in female rats. PMID:23391862

Mostari, Parvin; Ieda, Nahoko; Deura, Chikaya; Minabe, Shiori; Yamada, Shunji; Uenoyama, Yoshihisa; Maeda, Kei-ichiro; Tsukamura, Hiroko



Dynorphin-Kappa Opioid Receptor Signaling Partly Mediates Estrogen Negative Feedback Effect on LH Pulses in Female Rats  

PubMed Central

Abstract Accumulating evidence suggests that the arcuate nucleus (ARC) kisspeptin/neurokinin B (NKB)/dynorphin (KNDy) neurons play a role in estrogen negative feedback action on pulsatile gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH) release. The present study aimed to determine if dynorphin (Dyn) is involved in estrogen negative feedback on pulsatile GnRH/LH release. The effect of the injection of nor-binaltorphimine (nor-BNI), a kappa-opioid receptor (KOR) antagonist, into the third cerebroventricle (3V) on LH pulses was determined in ovariectomized (OVX) adult female rats with/without replacement of negative feedback levels of estradiol (low E2). The mean LH concentrations and baseline levels of LH secretion in nor-BNI-injected, low E2-treated rats were significantly higher compared with vehicle-treated controls. On the other hand, the nor-BNI treatment failed to affect any LH pulse parameters in OVX rats without low E2 treatment. These results suggest that Dyn is involved in the estrogen negative feedback regulation of pulsatile GnRH/LH release. The low E2 treatment had no significant effect on the numbers of ARC Pdyn (Dyn gene)-,Kiss1- and Tac2 (NKB gene)-expressing cells. The treatment also did not affect mRNA levels of Pdyn and Oprk1 (KOR gene) in the ARC-median eminence region, but significantly increased the ARC kisspeptin immunoreactivity. These findings suggest that the negative feedback level of estrogen suppresses kisspeptin release from the ARC KNDy neurons through an unknown mechanism without affecting the Dyn and KOR expressions in the ARC. Taken together, the present result suggests that Dyn-KOR signaling is a part of estrogen negative feedback action on GnRH/LH pulses by reducing the kisspeptin release in female rats. PMID:23391862

MOSTARI, Mst. Parvin; IEDA, Nahoko; DEURA, Chikaya; MINABE, Shiori; YAMADA, Shunji; UENOYAMA, Yoshihisa; MAEDA, Kei-ichiro; TSUKAMURA, Hiroko



Prenatal ethanol exposure programs an increased susceptibility of non-alcoholic fatty liver disease in female adult offspring rats  

SciTech Connect

Prenatal ethanol exposure (PEE) induces dyslipidemia and hyperglycemia in fetus and adult offspring. However, whether PEE increases the susceptibility to non-alcoholic fatty liver disease (NAFLD) in offspring and its underlying mechanism remain unknown. This study aimed to demonstrate an increased susceptibility to high-fat diet (HFD)-induced NAFLD and its intrauterine programming mechanisms in female rat offspring with PEE. Rat model of intrauterine growth retardation (IUGR) was established by PEE, the female fetus and adult offspring that fed normal diet (ND) or HFD were sacrificed. The results showed that, in PEE + ND group, serum corticosterone (CORT) slightly decreased and insulin-like growth factor-1 (IGF-1) and glucose increased with partial catch-up growth; In PEE + HFD group, serum CORT decreased, while serum IGF-1, glucose and triglyceride (TG) increased, with notable catch-up growth, higher metabolic status and NAFLD formation. Enhanced liver expression of the IGF-1 pathway, gluconeogenesis, and lipid synthesis as well as reduced expression of lipid output were accompanied in PEE + HFD group. In PEE fetus, serum CORT increased while IGF-1 decreased, with low body weight, hyperglycemia, and hepatocyte ultrastructural changes. Hepatic IGF-1 expression as well as lipid output was down-regulated, while lipid synthesis significantly increased. Based on these findings, we propose a “two-programming” hypothesis for an increased susceptibility to HFD-induced NAFLD in female offspring of PEE. That is, the intrauterine programming of liver glucose and lipid metabolic function is “the first programming”, and postnatal adaptive catch-up growth triggered by intrauterine programming of GC-IGF1 axis acts as “the second programming”. - Highlights: • Prenatal ethanol exposure increase the susceptibility of NAFLD in female offspring. • Prenatal ethanol exposure reprograms fetal liver’s glucose and lipid metabolism . • Prenatal ethanol exposure cause the adaptive change of glucocorticoid-IGF1 axis.

Shen, Lang; Liu, Zhongfen; Gong, Jun; Zhang, Li [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Wang, Linlong [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Magdalou, Jacques [UMR 7561 CNRS-Nancy Université, Faculté de Médicine, Vandoeuvre-lès-Nancy (France); Chen, Liaobin [Department of Orthopedic Surgery, Zhongnan Hospital of Wuhan University, Wuhan 430071 (China); Wang, Hui, E-mail: [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan 430071 (China)



Estrogenic Regulation of Histamine Receptor Subtype H1 Expression in the Ventromedial Nucleus of the Hypothalamus in Female Rats  

PubMed Central

Female sexual behavior is controlled by central estrogenic action in the ventromedial nucleus of the hypothalamus (VMN). This region plays a pivotal role in facilitating sex-related behavior in response to estrogen stimulation via neural activation by several neurotransmitters, including histamine, which participates in this mechanism through its strong neural potentiating action. However, the mechanism through which estrogen signaling is linked to the histamine system in the VMN is unclear. This study was undertaken to investigate the relationship between estrogen and histamine receptor subtype H1 (H1R), which is a potent subtype among histamine receptors in the brain. We show localization of H1R exclusively in the ventrolateral subregion of the female VMN (vl VMN), and not in the dorsomedial subregion. In the vl VMN, abundantly expressed H1R were mostly colocalized with estrogen receptor ?. Intriguingly, H1R mRNA levels in the vl VMN were significantly elevated in ovariectomized female rats treated with estrogen benzoate. These data suggest that estrogen can amplify histamine signaling by enhancing H1R expression in the vl VMN. This enhancement of histamine signaling might be functionally important for allowing neural excitation in response to estrogen stimulation of the neural circuit and may serve as an accelerator of female sexual arousal. PMID:24805361

Mori, Hiroko; Matsuda, Ken-Ichi; Yamawaki, Masanaga; Kawata, Mitsuhiro




EPA Science Inventory

Using a known immunosuppresant, dexamethasone (DEX), pregnant Sprague Dawley (SD) rats were given subcutaneous (s.c.) injections of DEX (0.0, 0.0375, 0.075, 0.15, 0.3 mg/kg) during gestation days 6 to 21. Both male and female offspring were tested for immune dysfunction. In a ...


Changes in mRNA and protein expression in the renal cortex of male and female F344 rats treated with bromate.  


Bromate (BrO3(-)), a by-product of ozonation of drinking water, induces nephrotoxicity in male rats at much lower doses than in female rats. This difference appears to be related to the development of ?-2u-globulin nephropathy in males. To determine sex-dependent changes in mRNA and protein expression in the renal cortex attributable to ?-2u-globulin nephropathy, we performed microarray and immunohistochemical analyses in proximal renal tubules of male and female F344 rats treated with KBrO3 for 28 days. Particular attention was paid to molecular biomarkers of renal tubular injury. Microarray analysis of male and female rats treated with BrO3(-) at low doses (125 mg/L KBrO3) displayed marked sex-dependent changes in renal gene expression. The greatest differences were seen in genes encoding for cellular differentiation, apoptosis, ion transport, and cell proliferation. Differences by sex were especially prominent for the cell cycle checkpoint gene p21, the renal injury protein Kim-1, and the kidney injury and cancer biomarker protein osteopontin. Dose-related nephrotoxicity, assessed by hematoxylin and eosin staining, was greater in males compared to female rats, as was cellular proliferation, assessed by bromodeoxyuridine staining. The fraction of proximal renal cells with elevated 8-oxodeoxyguanosine (8-OH-dG) was only increased at the high dose and did not differ by sex. Dose-dependent increases in the expression of osteopontin were detected immunohistochemically only in male rats and were localized in proximal tubule cells. Similarly, BrO3(-) treatment increased clusterin and Kim-1 staining in the proximal tubules; however, staining for these proteins did not differ appreciably between males and females. These data demonstrate both qualitative and quantitative differences in the response of male versus female kidneys to BrO3(-)-treatment. These sex-dependent effects likely contribute to renal carcinogenesis of BrO3(-) in the male rat. PMID:23588252

Kolisetty, Narendrababu; Delker, Don A; Muralidhara, Srinivasa; Bull, Richard J; Cotruvo, Joseph A; Fisher, Jeff W; Cummings, Brian S



Testosterone and estradiol differentially affect cell proliferation in the subventricular zone of young adult gonadectomized male and female rats.  


Steroid hormones are important players to regulate adult neurogenesis in the dentate gyrus of the hippocampus, but their involvement in the regulation of the same phenomenon in the subventricular zone (SVZ) of the lateral ventricles is not completely understood. Here, in male rats, we tested the existence of activational effects of testosterone (T) on cell proliferation in the adult SVZ. To this aim, three groups of male rats: castrated, castrated and treated with T, and controls were treated with 5-bromo-2'-deoxyuridine (BrdU) and killed after 24h. The density of BrdU-labeled cells was significantly lower in castrated animals in comparison to the other two groups, thus supporting a direct correlation between SVZ proliferation and levels of circulating T. To clarify whether this effect is purely androgen-dependent, or mediated by the T metabolites, estradiol (E2) and dihydrotestosterone (DHT), we evaluated SVZ proliferation in castrated males treated with E2, DHT and E2+DHT, in comparison to T- and vehicle-treated animals, and sham-operated controls. The stereological analysis demonstrated that E2 and T, but not DHT, increase proliferation in the SVZ of adult male rats. Quantitative evaluation of cells expressing the endogenous marker of cell proliferation phosphorylated form of Histone H3 (PHH3), or the marker of highly dividing SVZ progenitors Mash1, indicated the effect of T/E2 is mostly restricted to SVZ proliferating progenitors. The same experimental protocol was repeated on ovariectomized female rats treated with E2 or T. In this case, no statistically significant difference was found among groups. Overall, our results clearly show that the gonadal hormones T and E2 represent important mediators of cell proliferation in the adult SVZ. Moreover, we show that such an effect is restricted to males, supporting adult neurogenesis in rats is a process differentially modulated in the two sexes. PMID:25481234

Farinetti, A; Tomasi, S; Foglio, B; Ferraris, A; Ponti, G; Gotti, S; Peretto, P; Panzica, G C



Postnatal treadmill exercise alleviates short-term memory impairment by enhancing cell proliferation and suppressing apoptosis in the hippocampus of rat pups born to diabetic rats  

PubMed Central

During pregnancy, diabetes mellitus exerts detrimental effects on the development of the fetus, especially the central nervous system. In the current study, we evaluated the effects of postnatal treadmill exercise on short-term memory in relation with cell proliferation and apoptosis in the hippocampus of rat pups born to streptozotocin (STZ)-induced diabetic maternal rats. Adult female rats were mated with male rats for 24 h. Two weeks after mating, the pregnant female rats were divided into two groups: control group and STZ injection group. The pregnant rats in the STZ injection group were administered 40 mg/kg of STZ intraperitoneally. After birth, the rat pups were divided into the following four groups: control group, control with postnatal exercise group, maternal STZ-injection group, and maternal STZ-injection with postnatal exercise group. The rat pups in the postnatal exercise groups were made to run on a treadmill for 30 min once a day, 5 times per week for 2 weeks beginning 4 weeks after birth. The rat pups born to diabetic rats were shown to have short-term memory impairment with suppressed cell proliferation and increased apoptosis in the hippocampal dentate gyrus. Postnatal treadmill exercise alleviated short-term memory impairment by increased cell proliferation and suppressed apoptosis in the rat pups born to diabetic rats. These findings indicate that postnatal treadmill exercise may be used as a valuable strategy to ameliorate neurodevelopmental problems in children born to diabetics. PMID:25210695

Kim, Young Hoon; Sung, Yun-Hee; Lee, Hee-Hyuk; Ko, Il-Gyu; Kim, Sung-Eun; Shin, Mal-Soon; Kim, Bo-Kyun



Neonatal superior ovarian nerve transection disturbs the cyclic activity of the female rats.  


The neural pathway most related with ovarian steroidogenesis has been identified as the superior ovarian nerve (SON). This work constitutes the first study of the effects of early ovarian SON transection, which was performed in rats of 4 days of age (SON-t rats) to magnify the effects of the denervation. The rats were studied at the prepubertal (30 days), peripubertal (41 days) and adult cyclic in dioestrus (60 days) reproductive stages. The SON-t rats showed a delay of vaginal opening, a notable disruption of oestrous cyclicity, and a large number of corpora lutea. In all the stages, the circulating levels of FSH, prolactin and growth hormone were lower in SON-t rats than in controls, whereas LH did not vary. Serum androstenedione levels were higher in SON-t rats at 30 days and lower at 41 days, compared with control animals while no difference was observed at 60 days. Serum progesterone levels did not differ between control and SON-t, but serum oestradiol concentrations were higher in SON-t rats in all of the stages. At the peripubertal stage, there were fewer ovarian beta-adrenergic receptors in SON-t ovaries, associated with a rise in the ovarian content of norepinephrine, but no changes were observed in SON-t rats at 30 and 60 days with respect to the controls. The release of progesterone in vitro from luteal cell in SON-t rats at 60 days was reduced in basal condition and under ovine LH or FSH stimulation, when compared with control animals; while no difference was observed in presence of isoproterenol or androstenedione in the culture medium. In corpora lutea of SON-t rats at 60 days, no change was observed in the activity of 3beta-hydroxysteroid dehydrogenase (3beta-HSD), but the activity of 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) was reduced, suggesting abnormal luteolysis in spite of the large number of corpora lutea. The interruption of innervation at an early age by SON transection is very important in the regulation of ovarian development in prepubertal and cyclic rats. The functional changes observed in the ovary suggest a possible alteration in the hypothalamic-hypophyseal axis. PMID:12429141

Forneris, Myriam L; Aguado, Luis I



Effect of herbal preparation on heavy metal (cadmium) induced antioxidant system in female Wistar rats.  


Cadmium is one of the elements found to damage antioxidant systems in mammals. To ameliorate cadmium toxicity and to prevent oxidative stress, natural products may be useful. In Indian ethnobotanical practice, a mixture of 17 herbal products is used to fortify the reproductive system of women after parturition and to reverse ovarian oxidative stress. Oral administration of this extract to rats exposed to cadmium was useful in reversing oxidative stress. Two different doses of cadmium (50 ppm and 200 ppm) were given to Wistar rats aged 45 and 65 days. An herbal extract derived from 17 plants was administered orally every day at a dose level of 200 mg/kg of body weight to the rats exposed to cadmium. A battery of enzymes involved in antioxidant activity in the ovary, including superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx) and glutathione-s-transferase (GST) were measured in the control, cadmium-exposed rats without treatment and in the cadmium-exposed rats treated with herbal extract. The reduction in SOD, catalase, GPx and GST activity after cadmium exposure improved significantly in the rats treated with the herbal extract (p?

Dailiah Roopha, P; Padmalatha, C



Stress Hormone and Reproductive System in Response to Honey Supplementation Combined with Different Jumping Exercise Intensities in Female Rats  

PubMed Central

This study was performed to determine the effects of 8-week honey supplementation combined with different jumping exercise intensities on serum cortisol, progesterone, estradiol, and reproductive organs. Eighty-four 9-week-old female rats were divided into 7 groups: baseline controls (C0), sedentary group (C), 20 and 80 jumps per day (Ex20J, Ex80J), honey (H), and combined honey with 20 and 80 jumps per day (HEx20J, HEx80J) groups. Jumping exercise was performed at 5 days/week and honey was given at a dosage of 1?g/kg body weight/day for 7 days/week. The level of serum cortisol was higher in Ex20J and Ex80J compared to C. There was significantly lower value of serum cortisol in HEx20J compared to Ex80J. Serum progesterone levels were significantly lower in Ex20J and Ex80J compared to C. However, serum progesterone levels were significantly higher in HEx20J and HEx80J compared to Ex20J and Ex80J. Relative uterine weights were significantly greater in HEx20J compared to C and HEx80J, respectively. There was no significant difference in estradiol level and relative ovarian weights among all the groups. Therefore, honey elicited beneficial effects in reducing the increase of cortisol and in increasing the reduce of progesterone levels induced by different intensities jumping exercise in female rats. PMID:24672778



Effects of perinatal methylphenidate (MPH) treatment on postweaning behaviors of male and female Sprague-Dawley rats.  


Methylphenidate (MPH) is a common treatment for adult Attention Deficit Hyperactivity Disorder (ADHD). However, little information exists regarding its safety during pregnancy and thus, women with ADHD face difficult decisions regarding continued use during pregnancy. Thus, Sprague-Dawley rats were orally treated 3×/day with 0 (control), 6 (low), 18 (mid), or 42 (high) mg MPH/kg/day (i.e., 0, 2, 6, or 14mg/kg at each treatment time) on gestational days 6-21. All offspring/litter were orally treated with the same dose their dam had received on postnatal days (PNDs) 1-21. After weaning, offspring were assessed for adolescent play behavior, locomotor activity, motor coordination, Barnes maze performance, acoustic startle response, novel object recognition, residential running wheel activity, flavored solution intake, home cage behavior, water maze performance, elevated plus maze behavior, locomotor response to an MPH challenge, and passive avoidance. At euthanasia, whole brain and striatal weights as well as serum hormone levels were measured. Body weights of the high MPH group were reduced in both sexes. Males of the high MPH group were less active than control males in open field assessments on PNDs 40-42. Latency to maximum acoustic startle was significantly altered in females of the medium and high MPH groups and residential running wheel activity of females of the low and medium MPH groups was lower than control females. Open arm entries in the elevated plus maze were increased in subjects of the medium MPH group. Females of the low MPH group were less sensitive to the locomotor-increasing effects of an acute 5mg/kg MPH challenge. Serum hormone levels and whole brain and striatal weights were not altered by prior MPH treatment. These results indicate that MPH treatment during development has sporadic effects on postweaning behaviors and those effects were generally exhibited by females. PMID:25514582

Ferguson, Sherry A; Delbert Law, C; Sahin, Leyla; Montenegro, Susan V



Inhibition and recovery of maternal and fetal cholinesterase enzyme activity following a single cutaneous dose of methyl parathion and diazinon, alone and in combination, in pregnant rats.  


Pregnant Sprague-Dawley rats (14-18 days of gestation) were treated with a single cutaneous subclinical dose(s) of 10 mg kg(-1) (15% of LD(50)) of methyl parathion (O,O-dimethyl O-4-nitrophenyl phosphorothioate) and 65 mg kg(-1) (15% of LD(50)) of diazinon (O,O)-diethyl O-2-isopropyl-6-methylpyrimidinyl phosphorothioate, and their combination. Animals were sacrificed at 1, 2, 4, 12, 24, 48, 72, and 96 h after dosing. Inhibition of maternal and fetal cholinesterase enzyme activity has been determined. Methyl parathion significantly inhibited maternal and fetal brain acetylcholinesterase (AChE) and plasma butyrylcholinesterase (BuChE) activity within 24 h after dosing. Diazinon and a mixture of methyl parathion and diazinon caused lesser inhibition compared with methyl parathion alone. Recovery of maternal and fetal brain AChE activity was in the order of diazinon > combination of diazinon and methyl parathion > methyl parathion 96 h after dosing. Although fetal plasma BuChE activity recovered to 100% of control within 96 h of application, maternal BuChE activity remained inhibited to 55% and 32% of control 96 h after application of methyl parathion and a mixture of methyl parathion and diazinon, respectively. Following a single dermal dose of methyl parathion, the activity of maternal liver BuChE was 63% of control 2 h after dosing, whereas inhibition of placental AChE or BuChE activity occurred 12 and 1 h following a single dose of methyl parathion, corresponding to activities of 63% and 54% of control, respectively. Diazinon, alone or in combination with methyl parathion, did not inhibit significantly the maternal liver BuChE or placental AChE and BuChE activity. The results suggest that dermal application of a single dose of methyl parathion and diazinon, alone or in combination, has an easy access into maternal and fetal tissues, resulting in inhibition of cholinesterase enzymes. The lower inhibitory effect of the combination of methyl parathion and diazinon might be due to competition of diazinon with methyl parathion for cytochrome P-450 enzymes, resulting in formation of the potent cholinesterase inhibitor methyl paraoxon. The faster recovery of fetal cholinesterase enzymes is attributed to the rapid de novo synthesis of cholinesterase fetal tissues compared with the mother. PMID:11481665

Abu-Qare, A W; Abou-Donia, M B



Stress differentially alters mu opioid receptor density and trafficking in parvalbumin-containing interneurons in the female and male rat hippocampus  

PubMed Central

Stress differentially affects hippocampal dependent learning relevant to addiction and morphology in male and female rats. Mu opioid receptors (MORs), which are located in parvalbumin (PARV)-containing GABAergic interneurons and are trafficked in response to changes in the hormonal environment, play a critical role in promoting principal cell excitability and long-term potentiation. Here, we compared the effects of acute and chronic immobilization stress (AIS and CIS) on MOR trafficking in PARV-containing neurons in the hilus of the dentate gyrus in female and male rats using dual label immuno-electron microscopy. Following AIS, the density of MOR silver-intensified gold particles (SIGs) in the cytoplasm of PARV-labeled dendrites was significantly reduced in females (estrus stage). Conversely, AIS significantly increased the proportion of cytoplasmic MOR SIGs in PARV-labeled dendrites in male rats. CIS significantly reduced the number of PARV-labeled neurons in the dentate hilus of males but not females. However, MOR/PARV-labeled dendrites and terminals were significantly smaller in CIS females, but not males, compared to controls. Following CIS, the density of cytoplasmic MOR SIGs increased in PARV-labeled dendrites and terminals in females. Moreover, the proportion of near-plasmalemmal MOR SIGs relative to total decreased in large PARV-labeled dendrites in females. After CIS, no changes in the density or trafficking of MOR SIGs were seen in PARV-labeled dendrites or terminals in males. These data show that AIS and CIS differentially affect available MOR pools in PARV-containing interneurons in female and male rats. Furthermore, they suggest that CIS could affect principal cell excitability in a manner that maintains learning processes in females but not males. PMID:23720407

Milner, Teresa A.; Burstein, Suzanne R.; Marrone, Gina F.; Khalid, Sana; Gonzalez, Andreina D.; Williams, Tanya J.; Schierberl, Kathryn C.; Torres-Reveron, Annelyn; Gonzales, Keith L.; McEwen, Bruce S.; Waters, Elizabeth M.



The effect of chemically induced colitis, psychological stress and their combination on visceral pain in female Wistar rats.  


Visceral sensitivity is of pathophysiological importance in abdominal pain disorders and can be modulated by inflammation and stress. However, it is unclear whether inflammation and stress alter visceral perception independently of each other or in conjunction through neuroendocrine interactions. Therefore, we compared the short- and long-term effects of experimental colitis and water avoidance stress (WAS), alone or in combination, on visceral sensitivity in female Wistar rats. Colitis was induced by trinitrobenzene sulfonic acid (TNBS) and colonoscopically confirmed. During WAS, rats were placed on a platform surrounded by water for 1?h. Visceral sensitivity was assessed by quantifying the visceromotor responses (VMRs) to colorectal distension. Activation of the hypothalamic-pituitary-adrenal axis was determined by measuring serum corticosterone in a separate protocol. TNBS instillation resulted in overt colitis, associated with significant visceral hypersensitivity during the acute inflammatory phase (3 days post-TNBS; n?=?8/group); after colitis had subsided (28 days post-TNBS), hypersensitivity was resolved (n?=?4-8/group). Single WAS was associated with increased VMRs of a magnitude comparable to acute TNBS-induced hypersensitivity (n?=?8/group). However, after repetitive WAS no significant hypersensitivity was present (n?=?8/group). No additive effect of colitis and stress was seen on visceral pain perception (n?=?6-8/group). Corticosterone levels were only increased in acute TNBS-colitis, acute WAS and their combination. To conclude, both colitis and stress successfully induced short-term visceral hypersensitivity and activated the hypothalamic-pituitary-adrenal axis, but long-term effects were absent. In addition, our current findings do not support an additive effect of colitis and stress on visceral sensitivity in female Wistar rats. PMID:25089934

Deiteren, Annemie; Vermeulen, Wim; Moreels, Tom G; Pelckmans, Paul A; De Man, Joris G; De Winter, Benedicte Y



Modulation of imidazoline I2 binding sites by CR4056 relieves postoperative hyperalgesia in male and female rats  

PubMed Central

BACKGROUND AND PURPOSE CR4056 is a novel imidazoline-2 (I2) ligand exhibiting potent analgesic activity in animal models of pain. In this study, we investigated the effects of CR4056 in a well-established model of postoperative pain where rats develop hyperalgesia in the injured hind paw. EXPERIMENTAL APPROACH By measuring paw withdrawal threshold to mechanical pressure, we studied the pharmacology of CR4056, potential sex differences in pain perception and response to treatment, and the pharmacodynamic interaction of CR4056 with morphine. KEY RESULTS Oral CR4056 and subcutaneous morphine dose-dependently reversed the hyperalgesic response. Analgesic effects of CR4056 were completely suppressed by the non-selective imidazoline I2/?2-adrenoceptor antagonist idazoxan, were partially reduced (?30%; P < 0.05) by the selective ?2-adrenoceptor antagonist yohimbine, but were not influenced by the non-selective I1/?2-adrenoceptor antagonist efaroxan or by the ? opioid receptor antagonist naloxone. We found no differences in responses to CR4056 or morphine between male and female rats. However, females had a lower pain threshold than males, and needed lower doses of drugs to reach a significant analgesia. When CR4056 and morphine were combined, their median effective doses were lower than expected for additive effects, both in males and in females. Isobolographic analysis confirmed a synergism between CR4056 and morphine. CONCLUSIONS AND IMPLICATIONS CR4056 is a novel pharmacological agent under development for postoperative pain both as stand-alone treatment and in association with morphine. CR4056 has successfully completed Phase I studies for tolerability and pharmacokinetics in healthy volunteers, and is currently entering the first proof-of-concept study in patients. PMID:24758515

Lanza, Marco; Ferrari, Flora; Menghetti, Ilaria; Tremolada, Dario; Caselli, Gianfranco



Prenatal ethanol exposure programs an increased susceptibility of non-alcoholic fatty liver disease in female adult offspring rats.  


Prenatal ethanol exposure (PEE) induces dyslipidemia and hyperglycemia in fetus and adult offspring. However, whether PEE increases the susceptibility to non-alcoholic fatty liver disease (NAFLD) in offspring and its underlying mechanism remain unknown. This study aimed to demonstrate an increased susceptibility to high-fat diet (HFD)-induced NAFLD and its intrauterine programming mechanisms in female rat offspring with PEE. Rat model of intrauterine growth retardation (IUGR) was established by PEE, the female fetus and adult offspring that fed normal diet (ND) or HFD were sacrificed. The results showed that, in PEE+ND group, serum corticosterone (CORT) slightly decreased and insulin-like growth factor-1 (IGF-1) and glucose increased with partial catch-up growth; In PEE+HFD group, serum CORT decreased, while serum IGF-1, glucose and triglyceride (TG) increased, with notable catch-up growth, higher metabolic status and NAFLD formation. Enhanced liver expression of the IGF-1 pathway, gluconeogenesis, and lipid synthesis as well as reduced expression of lipid output were accompanied in PEE+HFD group. In PEE fetus, serum CORT increased while IGF-1 decreased, with low body weight, hyperglycemia, and hepatocyte ultrastructural changes. Hepatic IGF-1 expression as well as lipid output was down-regulated, while lipid synthesis significantly increased. Based on these findings, we propose a "two-programming" hypothesis for an increased susceptibility to HFD-induced NAFLD in female offspring of PEE. That is, the intrauterine programming of liver glucose and lipid metabolic function is "the first programming", and postnatal adaptive catch-up growth triggered by intrauterine programming of GC-IGF1 axis acts as "the second programming". PMID:24275070

Shen, Lang; Liu, Zhongfen; Gong, Jun; Zhang, Li; Wang, Linlong; Magdalou, Jacques; Chen, Liaobin; Wang, Hui



Heat exposure in female rats elicits abnormal fear expression and cellular changes in prefrontal cortex and hippocampus.  


Despite a twofold higher prevalence of fear-related disorders in women, the neurobiological factors that modulate and drive fear expression are rarely studied in female animals. Fear conditioning and extinction are useful tools for dissecting these mechanisms, and here we tested the effects of environmental manipulations - four days of exposure to 31°C temperatures in the animal housing facility - on fear learning and memory exclusively in female rats. We found that heat exposure disrupted freezing to tone during fear conditioning, and elicited enhanced freezing during extinction and extinction retrieval. We also performed immunohistochemistry for c-fos expression in the infralimbic (IL) and prelimbic (PL) regions of the prefrontal cortex during extinction retrieval, and found that heat exposure induced a switch from IL-dominated activity to PL-dominated activity. Finally, morphological analysis of spines in hippocampal CA3 neurons revealed an increase in spine head diameter in heat-exposed animals, which may partly underlie the persistent freezing observed in these animals. Together, our data show that heat exposure can induce changes at behavioral, physiological, and structural levels, and add to a woefully lacking body of literature on fear processes in female animals. PMID:24859751

Gruene, Tina M; Lipps, Jennifer; Rey, Colin D; Bouck, Anna; Shansky, Rebecca M



Na+K+-ATPase Activity and K+ Channels Differently Contribute to Vascular Relaxation in Male and Female Rats  

PubMed Central

Gender associated differences in vascular reactivity regulation might contribute to the low incidence of cardiovascular disease in women. Cardiovascular protection is suggested to depend on female sex hormones’ effects on endothelial function and vascular tone regulation. We tested the hypothesis that potassium (K+) channels and Na+K+-ATPase may be involved in the gender-based vascular reactivity differences. Aortic rings from female and male rats were used to examine the involvement of K+ channels and Na+K+-ATPase in vascular reactivity. Acetylcholine (ACh)-induced relaxation was analyzed in the presence of L-NAME (100 µM) and the following K+ channels blockers: tetraethylammonium (TEA, 2 mM), 4-aminopyridine (4-AP, 5 mM), iberiotoxin (IbTX, 30 nM), apamin (0.5 µM) and charybdotoxin (ChTX, 0.1 µM). The ACh-induced relaxation sensitivity was greater in the female group. After incubation with 4-AP the ACh-dependent relaxation was reduced in both groups. However, the dAUC was greater in males, suggesting that the voltage-dependent K+ channel (Kv) participates more in males. Inhibition of the three types of Ca2+-activated K+ channels induced a greater reduction in Rmax in females than in males. The functional activity of the Na+K+-ATPase was evaluated by KCl-induced relaxation after L-NAME and OUAincubation. OUA reduced K+-induced relaxation in female and male groups, however, it was greater in males, suggesting a greater Na+K+-ATPase functional activity. L-NAME reduced K+-induced relaxation only in the female group, suggesting that nitric oxide (NO) participates more in their functional Na+K+-ATPase activity. These results suggest that the K+ channels involved in the gender-based vascular relaxation differences are the large conductance Ca2+-activated K+ channels (BKCa) in females and Kv in males and in the K+-induced relaxation and the Na+K+-ATPase vascular functional activity is greater in males. PMID:25187951

Dias, Fernanda Moura Vargas; Ribeiro Júnior, Rogério Faustino; Fernandes, Aurélia Araújo; Fiorim, Jonaina; Travaglia, Teresa Cristina Francischetto; Vassallo, Dalton Valentim; Stefanon, Ivanita



Effects of developmental exposure to mixtures of environmental contaminants on the hepatic metabolism of estradiol-17? in immature female Sprague Dawley rats.  


Exposure to environmental contaminants induces the activation of cytochrome P450s (CYP) which lead to the hydroxylation of contaminants and endogenous hormones such as estrogens. The hydroxylation of estrogens forms catecholestrogens (CEs), one of them being the mutagenic 4-hydroxyestradiol-17? (4-OH-E2). Catecholestrogens are transformed by catechol-o-methyltransferases (COMTs) into nonreactive methoxyestrogens. To investigate the hepatic metabolism of estradiol-17? in female offspring at postnatal day (PND) 21, pregnant rats were dosed daily from gestation day 1 until PND 21 with 2 dose levels of organochlorine pesticides (OCPs; 0.019 or 1.9 mg/kg per d), methylmercury (MeHg; 0.02 or 2 mg/kg per d), polychlorinated biphenyls (PCBs; 0.011 or 1.1 mg/kg per d), or a mixture (M; 0.05 or 5 mg/kg per d) including all 3 groups of chemicals. Concentrations of organochlorines in the mixture M were based on their proportions in serum of the Canadian Arctic population. The messenger RNA (mRNA) expressions of CYP and COMT were analyzed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). High-performance thin layer chromatography and phosphor imaging were used to measure the transformation of (14)C substrates into estrogen metabolites. The low-dose treatments or the MeHg groups had no effect. The high-dose OCP, PCB, and M group increased the production of 2-OH-E2 and 6?-OH-E2, while only the PCB and M groups increased the 2-OH-CE/methoxyestrogen ratio. In all groups, the cytosolic COMT activity exceeded the microsomal production rate of 4-OH-E2. Although the M treatment included the PCB and OCP mixtures, it did not modify the estrogen metabolism more than did the PCB mixture alone. This endocrine disruption information contributes to our understanding of chemical interactions in the toxicology of chemical mixtures. PMID:22914890

Desaulniers, Daniel; Leingartner, K; Pelletier, G; Xiao, G-H; Bowers, W J



Effect of prenatal methamphetamine exposure and challenge dose of the same drug in adulthood on epileptiform activity induced by electrical stimulation in female rats.  


Our previous study demonstrated that chronic prenatal methamphetamine (MA) exposure and a single dose of MA in adulthood decrease focally induced epileptiform activity in adult male rats. As seizures are known to be dependent on sex and female estrous cycle, the goal of the present study was to examine the combined effect of prenatal MA exposure (5mg/kg) and the MA challenge dose (1mg/kg) in adulthood on electroencephalography (EEG) recordings and consequences of brain stimulation in freely moving adult female rats with respect to the estrous cycle. Overall, 12 groups of adult female rats were tested: prenatally MA-exposed, prenatally saline-exposed and rats without prenatal injections, each of these groups was either postnatally challenged with MA or with saline injection (MA-MA, MA-S; S-MA, S-S; C-MA, C-S) and further divided according to the stage of the estrous cycle to metestrus/diestrus (M/D) or proestrus/estrus (P/E). Seizures were induced by repetitive electrical stimulation (15s/8Hz) of sensorimotor cortex. Stimulation threshold, duration of afterdischarges (ADs), and presence and duration of spontaneous ADs (SADs) were evaluated. Additionally, behavior associated with stimulation and ADs, and occurrence of wet-dog-shakes (WDS) were analyzed. The present study demonstrates that the prenatal MA exposure decreased the seizure threshold in females in M/D, but not in females in P/E. In addition, prenatally MA-exposed M/D females injected with saline in adulthood had increased the duration of ADs as well as SADs. The challenge dose of MA also decreased the seizure threshold. Moreover, prenatal as well as adult MA administration decreased the number and occurrence of WDS, respectively. Thus, the present study demonstrates that the effect of prenatal MA exposure and challenge dose of the same drug on focally induced epileptiform activity in adult female rats depends on the estrous cycle. PMID:24215975

Mat?jovská, I; Bernášková, K; Šlamberová, R



Effect of supernatant from fibroblasts from the progeny of female rats with chronic liver disease of different origin on the morphology and function of cultured peritoneal macrophages.  


We studied the effects of supernatant from ovarian fibroblasts derived from the progeny of female rats with experimental chronic liver disease of different genesis on the function of cultured allogenic peritoneal macrophages. Addition of fibroblast supernatant derived from animals with liver disease to the culture medium suppressed the function of peritoneal macrophages from intact newborn rats, which manifested in reduction of the adhesion characteristics and decrease of their phagocytic parameter and phagocytic index. PMID:23486594

Bryukhin, G V; Zubarev, I V



The effect of developmental vitamin D deficiency in male and female Sprague-Dawley rats on decision-making using a rodent gambling task.  


Developmental vitamin D (DVD) deficiency is a plausible risk factor for schizophrenia that has been associated with behavioural alterations including disruptions in latent inhibition and response inhibition. The rodent gambling task (rGT) assesses risk-based decision-making, which is a key cognitive deficit observed in schizophrenia patients. The primary aim of this study was to examine risk-based decision-making in DVD-deficient and control rats on the rGT. We also evaluated the performance of female Sprague-Dawley rats on the rGT for the first time. Adult male and female Sprague-Dawley rats from control and vitamin D deficient dams were trained to perform the rGT in standard operant chambers and their performance and choice-preferences were assessed. Female rats were significantly faster to reach rGT training criteria compared with male rats and DVD-deficient rats were faster to reach training criteria than control animals. After reaching stable performance on the rGT DVD-deficient and control rats showed a significant preference for the optimal choice-option in the rGT, but there were no significant effects of sex or diet on these responses. DVD deficiency did not alter the decision-making processes on the rGT because no significant changes in choice-preferences were evident. This is the first study to demonstrate that once established, the performance of females is comparable to male Sprague-Dawley rats on the rGT. PMID:25447469

Peak, J N; Turner, K M; Burne, T H J



Acute and transient effects of stress on immunoreactive somatostatin cell bodies and fibers in the preoptic-anterior hypothalamus and median eminence of female rats  

Microsoft Academic Search

Stress in rats causes acute release of hypothalamic somatostatin (SS) in median eminence (ME) that induces a marked and prolonged\\u000a suppression of growth hormone (GH) secretion. This was evidenced by immunocytochemistry (ICC) and radioimmunoassay (RIA) in\\u000a the present study. Adult female rats were decapitated under nonstress or for 30, 60, 120 and 180 min after 15 min leg restraint\\u000a stress.

Maheep Bhatnagar



Psychophysiology and posttraumatic stress disorder symptom profile in pregnant African-American women with trauma exposure.  


While female sex is a robust risk factor for posttraumatic stress disorder (PTSD), pregnant women are an understudied population in regards to PTSD symptom expression profiles. Because circulating hormones during pregnancy affect emotionality, we assessed whether pregnant women would have increased expression of the intermediate phenotypes of hyperarousal and fear-potentiated startle (FPS) compared to non-pregnant women. We examined PTSD symptom profiles in pregnant (n?=?207) and non-pregnant women (n?=?370). In a second study, FPS responses were assessed in 15 pregnant and 24 non-pregnant women. All participants were recruited from the obstetrics and gynecology clinic at a public hospital serving a primarily African-American, low socioeconomic status, inner-city population. Our results indicate that overall PTSD symptoms were not different between the groups of women. However, pregnant women reported being more hypervigilant (p?=?0.036) than non-pregnant women. In addition, pregnant women showed increased FPS to a safety signal compared to non-pregnant women (p?=?0.024). FPS to a safety signal in pregnant women was significantly correlated with PTSD hyperarousal symptoms (r?=?0.731, p?pregnant women (p?=?0.008), but not in pregnant women (p?=?0.895). Together, these data suggest that pregnant women show clinical and psychophysiological hyperarousal compared to non-pregnant women, and support screening for PTSD and assessment of PTSD risk in pregnant women. PMID:25278341

Michopoulos, Vasiliki; Rothbaum, Alex O; Corwin, Elizabeth; Bradley, Bekh; Ressler, Kerry J; Jovanovic, Tanja



Comparison between two experimental protocols to promote osteoporosis in the maxilla and proximal tibia of female rats.  


The effects of two experimental protocols (ovariectomy associated or not with a low calcium diet) used to promote osteoporosis in the rat maxilla and proximal tibia were compared 5 and 11 weeks after surgery. Female Wistar rats were ovariectomized or sham-operated. Half of the ovariectomized rats were fed a low Ca++ diet (ovx*) and the remaining ovariectomized (ovx) and sham animals received a standard chow. At sacrifice, the proximal metaphysis was excised from the tibia and the molars were extracted from the hemi-maxilla. Dry (60 degrees C overnight) and ash (700 degrees C/14 h) weights were measured and the ashes were used for Ca++ measurement by means of a colorimetric method. After 5 weeks, ovx caused no alteration while ovx* decreased proximal metaphysis (17%) and maxilla (35%) bone mass. After 11 weeks, ovx caused a 14% bone mass reduction in the proximal metaphysis but not in the maxilla, while ovx* caused a comparable bone mass reduction (30%) in both bone segments. Calcium concentration was not altered in any experimental condition. The results show that estrogen deficiency is insufficient to cause maxillary osteoporosis in rats over an 11-week period and a long-term ovariectomy is needed to exert deleterious effect on proximal metaphysis bone mass. When a low Ca++ diet is associated with estrogen deficiency, however, a relatively precocious harmful effect is observed, twice as pronounced in the maxilla than in the proximal metaphysis. On a long-term basis, ovariectomy associated with a low Ca++ diet seems to be equally injurious to both proximal metaphysis and maxilla. PMID:15107910

Teófilo, Juliana Mazzonetto; Azevedo, Ana Carolina Bernardes; Petenusci, Sérgio Olavo; Mazaro, Renata; Lamano-Carvalho, Teresa Lúcia



Dietary agent indole-3-carbinol protects female rats against the hepatotoxicity of the antitumor drug ET-743 (trabectidin) without compromising efficacy in a rat mammary carcinoma.  


ET-743, an experimental antitumor drug with promising activity in sarcoma, breast and ovarian carcinoma, is currently under phase 2 clinical evaluation. It is hepatotoxic in animals and patients. We tested the hypothesis that indole-3-carbinol (I3C), the hydrolysis product of glucosinolates occurring in cruciferous vegetables, may protect against ET-743-induced hepatotoxicity in the female Wistar rat, the animal species with the highest sensitivity toward the adverse hepatic effect of this drug. Hepatotoxicity was adjudged by measurement of plasma levels of bilirubin, alkaline phosphatase (ALP) and aspartate aminotransferase (AST) and by liver histopathology. The effect of I3C on the kinetics of ET-743 in rat plasma and liver was investigated by high-pressure liquid chromatography. The effect of I3C on the antitumor efficacy of ET-743 was explored in rats bearing the 13762 mammary carcinoma. ET-743 (40 microg/kg i.v.) alone caused an elevation of plasma bilirubin, ALP and AST levels and degeneration and patchy focal necrosis of bile duct epithelial cells. Addition of I3C to the diet (0.5%) for 6 days prior to ET-743 administration almost completely abolished manifestations of hepatotoxicity. In contrast, a dietary concentration of 0.1% I3C did not protect, nor did dietary diindolylmethane (0.2%), an acid-catalyzed condensation product of I3C. Ingestion by rats of I3C for 6 days prior to ET-743 (40 microg/kg i.v.) decreased plasma but not hepatic concentrations of ET-743 compared to animals that received ET-743 alone. I3C did not interfere with the antitumor efficacy of ET-743. The results suggest that ingestion of I3C may counteract the unwanted effect of ET-743 in the liver. I3C should be investigated as a hepatoprotectant in patients who receive ET-743 therapy. PMID:15300810

Donald, Sarah; Verschoyle, Richard D; Greaves, Peter; Colombo, Tina; Zucchetti, Massimo; Falcioni, Cristiano; Zaffaroni, Marco; D'Incalci, Maurizio; Manson, Margaret M; Jimeno, Jose; Steward, William P; Gescher, Andreas J



Endocrine disruptors differently influence estrogen receptor ? and androgen receptor in male and female rat VSMC.  


Sex steroid hormones differently control the major physiological processes in male and female organisms. In particular, their effects on vascular smooth muscle cells (VSMCs) migration are at the root of sex/gender-related differences reported in the cardiovascular system. Several exogenous substances, defined endocrine disruptor chemicals (EDCs),