Note: This page contains sample records for the topic pregnant female rats from
While these samples are representative of the content of,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of
to obtain the most current and comprehensive results.
Last update: November 12, 2013.

Does dihydrotestosterone induce atresia in the hypophysectomized immature female rat treated with pregnant mare's serum gonadotropin?  


This study was originally designed to test the hypothesis that the binding of luteinizing hormone in granulosa cells decreases with atresia. The hypophysectomized immature female rat that was primed with pregnant mare's serum gonadotropin and treated with dihydrotestosterone was used as a model for atresia. Histochemical analysis of acid phosphatase was used as a marker for atresia and topical autoradiography with iodine 125-labeled human chorionic gonadotropin for binding of luteinizing hormone. Histologically, there was no significant difference in atresia, acid phosphatase, or 125I-labeled human chorionic gonadotropin binding in antral follicles between control animals given pregnant mare's serum gonadotropin and animals treated with pregnant mare's serum gonadotropin and dihydrotestosterone. Assessment of the total follicular population, however, showed that dihydrotestosterone at dosages of 1 and 5 mg/kg resulted in decreases in atresia of 48% and 58%, respectively. Although these data disprove our hypothesis, they strongly suggest that dihydrotestosterone decreases follicular atresia by increasing the number of small preantral follicles. PMID:3970094

Kohut, J K; Jarrell, J F; YoungLai, E V



Effects of oral androstenedione on steroid metabolism in liver of pregnant and non-pregnant female rats  

Microsoft Academic Search

It is unknown whether androstenedione, a steroidal dietary supplement taken to enhance athletic performance, can affect physiological hormone levels by altering liver enzyme activities that metabolize steroid hormones. Altered hormone levels could be especially devastating during pregnancy. Mature female rats were gavaged with 0, 5, 30 or 60mg\\/kg\\/day androstenedione beginning two weeks prior to mating and continuing through gestation day

T. J. Flynn; P. P. Sapienza; P. W. Wiesenfeld; I. A. Ross; S. Sahu; C. S. Kim; M. W. O’Donnell; T. F. X. Collins; R. L. Sprando



Red blood cell glutathione peroxidase activity in female nulligravid and pregnant rats  

PubMed Central

Background The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise. Methods Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes. Results The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity. Conclusion The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy.

Gallo, Giuseppe; Martino, Guglielmo



The impact of unabated stimulation by human chorionic gonadotropin on the steroid hormone environment of pregnant rats and the spontaneous expression of ovarian cysts in female progeny  

Microsoft Academic Search

Unabated stimulation by low doses of human chorionic gonadotropin (hCG) induces ovarian cysts in pregnant rats. In order to\\u000a determine the impact of these in vivo treatments on the hormonal milieu of pregnancy, and the potential impact of an aberrant\\u000a cystic-ovary state during pregnancy on the resulting female offspring, pregnant rats were treated with either 0 (control),\\u000a 1, or 3 IU

Katryna Bogovich



Vitamin A supplementation to pregnant and breastfeeding female rats induces oxidative stress in the neonatal lung.  


Vitamin A is an essential micronutrient that regulates many biological processes through modulation of retinoic acid receptor-responsive genes. Vitamin A acts as a systemic antioxidant, participating in the modulation of diverse redox mechanisms involved in physiological and pathological processes. Different studies, however, observed that vitamin A and other retinoids may induce pro-oxidant/deleterious actions under certain conditions, leading to impairment of brain and lung function. Here, we studied the effect of vitamin A treatment at oral doses of 100 IU/kg, 200 IU/kg, and 300 IU/kg to female rats (Rattus norvegicus) during pregnancy and lactation on oxidative parameters of lungs from the offspring vitamin A supplementation induced increases in lipoperoxidation, protein carbonyl, activities of the antioxidant enzymes superoxide dismutase and catalase (200 IU/kg, and 300 IU/kg), and decreased sulphydryl protein (500 IU/kg) content in the neonatal lung. PMID:20679000

Pasquali, Matheus Augusto de Bittencourt; Schnorr, Carlos Eduardo; Feistauer, Lucas Brambilla Hilbig; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca



Comparative pharmacokinetics of 14 C-piperacillin following intravenous and intraperitoneal administration in pregnant and non-pregnant rats  

Microsoft Academic Search

Summary  \\u000a 14C-piperacillin (Pipracil®) at a dose level of 1000 mg\\/kg was administered intravenously or intraperitoneally to pregnant and\\u000a non-pregnant female rats. Rats were sacrificed at predetermined time intervals, and14C-piperacillin concentrations determined in serum, amniotic fluid, placenta, and fetus. The piperacillin serum levels in both\\u000a pregnant and nonpregnant rats following intravenous administration were comparable; however, following intraperitoneal administration,\\u000a the serum drug

V. Batra; J. Morrison; E. Kaleita



Hepatotoxicity of androstenedione in pregnant rats  

Microsoft Academic Search

Androstenedione, a naturally occurring steroid hormone, is a dietary supplement used to enhance athletic performance. Little is known, however, about the safety of its use by young adults including women of child bearing age. To test the possible hepatotoxic effects of androstenedione use, this study was undertaken using a rat model. Pregnant rats (six rats\\/dose) were exposed to androstenedione in

Saura C. Sahu; Philip P. Sapienza; Robert L. Sprando; Thomas F. X. Collins; Ivan A. Ross; Thomas J. Flynn; Paddy L. Wiesenfeld; Michael W. O’Donnell; Chung S. Kim



Effects of oral androstenedione on phospholipid fatty acids, ATP, caspase-3, prostaglandin E 2 and C-reactive protein in serum and livers of pregnant and non-pregnant female rats  

Microsoft Academic Search

Androstenedione, a steroidal dietary supplement taken to enhance athletic performance, could affect serum and liver lipid metabolism, induce liver toxicity or alter inflammatory response depending on dose and duration of exposure. Pregnancy could further exaggerate these effects. To examine this, mature female rats were gavaged with 0, 5, 30 or 60mg\\/kg\\/day androstenedione beginning two weeks prior to mating and continuing

P. W. Wiesenfeld; P. P. Sapienza; T. J. Flynn; C. E. Ford; I. A. Ross; S. Sahu; C. S. Kim; M. W. O’Donnell; T. F. X. Collins; R. L. Sprando



Transplacental transmission of Toxoplasma gondii in reinfected pregnant female canines  

Microsoft Academic Search

Twelve pregnant female canines, naturally infected with Toxoplasma gondii, were reinfected with T. gondii: three (GI) received tachyzoites subcutaneously (1.0?×?107), three (GII) were orally inoculated with oocysts (1.5?×?104),\\u000a and six (GIII) were kept as a nonreinfected control group. All the reinfected female canines (GI and GII) miscarried or presented\\u000a fetal death, while only one GIII female presented a stillborn in

K. D. S. Bresciani; A. J. Costa; G. H. Toniollo; M. C. R. Luvizzoto; C. T. Kanamura; F. R. Moraes; S. H. V. Perri; S. M. Gennari



Impact of Obesity on Fetomaternal Outcome in Pregnant Saudi Females  

PubMed Central

Background: Obesity is rapidly increasing in most populations of the world including Saudi community. Maternal obesity adversely impacts pregnancy outcome through increased rates of hypertensive disease, diabetes, cesarean section and infections. Objectives: The aim of this study is to determine frequency of obesity and its adverse effects on reproductive outcome in pregnant Saudi females. Methods: Prospective Cohort study. Eight months (Nov 2008 to June 2009), Maternity and Children Hospital (MCH) Buraida, Saudi Arabia Sample included a group of 1000 randomly recruited pregnant Saudi females. Patients were admitted through Outpatient and Emergency Departments. Height was recorded once and weight twice; at the beginning (prepregnancy weight) and end of pregnancy. The difference between the two weights was taken as net weight gain in pregnancy. Prepregnancy weight was used to calculate Body mass index (BMI) using formula; Weight in Kg/Height in (m). 2 The sample was divided into 5 groups depending upon their BMI ;< 18.5, 18.5–24.9, 25–29.9, 30–39.9 &>40, classified as underweight, normal weight, overweight, obese & morbidly obese respectively. The normal weight group was used as control group. Data were collected regarding complications of obesity in pregnancy and labor and recorded on a Performa. Results were calculated by using computer programme SPSS Version 13 for windows. A p-value of< 0.05 is used to calculate statistical significance. Results: The frequency of weight distribution in pregnant Saudi female calculated to be 2% (lean), 31% (normal weight), 33%(overweight), 30%(obese) and 4%(morbidly obese). Compared with normal weight women, both overweight and obese women had a significantly increased risk (p-value-<0.05) for gestational diabetes, preeclampsia, cesarean delivery, and delivery of a macrocosmic infant. Conclusion: Overweight & obesity is a growing problem in pregnant Saudi females associated with increased risks of fetomaternal complications like preeclampsia, gestational diabetes, cesarean delivery, and delivery of a macrocosmic infant.

Meher-un-nisa; Aslam, Muhammad; Ahmed, Salah Rosdy; Rajab, Maamon; Kattea, Lina



Femoral bone mineral density and bone mineral content in bromocriptine-treated pregnant and lactating rats  

Microsoft Academic Search

Since hyperprolactinemia was found to induce osteopenia in the metaphysis of long bone in non-mated female rats, pregnant\\u000a and lactating rats with sustainedly high plasma prolactin (PRL) levels might also exhibit some changes in their long bones.\\u000a We performed a longitudinal study in pregnant, lactating and post-weaning rats, using dual-energy X-ray absorptiometry to\\u000a demonstrate site-specific changes (i.e., metaphysis vs. diaphysis)

Panan Suntornsaratoon; Kannikar Wongdee; Nateetip Krishnamra; Narattaphol Charoenphandhu



Reproductive sequelae in female rats after in utero and neonatal exposure to the phytoestrogen genistein  

Microsoft Academic Search

Objective: To determine reproductive sequelae in female rats after in utero and lactational dietary exposure to genistein.Design: Experimental animal study.Setting: University laboratory.Animal(s): Sprague Dawley rats.Intervention(s): Pregnant rats were fed control rat chow or rat chow incorporated with genistein (approximately 50 ?g\\/d) beginning on day 17 of gestation and continuing until the end of lactation (postpartum day 21). Genistein-exposed female pups

Caleb A Awoniyi; Dawn Roberts; D. N. Rao Veeramachaneni; Bradley S Hurst; Kathleen E Tucker; William D Schlaff



Carbon tetrachloride-induced hepatotoxicity in pregnant and lactating rats.  


Carbon tetrachloride (CCl4) is well known to induce hepatotoxicity after being metabolized to trichloromethyl free radical ((.)CCl3) by CYP2E1. In the present study, the hepatotoxicity induced by a single oral dose (2,000 mg/kg) of CCl4 was compared between pregnant (gestation days (GD) 13 and 19) or postpartum (postpartum days (PPD) 1, 13 and 27) and non-pregnant rats. Hepatotoxicity in CCl4-treated pregnant rats evaluated by blood chemistry (alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) activities) and histopathological finding (area of damaged hepatocytes) was minimal on GD19, being weaker than that in non-pregnant rats. CYP2E1 expression in non-treated pregnant rats decreased as pregnancy progressed and reached minimum level on GD19. Thus, the degree of CCl4-induced hepatotoxicity roughly corresponded to CYP2E1 levels during pregnancy. After delivery, hepatotoxicity in CCl4-treated lactating rats was maximal on PPD13, being stronger than that in non-pregnant rats, and then it decreased slightly on PPD27. The CYP2E1 level in the non-treated lactating rats tended to increase but remained at lower levels until PPD13 compared with that in non-pregnant rats. Thus, the degree of CCl4-induced hepatotoxicity did not correspond to CYP2E1 levels during lactation. This suggests that during lactation, there may be certain factors other than CYP2E1 expression responsible for the degree of CCl4-induced hepatotoxicity. PMID:19336974

Mochizuki, Masahiro; Shimizu, Satomi; Urasoko, Yoshinaka; Umeshita, Kazuhiko; Kamata, Takashi; Kitazawa, Takahiro; Nakamura, Daichi; Nishihata, Yoshito; Ohishi, Takumi; Edamoto, Hiroshi



Body Weight and Brown Fat Activity in Hyperphagic Cafeteria-Fed Female Rats and Their Offspring  

Microsoft Academic Search

Presenting pregnant rats with a varied choice of human food items (a cafeteria diet) caused a slight reduction in total protein intake and significant increases in energy intake (32%) and weight gain compared to pregnant females fed stock diet (controls). Cafeteria-fed mothers gave birth to the same number and weight of pups as controls, and these grew normally, but were

Nancy J. Rothwell; Michael J. Stock



In vitro metabolism of cadaverine in the pregnant rat  

Microsoft Academic Search

Thein vitro metabolism of14C-cadaverine by diamine oxidase was investigated in various tissues of pregnant and non-pregnant rats. The metabolites formed were: ?1-piperideine, ?-aminovaleric acid, carbon dioxide and some unidentified compound(s). In most of the tissues investigated ?1-piperideine was the predominant metabolite, but considerable amounts of ?-aminovaleric acid and the unidentified compound(s) were also formed. The oxidative products of cadaverine might

Anne-Charlotte Henningsson; Stig Henningsson



Localization of glycogen in the placenta and fetal and maternal livers of cadmium-exposed diabetic pregnant rats  

Microsoft Academic Search

This study was designed to investigate the effects of Cd exposure on the glycogen localization in the placenta and in fetal\\u000a and maternal livers in streptozotocin (STZ)-induced-diabetic pregnant rats. Ninety-nine virgin female Wistar rats (200–220\\u000a g) were mated with 33 males for at least 12 h. From the onset of pregnancy, the rats were divided into four experimental groups\\u000a (control,

Mecit Yoruk; Mehmet Kanter; Ismail Meral; Zahid Agaoglu



Pregnant rats show enhanced spatial memory, decreased anxiety, and altered levels of monoaminergic neurotransmitters  

Microsoft Academic Search

Spatial memory, anxiety and central monoaminergic activities were measured in non-pregnant (NP) and pregnant females during two time periods of pregnancy: gestational days 7–9 (GD7, GD9) and gestation days 16–18 (GD16, GD18). Pregnant females discriminated between object locations on both test days on an object placement task, whereas NP females were unable to discriminate between locations. Pregnant females displayed decreased

A. H. Macbeth; C. Gautreaux; V. N. Luine




EPA Science Inventory

This study examined whether or not exposure to 4-nonylphenol (NP) during late gestation affects reproductive and mammary development in the offspring of female rats. Time pregnant Long Evans rats were gavaged with NP (10 or 100 mg/kg), atrazine (ATR, 100 mg/kg), or corn oil on ge...


Methamphetamine enhances sexual behavior in female rats  

Microsoft Academic Search

The present study evaluated the effects of methamphetamine (MA) on sexual behavior in female rats. In Experiment 1, ovariectomized, hormone-primed rats were injected with MA (1.0mg\\/kg, i.p.) or saline prior to a test for mate choice wherein females could mate with two males simultaneously. Female rats treated with saline returned to their preferred mate faster after receiving intromissions and visited

Carissa Winland; Charles Haycox; Jessica L. Bolton; Sumith Jampana; Benjamin J. Oakley; Brittany Ford; Laura Ornelas; Alexandra Burbey; Amber Marquette; Russell J. Frohardt; Fay A. Guarraci



The effects of stress on plasma ACTH and corticosterone in young and aging pregnant rats and their fetuses  

SciTech Connect

Compared to younger rats, old rats exhibit prolonged elevations of plasma ACTH and corticosterone (CORT) in response to stress. In addition, CORT crosses the placenta. To investigate whether fetuses of older rats may be exposed to higher concentrations of CORT during development than fetuses of young rats, we compared the effects of stress on hypothalamic-pituitary-adrenal (HPA) axis function in young and aging pregnant rats and their 19-day-old fetuses. The plasma of the mothers and fetuses was assayed for ACTH and CORT by radioimmunoassay. Both young and aging pregnant rats showed a significant increase in plasma ACTH and CORT immediately after exposure to stress. However, aging rats had more prolonged elevation of ACTH and CORT than young rats. This suggests that, like old male rats, aging pregnant rats have an alteration in feedback inhibition of the HPA axis. Prolonged elevation of CORT was also seen in fetuses of aging mothers. These results have important implications concerning the effects of stress during pregnancy at different maternal ages, and for the potential deleterious consequences of prolonged prenatal elevation in stress hormones on the offspring of aging females.

Erisman, S. (William S. Middleton Memorial Veterans Hospital, Madison, WI (USA)); Carnes, M. (William S. Middleton Memorial Veterans Hospital, Madison, WI (USA) Univ. of Wisconsin, Madison (USA)); Takahashi, L.K.; Lent, S.J. (Univ. of Wisconsin, Madison (USA))



Effect of the chemical form of supranutritional selenium on selenium load and selenoprotein activities in virgin, pregnant, and lactating rats.  


Virgin, pregnant, and lactating rats were used to assess the influence of selenomethionine and selenocystine, fed at four to seven times the daily Se requirement (supranutritional), on Se load and selenoprotein activities. Female Sprague Dawley rats (n = 48; age = 13 wk), reared on a low-Se torula yeast diet, were assigned to one of three reproductive states (n = 16 per reproductive state) to occur simultaneously: virgin, pregnant, and lactating. Once reproductive state was achieved, rats were fed (ad libitum) either l-selenomethionine (n = 24) or L-selenocystine (n = 24) diets providing 2.0 microg Se/g of diet (as-fed basis) for 18 d, and then killed. Lactating rats consuming selenomethionine had the greatest Se concentration in the brain, with pregnant rats being intermediate, and virgin rats having the least (P < 0.02). When selenocystine was fed, the concentration of Se in the brain was greater (P = 0.008) in lactating rats, but not different (P = 0.34) between pregnant and virgin rats. Selenium concentrations in the heart, liver, lung, muscle, spleen, plasma, placenta, uterus, and fetus were greatest (P < 0.001) in rats consuming selenomethionine. Brain, kidney, and liver thioredoxin reductase, and brain, erythrocyte, kidney, and liver glutathione peroxidase activities did not differ (P = 0.13 to P = 0.85) between Se treatments. Lactating rats exhibited the greatest (P < 0.006) Se concentration in the heart, lung, muscle, plasma, and spleen compared with pregnant and virgin rats. Thioredoxin reductase was greatest (P < 0.004) in the brain of pregnant rats, greatest (P < 0.004) in the liver of lactating rats, and greater (P < 0.03) in the kidney of lactating and pregnant vs. virgin rats. Regardless of reproductive state, supranutritional Se (2.0 microg/g of diet) fed as selenocystine resulted in less Se load, and when fed as selenomethionine, was equally available for thioredoxin reductase synthesis as the Se in selenocystine. Independent of dietary Se chemical form, thioredoxin reductase activity was responsive to reproductive state. PMID:15644515

Taylor, J B; Finley, J W; Caton, J S



Stress-Induced Proteomic Changes in the Hippocampus of Pregnant Wistar Rats  

PubMed Central

Stress is a threatening factor that all living organisms encounter throughout life. Depending on the type of stress, there are several mechanisms for keeping body homeostasis to minimize stress effects. Brain is an organ which shows high sensitivity to stress conditions. Although many studies have shown induced-stress effects on rat embryos, little is known about the mechanisms involved in coping with stress by female rats during pregnancy. In the present study, restraint stress method was applied because this technique has been widely used in animal models to induce both psychological and physical stress. Restraint stress was applied in regular sessions (1 and 3 hrs) in two groups of 6 pregnant Wistar rats and similar number of animals was used as control group receiving no stress. ACTH and corticosterone levels in plasma samples were shown to increase in response to stress treatments. On the last day of pregnancy, rat hippocampus from the brain of each animal in all three groups was removed and analyzed using 2 Dimensional Gel Electrophoresis (2DE) technique. Using Image Master Software, approximately 2000 proteins were detected in the 2D gels analyzed, among which 34 proteins exhibited differential expression. These results indicate that the proteome patterns from the hippocampus of pregnant rats subjected to 1 and 3 hr of stress differs significantly from the control (unstressed) group. Future mass spectrometry identification of the 34 protein spots discovered in this study should allow a more precise understanding of molecules and cellular pathways involved in stress-induced responses during pregnancy.

Ardekani, Ali M.; Maghsudi, Nader; Meyfour, Anna; Ghasemi, Rasool; Lakpour, Niknam; Nooshinfar, Elahe; Ghaempanah, Zahra



Excretion of Alpha-foetoprotein in the Urine of Pregnant Rats and Hepatoma-bearing animals  

PubMed Central

Urine of normal rats, pregnant animals and animals bearing chemically induced hepatoma was tested with antisera to foetoproteins by the double immunodiffusion technique. Antigens were not detected in the urine of normal rats. Alpha-foetoprotein was demonstrated in the urine of pregnant rats and hepatomabearing animals.

Okon, E.; Rosenmann, E.; Dishon, T.; Boss, J. H.



Methamphetamine enhances sexual behavior in female rats.  


The present study evaluated the effects of methamphetamine (MA) on sexual behavior in female rats. In Experiment 1, ovariectomized, hormone-primed rats were injected with MA (1.0mg/kg, i.p.) or saline prior to a test for mate choice wherein females could mate with two males simultaneously. Female rats treated with saline returned to their preferred mate faster after receiving intromissions and visited their preferred mate at a higher rate than their non-preferred mate. In contrast, MA-treated female rats spent a similar amount of time with their preferred and non-preferred mate and failed to return to their preferred mate faster than to their non-preferred mate following intromissions. Two weeks later, the females received the same drug treatment but were tested for partner preference wherein females could spend time near a male or female stimulus rat. All subjects spent more time near the male stimulus than the female stimulus. However, the MA-treated rats visited the male stimulus more frequently and spent less time near the female stimulus than the saline-treated rats. Similar to Experiment 1, female rats in Experiment 2 were tested for mate choice and then two weeks later tested for partner preference; however, females received three daily injections of MA (1.0mg/kg, i.p.) or saline. Females treated chronically with MA returned to both males faster following intromissions than females treated with saline, independent of preference (i.e., preferred mate and non-preferred mate). Furthermore, MA-treated rats were more likely to leave either male (i.e., preferred or non-preferred mate) than saline-treated rats after receiving sexual stimulation. Although MA-treated subjects spent more time near the male stimulus than the female stimulus, they spent less time near either when compared to saline-treated subjects. The present results demonstrate that MA affects sexual behavior in female rats partly by increasing locomotion and partly by directly affecting sexual behavior. PMID:21396951

Winland, Carissa; Haycox, Charles; Bolton, Jessica L; Jampana, Sumith; Oakley, Benjamin J; Ford, Brittany; Ornelas, Laura; Burbey, Alexandra; Marquette, Amber; Frohardt, Russell J; Guarraci, Fay A



Central Endogenous Opioid Inhibition of Supraoptic Oxytocin Neurons in Pregnant Rats  

Microsoft Academic Search

Naloxone increases oxytocin secretion in pregnant rats, suggesting restraint by endogenous opioicls but we have previously reported that oxytocin nerve terminals in the neural lobe become desensitized to opioid actions in late pregnancy. Therefore, we sought evidence for opioid inhi- bition on oxytocin cell bodies and their inputs at this time. In conscious 21 d pregnant rats naloxone increased the

A. J. Douglas; I. Neumann; H. K. M. Meeren; G. Leng; L. E. Johnstone; G. Munro; J. A. Russell



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...


Cocaine alters dendritic spine density in cortical and subcortical brain regions of the postpartum and virgin female rat.  


Cocaine use during pregnancy induces profound neural and behavioral deficits in both mother and offspring. The present study was designed to compare the effects of cocaine exposure on spine density of postpartum and virgin female rat brains. Timed, pregnant, primiparous rats were injected with either cocaine (30 mg/kg) or saline, once daily, from gestational day 8 to 20. Twenty-four hours after giving birth, dam brains were processed for Golgi-impregnation. Virgin females were also injected with the same dose of cocaine or saline for 12 days and sacrificed 24 h after the last injection for comparison. Pregnant rats had significantly greater spine density in the medial amygdala (MeA) and medial preoptic area (MPOA) and lower spine density in CA1 than virgin females independent of cocaine treatment. Cocaine significantly increased dendritic spine density on the apical branch of pyramidal cells in the prefrontal cortex (PFC, 15%), both apical (13%) and basal (14.8%) branches of CA1 and cells in the MeA (28%) of pregnant rats. In the MPOA, cocaine administration resulted in a decrease in dendritic spine density (14%) in pregnant rats. In virgin females, cocaine had fewer effects but did increase dendritic spine density on both branches of CA1 neurons and in the MeA. The present study is the first to demonstrate that spine density differs between pregnant and virgin females and that pregnancy makes the brain more vulnerable to cocaine, which has important clinical implications. PMID:21480383

Frankfurt, Maya; Salas-Ramirez, Kaliris; Friedman, Eitan; Luine, Victoria



Effects of Perinatal Exposure to Bisphenol A on Brain Neurotransmitters in Female Rat Offspring  

Microsoft Academic Search

Pregnant Sprague-Dawley (CD IGS) rats were orally administered doses of bisphenol A (BPA) at 4, 40, and 400 mg\\/kg, from gestation days 6 to postnatal day 20. Neurotransmitters such as dopamine (DA) and serotonin (5HT) were extracted from the brains of dams and female offspring, and measured using liquid chromatography. BPA at 400 mg\\/kg was toxic and dosed rats died.

Takeshi HONMA; Muneyuki MIYAGAWA; Megumi SUDA; Rui-Sheng WANG; Kenichi KOBAYASHI; Soichiro SEKIGUCHI



Influence of Dietary Zinc on Lead Toxicity During Gestation and Lactation in the Female Rat1'2  

Microsoft Academic Search

Confirmed pregnant female albino rats received a purified diet containing either 12 or 120 ppm zinc with or without lead (0 or 500 ppm) from day 0 gestation through day 16 of lactation. An 11% reduction in dam weight gain during gestation and a 12% reduction in average pup weight in rats fed the low zinc plus lead diet was



Pre and postnatal bisphenol A treatment results in persistent deficits in the sexual behavior of male rats, but not female rats, in adulthood  

Microsoft Academic Search

Perinatal administration of the endocrine disruptor bisphenol A (BPA) reportedly inhibits the sexual behavior of sexually naïve adult male rats. In order to evaluate the effects of BPA administration during early development on later reproductive behavior, we administered one of five doses of bisphenol A daily to pregnant female rats throughout gestation and lactation, and quantified the appetitive and consummatory

Bryan A. Jones; Jordan J. Shimell; Neil V. Watson



Pharmacokinetic profiling of efavirenz-emtricitabine-tenofovir fixed dose combination in pregnant and non-pregnant rats.  


During pregnancy, the disposition of various drugs is altered due to changes in physiological condition, maternal gastrointestinal absorption, gastric secretion and motility. A fixed dose combination of antiretrovirals is commonly prescribed for the treatment of HIV infection. There is a need to understand the pharmacokinetics and placental transfer of efavirenz-emtricitabine-tenofovir in fixed dose combination during pregnancy. The pharmacokinetics and placental transfer of efavirenz-emtricitabine-tenofovir fixed dose combination was evaluated in timed pregnant and non-pregnant Sprague-Dawley rats at 30, 10, 15 mg/kg p.o., respectively. The plasma, placental tissue, amniotic fluid and fetal tissue concentrations were measured using high performance liquid chromatography combined with tandem mass spectrometric detector (LC-MS/MS). To summarize, the pharmacokinetic profile of efavirenz remained similar in the pregnant and non-pregnant rats. However, a considerable difference in the pharmacokinetics of emtricitabine and tenofovir was observed in pregnant and non-pregnant rats. Efavirenz and emtricitabine showed appreciable placental, amniotic fluid and fetal exposure compared with tenofovir. The present study suggests that a profound impact on antiretroviral pharmacokinetics was observed during pregnancy and there is a need to monitor the exposure levels of each drug when administered as a fixed dose combination during pregnancy. Further studies to explore the pharmacokinetic parameters of fixed dose antiretrovirals during the preclinical stage in a timed-pregnancy rat model are required. Such studies can help in the development of safe and effective medications with a reduced risk of perinatal transmission of HIV-1 infection. PMID:22610784

Nirogi, Ramakrishna; Bhyrapuneni, Gopinadh; Kandikere, Vishwottam; Muddana, Nageswararao; Saralaya, Ramanatha; Komarneni, Prashanth; Mudigonda, Koteshwara; Mukkanti, K



Expression of cytochrome CYP2B1/2 in nonpregnant, pregnant and fetal rats exposed to tobacco smoke.  


Four-month-old female Wistar rats were exposed for 20 days to tobacco smoke obtained from non-filter cigarettes. During the exposure, concentration of tobacco smoke was monitored indirectly by measuring the CO level (1500 mg/m3 air). The efficacy of exposure was assessed by measuring urine nicotine and cotinine levels. Cigarette smoke did not change total cytochrome P450 and b5 protein levels in any of the organs studied, and most of these organs did not show any changes in the activity of reductases associated with these cytochromes. Following exposure to tobacco smoke, fetal rat liver expressed CYP2B1/2 protein; in newborns (day 1) both liver and lung showed CYP2B1/2 protein expression and very low pentoxyresorufin O-dealkylase activity. Western blot analysis of adult liver, lung, heart, but not of brain microsomes, showed that tobacco smoke induced CYP2B1/2 in both nonpregnant and pregnant rats, though its expression was lower in the livers and hearts of pregnant females. In the rat and human placenta, neither rat CYP2B1/2 nor human CYP2B6 showed basal or tobacco smoke-induced expression at the protein level. This study shows clearly that the expression of CYP2B1/2, which metabolizes nicotine and some drugs and activates carcinogens, is controlled in rats by age-, pregnancy-, and tissue-specific regulatory mechanisms. PMID:11996101

Czekaj, P; Wiaderkiewicz, A; Florek, E; Wiaderkiewicz, R



Prenatal androgen excess programs metabolic derangements in pubertal female rats.  


Owing to the heterogeneity in the clinical symptoms of polycystic ovary syndrome (PCOS), the early pathophysiological mechanisms of PCOS remain unclear. Clinical, experimental, and genetic evidence supports an interaction between genetic susceptibility and the influence of maternal environment in the pathogenesis of PCOS. To determine whether prenatal androgen exposure induced PCOS-related metabolic derangements during pubertal development, we administrated 5?-dihydrotestosterone (DHT) in pregnant rats and observed their female offspring from postnatal 4 to 8 weeks. The prenatally androgenized (PNA) rats exhibited more numerous total follicles, cystic follicles, and atretic follicles than the controls. Fasting glucose, insulin, leptin levels, and homeostatic model assessment for insulin resistance were elevated in the PNA rats at the age of 5-8 weeks. Following intraperitoneal glucose tolerance tests, glucose and insulin levels did not differ between two groups; however, the PNA rats showed significantly higher 30- and 60-min glucose levels than the controls after insulin stimulation during 5-8 weeks. In addition, prenatal DHT treatment significantly decreased insulin-stimulated phosphorylation of AKT in the skeletal muscles of 6-week-old PNA rats. The abundance of IR substrate 1 (IRS1) and IRS2 was decreased in the skeletal muscles and liver after stimulation with insulin in the PNA group, whereas phosphorylation of insulin-signaling proteins was unaltered in the adipose tissue. These findings validate the contribution of prenatal androgen excess to metabolic derangements in pubertal female rats, and the impaired insulin signaling through IRS and AKT may result in the peripheral insulin resistance during pubertal development. PMID:23426873

Yan, Xiaonan; Dai, Xiaonan; Wang, Jing; Zhao, Nannan; Cui, Yugui; Liu, Jiayin



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


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 1h. For metabolite identification by (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. PMID:22664346

Schmidt, Tobias; Bertermann, Rüdiger; Rusch, George M; Hoffman, Gary M; Dekant, Wolfgang



The social environment affects behaviour and androgens, but not cortisol in pregnant female guinea pigs.  


In guinea pigs the behaviour of male offspring is infantilized in adulthood, when their mothers had lived in an unstable social environment during pregnancy and lactation (Kaiser and Sachser, Psychoneuroendocrinology, 26 (2001) 503). The present study was conducted to elucidate the mechanisms bringing about this phenomenon. Therefore, the spontaneous behaviour and endocrine parameters of females were compared that either lived in a stable social environment (SSE) during pregnancy (SE-females) or in an unstable social environment (USE) during this period of life (UE-females). The SSE was made by keeping the group composition (one male, five females) constant; in the USE situation (one male, five females) every third day two females from different groups were exchanged. The spontaneous behaviour of the UE-females was recorded on three successive days: the day before, the day of and the day after the transfer from one group to another. The behaviour of the SE-females was recorded at corresponding times. In addition, serum concentrations of cortisol, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) concentrations were determined. After transfer to another group UE-females showed distinctly more orientation behaviour and they received significantly higher amounts of courtship and sexual behaviour from the males than SE-females which remained in their familiar groups. In turn, UE-females displayed significantly higher amounts of urine spray towards the male, a defensive aggressive behavioural pattern. No differences were found in offensive aggressive and socio-positive behaviours between UE- and SE-females. With respect to endocrine parameters the transfer to an unfamiliar group did not cause an increase of cortisol, that is UE- and SE-females did not differ significantly. DHEAS and in part DHEA concentrations, however, were significantly lower in UE- than SE-females. Thus, for the first time it is shown that the social environment during pregnancy has significant effects on the androgen concentrations in female guinea pigs. Moreover, a decrease of androgens in pregnant females may be related to the infantilization of their male offspring. PMID:12445837

Kaiser, Sylvia; Heemann, Kerstin; Straub, Rainer H; Sachser, Norbert



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)



Ethanol inhibits cadmium accumulation in brains of offspring of pregnant rats that consume cadmium  

Microsoft Academic Search

The present study was designed to test the effect of ethanol on cadmium accumulation in tissues of pregnant rats and their offspring. Starting 10 days before mating and continuing until parturition, ethanol (10% v\\/v) was present in the drinking water of half the rats. Cadmium chloride (CdCl2; 50 ppm) was present in the water of half the rats (± ethanol)

Ryszard Brus; Richard M. Kostrzewa; Wieslawa Feli?ska; Andrzej Plech; Ryszard Szkilnik; Jozef Frydrych



In vivo effects of corticotropin-releasing factor in pregnant rats  

Microsoft Academic Search

OBJECTIVE: Our purpose was to study the effects of corticotropin-releasing factor on (1) maternal blood pressure, (2) uterine vasculature, and (3) parturition in pregnant rats. STUDY DESIGN: Infusion minipumps containing vehicle, corticotropin-releasing factor, or ?-helical corticotropin-releasing factor 9-41 (corticotropin-releasing factor receptor antagonist) were inserted subcutaneously in timed pregnant rats on day 16 of gestation. Systolic blood pressure was measured daily

Venu Jain; Shao-Qing Shi; Yuri P. Vedernikov; George R. Saade; Kristof Chwalisz; Robert E. Garfield



The celiac ganglion modulates LH-induced inhibition of androstenedione release in late pregnant rat ovaries  

Microsoft Academic Search

BACKGROUND: Although the control of ovarian production of steroid hormones is mainly of endocrine nature, there is increasing evidence that the nervous system also influences ovarian steroidogenic output. The purpose of this work was to study whether the celiac ganglion modulates, via the superior ovarian nerve, the anti-steroidogenic effect of LH in the rat ovary. Using mid- and late-pregnant rats,

Marilina Casais; Silvia M Delgado; Zulema Sosa; Carlos M Telleria; Ana M Rastrilla



Placental transfer of mercury in pregnant rats which received dental amalgam restorations  

Microsoft Academic Search

Mercury vapor released from one, two and four amalgam restorations in pregnant rats and mercury concentrations in maternal and fetal organs were studied. Dental treatment was given on day 2 of pregnancy. Mercury concentration in air samples drawn from each metabolism chamber with a rat were measured serially for 24 h on days 2, 8 and 15 of pregnancy. On

Yoshifumi Takahashi; Shozo Tsuruta; Michitoshi Arimoto; Hironori Tanaka; Minoru Yoshida



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.

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



Effects of streptozotocin-induced diabetes on the uterine adrenergic nerve function in pregnant rats  

Microsoft Academic Search

Pregnancy-induced diabetes mellitus poses one of the greatest challenges in obstetrical practice. The direct action of diabetes on the myometrial adrenergic functions has not been completely characterized. Accordingly, the present study relates to the impact of experimentally induced diabetes on the presynaptic functions of the rat uterus in relation to gestational age. Experiments were carried out on non-pregnant, early-pregnant (day

G. Falkay; G. Spiegl; D. Csonka; I. Zupkó



Disseminated intravascular coagulation induced by progesterone in the pregnant rat. Prevention by estogens.  

PubMed Central

Fatal disseminated intravascular coagulation (DIC) was induced in female rats by administration of progesterone in late pregnacy. This prevented parturition, with intrauterine fetal death 2 to 4 days past term and subsequent retention of dead fetuses. Concomitantly with or closely following the intrauterine death of their litters, a large proportion of pregnant rats died with histologically evident DIC. Administration of cortisone, heparin, or disoumarin did not prevent DIC, and xi-aminocaproic acid, acetylsalicylic acid, or an onion-rich diet tended to increase its incidence. Antibiotic regimens gave variable results, with significant decrease in DIC only with a combination of two wide-spectrum penicillins. Neomycin and polymyxin had little effect on susceptible Sprague-dawley derived rats, but polymxin caused a significant increase in DIC in a resistant strain of hooded rats. Fatal maternal DIC was completely prevented only by use of natural or synthetic estrogens concurrently with progesterone, although this did not alter the sequence of abnormally prolonged pregnacy with intrauterine fetal death and retention of dead fetuses. Potencies of estrogens varied greatly, but all compounds tested prevented DIC at adequate dosage levels. Diethylstilbestrol, the most potent drug tested, was completely protective at 1 mug daily given subcutaneously. beta-Estradiol was the most effective natural estrogen, giving complete protection with a 10-mug daily subcutaneous injection. Estrogens were much more potent by subcutaneous injection than by oral ingestion, and toxic side effects were sometimes noted with higher levels of the latter. For estrogen therapy to be effective, it was necessary to begin its use before the expected onset of DIC, and in no instance was there evidence of reversal of this process after signs of illness were observed. Images Figure 3 Figure 4 Figure 1 Figure 2

Stamler, F. W.



Disseminated intravascular coagulation induced by progesterone in the pregnant rat. Prevention by estogens.  


Fatal disseminated intravascular coagulation (DIC) was induced in female rats by administration of progesterone in late pregnacy. This prevented parturition, with intrauterine fetal death 2 to 4 days past term and subsequent retention of dead fetuses. Concomitantly with or closely following the intrauterine death of their litters, a large proportion of pregnant rats died with histologically evident DIC. Administration of cortisone, heparin, or disoumarin did not prevent DIC, and xi-aminocaproic acid, acetylsalicylic acid, or an onion-rich diet tended to increase its incidence. Antibiotic regimens gave variable results, with significant decrease in DIC only with a combination of two wide-spectrum penicillins. Neomycin and polymyxin had little effect on susceptible Sprague-dawley derived rats, but polymxin caused a significant increase in DIC in a resistant strain of hooded rats. Fatal maternal DIC was completely prevented only by use of natural or synthetic estrogens concurrently with progesterone, although this did not alter the sequence of abnormally prolonged pregnacy with intrauterine fetal death and retention of dead fetuses. Potencies of estrogens varied greatly, but all compounds tested prevented DIC at adequate dosage levels. Diethylstilbestrol, the most potent drug tested, was completely protective at 1 mug daily given subcutaneously. beta-Estradiol was the most effective natural estrogen, giving complete protection with a 10-mug daily subcutaneous injection. Estrogens were much more potent by subcutaneous injection than by oral ingestion, and toxic side effects were sometimes noted with higher levels of the latter. For estrogen therapy to be effective, it was necessary to begin its use before the expected onset of DIC, and in no instance was there evidence of reversal of this process after signs of illness were observed. PMID:65916

Stamler, F W



Amphetamine sensitization in reproductively experienced female rats.  


Recent studies have supported the hypothesis that pregnancy and parturition are associated with altered sensitivity of brain dopamine systems. An increased behavioral sensitivity to a direct-acting D1/D2 receptor agonist (apomorphine) has also been observed several weeks after lactation, suggesting that these adaptations are long-lasting. To further characterize this phenomenon, the effects of reproductive experience on behavioral sensitization to an indirect-acting dopamine agonist (amphetamine) in female rats were studied. In two separate experiments, nulliparous and primiparous (12-16 weeks post-weaning) female rats were pretreated with amphetamine (1.0 or 5.0mg/kg) or vehicle (saline) once daily for 5 consecutive days. After 10 days of withdrawal, all animals were challenged with a low dose of amphetamine (25% of pretreatment dose). Locomotor activity was measured following each drug or vehicle administration. Locomotor sensitization to amphetamine challenge was observed in all animals pretreated with 1mg/kg, regardless of reproductive experience. In contrast, primiparous animals pretreated with 5mg/kg amphetamine displayed a significantly larger locomotor response to the challenge compared to nulliparous controls. The findings indicate enhanced behavioral sensitization to amphetamine in reproductively experienced rats, and confirm previous reports of lasting adaptations of dopamine systems following pregnancy and lactation. PMID:21821097

Byrnes, John J; Bridges, Robert S; Byrnes, Elizabeth M



Phasic Oscillations of Extracellular Potassium (Ko) in Pregnant Rat Myometrium  

PubMed Central

K-sensitive microelectrodes were used to measure K+ within the extracellular space (Ko) of pregnant rat myometrium. Contractile activity was monitored by measuring either force or bioelectrical signals. Single and double-barreled electrodes were used. Double-barreled electrodes allowed monitoring of electrical activity 15 microns from the site of Ko measurement. From double-barreled electrode experiments, the bioelectrical burst started first, and then Ko began to rise 0.6 ± 0.1 seconds later. This delay indicates that K+ leaves the cells in response to local electrical activity rather than vice versa. Four control experiments were performed to assess the influence of electrical artifacts caused by tissue motion on Ko values. When observed, artifacts were negative and transient, and hence would result in an underestimation of Ko rises. Artifacts were minimized when tissue motion was minimized by fixing the tissue at both ends. At 37°C, 7 single barreled experiments and 45 contractions were analyzed. Resting Ko was within 1 mM of bath K+ (5 mM) at the beginning and end of the experiments. Ko rose during the contraction, fell after the completion of the contraction, and normalized before the next contraction began. Peak Ko values observed during force production were 18.8 ± 5.9 mM, a value high enough to modulate tissue-level electrical activity. Ko required 15.7 ± 2.8 seconds to normalize halfway (t50). Six experiments expressing 38 contractions were performed at 24°C. The contraction period was longer at 24°C. Values for peak Ko (26.2 ± 9.9 mM) and t50 (29.8±16.2 sec) were both larger than at 37°C (p<0.0003 for both). The direct relationships between peak Ko, t50 and the contraction period, suggest elevations in Ko may modulate contraction frequency. The myometrial interstitial space appears to be functionally important, and Ko metabolism may participate in cell-cell interactions.

Young, Roger C.; Goloman, Gabriela



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))



Runaway and Pregnant: Risk Factors Associated with Pregnancy in a National Sample of Runaway/Homeless Female Adolescents  

PubMed Central

Purpose Homeless youth are at particularly high risk for teen pregnancy; research indicates as many as 20% of homeless young women become pregnant. These pregnant and homeless teens lack financial resources and adequate health care, resulting in increased risk for low– birth-weight babies and high infant mortality. This study investigated individual and family-level predictors of teen pregnancy among a national sample of runaway/homeless youth in order to better understand the needs of this vulnerable population. Methods Data from the Runaway/Homeless Youth Management Information System (RHY MIS) provided a national sample of youth seeking services at crisis shelters. A sub-sample of pregnant females and a random sub-sample (matched by age) of nonpregnant females comprised the study sample (N= 951). Chi-square and t tests identified differences between pregnant and nonpregnant runaway females; maximum likelihood logistic regression identified individual and family-level predictors of teen pregnancy. Results Teen pregnancy was associated with being an ethnic minority, dropping out of school, being away from home for longer periods of time, having a sexually transmitted disease, and feeling abandoned by one's family. Family factors, such as living in a single parent household and experiencing emotional abuse by one's mother, increased the odds of a teen being pregnant. Conclusions The complex problems associated with pregnant runaway/homeless teens create challenges for short-term shelter services. Suggestions are made for extending shelter services to include referrals and coordination with teen parenting programs and other systems of care.

Thompson, Sanna J.; Bender, Kimberly A.; Lewis, Carol M.; Watkins, Rita



Disposition of Orally Administered 2,2Bis(4-hydroxyphenyl)propane (Bisphenol A) in Pregnant Rats and the Placental Transfer to Fetuses  

Microsoft Academic Search

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 36µg\\/g) 20 min after the administration and gradually decreased. The levels were 2-5% of the

Osamu Takahashi; Shinshi Oishi



Prolactin inhibition of pregnant mare's serum stimulated follicle development in the rat ovary.  


Prolactin (PRL) effects on the female reproductive system have been presumed to occur primarily at the hypothalamic-pituitary level. The following studies were designed to evaluate whether PRL can directly alter gonadotropin actions at the ovarian level. In the first experiment, 10 groups of 7 cycling adult female rats were given a daily dose of pregnant mare's serum (PMS: 25 IU) and either saline (SAL) or PRL (0.25, 0.8, 2.5, 8, or 25 micrograms) twice daily for 4 days. In the second experiment, PMS (6 doses: 0-75 IU/d; 16 animals/dose) was administered to all animals while half the animals at each PMS dose received PRL (25 micrograms twice daily) and half received an equal volume of diluent. Finally, hypophysectomized (hypox) adult rats (n = 5-6/group) received 25 IU PMS/d and PRL (0-75 micrograms) twice daily. An additional group received 0 PRL and 0 PMS. Ovarian weight and histology were evaluated at the completion of each study. In the first experiment, PRL inhibited PMS-stimulated ovarian weight gain in a dose-dependent manner (p less than 0.01). Numbers of preantral (p less than 0.005) and antral (p less than 0.05) follicles were decreased in animals receiving an inhibitory dose of PRL (25 micrograms BID) compared to controls. In the second experiment PRL (25 micrograms BID) again inhibited PMS-stimulated ovarian weight (p less than 0.01) at all doses of PMS. Finally, in hypox animals, PRL inhibited PMS-stimulated ovarian weight gain (25 and 75 micrograms PRL: p = 0.001), and mean number (p less than 0.001) and diameter (p less than 0.001) of antral ovarian follicles (8-75 micrograms PRL) compared to controls. In summary, administration of PRL inhibited PMS-stimulated ovarian weight gain, and antral follicle diameter (in hypox animals only) and number in adult female rats suggesting that in states of hyperprolactinemia, PRL alters gonadotropin-mediated activities (i.e., folliculogenesis) directly at the ovarian level in addition to its hypothalamic and pituitary actions. PMID:2102466

Larsen, J L; Bhanu, A; Odell, W D



Metal concentrations in blood and hair in pregnant females in southern Sweden.  


The study described here was comprised of 100 pregnant females from two prenatal care units at the cities of Hassleholm and Simrishamn in southern Sweden. It included a questionnaire as well as whole blood (total mercury, cadmium, and lead) and hair (total mercury) sampling (collection period 2002-2003). The median values of total mercury (B-Hg 0.70 microg/L; range 0.27-2.1 microg/L), cadmium (0.30 microg/L, 0.05-4.8 microg/L) and lead (11.0 microg/L, 4.2-79 microg/L) in whole blood were low in the total material, as were the hair mercury concentrations (Hair-Hg 0.22 microg/g, 0.04-0.83 microg/g). In a multiple linear regression model, B-Hg was related to the number of fish meals per week and to the number of occlusal amalgam fillings (multiple r = 0.51; p < .001). The levels of mercury, cadmium, and lead in whole blood were lower than suggested biological reference intervals, and did not indicate risks for adverse health effects. PMID:20104833

Gerhardsson, Lars; Lundh, Thomas


Reversal of prenatal morphine exposure-induced memory deficit in male but not female rats.  


Impaired memory performance in offspring is one of the long-lasting neurobehavioral consequences of prenatal opiate exposure. Here, we studied the effects of prenatal morphine exposure on inhibitory avoidance memory performance in male and female offspring and also investigated whether these deficits are reversible during the postnatal development. Pregnant Wistar rats received morphine sulfate through drinking water, from the first day of gestation up to the day 13, M????, or to the time of delivery, M????. Four- and ten-week-old (adolescent and adult, respectively) male and female offspring were subjected to behavioral assays and then analysis of proteins involved in apoptosis or in synaptic plasticity. Results revealed that adolescent and adult female rats failed in passive avoidance retention task in both M???? and M???? groups. Adolescent and adult male offspring were similar to control animals in M???? group. However M???? impaired retention task in prepubertal male offspring, and this memory loss was repaired in postpubertal stage. Consistently, Bax/Bcl-2 ratio and cleaved caspase-3 were significantly increased in both M???? and M???? adolescent and adult female rats, but only in M???? adolescent male rats. Furthermore, prenatal morphine exposure reduced the expression of brain-derived neurotrophic factor precursor protein in adolescent and adult female offspring and also decreased p-ca(2+)/calmodulin-dependent kinase II/ca(2+)/calmodulin-dependent kinase II ratio in adolescent male and female rats. Altogether, the results show that prenatal morphine exposure, depending on the time or duration of exposure, has distinct effects on male and female rats, and postnatal development may reverse these deficits more likely in males. PMID:22864979

Nasiraei-Moghadam, Shiva; Sherafat, Mohammad Amin; Safari, Mir-Shahram; Moradi, Fatemeh; Ahmadiani, Abolhassan; Dargahi, Leila



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



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

Almeida, Cristhiano Sibaldo de; 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



Pharmacokinetics of Intravenous Acyclovir, Zidovudine, and Acyclovir-Zidovudine in Pregnant Rats  

Microsoft Academic Search

The pharmacokinetics and placental transfer of acyclovir and zidovudine monotherapies and acyclovir- zidovudine combination therapy were compared in the pregnant rat. Timed-pregnancy Sprague-Dawley rats were used for the study. Doses of 60 mg of each drug\\/kg of body weight in monotherapy and in combination therapy were given by intravenous bolus, and samples of maternal plasma, amniotic fluid, fetal tissue, and

Stacy D. Brown; Michael G. Bartlett; Catherine A. White



Nonthermal effects of mobile-phone frequency microwaves on uteroplacental functions in pregnant rats  

Microsoft Academic Search

Exposure to high-density microwaves can cause detrimental effects on the testis, eye, and other tissues, and induce significant biologic changes through thermal actions. To examine nonthermal effect of continuous wave (CW) 915MHz microwaves used in cellular phones, we compared the effects of microwaves with those of heat. Thirty-six pregnant rats were assigned to six groups: rats exposed to microwaves at

Hiroyuki Nakamura; Ichiyo Matsuzaki; Kotaro Hatta; Yoshitaka Nobukuni; Yasuhiro Kambayashi; Keiki Ogino



Effect of metyrapone administration in pregnant rats on monoamine concentration in fetal brain  

Microsoft Academic Search

Studies performed in our laboratory indicate that the adrenal deprivation during gestation can greatly influence the fetal catecholamines development in several cerebral areas. The present study was undertaken to determine wether the administration of metyrapone to pregnant rats affects the content of monoamines in fetal brain at term. To test wether the content of monoamines in fetal brain is regulated,

M. L. Leret; M T. Antonio; R. M. Arahuetes




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 ...


Functional Adaptation in Female Rats: The Role of Estrogen Signaling  

PubMed Central

Background Sex steroids have direct effects on the skeleton. Estrogen acts on the skeleton via the classical genomic estrogen receptors alpha and beta (ER? and ER?), a membrane ER, and the non-genomic G-protein coupled estrogen receptor (GPER). GPER is distributed throughout the nervous system, but little is known about its effects on bone. In male rats, adaptation to loading is neuronally regulated, but this has not been studied in females. Methodology/Principal Findings We used the rat ulna end-loading model to induce an adaptive modeling response in ovariectomized (OVX) female Sprague-Dawley rats. Rats were treated with a placebo, estrogen (17?-estradiol), or G-1, a GPER-specific agonist. Fourteen days after OVX, rats underwent unilateral cyclic loading of the right ulna; half of the rats in each group had brachial plexus anesthesia (BPA) of the loaded limb before loading. Ten days after loading, serum estrogen concentrations, dorsal root ganglion (DRG) gene expression of ER?, ER?, GPER, CGRP?, TRPV1, TRPV4 and TRPA1, and load-induced skeletal responses were quantified. We hypothesized that estrogen and G-1 treatment would influence skeletal responses to cyclic loading through a neuronal mechanism. We found that estrogen suppresses periosteal bone formation in female rats. This physiological effect is not GPER-mediated. We also found that absolute mechanosensitivity in female rats was decreased, when compared with male rats. Blocking of adaptive bone formation by BPA in Placebo OVX females was reduced. Conclusions Estrogen acts to decrease periosteal bone formation in female rats in vivo. This effect is not GPER-mediated. Gender differences in absolute bone mechanosensitivity exist in young Sprague-Dawley rats with reduced mechanosensitivity in females, although underlying bone formation rate associated with growth likely influences this observation. In contrast to female and male rats, central neuronal signals had a diminished effect on adaptive bone formation in estrogen-deficient female rats.

Sample, Susannah J.; Racette, Molly A.; Hao, Zhengling; Thomas, Cathy F.; Behan, Mary; Muir, Peter



Calcium and phosphorus metabolism in pregnant rats ingesting a high protein diet.  


In both nonpregnant and pregnant rats as dietary protein increased, increases in urinary calcium were observed. In nonpregnant rats, urinary calcium excretion was significantly increased as the level of dietary protein increased from 16 to 24 to 32%, but in the pregnant rats increases in urinary calcium as protein intake was raised from 24 to 32% were not observed. The present data indicated that the increase in urinary calcium was probably a result of a shift of the endogenous excretion of calcium from the feces to urine and not from intestinal absorption of dietary calcium or bone resorption of calcium. Responses of parameters indicative of intestinal absorption either were inconsistent or were not affected as protein intake increased. A high protein diet had no effect on the amount of calcium lost from the bones. Although the results were inconsistent with regard to calcium retention, a positive calcium balance was achieved by all rats fed the three different levels of dietary protein. Urinary phosphorus excretion increased with increased protein intake, but the response was modified by the physiological state. In pregnant rats, the increase from 16 to 24% dietary protein had a greater influence on urine phosphorus than the increase from 24 to 32%; this pattern was reversed in the nonpregnant rats. PMID:7441372

Graves, K L; Wolinsky, I



[Distribution of vanadium in tissues of nonpregnant and pregnant Wistar rats].  


This paper reports tissue distribution of vanadium in nonpregnant and pregnant Wistar rats. The experimental results showed that vanadium concentrations in nonpregnant rats were respectively from high to low: I. no treatment: ovary greater than uterus greater than kidney greater than lung greater than heart muscle greater than spleen greater than brain greater than liver greater than blood; II. 4h after single i.p. injection of V2O5 (5 mg/kg): kidney greater than ovary greater than liver greater than bone greater than uterus greater than lung greater than heart muscle greater than spleen greater than brain greater than blood. The results suggest that female genital organs are important organs in distribution of vanadium. The kidney is a main excretory organ. After 24h of treatment, a larger amount of vanadium in body has been excreted. Vanadium can pass through blood-brain barrier. Distribution of vanadium on gestation days 12 after 4h single i.p. injection of V2O5 (5 mg/kg) is: kidney greater than ovary greater than uterus greater than placenta greater than liver greater than fetus greater than bone greater than heart muscle greater than lung greater than brain greater than spleen greater than blood; on gestation days 16-18 after 4h single i.p. injection of V2O5 (5 mg/kg) is: kidney ovary greater than placenta greater than lung greater than bone greater than uterus greater than heart muscle greater than spleen greater than fetus greater than liver greater than brain greater than blood; after 24h (on gestation days 16-18) is: kidney greater than ovary greater than placenta greater than spleen greater than bone greater than lung greater than liver greater than fetus heart muscle greater than brain blood.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1786960

Li, S; Zhang, T; Yang, Z; Gou, X



Response Latencies of Female Rats during Sexual Intercourse  

Microsoft Academic Search

A female rat, by operating a lever, causes the presentation of a potent male rat and subsequent sexual contact. The female shows contact-response latencies that vary according to the nature of the contact. Latencies after ejaculations are longer than those after intromissions, which in turn exceed those after mounts.

Gordon Bermant



SAF values for internal photon emitters calculated for the RPI-P pregnant-female models using Monte Carlo methods  

PubMed Central

Estimates of radiation absorbed doses from radionuclides internally deposited in a pregnant woman and her fetus are very important due to elevated fetal radiosensitivity. This paper reports a set of specific absorbed fractions (SAFs) for use with the dosimetry schema developed by the Society of Nuclear Medicine’s Medical Internal Radiation Dose (MIRD) Committee. The calculations were based on three newly constructed pregnant female anatomic models, called RPI-P3, RPI-P6, and RPI-P9, that represent adult females at 3-, 6-, and 9-month gestational periods, respectively. Advanced Boundary REPresentation (BREP) surface-geometry modeling methods were used to create anatomically realistic geometries and organ volumes that were carefully adjusted to agree with the latest ICRP reference values. A Monte Carlo user code, EGS4-VLSI, was used to simulate internal photon emitters ranging from 10 keV to 4 MeV. SAF values were calculated and compared with previous data derived from stylized models of simplified geometries and with a model of a 7.5-month pregnant female developed previously from partial-body CT images. The results show considerable differences between these models for low energy photons, but generally good agreement at higher energies. These differences are caused mainly by different organ shapes and positions. Other factors, such as the organ mass, the source-to-target-organ centroid distance, and the Monte Carlo code used in each study, played lesser roles in the observed differences in these. Since the SAF values reported in this study are based on models that are anatomically more realistic than previous models, these data are recommended for future applications as standard reference values in internal dosimetry involving pregnant females.

Shi, C. Y.; Xu, X. George; Stabin, Michael G.



Minor pathological changes are induced by naltrexone-poly(DL-lactide) implants in pregnant rats.  


Oral naltrexone is used to treat alcohol and heroin dependence but is associated with poor patient compliance. Sustained-release preparations have been developed to overcome noncompliance. Many sustained-release preparations are composed of polymers combined with naltrexone. Limited data indicate that polymers induce variable levels of tissue reactivity and that naltrexone may increase this effect. A slow-release subcutaneous naltrexone-poly (DL-lactide) implant is currently being trialed to treat heroin dependence in Western Australia. A minority of women fall pregnant and, although tissue reactivity in nonpregnant humans is relatively minor, detailed chronological data during pregnancy are lacking. Histological changes in pregnant rats were assessed; a single active tablet containing poly[trans-3,6-dimethyl-1,4-dioxyane-2,5-dione] (DL-lactide) loaded with 25 mg of naltrexone was implanted subcutaneously, and tissue response was compared with inactive polymer implantation. Rats were timed mated at 13-26 days postimplant. Tissue assessment up to 75 days by a pathologist showed that naltrexone induced chronic inflammatory response in a dose-dependent manner, although still at a low level. Furthermore, for inactive implants, minimal foreign body reaction and fibrosis, together with low-level inflammation, suggested good long-term biocompatibility. We conclude that the Australian naltrexone-poly(DL-lactide) implant is tolerated in pregnant rats, reinforcing its potential role for managing alcohol and heroin dependence in pregnant humans. PMID:19097147

Farid, W O; McCallum, D; Tait, R J; Dunlop, S A; Hulse, G K



Validação do Índice da Função Sexual Feminina em grávidas brasileiras Validation of the Female Sexual Function Index in Brazilian pregnant women  

Microsoft Academic Search

PURPOSE: to translate and to validate the Female Sexual Function Index (FSFI) for Brazilian pregnant women. METHODS: ninety-two pregnant women attended at a low risk prenatal clinic, with diagnosis of the pregnancy confirmed by precocious ultrasonography, participated in the research. Initially, we translated the FSFI questionnaire for Portuguese language (of Brazil) in agreement with the international criteria. Cultural, conceptual and



Fetal programming of adult hypertension in female rat offspring exposed to androgens in utero  

PubMed Central

Aims The influence of prenatal factors on the development of arterial hypertension has gained considerable interest in recent years. We examined the effects of prenatal testosterone treatment on blood pressure in adult female rats. Further, to define the mechanisms whereby blood pressure may be raised, we examined vascular endothelial function and nitric oxide synthesis. Methods and Results Testosterone propionate (0.5mg/kg/day;SC) or vehicle was administered to pregnant Sprague-Dawley rats from gestational day 15–19. Maternal feed intake and plasma levels of steroid hormones were measured in the dams. In the female offspring, birth weight, growth rate, blood pressure, vascular reactivity, eNOS expression, and nitric oxide production were examined. In the pregnant rats, testosterone-treatment increased plasma testosterone levels by 2-fold without any significant changes in 17?-estradiol, progesterone and corticosterone levels. Testosterone-treatment did not affect maternal feed intake. The pups born to testosterone mothers were smaller in size but exhibited catch-up growth. The blood pressure in the testosterone offspring at 6 months of age was significantly higher compared to controls. Endothelium-intact mesenteric arteries from testosterone group exhibited increased contractile responses to phenylephrine, decreased vasodilation to acetylcholine and unaltered responses to sodium nitroprusside in comparison to control rats. Testosterone rats demonstrated decreased expression for eNOS, and reduced nitric oxide production. Conclusions Our data show that elevated plasma maternal testosterone levels: (1) causes low birth weight followed by catch-up growth and hypertension in female offspring; (2) alters endothelium-dependent vascular responses. The endothelial dysfunction is associated with decreased activity/expression of eNOS.

Sathishkumar, K.; Elkins, Rebekah; Yallampalli, Uma; Balakrishnan, Meena; Yallampalli, Chandrasekhar



Toxicological assessment of beta-lapachone on organs from pregnant and non-pregnant rats.  


Naphthoquinones have been studied extensively due to their activity as topoisomerase inhibitors. These enzymes are critical to DNA replication in cells. beta-Lapachone (beta-lap) is an o-naphthoquinone chemically obtained from lapachol. This work results in a toxicological evaluation of beta-lap in Wistar rats observing the following parameters: teratology, histology, hematology and serum biochemistry. The data demonstrate teratogenic action at the doses used, as well as hematological alterations in the total leukocytes, monocytes and segmented. The biochemical data demonstrated an increase in gamma glutamyl transferase, alkaline phosphatase and glutamate pyruvate transaminase levels. Histological study showed significant alterations in the spleen, however, the liver and kidney did not present significant alterations. PMID:19197915

de Almeida, Edvaldo Rodrigues; Lucena, Flávia Raquel Santos; Silva, Camilla Vila Nova Soares; da Silva Costa-Junior, Wilson; Cavalcanti, Jouse Bezerra; Couto, Gerald Bosco Lindoso; da Silva, Luiz Lúcio Soares; da Mota, Diógenes Luís; da Silveira, Alex Benício; de Sousa Filho, Samuel Daniel; da Silva, Aldo Cezar Passilongo



Effects of weight cycling in female rats.  


Recent reports indicate that weight cycling (repeated periods of weight gain and loss) cause an organism to become an energy conserver, meaning that the organism gains weight more quickly and loses weight more slowly during subsequent weight cycles. The effects of weight cycling on rates of weight gain and loss, caloric efficiency, and ad lib wheel running were investigated with three groups of adult female rats: 1) cycling (cycled twice); 2) maturity control (cycled once); and 3) chow control (not cycled). The cycled group evidenced weight-gain periods of 36 and 21 days, respectively, and showed a significant increase in food efficiency during the second weight-gain period, relative to the first. There was no evidence that maturation was responsible for this phenomenon. Time required to lose weight and ad lib wheel running were not influenced by weight cycling. These findings suggest that weight cycling may make maintenance of normal weight more difficult and have implications for human weight-control programs. PMID:2623063

Archambault, C M; Czyzewski, D; Cordua y Cruz, G D; Foreyt, J P; Mariotto, M J



Release of mercury from dental amalgam fillings in pregnant rats and distribution of mercury in maternal and fetal tissues  

Microsoft Academic Search

Mercury vapor released from a single amalgam restoration in pregnant rats and mercury concentrations in maternal and fetal rat tissues were studied. Dental treatment was given on day 2 of pregnancy. Mercury concentration in air sample drawn from the metabolism chamber with the rat was measured serially for 24 h on days 2, 8 and 15 of pregnancy. An average

Yoshifumi Takahashi; Shozo Tsuruta; Jiro Hasegawa; Yoichiro Kameyama; Minoru Yoshida



Effects of intermittent hypoglycaemia in pregnant rats on the functional development of the pancreatic B-cells of their offspring  

Microsoft Academic Search

Summary  Intermittent hypoglycaemia was induced by insulin injections into pregnant rats. At birth, the pups body weight and pancreatic insulin content were slightly but significantly decreased. In contrast, the B-cells of these newborn rats responded more markedly to a glucose challenge than the controls. The pancreases of the insulin injected rats were grearly depleted of insulin, possibly because of feedback inhibition

F. Sodoyez-Goffaux; J.-C. Sodoyez



[Comparative analysis of cerebral blood flow autoregulation in pregnant and nonpregnant rats].  


It is known, that disturbances in functioning of cerebral blood flow autoregulation during pregnancy may cause severe neurological complications in case of hypertensive episodes. The aim of this study was comparison of autoregulatory responses of cerebral blood flow in pregnant and nonpregnant rats and analysis of their possible mechanisms. Experiments were carried out on two groups of nonpregnant white rats, and two groups of late-pregnant. All test on autoregulation of cerebral blood flow were provided in conditions of acute experiment under chloral hydrate anesthesia. Gradual changes in systemic arterial pressure were caused by occlusion of abdominal aorta by means of catheter with inflatable tip. The local cerebral blood flow was registered using Hydrogen Clearance technique. Before beginning of autoregulatory tests two groups of animals were treated with nitric oxide synthase inhibitor L-NAME. It was established that in late-pregnancy the cerebral blood flow autoregulatory curve in comparison with nonpregnant animals is shifted to the low levels of systemic arterial pressure. Inhibition of nitric oxide synthase by L-NAME caused the shift of autoregulatory curve to the high levels of systemic arterial pressure in both nonpregnant and pregnant animals. Besides, the differences in autoregulatory responses between nonpregnant and pregnant animals taking place in untreated by L-NAME groups were completely eliminated. These finding allow concluding that in late-pregnancy the shift of cerebral blood flow autoregulatory curve to low levels of systemic arterial pressure is caused by increased production of nitric oxide. PMID:19202232

Dzhanelidze, M A



Estrogen normalizes perinatal nicotine-induced hypertensive responses in adult female rat offspring.  


Perinatal nicotine exposure caused a sex-dependent heightened vascular response to angiotensin II (Ang II) and increased blood pressure in adult male but not in female rat offspring. The present study tested the hypothesis that estrogen normalizes perinatal nicotine-induced hypertensive response to Ang II in female offspring. Nicotine was administered to pregnant rats via subcutaneous osmotic minipumps from day 4 of gestation to day 10 after birth. Ovariectomy and 17?-estradiol replacement were performed on 8-week-old female offspring. At 5 months of age, Ang II-induced blood pressure responses were not changed by nicotine treatment in the sham groups. In contrast, nicotine significantly enhanced Ang II-induced blood pressure responses as compared with saline control in the ovariectomy groups, which was associated with increased Ang II-induced vascular contractions. These heightened responses were abrogated by 17?-estradiol replacement. In addition, nicotine enhanced Ang II receptor type I, NADPH (nicotinamide adenine dinucleotide phosphate) oxidase type 2 protein expressions, and reactive oxygen species production of aortas as compared with saline control in the ovariectomy groups. Antioxidative agents, both apocynin and tempol, inhibited Ang II-induced vascular contraction and eliminated the differences of contractions between nicotine-treated and control ovariectomy rats. These findings support a key role of estrogen in the sex difference of perinatal nicotine-induced programming of vascular dysfunction, and suggest that estrogen may counteract heightened reactive oxygen species production, leading to protection of females from development programming of hypertensive phenotype in adulthood. PMID:23529162

Xiao, Daliao; Huang, Xiaohui; Yang, Shumei; Zhang, Lubo



Behavioral perturbations after prenatal neurogenesis disturbance in female rat.  


The exposure to methylazoxymethanol (MAM) at embryonic day 17 (E17) results in behavioral anomalies in male rats that mimic several features of schizophrenia, including their emergence after puberty. Given that both men and women are likely to develop this illness and that currently no animal model is validated for females, we examined the behavioral consequences of E17 MAM exposure in female rats. We compared E17 MAM- and saline-exposed female rats before and/or after puberty for spontaneous activity, alternance and spatial recognition (Y-maze), spatial learning (Morris water maze), and sensory gating using the prepulse inhibition task. MAM-exposed female rats exhibited a significant increase in spontaneous locomotor activity in a novel environment, compared to sham animals, which emerged only after puberty. They also had deficits in spontaneous alternation performance and spatial recognition in a Y-maze as well as reference memory deficits in a Morris water maze task. Lastly, MAM-exposed female rats spent significantly less time in social interaction at both pre- and post-puberty and had a deficit in prepulse inhibition of the startle reflex (PPI) at adulthood. In conclusion, the present results show that, in female rat, exposure to MAM at E17 results in a pattern of behavioral changes that, on the whole, mimic positive, negative, and cognitive dimensions of schizophrenia. E17 MAM exposure thus appears to be a valid model for schizophrenia in both males and females. PMID:19384565

Hazane, Franck; Krebs, Marie-Odile; Jay, Thérèse M; Le Pen, Gwenaëlle



Electrophysiological properties of membrane currents in single myometrial cells isolated from pregnant rats  

Microsoft Academic Search

The whole-cell voltage-clamp method was applied to single smooth muscle cells prepared from the longitudinal layer of the pregnant rat myometrium (17–20 days of gestation). It was found that the transient inward current mainly consists of Ca2+ current, because the removal of Ca2+ ions from the external medium and 10 µM nifedipine eliminated this inward current. Its steady-state inactivation curve

Hiroshi Miyoshi; Takeshi Urabe; Atsushi Fujiwara



Teratogenicity and metabolism of water-soluble forms of vitamin A in the pregnant rat  

Microsoft Academic Search

Retinoyl β-glucuronide, unlike retinoic acid, has been shown to be non-teratogenic when administered orally, even in large doses, to pregnant rats. The degree to which water-solubility is associated with low teratogenicity is not known. Other water-soluble forms of vitamin A have now been synthesized in our laboratory and are being evaluated for teratogenicity. New water-soluble forms of vitamin A were

D. B. Gunning; A. B. Barua; J. A. Olson



Antifertility effects of physalis alkekengi alcoholic extract in female rat  

Microsoft Academic Search

Background: Physalis alkekengi (P. alkekengi)has been used as an abortive plant in Iranian traditional medicine for many years. Objective: To investigate the effects of P.alkekengi on the fertility rate in female rats. Material and Methods: In this experimental study, 40 female albino rats were divided randomly into two groups; group 1\\/for investigating the implantation sites and group 2\\/ for investigating

Azadeh Montaserti; Maryam Pourheydar; Mozafar Khazaei; Rostam Ghorbani


Fatal air embolism occurring during consensual intercourse in a non-pregnant female  

Microsoft Academic Search

Death from air embolism during pregnancy has been reported following sexual activity, particularly vaginal insufflation. We report a death from air embolism in a non-pregnant woman during consensual penile intercourse, in a position with the pelvis elevated above heart level. Air is thought to have entered the veins via a vaginal laceration, which occurred during digital foreplay.

David W Sadler; Derrick J Pounder



Voluntary exercise in pregnant rats positively influences fetal growth without initiating a maternal physiological stress response.  


The effects of increased physical activity during pregnancy on the health of the offspring in later life are unknown. Research in this field requires an animal model of exercise during pregnancy that is sufficiently strenuous to cause an effect but does not elicit a stress response. Previously, we demonstrated that two models of voluntary exercise in the nonpregnant rat, tower climbing and rising to an erect bipedal stance (squat), cause bone modeling without elevating the stress hormone corticosterone. In this study, these same models were applied to pregnant rats. Gravid Wistar rats were randomly divided into three groups: control, tower climbing, and squat exercise. The rats exercised throughout pregnancy and were killed at day 19. Maternal stress was assessed by fecal corticosterone measurement. Maternal bone and soft tissue responses to exercise were assessed by peripheral quantitative computed tomography and dual-energy X-ray absorptiometry. Maternal weight gain during the first 19 days of pregnancy was less in exercised than in nonexercised pregnant control rats. Fecal corticosterone levels did not differ between the three maternal groups. The fetuses responded to maternal exercise in a uterine position-dependent manner. Mid-uterine horn fetuses from the squat exercise group were heavier (P < 0.0001) and longer (P < 0.0001) and had a greater placental weight (P = 0.001) than those from control rats. Fetuses from tower-climbing dams were longer (P < 0.0001) and had heavier placentas (P = 0.01) than those from control rats, but fetal weight did not differ from controls. These models of voluntary exercise in the rat may be useful for future studies of the effects of exercise during pregnancy on the developmental origins of health and disease. PMID:21307360

Rosa, Brielle V; Firth, Elwyn C; Blair, Hugh T; Vickers, Mark H; Morel, Patrick C H



Female Specific Appetite Regulation of Daidzein in Rats  

Microsoft Academic Search

Previously, we showed that soy isoflavone daidzein decreased food intake specifically in female rats. Although we have evaluated hypothalamus gene expression of appetite- related neurotransmitter to investigate the mechanism of decreasing food intake by daidzein, we have failed to acquire useful information, because of variation in the meal patterns of individual rats. In the present study, we examined hypothalamus gene



Activity-Based Anorexia In Female Rats  

Microsoft Academic Search

Activity-based anorexia (ABA) in an animal model of anorexia nervosa, in which rats are allowed free access to running wheels but only 2 h food access per day. Rats exposed to this paradigm display symptoms similar to those seen in anorexic women. These include decreased food intake, increased activity, rapid body weight loss, and estrous cycle disruptions. Despite that anorexia

Deann Dixon



Disposition of cefixime in the pregnant and lactating rat. Transfer to the fetus and nursing pup.  


The disposition of cefixime, a potent, third generation, orally active cephalosporin, was characterized in the pregnant and lactating rat. After a single iv dose of 17.8 mg/kg 14C-cefixime to day 18 pregnant rats, the half-life for elimination of radioactivity from both maternal serum and placentas was 6.9 hr. Elimination from fetal plasma and tissues was somewhat longer, 12.5 and 13.7 hr, respectively. However, comparison of areas under the curve indicated that exposure of the fetuses to cefixime was far less than that of placentas. Whole body autoradiography showed the greatest radioactivity in maternal liver, kidney, and intestines. In the lactating rat, steady state plasma concentrations of 14C-cefixime were achieved by continuous ip infusion of 2.54 mg/kg/day via Alza osmotic Mini-pumps from days 10 to 14 postpartum. Plasma concentrations of radioactivity in the dams were, on the average, 70 times greater than in their nursing pups throughout the study. After 102 hr of drug infusion, total radioactivity in the body of the pups, including the stomach and intestinal contents, was 1% of the 14C-cefixime estimated to be in the mother's body at steady state. Overall, these data indicate that exposure of the developing rat fetus and nursing pup to cefixime after maternal drug administration is quantitatively small. PMID:2894941

Halperin-Walega, E; Batra, V K; Tonelli, A P; Barr, A; Yacobi, A


Kindling-induced emotional behavior in male and female rats.  


Modeling fear in animals is a critical approach for identifying the neural mechanisms involved in human disorders such as generalized anxiety and panic. Amygdala kindling has proven useful in this regard because it produces dramatic increases in fearful behavior. The purpose of this experiment was to compare the behavioral effects of kindling in male and female rats. Compared with the sham-stimulated rats, the kindled male and female rats showed similar increases in fearful behavior, with some sex differences in fear-related open-field activity. They also showed decreased immobility in the forced-swim test and increased sucrose consumption. These results suggest that kindling-induced fear is generally similar in male and female rats and that kindling does not appear to induce depression-like behavior. PMID:12802891

Wintink, Amanda J; Young, Nicole A; Davis, Alicia C; Gregus, Andrea; Kalynchuk, Lisa E



Impaired hepatic glycogenolysis related to hyperinsulinemia in newborns from hyperglycemic pregnant rats.  


We have investigated the respective roles of insulin and glucagon in the initiation of hepatic glycogen degradation during the early postnatal period in rats, with special regard on the inhibitory effect of insulin on this process. Pregnant rats were rendered either slightly (8.5 mM) or highly hyperglycemic (22 mM) by infusing glucose during the last week of pregnancy. Fasted, newborn rats were studied from delivery to 16 h postpartum. At birth, newborns from slightly hyperglycemic rats showed higher glycemia and insulinemia and lower plasma glucagonemia compared with controls. Newborns from highly hyperglycemic rats were still more hyperglycemic and exhibited low plasma glucagon concentrations, but they were not hyperinsulinemic. In control newborns, hepatic glycogen breakdown was triggered by 2 h after delivery. By contrast, hyperglycemic-hyperinsulinemic newborns (newborns from slightly hyperglycemic rats) were unable to mobilize liver glycogen before 8-10 h after delivery. In hyperglycemic-normoinsulinemic newborns (newborns from highly hyperglycemic rats), hepatic glycogen concentration significantly started to decline 2 h after delivery and was no longer different from controls at 8 h. Anti-insulin serum injection at delivery promoted a prompt decrease in liver glycogen stores in controls as well as in newborns from slightly hyperglycemic rats. Phosphorylase a/synthase a ratio rose rapidly after delivery in controls and in newborns from highly hyperglycemic rats (maximum 4 h), whereas in newborns from slightly hyperglycemic rats, it rose much more slowly than in the two other groups (maximum 16 h). These data suggest that, in newborns from hyperglycemic mothers, hyperinsulinemia during late fetal and early neonatal life is the main factor preventing postnatal hepatic glycogenolysis. PMID:2284164

Jame, P; Ktorza, A; Bihoreau, M T; Nurjhan, N; Ferré, P; Girard, J; Picon, L



Possible mechanism for accelerated atherogenesis in male versus female rats  

SciTech Connect

Dietary fat and cholesterol enter the circulation as chylomicrons. They are removed from the circulation by attachment to lipoprotein lipase located on the endothelial surfaces. As the result of lipoprotein lipase action, chylomicrons are partially hydrolyzed and then reenter the circulation as remnants, which are rapidly cleared by the liver. We investigated the fate of /sup 3/H-retinol- and /sup 14/C-cholesterol-labeled chylomicrons injected into male and female rats. The disappearance curves of chylomicrons from the circulation were not significantly different in males and females, which suggests that translocation from plasma to endothelium is similar for both sexes. However, in male rats, the dwell time of chylomicrons on the endothelium was significantly prolonged. At 10 and 20 minutes after chylomicron injection, more label was found in the livers of female than male rats. The opposite was true for hearts. Male hearts contained significantly more endothelium-bound chylomicrons when compared with female hearts. This increase in dwell time may allow greater cholesterol deposition in the endothelium of male rats. The more rapid processing of chylomicrons was associated with a 300% greater postheparin lipoprotein lipase in female rats, which suggests a greater enzyme density at chylomicron attachment points on endothelium.

Staprans, I.; Felts, J.M.



Assessment of hepatobiliary function and placental barrier integrity in pregnant rats by combination of bromosulphophthalein and fluorescein isothiocyanate plasma disappearance tests.  

PubMed Central

The permeability of the placental barrier to bromosulphophthalein (BSP) is believed to be very low. Whether this property is shared by other cholephilic organic anions, such as fluorescein isothiocyanate (FITC), is not known. When BSP was injected (140 mumol/kg body wt) into the left jugular vein of non-pregnant or pregnant female rats (at the 21st day of pregnancy), a similar and rapid plasma disappearance was observed during the first few minutes; afterwards, a slower disappearance phase was found. This phase was different in these groups, that is, a longer retention of BSP in the maternal bloodstream of pregnant rats was accompanied by a slower BSP output into bile. It was impossible to demonstrate the presence of BSP in fetal blood or the placenta by colorimetric methods. These results are consistent with the modifications occurring in the hepatic handling of BSP during pregnancy together with a marked impermeability of the placenta to the dye, at least in the mother-to-fetus direction. After intravenous FITC (10 mumol/kg body wt) administration to the mother, the compound was rapidly transferred into both the maternal bile and the fetal blood. Thereafter, FITC refluxed back from the fetal-placental compartment to the maternal blood as soon as the maternal liver reduced its plasma concentrations, which were first higher (approximately threefold) and then similar to those found in fetal blood. The reversible retention of FITC by the fetal-placental compartment accounts for a significant delay in both FITC bile output and plasma disappearance as compared with those observed in non-pregnant rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Villaneuva, G. R.; Sanchez-Abarca, L. I.; Bravo, P.; el-Mir, M. Y.; Marin, J. J.



Differential Effect of Caffeine Consumption on Diverse Brain Areas of Pregnant Rats  

PubMed Central

Background It has previously been shown that during gestation, the mother's brain has an increase in glial fibrillary acidic protein (GFAP)-immunoreactivity (-ir) and a decrease in the mRNA level of A1 adenosine receptor. Little is known about the A2A adenosine receptor in the maternal brain, and whether caffeine consumption throughout gestational period modifies GFAP and adenosine receptor density in specific brain areas. This study was undertaken to investigate the protein density of GFAP and adenosine receptors (A1 and A2A subtypes) in different regions of pregnant rat brain and the possible effect of caffeine on these proteins. Methods For this purpose, we examined the GFAP-, A1- and A2A-ir in the cingulate cortex (Cg2), dentate gyrus (DG), medial preoptic area (mPOA), secondary somatosensory cortex (S2), and striatum (Str) of pregnant Wistar rats (drug-free tap water or water with 1g/L diluted caffeine). Results We show a consistent and highly significant reduction of GFAP-ir in caffeine-treated pregnant rats in most of the areas analyzed. Our data demonstrate that caffeine consumption induces a significant increase of A2A-ir in Str. Concerning A1 receptor, the observed changes are dependent on the region analyzed; this receptor density is increased in Cg2, DG, and mPOA and decreased in the somatosensory cortex and Str. The results were confirmed by Western blotting. Conclusions Our results suggest that chronic caffeine exposure could modify the physiolological situation of gestation by a reorganization of the neural circuits and the adenosine neuromodulator system.

Ballesteros-Yanez, Inmaculada; Castillo, Carlos Alberto; Amo-Salas, Mariano; Albasanz, Jose Luis



Contractile efficacy of various prostaglandins in pregnant rat myometrium pretreated with oxytocin.  


Oxytocin pretreatment of pregnant rat myometrium has been shown to reduce the contractions produced by further administration of oxytocin, as a function of the desensitization phenomenon. It is unclear whether this phenomenon affects the contractions produced by various prostaglandins that are used in the management of postpartum hemorrhage. The objective of this study was to investigate the contractile effects of various prostaglandins after oxytocin pretreatment and to compare their relative efficacies in vitro on pregnant rat myometrial strips. Myometrial samples from 29 pregnant Wistar rats at term were isolated and pretreated with oxytocin (10(-8) mol/L, experimental group) or physiological salt solution (control group) for 1 hour. They were then subjected to dose-response testing with oxytocin (n = 32), PGF2? (n = 16), dinoprostone (n = 14), alprostadil (n = 14), or misoprostol (n = 15) with cumulative increases in the organ bath concentrations from 10(-10) to 10(-5) mol/L. The contractile efficacies of various prostaglandins and oxytocin during the dose response were analyzed using mixed linear modeling and compared between the groups. There was no significant difference in the amplitude, frequency, motility index (amplitude × frequency), or area under the curve of all prostaglandins between the groups pretreated with oxytocin and the control group. However, there was a significant decrease in the frequency (P = .02) and motility index (P = .05) in the dose-response curves of oxytocin in the groups pretreated with oxytocin compared with the control groups. Overall, oxytocin produced superior contractions compared with all other prostaglandins, while dinoprostone and misoprostol produced the weakest contractions. The uterotonic effects of various prostaglandins are not affected by oxytocin desensitization; and despite desensitization, oxytocin provides superior contractions compared with the prostaglandins. PMID:22539357

Balki, Mrinalini; Kanwal, Nikki; Erik-Soussi, Magda; Kingdom, John; Carvalho, Jose C A



Early life stress induces renal dysfunction in adult male rats but not female rats.  


Maternal separation (MatSep) is a model of behavioral stress during early life. We reported that MatSep exacerbates ANG II-induced hypertension in adult male rats. The aims of this study were to determine whether exposure to MatSep in female rats sensitizes blood pressure to ANG II infusion similar to male MatSep rats and to elucidate renal mechanisms involved in the response in MatSep rats. Wistar Kyoto (WKY) pups were exposed to MatSep 3 h/day from days 2 to 14, while control rats remained with their mothers. ANG II-induced mean arterial pressure (MAP; telemetry) was enhanced in female MatSep rats compared with control female rats but delayed compared with male MatSep rats. Creatinine clearance (Ccr) was reduced in male MatSep rats compared with control rats at baseline and after ANG II infusion. ANG II infusion significantly increased T cells in the renal cortex and greater histological damage in the interstitial arteries of male MatSep rats compared with control male rats. Plasma testosterone was greater and estradiol was lower in male MatSep rats compared with control rats with ANG II infusion. ANG II infusion failed to increase blood pressure in orchidectomized male MatSep and control rats. Female MatSep and control rats had similar Ccr, histological renal analysis, and sex hormones at baseline and after ANG II infusion. These data indicate that during ANG II-induced hypertension, MatSep sensitizes the renal phenotype in male but not female rats. PMID:23174859

Loria, Analia S; Yamamoto, Tatsuo; Pollock, David M; Pollock, Jennifer S



Antiplatelet drugs and the generalized Shwartzman reaction in the pregnant rat.  


Several antiplatelet drugs (aspirin, sulfinpyrazone, hydroxychloroquine, dipyridamole, BL-3459, pyridinolcarbamate) were assayed for their ability to prevent the generalized Shwartzman reaction initiated by endotoxin in the pregnant rat, and compared to glucocorticoids (dexamethasone, hydrocortisone). The drugs were administered in a single large dose a few hours before provocation of the reaction. In opposition to glucocorticoids and beside BL-3459 which interfere with other mechanisms involved in the phenomenon, the tested inhibitors of platelet aggregation were found incapable of preventing or reducing the severity of the Shwartzman reaction. PMID:490317

Latour, J G; Groulx, C



Effect of physical training on metabolic responses of pregnant rats submitted to swimming under thermal stress  

PubMed Central

BACKGROUND: The aim of this study is to assess the effect of pre-pregnancy physical training on metabolic responses and its effects on offspring. METHODS: Three groups of rats (n = 7 in each group): sedentary pregnant rats (PS), exercised during pregnancy (PE) and pregnant rats trained before and during pregnancy (PT) were compared. They were separated into three subgroups regarding water temperature: 28°C, 35°C or 39°C. Plasma triglycerides and glucose levels, weight gain during pregnancy and rectal temperature pre and post exercise (swim), as well as the offspring size and weight were analysed. RESULTS: Rectal temperature post exercise was lower than pre exercise at 28°C and 35°C, and higher at 39°C. Weight gain was lower at 39°C for the PT group and at 35°C for the PT and PE groups compared to the PS group. Plasma glucose, at 28°C and 39°C for PS and PE groups, was higher than those obtained at 35°C, while triglycerides were lower. For trained rats, plasma glucose and triglycerides were similar at all water temperatures. Trained rats presented lower triglyceride values at 35°C, and higher triglyceride values at 39°C compared to PS group. Glucose presented inverse results. None of the groups presented fetal reabsorption. However, in the PS group, the offspring presented lower weight gain at 28°C than at 35°C and 39°C. CONCLUSIONS: These results suggest that pre-pregnancy physical training induces steady values of triglycerides and glucose during exercise at all water temperatures.

Lazo-Osorio, Rodrigo Alexis; Pereira, Rafael; Christofani, Junia Scarlatelli; Russo, Adriana Kowalesky; Machado, Marco; Ribeiro, Wellington; da Cruz Picarro, Ivan



2,3,7,8-Tetrachlorodibenzo-p-dioxin in pregnant Long Evans rats: disposition to maternal and embryo/fetal tissues.  


Prenatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) interferes with fetal development at doses lower than those causing overt toxicity in adult animals. In a multigeneration study (Murray et al., 1979), female rats that were administered 0.01 microgram TCDD/kg/day in their diet did not experience reduced fertility; however, reduced fertility was seen in the F1 and F2 generations. Exposure to TCDD during development produces alterations in the reproductive system of the developing pups, such as delayed puberty and reduced sperm counts in males (Mably et al., 1992a; Gray et al., 1995) and malformations in the external genitalia of females (Gray and Ostby, 1995). Therefore, the objectives of this study were to determine maternal and fetal tissue concentrations of TCDD that are associated with the adverse reproductive effects seen by Gray and co-workers. Pregnant Long Evans rats received a single oral dose of 1.15 micrograms [3H]TCDD/kg on Gestation Day (GD) 8 and maternal as well as fetal tissue concentrations of TCDD were measured on GD9, GD16, and GD21. On GD9, the highest level of TCDD localized in the maternal liver (25.1% dose). In addition, the amount reaching all the embryos on GD9 was 0.01% of the administered dose, which resulted in a concentration of 0.02% dose/g. The amount of TCDD reaching the fetal compartment (fetuses + placentas) increased to 0.12% dose/tissue on GD16 and 0.71% by GD21. The concentration of TCDD within the fetal compartment (0.01% dose/g) on GD16 was comparable to that found in the maternal blood and spleen. Concentrations of TCDD in a single embryo/fetus were 39.6, 18.1, and 22.1 pg/g on GD9, GD16, and GD21, respectively. Estimates of hepatic half-life of elimination in pregnant rats suggested that TCDD may be eliminated faster in pregnant LE rats. Therefore, measurements of biliary elimination were made in pregnant and nonpregnant LE rats to compare rates of metabolism; however, biliary elimination of TCDD is not affected by pregnancy. In conclusion, this dose administered during a critical period of organogenesis causes adverse effects on the developing reproductive system of rodents. This dose produced a body burden of 22.1 pg TCDD/g within a single fetus on GD21. This indicates that low-level TCDD exposure during the perinatal stage of life can produce adverse effects within the developing pups. PMID:9848119

Hurst, C H; Abbott, B D; DeVito, M J; Birnbaum, L S



Gonadal hormones and picrotoxin-induced convulsions in male and female rats  

Microsoft Academic Search

The sensitivity to the GABA-blocking agent picrotoxin was studied in young and adult male and female rats, in rats treated with gonadal hormones and in gonadectomized male and female rats. Picrotoxin was equipotent in producing convulsions in male and female 20-day-old rats. Adult females tended to be more, while adult males were considerably less sensitive to picrotoxin than young rats.

Danka Peri?i?; Hari Manev; Maja Bujas



Blood burden of di(2-ethylhexyl) phthalate and its primary metabolite mono(2-ethylhexyl) phthalate in pregnant and nonpregnant rats and marmosets  

Microsoft Academic Search

A comparison of the dose-dependent blood burden of di(2-ethylhexyl) phthalate (DEHP) and mono(2-ethylhexyl) phthalate (MEHP) in pregnant and nonpregnant rats and marmosets is presented. Sprague–Dawley rats and marmosets were treated orally with 30 or 500 mg DEHP\\/kg per day, nonpregnant animals on 7 (rats) and 29 (marmosets) consecutive days, pregnant animals on gestation days 14–19 (rats) and 96–124 (marmosets). In

Winfried Kessler; Wanwiwa Numtip; Konstanze Grote; György A. Csanády; Ibrahim Chahoud; Johannes G. Filser



Hepatic bile acids and bile acid-related gene expression in pregnant and lactating rats.  


Background. Significant physiological changes occur during pregnancy and lactation. Intrahepatic cholestasis of pregnancy (ICP) is a liver disease closely related to disruption of bile acid homeostasis. The objective of this study was to examine the regulation of bile acid synthesis and transport in normal pregnant and lactating rats. Materials and Methods. Livers from timed pregnant SD rats were collected on gestational days (GD) 10, 14 and 19, and postnatal days (PND) 1, 7, 14 and 21. Total bile acids were determined by the enzymatic method, total RNA was isolated and subjected to real time RT-PCR analysis. Liver protein was extracted for western-blot analysis. Results. Under physiological conditions hepatic bile acids were not elevated during pregnancy but increased during lactation in rats. Bile acid synthesis rate-limiting enzyme Cyp7a1 was unchanged on gestational days, but increased on PND14 and 21 at mRNA and protein levels. Expression of Cyp8b1, Cyp27a1 and Cyp7b1 was also higher during lactation. The mRNA levels of small heterodimer partner (SHP) and protein levels of farnesoid X receptor (FXR) were increased during pregnancy and lactation. Bile acid transporters Ntcp, Bsep, Mrp3 and Mrp4 were lower at gestation, but increased during lactation. Hepatic Oatp transporters were decreased during pregnancy and lactation. Conclusion. Hepatic bile acid homeostasis is maintained during normal pregnancy in rats, probably through the FXR-SHP regulation. The expression of bile acid synthesis genes and liver bile acid accumulation were increased during lactation, together with increased expression of bile acid efflux transporter Bsep, Mrp3 and Mrp4. PMID:24010021

Zhu, Qiong N; Xie, Hong M; Zhang, Dan; Liu, Jie; Lu, Yuan F



Teratogenicity and metabolism of water-soluble forms of vitamin A in the pregnant rat  

SciTech Connect

Retinoyl {beta}-glucuronide, unlike retinoic acid, has been shown to be non-teratogenic when administered orally, even in large doses, to pregnant rats. The degree to which water-solubility is associated with low teratogenicity is not known. Other water-soluble forms of vitamin A have now been synthesized in our laboratory and are being evaluated for teratogenicity. New water-soluble forms of vitamin A were administered orally to pregnant Sprague-Dawley rats in a single dose of 0.35 mmole/kg bw on day 8 of gestation. On day 19, the dams were sacrificed and the litters were examined. Control animals received either vehicle only or an equivalent dose of all-trans retinoic acid. Maternal and fetal tissues were taken and analyzed by HPLC for vitamin A metabolites. In another experiment, a large single oral dose of the radiolabelled water-soluble compound was administered on day 10. At either 30 minutes or 1 hour after the dose, dams were sacrificed and the embryos analyzed both for radioactivity and for specific metabolites. In contrast to retinoyl {beta}-glucuronide, retinoyl {beta}-glucose is highly teratogenic under identical conditions. Thus, water-solubility does not seem to be the determining factor in the teratogenicity of retinoic acid conjugates.

Gunning, D.B.; Barua, A.B.; Olson, J.A. (Iowa State Univ., Ames (United States))



Elimination kinetics of domoic acid from the brain and cerebrospinal fluid of the pregnant rat.  


Domoic acid (DA) causes neurological effects in multiple species upon exposure, including status epilepticus in pregnant sea lions and an epileptic disease state that commonly develops in juveniles. This study aims to define brain toxicokinetic parameters in the pregnant rat in the larger context of maternal-fetal toxin transfer. Specifically, Sprague-Dawley rats were exposed to a low observable effect level of 1.0 mg DA/kg intravenously at gestational day 20, and plasma, brain, and cerebrospinal fluid (CSF) samples were taken at discrete time points over 24 h. Domoic acid concentrations were determined by a tandem LC/MS method recently optimized for brain tissue and CSF. Data showed that 6.6% of plasma DA reached the brain, 5.3% reached the CSF, and DA levels were nearly identical in both brain and CSF for 12 h, remaining above the threshold to activate isolated hippocampal neurons for 2 h. The calculated terminal half-life of CSF was 4 h, consistent with the time for complete CSF regeneration, suggesting that CSF acts as a mechanism to clear DA from the brain. PMID:23134453

Maucher Fuquay, Jennifer; Muha, Noah; Wang, Zhihong; Ramsdell, John S



Evaluation of Bauhinia monandra aqueous and ethanol extracts in pregnant rats.  


Bauhinia monandra Kurz. (Fabaceae: Caesalpinioideae) is a plant widely employed in Brazilian folk medicine for hypoglycemia. However, little is known about the effect of maternal exposure to this plant on fetal development. The aqueous and ethanol extracts obtained from B. monandra dried leaves were administered to pregnant Wistar rats throughout gestation (day 1 to day 20) at 1,400 or 7,000 mg/kg/day (n = 6/group). Maternal toxicity was not observed in the dams of both groups, and was evaluated by observing body weight, water and food intake during treatment, by measuring serum biochemical levels of creatinine, urea, AST and ALT, and by studying the histopathology of liver, kidney, pancreas, spleen and uterus at the end of treatment (gestation day 20). Both extracts and doses did not impair reproductive performance or delay fetal development, measured by observing implantations and reabsorptions in the uterus, by counting the number of corpora lutea in ovaries, by recording the litter weight and number of live and dead fetuses and by analyzing possible skeleton and viscera malformations in the fetuses. Also, the aqueous extract promoted decreased post-implantation loss when compared to the control group. The aqueous and ethanol extracts from B. monandra dried leaves (1,400 or 7,000 mg/kg/day) did not cause maternal or fetal toxicities and the aqueous extract promoted increased implantation and decreased post-implantation loss in the pregnant rats. PMID:20645777

Mendes, Caio C; Marinho, Ciro M F; Moreira-Junior, Valderes F; Queiroz, Fernando M; Dantas, Gláucia L S; Macedo, Márcia F S; Oliveira, Cláudia N; Schwarz, Aline



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.



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.



Sleep homeostasis in the female rat during the estrous cycle  

Microsoft Academic Search

To investigate whether sleep homeostasis in the female rat is modulated by the estrous cycle, the vigilance states, EEG power spectra and cortical temperature (TCRT) were assessed on the basis of 4-day continuous recordings. A regulatory response was elicited by 6-h sleep deprivation (SD) during the proestrous (PRO) and the estrous (EST) day and compared to the baseline recordings. The

Barbara Schwierin; Alexander A. Borbély; Irene Tobler



Ovarian hormones modulate 'compulsive' lever-pressing in female rats.  


Life events related to the female hormonal cycle may trigger the onset of obsessive-compulsive disorder (OCD) or exacerbate symptoms in women already suffering from it. These observations suggest a possible role for ovarian hormones in the course of this disorder. Yet, the mechanisms that may subserve the modulatory effect of ovarian hormones are currently unknown. The aim of the present study was therefore to test the role of ovarian hormones in the signal attenuation rat model of OCD. Experiment 1 compared the behavior of pre-pubertal and adult male and female rats in the model, and found no age and sex differences in compulsive responding. Experiment 2 found that compulsive responding fluctuates along the estrous cycle, being highest during late diestrous and lowest during estrous. Acute administration of estradiol to pre-pubertal female rats was found to attenuate compulsive behavior (Experiment 3), and withdrawal from chronic administration of estradiol was shown to increase this behavior (Experiment 4). These findings extend the use of the signal attenuation model of OCD to female rats, and by demonstrating that the model is sensitive to the levels of ovarian hormones, provide the basis for using the model to study the role of ovarian hormones in OCD. In addition, the present findings support the hypothesis that the increased risk of onset and exacerbation of OCD in women post-partum may be a result of the decrease in the level of estradiol, which was elevated during pregnancy. PMID:18996389

Flaisher-Grinberg, Shlomit; Albelda, Noa; Gitter, Liron; Weltman, Keren; Arad, Michal; Joel, Daphna



[Understanding microcapillary angioma, observations in pregnant patients and in females treated with hormonal contraceptives].  


We report on histological findings in 3 female patients, who developed microcapillary angiomas either during pregnancy or upon changing the oral contraceptive. These hemangiomas consisted of small, well-differentiated vessels located in the reticular dermis only and did not show any intra- or extravascular cell proliferation. We discuss the possible etiological factors of these microcapillary angiomas as well as the question of their correlation with pregnancy or hormonal contraceptives. PMID:2534452

Bantel, E; Grosshans, E; Ortonne, J P



A boundary-representation method for designing whole-body radiation dosimetry models: pregnant females at the ends of three gestational periods—RPI-P3, -P6 and -P9  

Microsoft Academic Search

Fetuses are extremely radiosensitive and the protection of pregnant females against ionizing radiation is of particular interest in many health and medical physics applications. Existing models of pregnant females relied on simplified anatomical shapes or partial-body images of low resolutions. This paper reviews two general types of solid geometry modeling: constructive solid geometry (CSG) and boundary representation (BREP). It presents

X George Xu; Valery Taranenko; Juying Zhang; Chengyu Shi



A boundary-representation method for designing whole-body radiation dosimetry models: pregnant females at the ends of three gestational periods---RPI-P3, -P6 and -P9  

Microsoft Academic Search

Fetuses are extremely radiosensitive and the protection of pregnant females against ionizing radiation is of particular interest in many health and medical physics applications. Existing models of pregnant females relied on simplified anatomical shapes or partial-body images of low resolutions. This paper reviews two general types of solid geometry modeling: constructive solid geometry (CSG) and boundary representation (BREP). It presents

X. George Xu; Valery Taranenko; Juying Zhang; Chengyu Shi



Vaginal and endocervical microorganisms in symptomatic and asymptomatic non-pregnant females: risk factors and rates of occurrence.  


Physiological or non-physiological factors may affect the vaginal flora. The occurrence of genital microorganisms in non-pregnant females of all ages was studied, as were the risk factors associated with each microorganism. A retrospective analysis of vaginal and endocervical cultures and wet smears from 27,172 non-pregnant women, between 1996 to 2005, was performed taking into consideration clinical and socio-demographic characteristics. No microorganisms were observed in 55.7% of the individuals studied and 44.3% had positive cultures. There was no microbiological aetiology in 49% of women with genital symptoms. Poor hygiene, chemical irritants, sexual behaviour, vaginal blood, birth control type, and/or the lack of an oestrogen effect may have caused the symptoms. The highest occurrence of Gram-negative bacteria (p<0.01), mainly Escherichia coli, was observed in prepubescent girls. The highest occurrence of Candida species (p<0.01) was in women of childbearing age, and of Gram-positive bacteria (p<0.01) in menopausal women. Adolescents, particularly asymptomatic girls, carried more frequently Ureaplasma urealyticum and Chlamydia trachomatis (p<0.01). Hormonal contraception and consistent condom use was protective against bacterial vaginosis and U. urealyticum colonization. Users of intrauterine devices had an increased risk of bacterial vaginosis or of contracting U. urealyticum, Mycoplasma hominis and Candida species. Genital complaints were an independent indicator of Candida species, Gram-negative and Gram-positive bacteria, Trichomonas vaginalis and bacterial vaginosis.Chlamydia trachomatis infections were often asymptomatic. It is concluded that the hormonal milieu and non-physiological factors are major determinants of the vaginal flora. If diagnosis of genital infections is based on symptoms alone and not on culture results, it may be erroneous. Sexual abuse should be investigated when a child presents with a sexually transmitted disease. PMID:19558525

Tibaldi, C; Cappello, N; Latino, M A; Masuelli, G; Marini, S; Benedetto, C



Effects of marginal iron overload on iron homeostasis and immune function in alveolar macrophages isolated from pregnant and normal rats  

Microsoft Academic Search

The effects of changes in macrophage iron status, induced by single or multiple iron injections, iron depletion or pregnancy,\\u000a on both immune function and mRNA expression of genes involved in iron influx and egress have been evaluated. Macrophages isolated\\u000a from iron deficient rats, or pregnant rats at day 21 of gestation, either supplemented with a single dose of iron dextran,

Roberta J. Ward; Stephanie Wilmet; Rachida Legssyer; Daniel Leroy; Louise Toussaint; Robert R. Crichton; Christophe Pierreux; Louis Hue; Jacques Piette; Surjit Kaila Srai; Nita Solanky; Dominique Klein; Karl Summer



The effects of nitric oxide on the contractility of isolated uterine and aortic rings from pregnant rats  

Microsoft Academic Search

OBJECTIVE: The object was to compare the effects of nitric oxide on isolated uterus and aorta of pregnant rats.STUDY DESIGN: Rings of uterus and thoracic aorta without endothelium from Sprague-Dawley rats at mid and late gestation were used for isometric tension recording. The concentration-response curve for diethyl-amine\\/nitric oxide was studied in the presence or absence of oxyhemoglobin (10–5 mol\\/L), or

Toshiaki Okawa; Ashu S. Syal; Yuri P. Vedernikov; George R. Saade; Kristof Chwalisz; Robert E. Garfield



Prolonged inhibition of nitric oxide synthesis in pregnant rats: effects on blood pressure, fetal growth and litter size  

Microsoft Academic Search

Methods: In order to investigate the effect of chronic inhibition of nitric oxide synthesis along preg- nancy, pregnant rats were given drinking water alone (control group) or drinking water containing nonselective nitric oxide synthase inhibitor N x -nitro-L-arginine me- thyl ester (L-NAME; 15 mg\\/day\\/rat equivalent to 50 mg\\/ kg\\/day; treated group), from postmating days 1 to 18 of pregnancy. On

Lina Fernández Celadilla; Maite Carbajo Rueda; Manuel Muñoz Rodríguez



Bacterial infection and endotoxin in female reproductive tract in rats: correlation with the developmental status of preimplantation embryos.  


During mammalian preimplantation development, a substantial numbers of embryos are believed to be lost for reasons that are unclear. Using female rats, we investigated whether the developmental status of embryos is influenced by bacterial infection and endotoxin in the reproductive tract. From the vagina of cycling rats (n = 11), 21 bacterial isolates were identified; they were Streptococcus faecalis (S. faecalis; 38%), Escherichia coli (E. coli; 19%), Acinetobactor calcoaceticus (A. calcoaceticus; 14%), and coagulase negative staphylococcus (14%), Micrococcus sp. (5%), Bacillus subtilis (B. subtilis; 5%) and Proteus vulgaris (P. vulgaris; 5%). From the vagina of day 4 pregnant rats (n = 12), 26 isolates were identified; they were S. faecalis (23%), A. calcoaceticus (23%), E. coli (15%), Micrococcus sp. (15%), B. subtilis (8%), P. vulgaris (4%), Staphylococcus aureus (4%), beta-hemolytic streptococcus (4%) and Pseudomonas aeruginosa (4%). Gram negative bacteria found in the vagina of cycling and day 4 pregnant rats were 38% and 46%, respectively. In both, bacterial load was 10(3)-10(5) colony forming units and there was no association with the abnormality of the recovered embryos. However, in two day 4 pregnant animals, pathogenic bacteria (Staphylococcus aureus and beta-hemolytic streptococcus) were isolated and embryos recovered from them were degenerated and deformed. The vagina of day 9 pregnant animals (n = 7) were, however, sterile. Consistently, in all animals, the upper reproductive tract (uterus and oviduct) was devoid of any bacteria and no anaerobic bacteria were isolated from any part of the tract. The levels of endotoxin in the vagina of cycling and day 4 pregnant rats were 1.35 +/- 0.1 and 1.17 +/- 0.1 endotoxin units (EU), respectively. It was undetectable in the oviduct and uterus of all animals (n = 5) except one which showed high levels of endotoxin in uterus (4.5 EU) and oviduct (2.2 EU) and the animal also produced degenerated and deformed embryos. These results indicate that common bacterial flora of vagina may not affect embryo development and the presence of pathogenic bacteria in the vagina and/or endotoxin in reproductive tract could be detrimental to viability of gametes and preimplantation embryos in rats. PMID:9854425

Ain, R; Rao, J; Peter, A T; Vijaykumar, B R; Sridhar, H; Satish, K S; Seshagiri, P B



Effects of sodium fluoride on reproductive function in female rats.  


The aim of this study was to investigate the effects of sodium fluoride (NaF) on female reproductive function and examine the morphology of the ovaries and uteri of rats exposed to NaF. Eighty female Sprague-Dawley (SD) rats were divided randomly into four groups of 20: one control group and three NaF treated groups. The three NaF treated groups received 100, 150, and 200 ppm, respectively, of NaF for 6 months via their drinking water, while the control group (GC) received distilled water. The levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (T), progesterone (P) and estradiol (E2) were measured using an enzyme-linked immunosorbent assay. Pathomorphological evaluation of the uteri and ovaries was conducted after staining with hematoxylin-eosin and immunohistochemistry. The rate of successful pregnancy in the NaF-treated groups declined in a dose-dependent manner. The concentration of reproductive hormones was significantly lower in the three NaF-treated groups, and the endometrium was damaged. The maturation of follicles was inhibited. In addition, the total number of follicles of all types was significantly lower in the NaF-treated groups. These results suggest that female reproductive function is inhibited by NaF and that exposure to NaF causes ovarian and uterine structural damage. NaF may thus significantly reduce the fertility of female rats. PMID:23459146

Zhou, Yongjiang; Zhang, Hailing; He, Junlin; Chen, Xuemei; Ding, Yubing; Wang, Yingxiong; Liu, Xueqing



Factors influencing fluoxetine-induced sexual dysfunction in female rats.  


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



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.



Olive oil consumption during pregnancy and lactation in rats influences mammary cancer development in female offspring.  


This study examined the effects of variety and quantity of dietary fat consumed by rats during pregnancy and lactation on female offspring's response to chemically induced mammary cancer. Groups of six female rats were fed diets containing 7% corn oil (7-CO), 15% CO (15-CO), 7% olive oil (7-OO), or 15% OO (15-OO) for 5 wk prior to, and during, pregnancy and lactation. Female offspring (n = 15 per group) were fed a 7-CO diet, and mammary cancer was induced with 7,12-dimethylbenz[a]anthracene (DMBA). Three months following cancer induction tumor incidence and size were recorded, and markers of apoptosis, serum estrogen concentrations, and hepatic phase II enzymes were measured. Tumor incidence was 47% in offspring born to mothers fed the 7-OO diet, rose to 67% in 7-CO and 15-OO offspring, and reached 86% in 15-CO. A trend toward smaller tumors was observed in the 7-OO group, and offspring of mothers fed high-fat diets had significantly more tumors. Estradiol levels at the end of lactation were significantly lower in mothers fed 7-OO but were similar in all groups of offspring. In tumor tissue, Bcl-2 expression was highest in the 15-CO offspring, and Bak expression was significantly higher in rats exposed to OO. A distinct trend toward increased caspase-3 expression (20 kDa) was observed in the 7-OO offspring, and both low-fat diets significantly elevated caspase activity. In healthy mammary tissue, rats exposed to low-fat diets had significantly higher caspase-3 (32-kDa) levels, and caspase-3 activity was significantly higher in the healthy tissue from both OO groups. Hepatic quinone reductase activity was significantly lower in offspring of mothers fed the low-fat diets. These results indicate that perinatal exposure to OO may have a protective effect against future development of mammary cancer in female offspring, whereas high-fat diets fed to pregnant and lactating rats, in particular CO, may be deleterious. PMID:12925305

Stark, Aliza H; Kossoy, George; Zusman, Itshak; Yarden, Ganit; Madar, Zecharia



Dietary restriction and nicotine can reduce anxiety in female rats.  


Anxiety may play a role in the initiation of smoking and there is evidence to suggest that sex and age may predetermine responses to nicotine. At present, the greatest increase in smoking is in women and it is often accompanied by dieting. The purpose of the present study was to investigate how the impact of dietary restriction might modify the effects of nicotine in female adult and adolescent rats. The effects of nicotine in the elevated plus-maze test of anxiety were compared in free-feeding animals and those subjected to dietary restriction that reduced body weight to 85% of free-feeding weight. In nondeprived adult females, nicotine (0.05-0.5 mg/kg, s.c.) reduced the percentage of time spent on the open arms, indicating anxiogenic effects. However, the effects of nicotine were dramatically changed in food-restricted adult females and 0.05 mg/kg had a striking anxiolytic effect. No significant effects of nicotine were found in the adolescent female rats, suggesting a role of circulating sex hormones in modulating nicotine's effects on anxiety. However, in the adolescent females, dietary restriction significantly increased the percentages of time spent and entries onto the open arms, without changing closed arm entries, indicating an anxiolytic effect. These results raise the important possibility that, in prepubertal girls, dietary restriction may have anxiolytic effects and this might contribute to the onset of anorexia. Circulating female hormones reduce this effect, but in adult females the combination of dietary restriction and nicotine may have important anxiolytic effects that impact on the initiation of regular smoking. PMID:12700683

Genn, Rachel F; Tucci, Sonia; Edwards, Jessica E; File, Sandra E



Behavioral sensitization to nicotine in female and male rats  

Microsoft Academic Search

Behavioral sensitization to nicotine has been studied in both male and female rats, but studies up to now have been difficult\\u000a to compare due to different experimental conditions. Including both sexes in scientific research is of great importance since\\u000a clinical data indicate gender differences both in response to nicotine and in ability for smoking cessation. The aim of the\\u000a present

Mia Ericson; Gunilla Norrsjö; Anders I. Svensson



Relationships between postweaning residual feed intake in heifers and forage use, body composition, feeding behavior, physical activity, and heart rate of pregnant beef females.  


The objectives of this study were to determine if residual feed intake (RFI) classification of beef heifers affected efficiency of forage utilization, body composition, feeding behavior, heart rate, and physical activity of pregnant females. Residual feed intake was measured in growing Bonsmara heifers for 2 yr (n = 62 and 53/yr), and heifers with the lowest (n = 12/yr) and highest (n = 12/yr) RFI were retained for breeding. Of the 48 heifers identified as having divergent RFI, 19 second-parity and 23 first-parity females were used in the subsequent pregnant-female trial. Pregnant females were fed a chopped hay diet (ME = 2.11 Mcal kg(-1) DM) in separate pens equipped with GrowSafe bunks to measure individual intake and feeding behavior. Body weights were measured at 7-d intervals and BCS and ultrasound measurements of 12th-rib fat depth, rump fat depth, and LM area obtained on d 0 and 77. Heart rate and physical activity were measured for 7 consecutive d. First-parity females had lower (P < 0.05) initial BW, BW gain, and initial hip height and tended (P = 0.07) to have lower DMI compared to second-parity females. Females with low RFI as heifers consumed 17% less (P < 0.01) forage compared to females with high RFI as heifers but maintained the same BW, BW gain, and body composition. Likewise, RFI classification did not affect calving date. An interaction (P = 0.04) between heifer RFI classification and parity was found for calf birth weight. Calves from first-parity low-RFI females were lighter at birth (P < 0.01) than calves from high-RFI females, but RFI classification did not affect BW of calves born to second-parity females. Residual feed intake classification did not affect bunk visit frequency, but low-RFI females spent 26% less time (P < 0.01) at the bunk compared to high-RFI females. First-parity females had more (P < 0.05) daily step counts and greater lying-bout frequencies compared to second-parity females, but physical activity was not affected by RFI classification. Heart rates of females classified as low RFI were 7% lower (P = 0.03) compared to high-RFI females. Heifer postweaning RFI but not G:F or residual gain were positively correlated with forage intake (r = 0.38) and RFI (r = 0.42) of pregnant females. Results indicate that heifers identified as having low postweaning RFI have greater efficiency of forage utilization as pregnant females, with minimal impacts on growth, body composition, calving date, and calf birth BW, compared to their high-RFI counterparts. PMID:23989881

Hafla, A N; Carstens, G E; Forbes, T D A; Tedeschi, L O; Bailey, J C; Walter, J T; Johnson, J R



Effects of genistein on gonadotropic cells in immature female rats.  


The effects of genistein on pituitary gonadotropic cells of immature female rats were examined and compared to actions of the synthetic estrogen, 17?-ethynylestradiol. Immature female rats received 50mg/kg/bw of genistein in dimethylsulfoxide (DMSO) subcutaneously (s.c.) daily for 3 days at 18, 19 and 20 days of age. A second group was injected with 1?g/kg of 17?-ethynylestradiol in olive oil in the same schedule. The genistein control group received DMSO only, while 17?-ethynylestradiol controls were given sterile olive oil only. Changes in cell number per mm(2), cell volume and volume density of follicle-stimulating (FSH) and luteinizing (LH) immunolabeled cells were evaluated by morphometry and stereology. Genistein induced significant increases in the number of FSH cells (by 21%) and LH cells (by 20%) per mm(2) compared to corresponding controls. Volumes of FSH and LH cells were significantly increased by 19.7% and 20% and their volume densities by 20% and 20.2%, respectively. Estradiol markedly affected gonadotropes in the same manner, but to a greater extent. It can be concluded that genistein acted as an estrogenic agonist in the pituitaries of immature female rats, and as such, stimulated gonadotropic cells. PMID:21703666

Medigovi?, Ivana; Manojlovi?-Stojanoski, Milica; Trifunovi?, Svetlana; Risti?, Nataša; Miloševi?, Verica; Ziki?, Dragan; Nestorovi?, Nataša



A low-affinity estrogen-binding site in pregnant rat uteri: analysis and partial purification.  


We have identified a low-affinity (type II) estrogen-binding site (EBS) that is expressed at high levels during pregnancy in rat uteri. Although this activity was detectable in nonpregnant rat uteri, it was present in amounts (0.094 pmol/g of uteri) that were severalfold lower than the high-affinity type I estrogen receptor (0.57 pmol/g of uteri). During pregnancy, at 19-20 days of gestation, the low-affinity type II EBS became the major (> or = 88%) estrogen-binding site in rat uteri. The increase in the level of low-affinity EBS (7.9 pmol/g) in uteri was approximately 85-fold with an approximately 20-fold increase in the specific activity (0.39 pmol/mg) of this form, whereas the high-affinity form remained relatively unchanged. We report here a method of purification of type II EBS from pregnant rat uteri and present an analysis of its DNA and steroid-binding properties. Estradiol-binding studies and Scatchard analysis showed that the type II EBS had an apparent estradiol-binding affinity of > or = 24 nM. Gel filtration and SDS/PAGE analysis indicated that the type II EBS was a monomeric 73-kDa protein. The estradiol binding remained apparently uninhibited in the presence of a large excess of tamoxifen, nafoxidine, or dihydrotestosterone. Estradiol, diethylstilbestrol, and quercitin (a type II EBS-specific inhibitor) competed efficiently. The purified low-affinity EBS did not have sequence-specific DNA-binding activity with the estrogen-responsive element, which indicated that it differs in function from the type I estrogen receptor. PMID:7526397

Gray, W G; Biswas, E E; Bashirelahi, N; Biswas, S B



Increased renal phosphodiesterase-5 activity mediates the blunted natriuretic response to a nitric oxide donor in the pregnant rat  

PubMed Central

Pregnancy is characterized by plasma volume expansion and renal sodium retention with loss of natriuretic response to atrial natriuretic peptide due to increased medullary phosphodiesterase-5 (PDE5). Here, we determined whether natriuretic responses to nitric oxide (NO) are also blunted in pregnancy due to increased PDE5. Anesthetized 16-day pregnant and virgin rats were studied at baseline and during intrarenal infusion of the NO donor spermine NONOate (2.5 nmol/min), the PDE5 inhibitor sildenafil (SILD; 0.5 ?g/min), or a combination. The right (noninfused) kidney served as a control. Intrarenal NONOate had no effect on mean arterial pressure (MAP); however, SILD reduced MAP in virgin rats, and the combination of NONOate+SILD reduced MAP in both virgin and pregnant rats. Neither NONOate nor SILD altered glomerular filtration rate. NONOate and SILD each stimulated sodium excretion (UNaV) and fractional excretion of sodium (FENa) in virgin rats, but the combination did not result in an additional natriuretic response. However, NONOate infusion did not increase UNaV or FENa in pregnant rats, but the natriuretic response to NONOate was restored with SILD, and SILD alone produced a natriuresis during pregnancy. Sodium nitroprusside (10?4 mol/l)-stimulated cGMP accumulation from inner medullary collecting duct cells was blunted in cells from pregnant vs. virgin or postpartum rats and was restored by treatment with the PDE5 inhibitor DMPPO (10?7 mol/l). Therefore, increased intrarenal PDE5 mediates the blunted natriuretic response to NO, and loss of responsiveness to the cGMP-dependent, natriuretic agents may contribute to volume expansion during pregnancy.

Ni, Xi-Ping; Humphreys, Michael H.; Baylis, Chris



Acute toxicological effects of ingested tooth whiteners in female rats.  


Tooth whiteners are considered as cosmetic agents to be used for bleaching teeth. Since tooth whitener may be swallowed during the whitening procedure, studies were conducted to determine whether ingestion of tooth whitener containing carbamide peroxide resulted in toxic effects. Adult female rats were used, and vaginal smears were examined daily to determine whether the animals were ovulating. Following an overnight fast, a single bolus of a commercial tooth whitener (5 g of tooth whitener/kg fasting body weight) was administered by gavage. Control rats received de-ionized water. After 2 h, mean respirations per min of animals receiving the tooth whitener Quik Start (contains 35% carbamide peroxide) decreased from 169 to 55, and body temperature decreased from 38.4 to 34 degrees C. Other distress signs included: labored breathing, loss of righting reflex, partial eye closure, bloody urine, and incontinence. Three of 22 animals (3/22) died within 48 h, of gastric hemorrhaging. Eight/10 rats stopped ovulating. At necropsy 2 weeks post-dosing, 10/19 animals had grossly bloated stomachs, and mucosal necrosis was observed histologically in 3. Animals receiving White & Brite or Nu-Smile (containing 10 or 15% carbamide peroxide, respectively) exhibited similar but milder symptoms. The data indicate that ingestion of large doses of commercial preparations of tooth whiteners may be acutely toxic, sometimes fatal, to female laboratory rats. PMID:8360379

Cherry, D V; Bowers, D E; Thomas, L; Redmond, A F



Uterotrophic assay of percutaneous lavender oil in immature female rats.  


The estrogenic potential of lavender oil was evaluated in a percutaneous uterotrophic bioassay in immature female rats. Four groups of 10 immature female rats each were randomly selected on postpartum day (PPD) 16. During the 3-day treatment period (PPDs 19-21), the immature rats were separated from the dams, caged in groups of 5 in a litter box for 6 hours, and administered the vehicle control article (corn oil) or lavender oil at 20 or 100 mg/kg per day. All dosages were administered as a 5 mL/kg volume in a Hilltop Chamber (25 mm diameter; absorbent material removed) placed on the shaved back of each immature rat, and secured with micropore tape and Vetrap. A positive control group was gavaged twice daily with 2.5 ?g/kg per day of 17?-ethinyl estradiol. Daily observations included viability, clinical signs, body weights, and body weight gains. All rats were euthanized 24 hours after the third and final treatment, the uteri and ovaries were removed, and the paired ovaries and wet and blotted uterine weights were recorded. No unscheduled deaths occurred. No skin reactions were observed. Both dosages of lavender oil significantly reduced body weight gains after the third day of treatment, but terminal body weights and mean absolute and relative uterine weights did not differ significantly from vehicle control values. Positive controls showed significant increases in body weight and increased mean absolute and relative uterine weights as expected. Based on these data, lavender oil, at dosages of 20 or 100 mg/kg, was not active in the rat uterotrophic assay and gave no evidence of estrogenic activity. PMID:23358464

Politano, Valerie T; McGinty, Danielle; Lewis, Elise M; Hoberman, Alan M; Christian, Mildred S; Diener, Robert M; Api, Anne Marie



The role of the preputial glands in sexual attractivity of the female rat.  


This study shows that olfactory cues contribute to attractivity of the female rat but that the preputial glands are a minor source of such olfactory stimuli. In the experiments described, a residential plus-maze was used. The amount of time resident male rats spent in the vicinity of an estrous female rat was used as a measure of female attractivity. In the first experiment it was shown that male rats were attracted to anaesthetized estrous female rats but that these females were less attractive than unanaesthetized estrous females. In the second experiment it was shown that after removal of the preputial glands females were still attractive for male rats. The results of the third experiment demonstrated that estrous preputialectomized female rats remained attractive for male rats when they were anesthetized. When the resident male rats could make a choice between an estrous preputialectomized female and an estrous control female there was a tendency for the latter to be preferred. It can be concluded that olfactory cues enhance the attractivity of an estrous female rat, but that it is not the only sensory modality used by the female to attract a (distant) male. The preputial glands are of minor importance as a source of olfactory signals. PMID:3387478

Merkx, J; Slob, A K; van der Werff ten Bosch, J J



Quantitative alterations in the liver and adrenal gland in pregnant rats induced by Pyralene 3000  

SciTech Connect

Polychlorinated biphenyls (PCBs) are among the most widespread environmental pollutants known in the world. The half-life of PCBs is very long and, therefore, once released into the environment, they accumulate in food chains and tissues of various mammals, including man. Their presence can cause numerous toxic effects, e.g., hepatotoxicity, immunotoxicity, dermatotoxicity, neurotoxicity, and disorders of the reproductive system, among others. These effects depend on the distribution route in the organism, the rate of metabolism and excretion. Their characteristics are closely associated with the number and position of the chlorine atoms in the molecule. Previous studies of trichlorobiphenyl distributions in various tissues demonstrated that low chlorinated trichlorobiphenyls do no accumulate in endocrine organs, whereas higher chlorinated biphenyls, such as hexa- and octachlorobiphenyl, are deposited and retained in the adrenal gland. A selective distribution of radioabelled tetrachlorobiphenyl to the zona fasciculata, accompanied by morphometric evidence of the hypertrophy of the zona fasciculata, was also noted. The purpose of this study was to examine changes in the tissue structure of the pregnant rat liver and adrenal gland induced experimentally by Pyralene 3000 administration. We chose this commercial low chlorinated PCB because it was in use in Slovenia and, discharged from the electroindustrial plants, caused a serious incidence of environmental pollution in the region of Bela Krajina. Our further aim was to research the transplacental influences of Pyralene 3000 in rats. 17 refs., 1 fig., 3 tabs.

Vreci, M.; Sek, S.; Lorger, J.; Bavdek, S. [Univ. of Ljubljana, Gerbiceva (Slovenia); Pogacnik, A.



Pregnancy or stress decrease complexity of CA3 pyramidal neurons in the hippocampus of adult female rats.  


Pregnancy is a time of distinct neural, physiological and behavioral plasticity in the female. It is also a time when a growing number of women are vulnerable to stress and experience stress-related diseases, such as depression and anxiety. However, the impact of stress during gestation on the neurobiology of the mother has yet to be determined, particularly with regard to changes in the hippocampus; a brain area that plays an important role in stress-related diseases. Therefore, the aim of the present study was to understand how stress and reproductive state may alter dendritic morphology of CA1 and CA3 pyramidal neurons in the hippocampus. To do this, adult age-matched pregnant and virgin female Wistar rats were divided into two conditions: (1) control and (2) stress. Females in the stress condition were restrained for 1h/day for the last 2 weeks of gestation and at matched time-points in virgin females. Females were sacrificed the day after the last restraint session and brains were processed for Golgi impregnation. Dendritic length and number of branch points were quantified for apical and basal regions of CA1 and CA3 pyramidal neurons. Results show that regardless of reproductive state, stressed females had significantly shorter apical dendrites and fewer apical branch points in CA3 pyramidal cells. In addition, pregnant females, regardless of stress exposure, had less complex CA3 pyramidal neurons, as measured by Sholl analysis. No differences between conditions were seen in morphology of CA1 pyramidal neurons. This work shows that both repeated restraint stress and pregnancy affect dendritic morphology by decreasing complexity of CA3, but not CA1, neurons in the hippocampus. PMID:23036618

Pawluski, J L; Valença, A; Santos, A I M; Costa-Nunes, J P; Steinbusch, H W M; Strekalova, T



Effects of Perinatal Polychlorinated Biphenyls on Adult Female Rat Reproduction: Development, Reproductive Physiology, and Second Generational Effects  

PubMed Central

Perinatal exposures to endocrine-disrupting chemicals such as polychlorinated biphenyls (PCBs) can cause latent effects on reproductive function. Here, we tested whether PCBs administered during late pregnancy would compromise reproductive physiology in both the fetally-exposed female offspring (F1 generation), as well as in their female offspring (F2 generation). Pregnant Sprague-Dawley rats were treated with the PCB mixture Aroclor (A) 1221 (0, 0.1, 1 or 10 mg/kg) on embryonic days 16 and 18. Somatic and reproductive development of F1 and their F2 female offspring were monitored, including ages of eye opening, pubertal landmarks, and serum reproductive hormones. The results showed that low doses of A1221 given during this critical period of neuroendocrine development caused differential effects of A1221 on F1 and F2 female rats. In both generations, litter sex ratio was skewed towards females. In the F1 generation, additional effects were found including a significant alteration of serum luteinizing hormone (LH) in the 1 mg/kg A1221 group. The F2 generation showed more profound alterations, particularly with respect to fluctuations in hormones and reproductive tract tissues across the estrous cycle. On proestrus, the day of the preovulatory GnRH/gonadotropin surge, F2 females whose mothers had been perinatally exposed to A1221 exhibited substantially suppressed LH and progesterone concentrations, and correspondingly smaller uterine and ovarian weights on estrus, compared to F2 decendants of control rats. These latter changes suggest a dysregulation of reproductive physiology. Thus, low levels of exposure to PCBs during late fetal development cause significant consequences on the maturation and physiology of two generations of female offspring. These findings have implications for reproductive health and fertility of wildlife and humans.

Steinberg, Rebecca M.; Walker, Deena M.; Juenger, Thomas E.; Woller, Michael J.; Gore, Andrea C.



Runaway and Pregnant: Risk Factors Associated with Pregnancy in a National Sample of Runaway\\/Homeless Female Adolescents  

Microsoft Academic Search

Purpose: Homeless youth are at particularly high risk for teen pregnancy; research indicates as many as 20% of homeless young women become pregnant. These pregnant and homeless teens lack financial resources and adequate health care, resulting in increased risk for low- birth-weight babies and high infant mortality. This study investigated individual and family-level predictors of teen pregnancy among a national

Sanna J. Thompson; Kimberly A. Bender; Carol M. Lewis; Rita Watkins


Life history of female preferences for male faces: a comparison of pubescent girls, nonpregnant and pregnant young women, and middle-aged women.  


Although scientific interest in facial attractiveness has developed substantially in recent years, few studies have contributed to our understanding of the ontogeny of facial preferences. In this study, attractiveness of 30 male faces was evaluated by four female groups: girls at puberty, nonpregnant and pregnant young women, and middle-aged women. The main findings are as follows: (1) Preference for sexy-looking faces was strongest in young, nonpregnant women. (2) Biologically more mature girls displayed more adultlike preferences. (3) The intragroup consistency for postmenopausal women was relatively low. (4) In terms of the preference pattern, pregnant women were more similar to perimenopausal women than they were to their nonpregnant peers. (5) Preference for youthful appearance decreased with the age of the women. I argue that the life history of female preferences for male faces is, to a large extent, hormone-driven and underpinned by a set of evolutionary adaptations. PMID:22388946

Ko?ci?ski, Krzysztof



Vulnerability to (+)-Methamphetamine Effects and the Relationship to Drug Disposition in Pregnant Rats during Chronic Infusion  

PubMed Central

Chronic (+)-methamphetamine (METH) use during pregnancy increases the health risk for both mother and fetus. To provide insights into these risks, the relationship between changes in METH disposition and METH-induced pharmacological effects were studied in Sprague-Dawley rat dams and litters. Timed-pregnant rats (n = 5–6) were given saline or METH (5.6–17.8 mg/kg/day) by continuous sc infusion from gestational day (GD) 7 (before organogenesis) until GD21 (0–2 days before delivery). By GD11, all rats in the 17.8-mg/kg/day group died or were sacrificed for humane reasons. There were significant (p < 0.05) dose- and gestational time-dependent decreases in maternal body weight in the 10- to 13.2-mg/kg/day groups, which slowly recovered to near normal by GD21. Continued METH dosing in the surviving groups did not affect the mean pups/litter weight at the end of the experiment on GD21. While maternal and fetal METH and (+)-amphetamine serum concentrations were similar on GD21, brain concentrations were significantly greater in the dams (p < 0.05). Importantly, brain-to-serum ratios in the dams were 9:1 and 3:1 in the pups. METH systemic clearance (ClS) in dams significantly (p < 0.05) decreased from 52 ± 14 ml/min/kg on GD10 to 28 ± 6 ml/min/kg on GD21 in all dose groups, indicating late-gestational stage reductions in METH ClS. Overall, these findings suggest that there were two periods of increased susceptibility for dams and fetuses during chronic METH treatment. First was the period after the start of METH dosing in which neuroadaptation and tolerance to METH occurs in the adult. The second was at the end of pregnancy when METH clearance was significantly reduced.

White, Sarah J.; Laurenzana, Elizabeth M.; Gentry, William Brooks; Hendrickson, Howard P.; Williams, David Keith; Ward, Keith W.; Owens, Samuel Michael



Fetal translocation and metabolism of PAH obtained from coal fly ash given intratracheally to pregnant rats  

SciTech Connect

Polycyclic aromatic hydrocarbons (PAH) were extracted from coal fly ash collected from the electrostatic precipitator of a thermal power plant. The PAH extract was given intratracheally daily to pregnant rats (2 mg/100 g body weight) on d 18 and 19 of gestation. In addition of d 19 of gestation rats were also given (/sup 4/H)benzo(a)pyrene intratracheally. Rats were sacrificed on d 20 of gestation, and the distribution of (/sup 3/H)benzo(a)pyrene radioactivity and PAH of coal fly ash was studied in maternal lung, liver, and placenta, as well as in the liver and lung of the fetus. The radioactivity of intratracheally given benzo(a)pyrene was found in liver (68%), placenta (4%), fetal lung (1.9%), and fetal liver (1.4%) of maternal lung. Intratracheally administered PAH of coal fly ash were translocated to maternal liver and placenta, as well as to the liver and lung of the fetus. PAH of coal fly ash were also metabolized to several minor and major metabolites by maternal lung, liver, and placenta, as well as by the maternal fetal liver and lung. Some of the PAH metabolites in lung and liver were common; however, the major metabolite of liver, M-16, was different from the major metabolite M-16 of lung. The major PAH metabolite of placenta, M-15, and fetal liver, F-12, were common PAH metabolites. M-2 and M-6 of the placenta and F-5 and F-10 of the fetal lung were also common.

Srivastava, V.K.; Chauhan, S.S.; Srivastava, P.K.; Kumar, V.; Misra, U.K.



Effect of a leucine-supplemented diet on body composition changes in pregnant rats bearing Walker 256 tumor.  


Cancer patients present high mobilization of host protein, with a decrease in lean body mass and body fat depletion occurring in parallel to neoplastic growth. Since leucine is one of the principal amino acids used by skeletal muscle for energy, we investigated the changes in body composition of pregnant tumor-bearing rats after a leucine-supplemented diet. Sixty pregnant Wistar rats divided into six groups were fed a normal protein diet (18%, N) or a leucine-supplemented diet (3% L-leucine, L). The pregnant groups were: control (CN), Walker 256 carcinoma-bearing rats (WN), control rats pair-fed with tumor-bearing rats (pfN), leucine-supplemented (CL), leucine-supplemented tumor-bearing (WL), and leucine-supplemented rats pair-fed with tumor-bearing rats (pfL). At the end of pregnancy, all animals were sacrificed and body weight and tumor and fetal weight were determined. The carcasses were then analyzed for water, fat and total, collagen and non-collagen nitrogen content. Carcass weight was reduced in the WN, WL, pfN and pfL groups compared to control. The lean body mass and total carcass nitrogen were reduced in both tumor-bearing groups. Despite tumor growth and a decrease in fetal weight, there was a slight decrease in collagen (7%) and non-collagen nitrogen (8%) in the WL group compared with the WN group which showed a decrease of 8 and 12%, respectively. Although the WL group presented severe tumor growth effects, total carcass nitrogen and non-collagen nitrogen were particularly higher in this leucine-supplemented group compared to the WN group. These data suggest that the leucine-supplemented diet had a beneficial effect, probably attenuating body wasting. PMID:11262583

Ventrucci, G; Mello, M A; Gomes-Marcondes, M C



Stress in pregnancy: A new Wistar rat model for human preeclampsia  

Microsoft Academic Search

OBJECTIVE: Our study evaluated the effects of chronic and\\/or acute stress on pregnant and nonpregnant female rats. STUDY DESIGN: The rats were exposed to the sonic stimulus associated with overpopulation between days 7 and 14 of pregnancy. The rats were immobilized 2 days before the vascular reactivity experiments. RESULTS: In 14-day pregnant rats, chronic stress led to lower weight, increased

Nilton H. Takiuti; Soubhi Kahhale; Marcelo Zugaib



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.



Effects of oestradiol on brain lipid class and Fatty Acid composition: comparison between pregnant and ovariectomised oestradiol-treated rats.  


To determine the involvement of physiological doses of oestradiol on brain lipid composition, we have analysed the lipid class and fatty acid composition of phospholipids in the brain from pregnant and 17?-oestradiol-treated rats. Rats were randomly divided into three groups: ovariectomised control (OVX?+?VEH), ovariectomised oestradiol-treated (OVX?+?E(2) ) and pregnant (PREG) rats. Rats from the OVX?+?E(2) group were injected daily with different doses of 17?-oestradiol mimicking the plasma levels observed during pregnancy. Analyses of brain lipid class composition showed that physiological doses of oestradiol increased cholesterol levels of the OVX?+?E(2) group compared to the OVX?+?VEH group. It was also found that cholesterol levels in the PREG group were significantly lower than in the OVX?+?VEH and OVX?+?E(2) groups, indicating the involvement of gestational hormones other than oestradiol in the regulation of brain cholesterol during pregnancy. Brains from pregnant rats also exhibited reduced levels of plasmalogens and saturated fatty acids compared to the ovariectomised groups, especially in the second half of pregnancy. Interestingly, analyses of fatty acid composition of phospholipids revealed that physiological doses of oestradiol increased brain docosahexaenoic acid (DHA; 22:6 n-3) levels. Moreover, DHA levels in pregnant rats were similar to those observed in the OVX?+?E(2) group at all stages, suggesting that oestradiol is the main hormone in the regulation of brain DHA levels during pregnancy. Liver appears to be the major source for n-3 and n-6 long chain polyunsaturated fatty acids (LCPUFAs) DHA and arachidonic acid, which are released and transported to the maternal brain and the developing foetus under the influence of oestrogens. We also observed that the largest depots of n-3 and n-6 LCPUFA precursors (linolenic acid and linoleic acid, respectively) occur in adipose tissue triglycerides, which, in turn are significantly increased during pregnancy. Our observations are in accordance with an oestradiol-induced increased bioavailability of brain DHA in pregnant rats. We hypothesise that the reduction of maternal brain DHA observed at the end of pregnancy is a result of the very high demand DHA of foetal brain, which overcomes the maximal maternal (and likely foetal) capacity for de novo DHA synthesis in the liver and brain. PMID:22007691

Fabelo, N; Martin, V; González, C; Alonso, A; Diaz, M



Generalized lipidosis in newborn rats and guinea pigs induced during prenatal development by administration of amphiphilic drugs to pregnant animals  

Microsoft Academic Search

Summary  Pregnant rats and guinea pigs were treated throughout the second half of gestation with amphiphilic drugs (chlorphentermine,\\u000a chlorcyclizine, chloroquine) known to induce generalized lipidosis. The offspring were sacrificed immediately after birth,\\u000a and several tissues (lung, liver, kidney, spleen, pituitary gland, adrenal gland, spinal cord, hypothalamus) were examined\\u000a by electron microscopy. Generalized lipidosis was found in the offspring of both species,

Renate Lfillmann-Rauch; Brigitte Stoermer



Prior reproductive experience alters prolactin-induced macrophage responses in pregnant rats.  


Reproductive experience (i.e., pregnancy and lactation) induces physiological changes in mammals. A previous reproductive experience was recently shown to modulate the activity of dopaminergic hypothalamic systems while decreasing serum prolactin levels and oxidative burst activity in peritoneal macrophages. Dopamine receptor antagonists increase serum prolactin levels, and both prolactin and dopamine receptors may be involved in the modulation of macrophage activity, providing a means of communication between the nervous and immune systems. The present study evaluated the in vitro effects of prolactin and a dopamine D2 receptor antagonist on the peritoneal activity of macrophages from primigravid and multigravid female rats during the third trimester of pregnancy. Oxidative bursts and phagocytosis in peritoneal macrophages were evaluated by flow cytometry. Primigravid and multigravid Wistar rats, during the third trimester of pregnancy (i.e., days 17-21), were used. Peritoneal fluid samples from these rats were first incubated with prolactin (10 and 100nM) for different periods of time. The same procedure was repeated to evaluate the effects of domperidone (10 and 100nM) on macrophage activity. Our results showed that macrophages from multigravid rats responded more effectively to in vitro incubation with prolactin, especially with regard to the intensity and percentage of phagocytosis. Additionally, these effects were more pronounced after incubation periods of 30min or 4h. These data suggest that macrophages during a second pregnancy become more sensitive to the phagocytotic effects of prolactin. PMID:23714392

Carvalho-Freitas, Maria Isabel Roth; Anselmo-Franci, Janete A; Palermo-Neto, João; Felicio, Luciano F



Differential effects of chronic unpredictable stress on hippocampal CB1 receptors in male and female rats  

Microsoft Academic Search

Chronic unpredictable mild stress (CMS), an animal model of depression, downregulates hippocampal CB1 receptors in adult male rats. Given that endocannabinoids are implicated in modulating stress and anxiety and that women are vulnerable to stress-related disorders, we tested the effects of CMS on both female and male rats. Gonadectomized (gndx) and gonadally intact male and female rats were exposed to

Christian G. Reich; Michael E. Taylor; Margaret M. McCarthy



Runaway and Pregnant: Risk Factors Associated with Pregnancy in a National Sample of Runaway\\/Homeless Female Adolescents  

Microsoft Academic Search

PurposeHomeless youth are at particularly high risk for teen pregnancy; research indicates as many as 20% of homeless young women become pregnant. These pregnant and homeless teens lack financial resources and adequate health care, resulting in increased risk for low–birth-weight babies and high infant mortality. This study investigated individual and family-level predictors of teen pregnancy among a national sample of

Sanna J. Thompson; Kimberly A. Bender; Carol M. Lewis; Rita Watkins



The disposition of /sup 14/C-trimethyltin in the pregnant rat and fetus  

SciTech Connect

Trimethyltin (TMT) is a potent neurotoxicant. For unknown reasons, age at exposure to TMT may dramatically influence the severity of TMT-induced neuropathology. We have demonstrated previously that radiolabel derived from (/sup 14/C)-TMT given to pregnant dams on gestational day (GD) 17 is found in fetal brain and blood. The present study was designed to determine the distribution of radiolabel derived from (14C)-TMT to brain and other tissue in fetuses from dams dosed on either GD 12 or 17 with 7.0 mg/kg TMT chloride. Radioactivity in GD 12 and GD 17 maternal whole blood peaked 1 hour after IP treatment. Whole blood elimination half-lives were 12-15 days. Peak radiolabel concentrations in GD 12 maternal and fetal brain were only 11-30% of those from GD 17 animals, however, peak fetal brain concentrations of radiolabel were not different from their respective maternal brain concentrations. Radiolabel concentrations in liver, kidney, and adrenal of GD 17 dams were higher than those in corresponding GD 12 tissues. Combined urinary and fecal elimination of radiolabel for two weeks after dosing accounted for 31 and 22% of the GD 12 and 17 doses, respectively. It appears that gestational age influences the distribution and elimination of TMT in the rat.

Lipscomb, J.C.; Paule, M.G.; Slikker, W. Jr.



Prior access to a sweet is more protective against cocaine self-administration in female rats than in male rats.  


It is well established that female rats are more sensitive than male rats to the reinforcing effects of cocaine (Lynch, 2008 [42] for review). We hypothesized that greater preference for cocaine would support greater avoidance of a cocaine-paired taste cue in female vs. male rats. Moreover, at least in male rats, greater avoidance of the taste cue is associated with greater cocaine self-administration (Grigson and Twining, 2002 [3]). Thus, we anticipated that female rats would not only demonstrate greater avoidance of the drug-paired taste cue, but greater drug-taking as well. We tested these hypotheses by examining avoidance of a saccharin cue in male and female rats following several pairings with self-administered saline or cocaine (0.16, 0.33, or 0.66 mg/infusion). Contrary to expectations, the results showed that female rats exhibited less avoidance of the cocaine-associated saccharin cue than male rats and self-administered less, rather than more, cocaine, Thus, while female rats reportedly take more drug than male rats when the drug is presented in the absence of an alternative reward, they take less drug than male rats when the opportunity to self-administer cocaine is preceded by access to a palatable sweet. Females, then, may not simply be more sensitive to the rewarding properties of drug, but also to the reinforcing properties of natural rewards and this increase in sensitivity to sweets may serve to protect against drug-taking behavior. PMID:23474135

Cason, Angie M; Grigson, Patricia S



Isolated small uterine arteries from non-pregnant and term pregnant rats exhibit regulatory responses to elevations in extravascular pressure.  


An adequate blood supply is essential for the maintenance of uterine function and fetal health during parturition. However, labouring uterine contractions will impart compressive forces on small uterine arteries (SUA). We demonstrate that isolated, pressurised rat SUA arteries, pre-constricted with arginine vasopressin or high potassium solution, exhibit regulatory responses to elevations in extravascular pressure (EVP) which maintain internal diameter constant at EVPs of 0-40 mm Hg. This response is endothelium independent and is not modulated by pregnancy. No regulation was observed in calcium free solution. SUA myogenic responses to elevated EVP likely represents a mechanism for limiting reductions in uterine blood flow during uterine contraction. PMID:23195572

Withers, S; Taggart, M; Austin, C



Inhibitory effects of female sex hormones on urinary stone formation in rats  

Microsoft Academic Search

Inhibitory effects of female sex hormones on urinary stone formation in rats.BackgroundThe effects of female sex hormones on urinary stone formation are not known. This study was conducted to investigate the effects of these hormones on stone formation by using an ethylene glycol (EG) and vitamin D-induced rat urolithiasis model.MethodsAdult female Wistar rats were fed the same diet for four

Masanori Iguchi; Chisato Takamura; Tohru Umekawa; Takashi Kurita; Kenjiro Kohri



Prenatal testosterone induces sex-specific dysfunction in endothelium-dependent relaxation pathways in adult male and female rats.  


Prenatal testosterone (T) exposure impacts postnatal cardiovascular function, leading to increases in blood pressure with associated decreased endothelium-dependent vascular relaxation in adult females. Endothelial function in males is not known. Furthermore, which of the endothelial pathways contributes to endothelial dysfunction and if there exists sex differences are not known. The objective of this study was to characterize the relative contribution of nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF) to the impaired endothelium-dependent vasodilation in prenatal T-exposed adult males and females. Offspring of pregnant rats treated with T propionate or its vehicle were examined. Telemetric blood pressure levels and endothelium-dependent vascular reactivity were assessed with wire myography. Levels of nitric oxide synthase (NOS3) and Kcnn3 and Kcnn4 channel expression were examined in mesenteric arteries. Mean arterial pressure was significantly higher in T males and females than in controls. Endothelium-dependent acetylcholine relaxation was significantly lower in both T males and females. EDHF-mediated relaxation was specifically blunted in T males (Emax = 48.64% ± 3.73%) compared to that in control males (Emax = 81.71% ± 3.18%); however, NO-mediated relaxation was specifically impaired in T females (Emax = 36.01% ± 4.29%) compared with that in control females (Emax = 54.56% ± 6.37%). Relaxation to sodium nitroprusside and levcromakalim were unaffected with T-treatment. NOS3 protein was decreased in T females but not in T males. Kcnn3 expression was decreased in both T males and females compared to controls. These findings suggest that prenatal T leads to an increase in blood pressure in the adult offspring, associated with blunting of endothelial cell-associated relaxation and that the effects are sex-specific: EDHF-related in males and NO-related in females. PMID:23966325

Chinnathambi, Vijayakumar; Yallampalli, Chandrasekhar; Sathishkumar, Kunju



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.

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



The ontogeny of exploratory behavior in male and female adolescent rats ( Rattus norvegicus )  

Microsoft Academic Search

During adolescence, rats gain independence from their mothers and disperse from the natal burrow, with males typically dispersing further than females. We predicted that, if dispersal patterns are associated with responsiveness to novelty, exploratory behavior in novel environments would increase across adolescence, and males would explore more than females. Alternatively, females might explore more than males, if females are more

Debra A. Lynn; Gillian R. Brown



2-Hydroxyestradiol enhances binge onset in female rats and reduces prefrontal cortical dopamine in male rats.  


Women are more likely to suffer from a bingeing-related eating disorder, which is surprising, since estradiol reduces meal size and is associated with reduced binge frequency. This apparent contradiction may involve the estradiol metabolite, 2-hydroxyestradiol. We previously reported that female rats had faster escalations in shortening intake during the development of bingeing than did males, but acute administration of 2-hydroxyestradiol increased the intake of vegetable shortening to a greater extent in male rats once bingeing was established. Here, we report two separate studies that follow up these previous findings. In the first, we hypothesized that chronic exposure to 2-hydroxyestradiol would promote escalation of bingeing during binge development in ovariectomized female rats. In the second, we hypothesized that acute exposure to 2-hydroxyestradiol would enhance dopamine signaling in the prefrontal cortex after bingeing was established in male rats. In study 1, non-food-deprived female rats were separated into 3 groups: ovariectomized (OVX) with chronic 2-hydroxyestradiol supplementation (E), OVX with vehicle supplementation (O), and intact with vehicle (I). Each group was given access to an optional source of dietary fat (shortening) on Mon, Wed, and Fri for 4 weeks. 2-hydroxyestradiol supplementation prevented OVX-induced weight gain and enhanced escalation of shortening intake over the four-week period (ps<0.05). Additionally, in week 4, rats in the E group ate significantly more shortening than I controls, less chow than either the O or I group, and had a higher shortening to chow ratio than O or I (ps<0.05). Study 2 indicated that acute injection of 2-hydroxyestradiol abolished shortening-evoked dopamine efflux in the prefrontal cortex of bingeing male rats (p<0.05). Together, these studies indicate that 2-hydroxyestradiol can exacerbate bingeing as it develops and can suppress dopamine signaling in the prefrontal cortex once bingeing is established. PMID:23116652

Babbs, R K; Unger, E L; Corwin, R L W



Effects of pregnancy on glomerular dynamics: Micropuncture study in the rat  

Microsoft Academic Search

Effects of pregnancy on glomerular dynamics: Micropuncture study in the rat. Glomerular dynamics were investigated by micropuncture in 15-day pregnant Munich-Wistar rats. Female non-pregnant rats were used as control. In hydropenia, single nephron glomerular filtration rate (SNGFR) averaged 37.2 nl\\/min\\/g kidney weight in pregnant rats, and 26.2 nl\\/min\\/g kidney weight in controls (P < 0.0005). During pregnancy, mean glomerular plasma

Antonio Dal Canton; Giuseppe Conte; Ciro Esposito; Giorgio Fuiano; Raffaele Guasco; Domenico Russo; Massimo Sabbatini; Francesco Uccello; Vittorio E Andreucci



Effects of prenatal stress on the activity of the pituitary-ovarian system in female rats.  


The comparative analysis of hormonal status was performed in mature female rats with experimental deficiency of estrogens, which mothers were exposed to stress during pregnancy. High levels of follicle-stimulating hormone and luteinizing hormone, and significantly lower amount of estradiol were observed in intact prenatally stressed females in comparison with intact non-stressed female rats. The increase in the levels of follicle-stimulating hormone and luteinizing hormone, and the decrease in estradiol concentration were more pronounced in blood serum of prenatally stressed ovariectomized rats as distinct from intact non-stressed and prenatally stressed female rats, and non-stressed ovariectomized female rats. We can conclude that prenatally stressed ovariectomized rats were characterized by an increased sensitivity to exogenous hormonal interventions and high lability of functional state of the pituitary-ovarian system. PMID:24143356

Ordyan, N E; Fedotova, Yu O; Pivina, S G



Quantification of cysteine sulfinic acid decarboxylase in male and female rats: effect of adrenalectomy and methionine.  


Hepatic cysteine sulfinic acid decarboxylase (EC activity has been reported to decrease in response to both L-methionine (Met) feeding and adrenalectomy in rats. A series of experiments was conducted to (a) determine if CSAD depression was evident in female rats fed a methionine-supplemented diet; and (b) determine if adrenal hormones mediated the response of CSAD to dietary methionine. Cysteine sulfinic acid decarboxylase (CSAD) activity was measured in livers of male and female rats fed a methionine-supplemented diet. In female rat liver, CSAD activity was only 25% of the activity measured in livers of male rats. Hepatic enzyme activity in male rats fed a casein-based basal diet containing 0.6% L-methionine was 2.5-fold higher than activity in male rats fed a methionine-supplemented diet containing 1.35% L-methionine (+Met). Similarly, enzyme activity in livers of female rats fed the basal diet was 1.7-fold higher than in female rats fed a methionine-supplemented diet. CSAD activity in adrenalectomized (ADX) male rats fed the basal diet was depressed (990 +/- 120 nmol/min.g liver) compared to activity in intact controls (2347 +/- 89) and sham controls (2040 +/- 143) fed the basal diet. CSAD activity was further depressed in ADX, intact controls, and sham controls fed +Met. Immunochemical detection and quantification of CSAD protein in rat liver demonstrated that changes in CSAD protein were consistent with the observed decreased enzyme activity in female rats, ADX rats, and rats fed +Met. S-Adenosylmethionine and S-adenosylhomocysteine concentrations tended to increase in livers of rats fed +Met. ADX rats fed +Met had the greatest increase in S-adenosylmethionine and S-adenosylhomocysteine concentrations. The depression in hepatic CSAD observed after feeding +Met to rats does not appear to involve adrenal function. PMID:1567210

Jerkins, A A; Steele, R D



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

PubMed Central

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.

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



TCDD, dietary iron and hepatic iron distribution in female rats  

SciTech Connect

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a prototype for a large group of halogenated aromatic hydrocarbons, and is the most potent of these compounds. TCDD is an environmental pollutant with exceptional toxicity for certain mammalian and avian species. The liver is one of the principal target organs affected by TCDD in the rat and other laboratory species. TCDD induces many functional, biochemical and pathological changes, including altered lipid metabolism in the liver. Ferrous iron plays an important role in the initiation of lipid peroxidation. A proposed mechanism for the production of liver injury in chronic iron overload is that organelle damage leading to cell death occurs as a result of membrane lipid peroxidation initiated and promoted by intracellular iron. The presence of iron in subcellular fractions in vitro may catalyze lipid peroxidation and produce membrane damage. There is evidence for the occurrence of hepatic lipid peroxidation after TCDD administration. The purpose of this study was to determine if TCDD induced lipid peroxidation was associated with an increase in the iron content of liver and its subcellular fractions. The effect of TCDD administration on the iron content of whole homogenate, microsomes, mitochondria, and cytosol of livers of female rats fed defined diets containing deficient, normal and excessive levels of iron for 17, 24 and 31 days was investigated.

Al-Bayati, Z.A.F.; Stohs, S.J.; Al-Turk, W.A.



Juvenile male rats display lower cortical metabolic capacity than females  

PubMed Central

The juvenile brain undergoes marked maturational changes accompanied by major sex hormone changes. In particular, sex differences in neural substrates could underlie male-specific dysfunction in behavioral responses related to the prefrontal cortex. Sex differences in regional metabolic capacity of the cerebral cortex were investigated in juvenile Sprague-Dawley rats. At 6 weeks of age the brains were processed for quantitative histochemistry of cytochrome oxidase, a rate limiting enzyme in cellular respiration, which is an index of brain metabolic capacity. Quantitative image analysis revealed a main effect of sex with males displaying lower regional metabolic capacity than females in the dorsolateral and orbital prefrontal cortex and in the posterior parietal cortex. In addition, males separated for 6 hours/day from their mothers as pups showed greater ambulatory behavior in the novel open field and higher metabolism in the posterior parietal cortex relative to males separated for 15 min/day. This is the first study to show sex differences in brain metabolic capacity in regions such as the prefrontal cortex that may be hypometabolic in juvenile males relative to females.

Spivey, Jaclyn M.; Colorado, Rene A.; Conejo-Jimenez, Nelida; Gonzalez-Pardo, Hector; Gonzalez-Lima, F.



Antipsychotic polypharmacy increases metabolic dysregulation in female rats.  


Antipsychotic polypharmacy refers to the clinical practice of treating a patient with two or more antipsychotic drugs concurrently. There is abundant evidence in the clinical literature that treatment with antipsychotic polypharmacy is associated with an increased prevalence of drug side effects compared with monotherapy. This includes drug-induced metabolic side effects, such as glucose intolerance and insulin resistance. As these metabolic side effects have been accurately modeled in preclinical rodent paradigms using drug monotherapy, the goal of the present study was to determine the metabolic effects of antipsychotic polypharmacy using an established rodent model. In the first experiment, adult female rats were treated with clozapine (5 mg/kg), risperidone (1 mg/kg), vehicle, or clozapine + risperidone. In the second experiment, rats were treated with clozapine (5 mg/kg), haloperidol (0.1 mg/kg), vehicle, or clozapine + haloperidol. Animals were then subjected to a glucose tolerance test. Compared with vehicle-treated control animals, risperidone and haloperidol had no effect on any of the metabolic indices when administered on their own. Addition of risperidone to clozapine significantly increased fasting glucose, fasting insulin, and insulin resistance compared with the clozapine-only group. The addition of haloperidol to clozapine significantly increased fasting insulin levels, insulin resistance, and glucose intolerance compared with clozapine-only rats. These results are consistent with clinical studies and therefore indicate that animal models can successfully be used to study the metabolic side effects of antipsychotic drugs. Future studies related to understanding the physiological mechanisms involved remain a priority. PMID:23356730

Boyda, Heidi N; Procyshyn, Ric M; Tse, Lurdes; Xu, James; Jin, Chen Helen; Wong, Daniel; Pang, Catherine C Y; Honer, William G; Barr, Alasdair M




Technology Transfer Automated Retrieval System (TEKTRAN)

We have previously shown that pregnancy reduces the bone loss observed with alcohol consumption in female rats. We tested the idea that this protection might be due to increased circulating sex steroids. In the current study, 225 g female Sprague-Dawley rats (N = 6/group) were infused liquid diets...


CB 1 receptor mediation of cannabinoid behavioral effects in male and female rats  

Microsoft Academic Search

Rationale Cannabinoids have been shown to produce greater behavioral effects in female than male rats. Although central nervous system CB 1 receptors are known to mediate cannabinoid-induced behavioral effects in male rats, it is not known whether the same is true for females. Objective To determine if cannabinoid-induced antinociception and catalepsy are similarly mediated by central CB 1 receptors in

Alan H. Tseng; Rebecca M. Craft



Mating Stimulation Required for Mating-Induced Estrous Abbreviation in Female Rats: Effects of Repeated Testing  

Microsoft Academic Search

Mating stimulation, particularly vaginal–cervical stimulation, causes estrous abbreviation in female rats. In most previous studies, female rats were repeatedly tested for sexual behavior until estrous termination occurred. Thus, it was not clear whether sensory stimulation (e.g., flank stimulation, olfactory cues) received during the repeated testing procedure contributed to estrous abbreviation. In Experiment 1, we determined the effect of premating to

Amy L. Bennett; Meg E. Blasberg; Jeffrey D. Blaustein



Morphologic and histologic abnormalities in female and male rats treated with anabolic steroids  

Microsoft Academic Search

A two-part study was performed to determine the ef fects of high doses of anabolic steroids on weight, appetite, and organ histology. Initially, 30 white Wistar rats, 15 males and 15 females, were treated weekly with either 0.52 cc of physiologic saline or nandrolone decanoate. After 6 weeks, female treated and control rats had comparable weight gains, but male treated

Janet A. Yu-Yahiro; Roger H. Michael; David V. Nasrallah; Brian Schofield



Tobacco smoke-dependent changes in cytochrome P450 1A1, 1A2, and 2E1 protein expressions in fetuses, newborns, pregnant rats, and human placenta.  


Tobacco smoke (TS) was described as a mixture of numerous cytochrome P450 (P450) substrates, inducers, and inhibitors. These inducers and inhibitors may modify drug clearance and xenobiotic or endogenous metabolism affecting P450s expression. In the present study, the effect of gestation and TS on: (1) cytochrome P450 CYP1A1, CYP1A2, and CYP2E1 protein expressions, and (2) cytochrome P450-linked microsomal enzyme activities, were studied in fetal rat liver, rat, and human placenta and in newborn and adult rat hepatic and extrahepatic tissues. Non-pregnant and pregnant 4-month-old female Wistar rats were exposed to TS (500, 1,000, or 1,500 mg carbon monoxide per m(3) air) in a toxicological chamber for 3 weeks (6 h daily, 5 days weekly). Human placentas were sampled from non-smoking, passive smoking, or active smoking primiparas. The efficacy of exposure was assessed by measuring urine cotinine levels. The TS-dependent inductory effect on the expression of CYP1A1 and 1A2 and related monooxygenase activities, and the inhibitory/inductory effect on CYP2E1 expression in rat tissues were observed. Pregnancy was associated with decreased levels of constitutive CYP1A1 and 2E1 in hepatic and extrahepatic tissues, TS-inducible CYP1A2 expression in the liver, and CYP1A1 expression in lungs and heart, but had no inhibitory effect on TS-inducible CYP1A1 and 2E1 expression, EROD, and P450-cooperated enzyme activities in the liver, kidney, and, in the latter case, in the heart. The presence of TS-induced CYP1A1 protein was confirmed in rat and human placenta and showed in newborn liver and lungs. CYP1A2 and 2E1 proteins were detectable in fetal rat liver. It was concluded that the expression of CYP1A1, 1A2, and 2E1, which metabolize some drugs and activate carcinogens, is controlled by age-, pregnancy-, and tissue-specific regulatory mechanisms in rats. Gestational differences in the regulation of expression of CYP1A subfamily members are not excluded. CYP1A1 and 2E1, but not CYP1A2 inductory mechanisms seem to be functional in fetal liver at day 21 of pregnancy but they appeared to be uninducible under a TS exposure. In TS-exposed pregnant females and fetuses the effects of metabolic activation of CYP1A1 and 1A2 substrates might be reduced because of lower CYP expressions or poor induction, respectively. PMID:15448981

Czekaj, Piotr; Wiaderkiewicz, Anna; Florek, Ewa; Wiaderkiewicz, Ryszard



Social stress increases the acquisition of cocaine self-administration in male and female rats  

Microsoft Academic Search

The effect of social stress on the vulnerability to commence cocaine self-administration was examined in Sprague-Dawley rats repeatedly exposed to aggressive attack by a same-sex opponent. Both sexes were studied, since the factors influencing the acquisition of drug self-administration in females have not been defined. Male and female rats encountered an aggressive male or lactating female opponent on four separate

Margaret Haney; Stefania Maccari; Michel Le Moal; Hervé Simon; Pier Vincenzo Piazza



Behavioural actions of prolactin locally applied into the hippocampus of adult female rats  

Microsoft Academic Search

Summary The probable behavioural effects of rat prolactin (rPRL) locally applied into the ventral hippocampus (HPC) were studied in cycling female rats. Three experiments were performed examining the behavioural responses of rats subjected to three different situations: (i) Exploratory activity in an enriched holeboard (ii) exploratory activity under conflicting situation and (iii) escape behaviours in a forced swimming test. Behavioural

E. O. Alvarez; A. M. Banzan



The calcium channel current of pregnant rat single myometrial cells in short-term primary culture.  

PubMed Central

1. The passive and active electrical properties of pregnant rat single myometrial cells in short-term primary culture were analysed using a single-electrode voltage or current clamp. 2. Action potentials and membrane currents were recorded in the presence of tetraethylammonium chloride and 4-aminopyridine (10 mM each) and with Cs+ solution (4 M) in the microelectrode. 3. The voltage dependence, the action of Ca2+ antagonists and the effects of Sr2+ or Ba2+ substitution were studied. The peak Ca2+ current density was in the range 15-20 microA/cm2 in 10 mM-Ca2+ solution. 4. According to both measurement of the reversal potential of Ca2+ channel currents and comparison of the inward currents after correction for changing surface charge, the relative selectivity sequence of the Ca2+ channel for divalent cations was Ca2+ greater than Sr2+ = Ba2+. 5. The decay of Ca2+ channel current during a maintained depolarization was slowed when external Ca2+ was replaced by Sr2+ or Ba2+. The decay reflected an inactivation of Ca2+ channel conductance, as assessed by the decreased amplitude of inward tail currents following progressively longer depolarizations and the stable value of the reversal potential when Ca2+ channel current was increased during conditioning pulses. 6. Voltage-dependent inactivation was illustrated by inactivation of outward Ca2+ channel current due to K+ and/or Cs+ efflux with external Ba2+ or in the absence of any permeant divalent cation. 7. The relationship between inactivation and the intracellular Ca2+ concentration was assessed by a double-pulse method. Conditioning pulses that produced maximal Ca2+ current induced maximal inactivation; with stronger depolarizations, inactivation decreased but was not completely prevented at the expected Ca2+ reversal potential. Increasing the amount of Ca2+ entering the cell during the pre-pulse reduced both amplitude and kinetics of test Ca2+ currents. These results were not observed with Ba2+ as the charge carrier. 8. Ca2+ channel current inactivation was best fitted by a two-exponential function. The fast time constant of inactivation was larger in Ba2+ solution than in Ca2+ solution but both time constants showed little variation with membrane potential. The slow time constants of inactivation were steeply voltage dependent.(ABSTRACT TRUNCATED AT 400 WORDS)

Amedee, T; Mironneau, C; Mironneau, J



The in vivo distribution of an antidepressant drug (DMI) in male and female rats  

Microsoft Academic Search

The accumulation of IP injected 3H-desipramine (DMI) in the brain and in the liver has been studied in both male and female rats. The total amount of DMI in the brains of females is 2 to 4 times that found in the brains of males. In females the amount of DMI is highest on the day of estrus and lowest

Anat Biegon; David Samuel




EPA Science Inventory

Male and female Long-Evans rats were treated with epichlorohydrin (ECH) by oral gavage (males: 12.5, 25, and 50 mg/kg/day; females: 25, 50, and 100 mg/kg/day) for 21 and 14 days respectively, prior to mating trials with untreated animals. Treated females were further dosed until ...


Adrenocortical response to 17-Beta estradiol replacement in oophorectomized female sprague dawley rats.  


Objective: To determine the effect of estradiol treatment on serum corticosterone levels in Oophorectomized (OVX) female Sprague Dawley rats exposed to chronic restraint stress. Study Design: Experimental study. Place and Duration of Study: Department of Physiology, Army Medical College, Rawalpindi and National Institute of Health, Islamabad, from January to December 2008. Methodology: A total of 90 female Sprague Dawley rats (age: 90 ± 10 days), were divided into three groups, each having 30 rats. Group-I comprised of healthy control female rats whereas group-II and III were experimental female rats exposed to chronic restraint stress after bilateral Oophorectomy and called estradiol treated and vehicle treated groups. Estradiol treatment of Oophorectomized rats was done once daily for 2 weeks. At the end of experiment, the rats were sacrificed and intracardiac blood sampling was done to measure serum corticosterone levels by enzyme linked immunosorbent assay (ELISA) kit. Results: The restraint stress to estradiol treated rats for 2 weeks revealed that serum corticosterone levels were significantly increased (31.32 ± 5.46 ng/ml, p < 0.05) as compared to the healthy controls (17.48 ± 4.14 ng/ml). Conclusion: Chronic restraint stress results increases the serum corticosterone levels in Oophorectomized Sprague Dawley rats. Estradiol treatment increases the responsiveness of adrenal cortex of Oophorectomized female rats. PMID:24112252

Farid, Sadaf; Hussain, Muhammad Mazhar; Asad, Munazza



Studies on Apoptotic Changes in Combined Toxicity of Citrinin and Endosulfan in Pregnant Wistar Rats and Their Fetuses  

PubMed Central

Background: Citrinin (mycotoxin) and endosulfan (pesticide) both environmental contaminants easily enter the food chain and are caoomon causes of various toxicities. Materials and Methods: In the present investigation, citrinin (CIT) (10 mg/kg feed) and endosulfan (1 mg/kg body weight) were administered orally alone and in combination to pregnant Wistar rats from gestational day 6 to 20 to study their effect to cause apoptosis in the pregnant Wistar rats and their fetuses. Apoptosis was assessed in dams by agarose gel electrophoresis, flow cytometry and electron microscopy, while in the fetuses it was assessed by flow cytometry only. Result: Citrinin and endosulfan in the combination group caused apoptosis in an additive manner as there was increased number of apoptotic cells as compared to the individual toxin and control groups. The fetuses also showed increased number of apoptotic cells in the combination groups, which also indicated that both the toxins crossed the placental barrier. Conclusion: So it was concluded that apoptosis played a significant role in the pathogenesis of endosulfan and citrinin toxicity.

Singh, N. D.; Sharma, A. K.; Dwivedi, P.; Telang, A. G.; Kumar, M.; Patil, R. D.



Sensory mediation of female–male mounting in the rat: II. Role of tactile and conspecific cues  

Microsoft Academic Search

Although previous research has shown that olfactory cues mediate female–male mounting (FMM) in the rat, the role of other sensory modalities on FMM has not been investigated. The present study examined the display of female mounting of castrated male rats in bilevel chambers following different tactile or locomotor activity manipulations. Female rats (N=40) were ovariectomized (OVX), primed with estrogen (E)

Veronica M. Afonso; Vasiliki Bablekis; James G. Pfaus



Nature of changes in adrenocortical function in chronic hyperleptinemic female rats  

Microsoft Academic Search

Neonatal treatment of rats with monosodium l-glutamate, which destroys hypothalamic arcuate nucleus neuronal bodies, induces several metabolic abnormalities; as a result,\\u000a rats develop a phenotype of pseudoobesity. This study was designed to explore, in the monosodium l-glutamate-treated female rat, the influence of chronic hyperleptinemia on adrenal cortex functionality. For this purpose,\\u000a we evaluated in control and hypothalamic-damaged rats: (a) in

Mario Perelló; Griselda Moreno; Gisela Camihort; Georgina Luna; Gloria Cónsole; Rolf C. Gaillard; Eduardo Spinedi



Remodeling and angiotensin II responses of the uterine arcuate arteries of pregnant rats are altered by low- and high-sodium intake.  


Lowering and increasing sodium intake in pregnant rats evoke opposite changes in renin-angiotensin-aldosterone system (RAAS) activity and are associated with alterations of blood volume expansion. As augmented uterine blood flow during gestation is linked to increased circulatory volume, we wanted to determine if low- and high-sodium intakes affect the mechanical properties and angiotensin II (AngII) responses of the uterine vasculature. Non-pregnant and pregnant rats received a normal sodium (0.22% Na+) diet. On the 15th day of gestation some animals were moved to a low-sodium (0.03%) diet, whereas others were given NaCl supplementation as beverage (saline, 0.9% or 1.8%) for 7 days. All rats were killed after 7 days of treatment (eve of parturition). Uterine arcuate arteries (>100 microm) were set up in wire myographs under a tension equivalent to 50 mmHg transmural pressure. The pregnancy-associated increase in diameter of the uterine arteries was significantly attenuated on the low-sodium diet and 1.8% NaCl supplementation. The arcuate arteries of non-pregnant rats on the low-sodium diet showed markedly increased responses to AngII and phenylephrine (Phe). Pregnancy also resulted in heightened responses to AngII and Phe that were significantly reduced for the former agent in rats on the low-sodium diet. Sodium supplementation of non-pregnant rats did not affect the reactivity of the uterine arteries to AngII, but significantly reduced the effect of Phe (1 micromol/l). High salt also significantly diminished the elevated responses to AngII in the arteries of pregnant animals. It was observed that altered sodium intake affects the mechanical and reactive properties of the uterine arcuate arteries more importantly in pregnant than in non-pregnant rats. Low-salt intake similarly affected the reactivity of the uterine arcuate arteries to AngII and Phe, whereas high-salt intake more specifically affected AngII responses. These results showed that perturbations of sodium intake have major impacts on the structure and functions of the uterine arterial circulation, indicating RAAS involvement in uterine vascular remodeling and function during gestation. PMID:16452726

St-Louis, Jean; Sicotte, Benoît; Beauséjour, Annie; Brochu, Michèle



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



Characterization of the vasculature supplying the genital tissues in female rats  

PubMed Central

Introduction The internal pudendal arteries are the key resistance vessels controlling the peripheral circulatory component of sexual responses in both male and females. Previous studies in the male rat demonstrated that this vessel has markedly heightened susceptibility to vascular damage compared to other vessels in the body. Evidence suggests that the female may also be susceptible to vascular pathologies contributing to sexual dysfunction. Aim To characterize the anatomical, morphological and functional properties of the pudendal artery in female rats. Methods The pelvic arteries in young Sprague-Dawley female rats were dissected to generate a composite representation of the vascular gross anatomy. Morphometry was performed on perfusion-fixed pudendal arteries whereas others were mounted in a wire myograph to assess responses to vasoactive drugs. These measures were contrasted with a previous study examining male rats. Main Outcomes Measured Gross anatomy, lumen diameter, wall thickness, cross sectional area and contractile responses in the internal pudendal artery. Results The gross anatomy of the pudendal artery in female rats appears to parallel that found in male rats; acting as the primary feeder vessel of the clitoral, labial and vaginal tissue. Compared to the male rat, the female pudendal artery has a smaller lumen diameter (169±5.7 vs 303±13.8um), wall thickness (14±0.7 vs 47±2.2um) and cross-sectional area (8±0.4 vs 52±3.4×103 ?m2). These structural differences also translate into a decreased contractile capacity of the pudendal arteries from female rats vs. males (8.1±2.7 vs 20±1.4mN). Conclusions Although the gross anatomical features of the vasculature tree supplying the genital tissue in male and female rats appears to have similarities, the tissue specific properties of the vessel itself has a very different structure-function balance. We hypothesize this discordance likely reflects the very different sex-specific roles of this vessel in regulating blood flow during arousal.

Hannan, Johanna L.; Cheung, Geoffrey L.; Blaser, Mark C.; Pang, Judith J.; Pang, Stephen C.; Webb, R. Clinton; Adams, Michael A.



[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



Excess androgen during puberty disrupts circadian organization in female rats.  


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

Sellix, Michael T; Murphy, Zachary C; Menaker, Michael



Nicotine-Induced Antinociception in Male and Female Sprague-Dawley Rats.  

National Technical Information Service (NTIS)

Nicotine is a key pharmacologically-active ingredient in tobacco that has cognitive and behavioral effects, including antinociception. The present research examined effects of nicotine as an antinociceptive agent in male and female Sprague-Dawley rats. Ni...

N. Apatov



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...


Effects of Caffeine on Blood Flow in the Pregnant Rat and Associated Development of the Embryo/Fetus; Analytical Methods Development for Caffeine in Biological Media.  

National Technical Information Service (NTIS)

Using a radioactive microsphere technique, blood flow to several maternal organs, including ovary, uterus, decidua and chorioallantoic placenta (CAP), was measured following a single dose of 0, 120 or 160 mg/kg caffeine by gavage to pregnant CD rats on da...

C. A. Kimmel T. F. Grafton J. F. Young C. G. White G. L. Kimmel



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


Reproductive efficiency is of economic importance in commercial beef cattle production, since 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 inefficiencies associated with sub-fertile cows. To identify regions of the genome harboring variation affecting reproductive success, we applied a genome-wide association approach based on the >700,000 SNP marker assay. To include the largest number of individuals possible under the available budget, cows from several populations were assigned to extremes for reproductive efficiency, and DNA was pooled within population and phenotype before genotyping. Surprisingly, pools prepared from DNA of low reproductive cattle returned fluorescence intensity data intermediate between fertile females and males for SNP mapped to the Y chromosome (i.e., male sex chromosome). The presence of Y-associated material in low reproductive heifers or cows was confirmed by Y-directed PCR, which revealed that 21 to 29% of females in the low reproductive category were positive by a Y chromosome PCR test normally used to sex embryos. The presence of the Y chromosome anomaly was further confirmed with application of additional Y-specific PCR amplicons, indicating the likelihood of the presence of some portion of male sex chromosome in female cattle in various beef cattle herds across the U.S. Discovery of this Y anomaly in low reproductive females may make an important contribution to management of reproductive failures in beef cattle operations. PMID:22408089

McDaneld, T G; Kuehn, L A; Thomas, M G; Snelling, W M; Sonstegard, T S; Matukumalli, L K; Smith, T P L; Pollak, E J; Keele, J W



Sucrose ingestion decreases seizure onset time in female rats treated with lithium and pilocarpine.  


To extend previous work concerning diet and overt seizures in rats, we tested the hypothesis that ingestion of 10% sucrose-water could reduce seizure onset time (SOT) in rats given lithium and pilocarpine. We found that female but not male rats given free access to a 10% sucrose-water solution for 3 weeks exhibited shorter SOTs than age- and sex-matched control subjects. A separate experiment determined that SOT was significantly reduced whether female rats were provided 1, 2, 3, or 4 weeks of free access to sucrose. Moreover, the daily volume of sucrose ingested was significantly correlated (r=-0.42) with SOT regardless of the duration of sucrose treatment (in weeks). These findings suggest that a diet supplemented with sugar can facilitate the emergence of behavioral seizures in female rats given lithium and pilocarpine. We discuss the potential role of dopamine in mediating the sucrose-induced changes in SOT. PMID:15907749

Galic, M A; Persinger, M A



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



Dietary Genistein Affects Brain Protein Synthesis Rates in Ovariectomized Female Rats  

Microsoft Academic Search

The purpose of this study was to determine whether genistein affects the rate of brain protein synthesis in ovariectomized female rats. Experiments were con- ducted on three groups of 12-wk-old female rats: those in group 1 were ovariectomized to reduce the level of plasma sex hormone; those in group 2 were ovariectomized and fed diets containing 0.01% genistein; and those

Sunok Lyou; Emi Hirano; Kazuyo Tujioka; Yuka Mawatari; Kazutoshi Hayase; Satoshi Okuyama; Hidehiko Yokogoshi


Influence of Sex and Female Hormones on Nicotine-Induced Changes in Locomotor Activity in Rats  

Microsoft Academic Search

KANÝT, L., I. P. STOLERMAN, C. J. CHANDLER, T. SAIGUSA AND ?. PÖ?ÜN. Influence of sex and female hormones on nicotine-induced changes in locomotor activity in rats. PHARMACOL BIOCHEM BEHAV 62(1) 179–187 1999.—The acute and chronic effects of nicotine (0.4 mg\\/kg SC) on locomotor activity in photocell cages have been compared in male, female, and ovariectomized hooded rats. In Experiment

L. Kanýt; I. P. Stolerman; C. J. Chandler; T. Saigusa; ?. Pö?ün



Early postnatal diazepam exposure facilitates maternal behavior in virgin female rats  

Microsoft Academic Search

Virgin female rats do not display maternal behavior if they are not exposed to the pups during several days. This exposure is called induction. In this work we have studied the effects of early postnatal (PO-P16) diazepam (DZ) administration (1 and 2.5 mg\\/kg, SC) on the display of maternal behavior of virgin female rats when adults. Although we did not

M. C. R. Del Cerro; M. A. P. Izquierdo; C. Perez-Laso; M. Rodriguez-Zafra; A. Guillamon; S. Segovia



Impact of transient correction of increased adrenocortical activity in hypothalamo-damaged, hyperadipose female rats  

Microsoft Academic Search

Objective:To explore the effects of transient correction of enhanced corticoadrenal activity in monosodium L-glutamate (MSG)-damaged female rats on peripheral insulin sensitivity and in vitro retroperitoneal (RP) adipocyte function.Designs:A dose of 4 mg\\/g body weight (BW) of MSG or vehicle (CTR) was i.p. injected, once every 2 days, between days 2 and 10 of age, in female rats. Intact and 21

G Moreno; M Perello ´; G Camihort; G Luna; G Console; R C Gaillard; E Spinedi



Change of genes in calcium transport channels caused by hypoxic stress in the placenta, duodenum, and kidney of pregnant rats.  


Preeclampsia is a pregnancy-specific disease characterized by concurrent development of hypertension, proteinuria, and oxidative stress in the placenta. In this study, we induced hypoxic stress in rats during pregnancy to reproduce physiological conditions associated with preeclampsia. The maternal weight of hypoxic pregnant rats was lower than that of normoxic animals. The level of calcium ions were also increased in urine collected from the hypoxic animals. In contrast, urinary concentrations of sodium, chloride, and potassium ions declined in hypoxic rats, and developed to proteinuria. The expression of genes known as two biomarkers, sFLT1 (for preeclampsia) and HIF-1alpha (for hypoxia), were highly induced in the placenta, duodenum, and kidney by hypoxic stress. The overexpression of sFLT1 and HIF-1alpha demonstrated that our experimental conditions closely mimicked ones that are associated with preeclampsia. In the present study, we measured the expression of calcium transporters (TRPV5, TRPV6, PMCA1, NCKX3, NCX1, and CaBP-9k) in the placenta, duodenum, and kidney under hypoxic conditions on Gestational Day 19.5 in rats. Placental TRPV5, TRPV6, and PMCA1 expression was up-regulated in the hypoxic rats, whereas the levels of NCX1 and CaBP-9k were unchanged. In addition, NCKX3 expression was increased in the placenta of hypoxic rats. Duodenal expression of CaBP-9k, TRPV5, TRPV 6, and PMCA1 was decreased in the hypoxic rats, whereas levels of NCXs were not altered. Renal expression of NCKX3 and TRPV6 was increased, whereas NCX1 was decreased in the hypoxic rats compared to the normoxic controls. Taken together, these results indicate that physiological changes observed in the hypoxic rats were similar to ones associated with preeclampsia. Expression of calcium transport genes in the placenta, duodenum, and kidney perturbed by hypoxic stress during pregnancy may cause calcium loss in the urine, and thereby induce calcium-deficient characteristics of preeclampsia. PMID:23255337

Yang, Hyun; An, Beum-Soo; Choi, Kyung-Chul; Jeung, Eui-Bae



The expression of transforming growth factor   in pregnant rat myometrium is hormone and stretch dependent  

Microsoft Academic Search

From a quiescent state in early pregnancy to a highly contractile state in labor, the myometrium displays tremendous growth and remodeling. We hypothesize that the transforming growth factor b (TGFb )s ystem is involved in the differentiation of pregnant myometrium throughout gestation and labor. Furthermore, we propose that during pregnancy the mechanical and hormonal stimuli playaroleinregulatingmyometrialTGFbs.TheexpressionofTGFb1-3mRNAsandproteinswasexaminedbyreal-timePCR,Western immunoblot, and localized with

Oksana Shynlova; Prudence Tsui; Anna Dorogin; B Lowell Langille; Stephen J Lye



The disposition of ¹⁴C-trimethyltin in the pregnant rat and fetus  

Microsoft Academic Search

Trimethyltin (TMT) is a potent neurotoxicant. For unknown reasons, age at exposure to TMT may dramatically influence the severity of TMT-induced neuropathology. We have demonstrated previously that radiolabel derived from (¹⁴C)-TMT given to pregnant dams on gestational day (GD) 17 is found in fetal brain and blood. The present study was designed to determine the distribution of radiolabel derived from

J. C. Lipscomb; M. G. Paule; W. Jr. Slikker



Paradoxical air embolism through patent foramen ovale during consensual intercourse in a non-pregnant young female  

Microsoft Academic Search

Sudden vaginal bleeding and a cardiac arrest occurred in a 18-year-old female during consensual intercourse. Resuscitation procedures, applied at the arrival of a medical emergency team, restored the cardiac function allowing admission to hospital, where two vaginal mucosal lacerations were diagnosed and sutured. Cardiological investigations diagnosed a left ventricle myocardial infarction and a patent foramen ovale while a brain CT

Carlo Moreschi; Ugo Da Broi



Continuous place avoidance task reveals differences in spatial navigation in male and female rats  

Microsoft Academic Search

A new place navigation test was used to estimate the spatial orientation abilities of male and female rats. Animals had to avoid a room frame defined area on a rotating arena, entering of which was punished by mild footshock, i.e. rats had to avoid the same place in the room but different parts of the floor, which was rotated through

José M Cimadevilla; André A Fenton; Jan Bures



Central Prolactin Infusions Stimulate Maternal Behavior in Steroid-Treated, Nulliparous Female Rats  

Microsoft Academic Search

A series of experiments were conducted to determine whether and under what conditions central prolactin (PRL) administration would stimulate the onset of maternal behavior in female rats and to identify possible neural sites of PRL action. In each experiment ovariectomized, nulliparous rats whose endogenous PRL levels were suppressed with bromocriptine were tested for maternal behavior toward foster young. In experiments

Robert S. Bridges; Michael Numan; Paul M. Ronsheim; Phyllis E. Mann; Caroline E. Lupini



Increased severity of alcoholic liver injury in female verses male rats: A microarray analysis  

Microsoft Academic Search

Alcoholic liver disease (ALD) is an increasingly recognized condition that may progress to end-stage liver disease. In addition to alcohol consumption, genetic factors, dietary fatty acids, gender and viral infection potentiate the severity of alcoholic liver injury. In humans, significant gender differences in susceptibility to ALD are observed. In the intragastric infusion rat model of ALD, female rats developed more

Meena R. Sharma; Rathnagiri Polavarapu; Daniel Roseman; Viraj Patel; Eric Eaton; P. B. Kavi Kishor; Amin A. Nanji



The effect of genistein on some hormones and metabolic parameters in the immature, female rats  

Microsoft Academic Search

The influence of isoflavone - genistein on some hormones and metabolic parameters in sexually immature, female rats was studied. Rats (34 days old) were divided into three groups: control (receiving no genistein), receiving 1 or 5 mg of genistein\\/kg body weight (BW). The tested compound was administered intragastrically, i.e. by using a cannula inserted via oesophagus into the stomach once

L. Nogowski; E. Nowicka; T. Szkudelski; K. Szkudelska



Technology Transfer Automated Retrieval System (TEKTRAN)

Dietary copper (Cu) deficiency reduces iron (Fe) in male rats, but whether this occurs in female rats has been questioned. The mechanism for reduced Fe absorption in Cu deficiency is unknown, but may involve the intestinal Cu-dependent ferroxidase Dephaestin (Hp). A 2 x 2 factorial experiment was de...


Chronic anti-phencyclidine monoclonal antibody therapy decreases phencyclidine-induced in utero fetal mortality in pregnant rats  

PubMed Central

Illicit drug use during pregnancy is a serious social and public health problem inflicting an array of deleterious effects on both mother and offspring. We investigated the hypothesis that a murine anti-phencyclidine (PCP) monoclonal antibody (mAb6B5; KD=1.3 nM) can safely protect mother and fetus from PCP-induced adverse health effects in pregnant rats. Pregnant Sprague-Dawley rats (n=4–5) were intravenously administered bolus injections of PCP (1 mg/kg) on multiple days during pregnancy. They were also chronically treated with anti-PCP mAb6B5 at 45 mg/kg as a PCP antagonist. This dose provided one mAb-PCP binding site for every four PCP molecules. Therapeutic and safety study endpoints included pregnancy outcome (litter size, number of live vs. dead pups), maternal hemodynamic status and locomotor activity. Maternal hemodynamic changes (i.e., blood pressure and heart rate) and locomotor activity were measured in dams from gestation days 6–21 (one day antepartum) using a radiotelemetry-tracking device with a femoral arterial pressure catheter. This mAb6B5 treatment regimen significantly (p=0.008) reduced the number of PCP-induced in utero fetal deaths (odds ratio=3.2; 95%CI 1.3 to 7.9) and significantly (p<0.05) reduced acute PCP-induced maternal locomotor effects in the second trimester. Maternal hemodynamic responses to PCP were not significantly affected by mAb6B5 treatment. In conclusion, these data suggest that anti-PCP mAb treatments administered during pregnancy can safely protect a mother and her fetus(es) from PCP-related morbidity and mortality even when the mAb dose is too low to significantly prevent other PCP-induced maternal pharmacological effects.

Hubbard, JJ; Laurenzana, EM; Williams, DK; Gentry, WB; Owens, SM



Timing and route of exposure affects crystal formation in melamine and cyanuric exposed male and female rats: gavage vs. feeding.  


Effects of the dosing matrix and timing on the onset of renal crystal formation were evaluated in male and non-pregnant female rats (Fisher 344) exposed to both melamine (MEL) and cyanuric acid (CYA) for 28 days. Rats were fed ground feed containing 60 ppm MEL and 60 ppm CYA, (5 mg/kg bw/day equivalent), or exposed via oral gavage to carboxymethylcellulose containing 5 mg/kg bw MEL followed by 5 mg/kg bw CYA either consecutively (<1 min apart) or delayed 45 min after MEL. Staggered gavage exposure to MEL/CYA caused extensive renal crystal formation as compared to when the two compounds were administered consecutively or in feed. Treatment related effects included reduced weight gain, feed consumption, and testicular weight and increased kidney weight, water consumption and urine output. Animals from the staggered MEL/CYA gavage exposure group became ill and were removed after 9 days of exposure. Approximately 1 week after the initiation of exposure microscopic urinalysis revealed MEL/CYA crystals in both groups of gavaged animals but not in the MEL/CYA feed treatment groups. Urinary crystals were smaller (10 ?m) in animals consecutively gavaged. In contrast the urinary crystals were larger (20-40 ?m) and frequently clumped in the animals in the staggered gavage group. PMID:22963836

Sprando, Robert L; Reimschuessel, Renate; Stine, Cynthia B; Black, Thomas; Olejnik, Nicholas; Scott, Michael; Keltner, Zachary; Bandele, Omari; Ferguson, Martine; Nemser, Sarah M; Tkachenko, Andriy; Evans, Eric; Crosby, Tina; Woodling, Kellie; Loukotková, Lucie; da Costa, Gonçalo Gamboa



A calcium-deficient diet in pregnant, nursing rats induces hypomethylation of specific cytosines in the 11?-hydroxysteroid dehydrogenase-1 promoter in pup liver.  


Prenatal undernutrition affects offspring phenotype via changes in the epigenetic regulation of specific genes. We hypothesized that pregnant females that were fed a calcium (Ca)-deficient diet would have offspring with altered hepatic glucocorticoid-related gene expression and altered epigenetic gene regulation. Female Wistar rats ate either a Ca-deficient or control diet from 3 weeks before conception to 21 days after parturition. Pups were allowed to nurse from their original mothers and then euthanized on day 21. Methylation of individual cytosine-guanine dinucleotides in the phosphoenolpyruvate carboxykinase (Pck1), peroxisome proliferator-activated receptor ? (Ppara), glucocorticoid receptor (Nr3c1), 11?-hydroxysteroid dehydrogenase-1 (Hsd11b1), and 11?-hydroxysteroid dehydrogenase-2 (Hsd11b2) promoters was measured in liver tissue using pyrosequencing. For each gene, quantitative real-time polymerase chain reaction was used to assess mRNA levels in liver tissue. Overall Hsd11b1 methylation was lower in the Ca-deficient group than in the control group; however, overall methylation of each other gene did not differ between groups. Serum corticosterone levels in male pups from Ca-deficient dams were higher than those in control pups. Expression of Pck1 and Nr3c1 was lower in the Ca-deficient group than in the control group. A Ca-deficient diet for a dam during gestation and early nursing may alter glucocorticoid metabolism and lead to higher intracellular glucocorticoid concentrations in the hepatic cells of her offspring; moreover, this abnormal glucocorticoid metabolism may induce the metabolic complications that are associated with Ca deficiency. These findings indicated that prenatal nutrition affected glucocorticoid metabolism in offspring in part by affecting the epigenome of offspring. PMID:24176236

Takaya, Junji; Iharada, Anna; Okihana, Hiroyuki; Kaneko, Kazunari



Alcohol-induced suppression of gluconeogenesis is greater in ethanol fed female rat hepatocytes than males  

Microsoft Academic Search

The impact of alcohol-induced suppression on hepatic gluconeogenesis (HGN) after chronic ethanol consumption between males and females is unknown. To determine the effects of chronic alcohol consumption (8 weeks) on HGN, the isolated hepatocyte technique was used on 24h fasted male and female Wistar rats. Livers were initially perfused with collagenase and the hepatocytes were isolated. Aliquots of the cell

Ken D. Sumida; Alma A. Cogger; Aleksey V. Matveyenko



Behavioral Effects Of 8-OH-DPAT in Chronically Stressed Male and Female Rats  

Microsoft Academic Search

The present study tested the hypothesis that chronic stress desensitizes serotonergic 5-HT1A receptors and alters behavioral changes following 5-HT1A agonist administration. Eating, acoustic startle response (ASR), and locomotor activity were measured in stressed and nonstressed male and female rats after 8-OH-DPAT administration. Stressed rats were paired and stressed by around-the-clock intermittent foot shock. Controllable stress (CS) rats could avoid\\/terminate shock

Maurice L Sipos; Richard A Bauman; John J Widholm; G. Jean Kant



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.

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



Maternal care associates with play dominance rank among adult female rats.  


Variations in maternal care influence important life history traits that determine reproductive fitness. The adult female offspring of mothers that show reduced levels of pup licking/grooming (LG; i.e., low-LG mothers) show increased defensive responses to stress, accelerated pubertal development, and greater sexual receptivity than the female offspring of high-LG mothers. Amongst several species an accelerated pattern of reproductive development is associated with increased dominance-related behaviors and higher social rank. We hypothesize that rats from low-LG dams may thus also secure higher social rank as a means to compete for limited resources with conspecifics. In this study, social interactions were observed in triads of adult female rats aged p90 that received low, mid, and high levels of pup LG over the first week of life. Low- and mid-LG females had the highest pinning scores and high-LG rats the lowest, showing that low- and mid-LG adult females engage in greater play dominance-related behavior. Likewise, low- and mid-LG rats spent significantly more time drinking following 24?hr of water deprivation in a water competition test thus allowing them to secure a limited resource more easily than high-LG rats. Interestingly, pinning by play dominant females was increased when subordinates were sexually receptive (proestrus/estrus), suggestive of a process of reproductive suppression. Some evidence suggests that low-LG and mid-LG rats also show greater fecundity than high-LG rats. Variations in maternal care may thus have a long-term influence on the development of play dominance and possibly social rank in the female rat, which might contribute to reproductive success within a competitive environment. © 2012 Wiley Periodicals, Inc. Dev Psychobiol 55: 745-756, 2013. PMID:22786820

Parent, Carine I; Del Corpo, Adina; Cameron, Nicole M; Meaney, Michael J



In Utero and Lactational Exposure to TCDD; Steroidogenic Outcomes Differ in Male and Female Rat Pups  

Microsoft Academic Search

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) has a potency to induce decreased fertility and structural reproductive anomalies in male and female mammals. While the activity profile of sex steroid hormone production distinctly differs in developing males and females, we wanted to analyze sex-specific effects of TCDD introduced in utero and via lactation on gonadal steroidogenesis and gonadotropin levels in male and female rat infant

S. A. Myllymaki; T. E. Haavisto; L. J. S. Brokken; M. Viluksela; J. Toppari; J. Paranko



Neonatal isolation enhances acquisition of cocaine self-administration and food responding in female rats.  


We showed previously that neonatal isolation (ISO) enhances acquisition of cocaine self-administration in adult male rats without altering acquisition of food responding. Female rats show poorer performance in learning tasks and are differentially affected by stress compared to male rats. Thus, we investigated whether ISO alters acquisition of operant responding for cocaine and food in female rats with comparison to male rats. Litters were subjected to ISO or were non-handled (NH). Activity levels were assessed in adult rats. Then, rats were implanted with jugular catheters and allowed to self-administer cocaine under a fixed-ratio 1 (FR1) schedule of reinforcement using an escalating dose presentation procedure. Cocaine intake, discrimination of active versus inactive levers, and ineffective active lever responses were tabulated. Effects of non-contingent cocaine infusions (primes) and increasing FR on responding were then assessed. Other rats were allowed to lever press for food under an FR1 schedule (10 s time-out). ISO enhanced acquisition of operant responding for food and cocaine in female rats. The latter was demonstrated by better lever discrimination, emission of fewer ineffective responses, and superior performance in response to primes. Yet, NH females ingested more cocaine than ISO females during the initial acquisition phase. In male rats, ISO enhanced acquisition of cocaine self-administration but not food responding. Activity levels were unaffected by ISO or gender. These data confirm and extend our previous findings demonstrating the enduring effects of ISO on adult self-administration behavior and emphasize the importance of measuring behavioral patterns versus intake in acquisition studies. PMID:15084429

Kosten, Therese A; Sanchez, Hayde; Zhang, Xiang Yang; Kehoe, Priscilla



Immunomodulatory Effects of Estradiol and Cadmium in Adult Female Rats  

Microsoft Academic Search

A wide range of toxic effects has been associated with cadmium (Cd) exposure in mammals. However, the physiological factors that modulate these effects have received limited attention. We have previously demonstrated that neonatal exposure of rats to Cd during lactation results in sex-specific immunotoxic effects in both juvenile and adult rats. The objectives of this study were to determine the

Stephane Pillet; Michele D'Elia; Jacques Bernier; Jean-Marie Bouquegneau; Michel Fournier; Daniel G. Cyr



Oral Metformin Treatment Prevents Enhanced Insulin Demand and Placental Dysfunction in the Pregnant Rat Fed a Fructose-Rich Diet  

PubMed Central

The intake of a fructose-rich diet (FRD) in the normal female rat induces features similar to those observed in the human metabolic syndrome phenotype. We studied the impact of FRD administration to mothers on pregnancy outcome. On gestational day (Gd) zero rats were assigned to either group: ad libitum drinking tap water alone (normal diet, ND) or containing fructose (10% w/vol; FRD) through pregnancy; all rats were fed a Purina chow diet ad libitum ND and FRD rats were daily cotreated or not with metformin (60?mg/Kg/day oral; ND + MF and FRD + MF) and submitted to a high glucose load test on Gd 14. Additionally, placentas from different groups were studied on Gd 20. Data indicated that: (1) although FRD rats well tolerated glucose overload, their circulating levels of insulin were significantly higher than in ND rats; (2) the mesometrial triangle blood vessel area was significantly lower in placentas from FRD than ND dams; (3) the detrimental effects of FRD administration to mothers were ameliorated by metformin cotreatment. Our study suggests that excessive intake of fructose during pregnancy enhanced the risk for developing gestational diabetes and subsequent preeclampsia, and that metformin prevented the poor pregnancy outcome induced by FRD.

Alzamendi, Ana; Del Zotto, Hector; Castrogiovanni, Daniel; Romero, Jose; Giovambattista, Andres; Spinedi, Eduardo



Pineal melatonin synthesis and release are not altered throughout the estrous cycle in female rats.  


Melatonin times reproduction with seasons in many photoperiodic mammalian species. Whether sexual hormones reflect on melatonin synthesis is still debated. The aim of this work was to study, using a large panel of technical approaches, whether the daily profile of pineal melatonin synthesis and release varies with the estrous cycle in the female rat. The mRNA levels and enzyme activities of the melatonin synthesizing enzymes, arylalkylamine N-acetyltransferase and hydroxyindole-O-methyltransferase were similar at the four stages of the rat estrous cycle. The endogenous release of melatonin, followed by transpineal microdialysis during six consecutive days in cycling female rats, displayed no significant variation during this interval. Taken together, the present results demonstrate that there is no regular fluctuation in the pineal metabolism leading to melatonin synthesis and release throughout the estrous cycle in female rats. PMID:12485372

Skorupa, Ana-Lucia; Garidou, Marie-Laure; Bothorel, Béatrice; Saboureau, Michel; Pévet, Paul; Neto, José Cipolla; Simonneaux, Valérie



Sex differences in (+)amphetamine and (+)-methamphetamine-induced behavioral response in male and female Sprague–Dawley rats  

Microsoft Academic Search

(+)-Methamphetamine (METH) and (+)-amphetamine (AMP) are structurally similar drugs that are reported to induce similar pharmacological effects in rats of the same sex. Because pharmacokinetic data suggest female rats should be more affected than males, the current studies sought to test the hypothesis that the behavioral and temporal actions of METH and AMP should be greater in female Sprague–Dawley rats

Alessandra Milesi-Hallé; Donald E. McMillan; Elizabeth M. Laurenzana; Kelly A. Byrnes-Blake; S. Michael Owens



Effects of perinatal, combined exposure to 1,4-dichlorobenzene and 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene on rat female reproductive system.  


Prenatal or early postnatal exposure to some synthetic chemicals may affect the later reproductive system of the offspring. 1,4-Dichlorobenzene (DCB) is used as an air freshener and a moth repellent and 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (p,p'-DDE) is a persistent metabolite of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane that was used as a pesticide before. DCB concentrations of residential air and oral p,p'-DDE intake through marine products are demonstrated to be rather high in Japan. Such situations lead to high body burden of these pollutants in pregnant women. Consequently, foetuses and neonates will be exposed much more to DCB and p,p'-DDE via the mother. Therefore, the effects of the perinatal, combined exposure to DCB and p,p'-DDE on the female reproductive system have been investigated in mature rat female offspring of dams ingesting 25 p.p.m. DCB (approximately 2 mg/kg) and 125 p.p.m. p,p'-DDE (approximately 10 mg/kg) during the gestational and lactational period. Sexual maturation was fully developed in the rat female offspring perinatally exposed to DCB and/or p,p'-DDE through maternal exposure. The combined effect of DCB and p,p'-DDE was observed, and the ovarian weight was seen to decrease to approximately 80% of the control rat in matured female offspring following perinatal exposure to DCB and p,p'-DDE. This alteration might lead to reproductive dysfunction in matured female offspring. However, biological relevance of the alteration in the ovary remained uncertain in the present study. Further investigations concerning the reproductive function and mechanistic implication are required for elucidating the combined effects of perinatal exposure to DCB and p,p'-DDE on the later female reproductive system entirely. PMID:18341512

Makita, Yuji



Aldosterone metabolism in the isolated perfused liver of female and male rats  

SciTech Connect

A sex-dependent metabolism of aldosterone has been reported in intact rats. To further characterize the hepatic elimination of aldosterone and its sex dependence, the metabolism of d-(4-14C)aldosterone was studied in isolated perfused liver from male and female Wistar rats, from male rats castrated 3 weeks before experiments, and from younger male rats (same body weight as the female rats). The livers were perfused at a constant flow rate in a recirculating mode with a hemoglobin-free medium containing aldosterone at initially 1 nM. Perfusate aldosterone was measured by a specific RIA. Total 4-14C radio-activity in perfusate and bile was determined. The perfusate (4-14C)aldosterone radiometabolite concentration was calculated. The radiometabolite pattern in additional experiments was studied by HPLC. The male rats exhibited 10% higher systolic blood pressure (P less than 0.05) and 51% higher fasting values of plasma aldosterone (P less than 0.05) compared to those in the female rats. In female rats the hepatic clearance rate of aldosterone per 100 g BW was 72% higher than that in male rats (11.2 +/- 2.7 to 6.5 +/- 1.8 ml/min: P less than 0.01), and that expressed per g liver wet wt was 75% higher (3.5 +/- 1.0 to 2.0 +/- 0.7 ml/min; P less than 0.01). When female rats were compared to younger male rats with the same body weight, 33% higher hepatic aldosterone clearance rates were still found in female rats (21.0 +/- 5.4 to 15.8 +/- 3.2 ml/min; P less than 0.05), and 51% higher values when expressed per g liver wet wt (3.5 +/- 1.0 to 2.3 +/- 0.5 ml/min; P less than 0.01). No difference in the aldosterone clearance rate was observed in castrated male rats compared to that in noncastrated male rats. 4-14C-Labeled radiometabolite levels accumulated similarly in the perfusate of livers of both sexes.

Egfjord, M.; Olgaard, K. (Rigshospitalet, Copenhagen (Denmark))



[Chronic administration of estradiol to ovariectomized female Wistar rats causes development of hypoxic pulmonary hypertension].  


We have studied the role of female sex hormone estradiol in the development of hypoxic pulmonary arterial hypertension. Previously, it was shown that the development of pulmonary hypertension in Wistar female rats is accompanied by a twofold increase in the estradiol level. Ovariectomy reduces the degree of pulmonary hypertension in these animals. In this work, the effect of various chronic doses of exogenous estradiol (5 and 15 microg/kg per day) on the development of hypoxic pulmonary hypertension in Wistar female rats has been studied. Pulmonary hypertension was induced by exposure to hypobaric hypoxia (10 h a day for 2 weeks) at simulated altitude of 5000 m (O2 concentration reduced to 10%). The administration of estradiol in different doses (5 and 15 microg/kg per day) for 21 day initiated the development of pulmonary hypertension in ovariectomized Wistar female rats. PMID:23901461

Kovaleva, Iu O; Artem'eva, M M; Medvedev, O S; Medvedeva, N A



Serotonergic projections from the caudal raphe nuclei to the hypoglossal nucleus in male and female rats  

PubMed Central

The respiratory control system is sexually dimorphic. In many brain regions, including respiratory motor nuclei, serotonin (5HT) levels are higher in females than in males. We hypothesized that there could be sex differences in 5HT input to the hypoglossal nucleus, a region of the brainstem involved in upper airway control. Adult Fischer 344 rats were anesthetized and a retrograde transsynaptic neuroanatomical tracer, Bartha pseudorabies virus (PRV), was injected into the tongue. Sections through the medulla were reacted immunocytochemically for the presence of (i) PRV, (ii) tryptophan hydroxylase (TPH; marker of 5HT neurons), (iii) PRV combined with TPH, and (iv) 5HT. Sex hormone levels were measured in female rats and correlated with TPH immunoreactivity, as hypoglossal 5HT levels vary with the estrous cycle. The number of PRV neurons was comparable in male and female rats. The number and distribution of TPH immunoreactive neurons in the caudal raphe nuclei were similar in male and female rats. The subset of 5HT neurons that innervate hypoglossal motoneurons was also similar in male and female rats. With the exception of the ventrolateral region of the hypoglossal nucleus, 5HT immunoreactivity was similar in male and female rats. These data suggest that sex differences in 5HT modulation of hypoglossal motoneurons in male and female rats are not the result of sex differences in TPH or 5HT, but may result from differences in neurotransmitter release and reuptake, location of 5HT synaptic terminals on hypoglossal motoneurons, pre- and postsynaptic 5HT receptor expression, or the distribution of sex hormone receptors on hypoglossal or caudal raphe neurons.

Barker, Jessica R.; Thomas, Cathy F.; Behan, Mary



Characterization of biliary conjugates of 4,4'-methylenedianiline in male versus female rats  

SciTech Connect

4,4'-Methylenedianiline (4,4'-diaminodiphenylmethane; DAPM) is an aromatic diamine used in the production of numerous polyurethane foams and epoxy resins. Previous studies in rats revealed that DAPM initially injures biliary epithelial cells of the liver, that the toxicity is greater in female than in male rats, and that the toxic metabolites of DAPM are excreted into bile. Since male and female rats exhibit differences in the expression of both phase I and phase II enzymes, our hypothesis was that female rats either metabolize DAPM to more toxic metabolites or have a decreased capacity to conjugate metabolites to less toxic intermediates. Our objective was thus to isolate, characterize, and quantify DAPM metabolites excreted into bile in both male and female bile duct-cannulated Sprague Dawley rats. The rats were gavaged with [{sup 14}C]-DAPM, and the collected bile was subjected to reversed-phase HPLC with radioisotope detection. Peaks eluting from HPLC were collected and analyzed using electrospray MS and NMR spectroscopy. HPLC analysis indicated numerous metabolites in both sexes, but male rats excreted greater amounts of glutathione and glucuronide conjugates than females. Electrospray MS and NMR spectra of HPLC fractions revealed that the most prominent metabolite found in bile of both sexes was a glutathione conjugate of an imine metabolite of a 4'-nitroso-DAPM. Seven other metabolites were identified, including acetylated, cysteinyl-glycine, glutamyl-cysteine, glycine, and glucuronide conjugates. While our prior studies demonstrated increased covalent binding of DAPM in the liver and bile of female compared to male rats, in these studies, SDS-PAGE with autoradiography revealed 4-5 radiolabeled protein bands in the bile of rats treated with [{sup 14}C]-DAPM. In addition, these bands were much more prominent in female than in male rats. These studies thus suggest that a plausible mechanism for the increased sensitivity of female rats to DAPM toxicity may be decreased conjugation of reactive DAPM metabolites, leading to greater levels of protein adduct formation.

Chen, Kan; Cole, Richard B. [Department of Chemistry, University of New Orleans, New Orleans, LA (United States); Santa Cruz, Vicente [Department of Pathology, University of Texas Medical Branch, Galveston, TX (United States); Blakeney, Ernest W. [Department of Chemistry, Centenary College, Shreveport, LA (United States); Kanz, Mary F. [Department of Pathology, University of Texas Medical Branch, Galveston, TX (United States); Dugas, Tammy R. [Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center-Shreveport, 1501 Kings Highway, Shreveport, LA 71130 (United States)], E-mail:



Physiologically based pharmacokinetic modeling of the pregnant rat: A multiroute exposure model for trichloroethylene and its metabolite, trichloroacetic acid. (Reannouncement with new availability information). Interim report, April 1986-December 1988  

SciTech Connect

A physiologically based pharmacokinetic (PB-PK) model was developed to describe trichloroethylene (TCE) kinetics in the pregnant rat exposed to TCE by inhalation, by bolus gavage, or by oral ingestion in drinking water. The kinetics of trichloroacetic acid (TCA), an oxidative metabolite of TCE, were described by a classical one-compartment pharmacokinetic model. Among the required model parameters for TCE, partition coefficients (PCs) and kinetic constants for oxidation were determined by vial equilibration and gas uptake methods, respectively. The fat:blood PC was 33.9; the blood:air PC was 13.2; and the fetal tissue:fetal blood PC was 0.51. TCE was readily metabolized with high substrate affinity. In naive and pregnant female rats the maximum velocities of oxidative metabolism were 10.98 + 0.155 and 9.18 +/- 0.078 mg/kg/hr, while the estimated Michaelis constant for the two groups of rats was very low, 0.25 mg/liter. The first-order rate constant for oral absorption of TCE from water was 5.4 +/- 0.42/hr-1 in naive rats. With TCA, the volume of distribution (0.618 liter/kg) and the plasma elimination rate constant (0-045 0.0024/hour) were estimated both from intravenous dosing studies with TCA and from an inhalation study with TCE. By comparison of the two routes of administration, the stoichiometric yield of TCA from Pregnancy, Physiologically Based Pharmacokinetic Modeling, Toxicology, Trichloroethylene, Trichloroacetic Acid.

Fisher, J.W.; Whittaker, T.A.; Taylor, D.H.; Clewell, H.J.; Andersen, M.E.



Enhanced thromboxane synthesis during chronic reductions in uterine perfusion pressure in pregnant rats  

Microsoft Academic Search

BackgroundThe purpose of this study was to determine the role of thromboxane A2 (TXA2) in a conscious, chronically instrumented rat model of pregnancy-induced hypertension (PIH) produced by chronic reductions in uterine perfusion pressure (RUPP).

Maria T Llinás; Barbara T Alexander; Mona Seedek; Sean R Abram; Anna Crell; Joey P Granger



Enduring Changes in Dopamine Receptor Cells of Pups from Drug Administration to Pregnant and Nursing Rats  

Microsoft Academic Search

A decrease in specific [3H]spiroperidol binding to rat caudate tissue and a parallel decrease in sensitivity to apomorphine in eliciting stereotyped behavior was observed in the offspring of rat mothers treated with either haloperidol or alpha -methyl-p-tyrosine-methyl ester during pregnancy. In contrast, evidence of increased dopamine-receptor sensitivity was observed in the pups if haloperidol was administered to their mothers postpartum

Helen Rosengarten; Arnold J. Friedhoff



A Low-Affinity Estrogen-Binding Site in Pregnant Rat Uteri: Analysis and Partial Purification  

Microsoft Academic Search

We have identified a low-affinity (type II) estrogen-binding site (EBS) that is expressed at high levels during pregnancy in rat uteri. Although this activity was detectable in nonpregnant rat uteri, it was present in amounts (0.094 pmol\\/g of uteri) that were severalfold lower than the high-affinity type I estrogen receptor (0.57 pmol\\/g of uteri). During pregnancy, at 19-20 days of

Wesley G. N. Gray; Esther E. Biswas; Nasir Bashirelahi; Subhasis B. Biswas



Long-term programming of enhanced aggression by peripuberty stress in female rats.  


Human literature has linked adverse early life experiences with an increased risk to develop violent behaviors in both boys and girls. We have previously shown that male rats submitted to stress during the peripuberty period display as adults abnormal aggressive behavior against both male intruders and female partners. In the present study, we examined whether the same stress protocol would affect the development of aggressive behaviors in female rats. We evaluated the behavior of these peripuberty stressed female rats when confronted, at adulthood, with either female or male intruders, and during their cohabitation with male partners. Given that estrus cycle influences mood and aggressive behaviors, female aggressive behavior was assessed at different estrus cycle phases: estrus and diestrus, and during pregnancy and lactancy. Additionally, we evaluated postpartum plasma levels of vasopressin, oxytocin and corticosterone, hormones associated with aggression and the regulation of social behavior. Compared to control females, females submitted to stressful events during puberty exhibited higher and more sustained rates of aggression during adulthood independently on the estrus cycle or the sex of the intruder, and they had higher levels of plasma vasopressin. Significant correlations between plasma levels of vasopressin and corticosterone and aggressive behavior were also found. Strikingly, our results showed opposite intragroup correlations suggesting a different role of these hormones on aggression depending on life experiences. We provide here an animal model, devoid of cultural influences strongly supporting a role for biological factors in the development of aggressive behaviors following exposure to stressful events at puberty in females. PMID:23942011

Cordero, M Isabel; Ansermet, François; Sandi, Carmen



Reproductive status and testosterone among females in cooperative mole-rat societies.  


Sexual selection acts on traits that increase reproductive success. Variation in reproductive success is often higher among males than females. Consequently, sexual selection has been studied extensively in males while its possible role in females has only recently attracted considerable attention. In some cooperatively breeding species females compete intensely for reproductive opportunities and may thereby have evolved 'male-like' traits such as increased intra-sexual aggression and exaggerated secondary sexual traits. The expression of the latter tends to be testosterone-dependent in male vertebrates but whether this is also the case among females remains poorly understood. Here, we compare two cooperatively breeding mole-rat species (Natal, Cryptomys hottentotus natalensis, and Damaraland mole-rats, Fukomys damarensis) in which a single female monopolises reproduction through behavioural and physiological suppression, respectively, to evaluate the effect of female intra-sexual competition. Consistent with the hypothesis that intra-sexual competition has shaped patterns of testosterone (T) secretion among females in these species, we show that (i) female T levels in both species are significantly higher among breeding (BFs) (who may face the highest degree of intra-sexual competition) compared to non-breeding females (NBFs), (ii) that T levels in both species are significantly higher when access to unrelated males can be assumed to be greatest (i.e., wet season), and (iii) that the average female T levels are a full order of magnitude higher in the absence of a physiological mechanism of reproductive suppression. Together, our results suggest a role for intra-sexual competition in shaping patterns of T secretion among females of the social mole-rats and raise the possibility of a modulatory role for the mode of reproductive suppression on competition-related traits in females. PMID:23583770

Lutermann, Heike; Young, Andrew J; Bennett, Nigel C



Paradoxical air embolism through patent foramen ovale during consensual intercourse in a non-pregnant young female.  


Sudden vaginal bleeding and a cardiac arrest occurred in a 18-year-old female during consensual intercourse. Resuscitation procedures, applied at the arrival of a medical emergency team, restored the cardiac function allowing admission to hospital, where two vaginal mucosal lacerations were diagnosed and sutured. Cardiological investigations diagnosed a left ventricle myocardial infarction and a patent foramen ovale while a brain CT scan showed ischemic signs and intravascular air images. Death occurred after 48 h, due to heart failure, cerebral anoxia and multiorgan failure. Autopsy confirmed a patent foramen ovale considered as responsible for a paradoxical air embolism. Judicial Authority evaluated the fatal paradoxical air embolism as a consequence of an unpredictable accident occurred during consensual intercourse without sexual violence. PMID:19782322

Moreschi, Carlo; Da Broi, Ugo



Development of multi-route physiologically-based pharmacokinetic models for ethanol in the adult, pregnant, and neonatal rat.  


Biofuel blends of 10% ethanol (EtOH) and gasoline are common in the USA, and higher EtOH concentrations are being considered (15-85%). Currently, no physiologically-based pharmacokinetic (PBPK) models are available to describe the kinetics of EtOH-based biofuels. PBPK models were developed to describe life-stage differences in the kinetics of EtOH alone in adult, pregnant, and neonatal rats for inhalation, oral, and intravenous routes of exposure, using data available in the open literature. Whereas ample data exist from gavage and intravenous routes of exposure, kinetic data from inhalation exposures are limited, particularly at concentrations producing blood and target tissue concentrations associated with developmental neurotoxicity. Compared to available data, the three models reported in this paper accurately predicted the kinetics of EtOH, including the absorption, peak concentration, and clearance across multiple datasets. In general, model predictions for adult and pregnant animals matched inhalation and intravenous datasets better than gavage data. The adult model was initially better able to predict the time-course of blood concentrations than was the neonatal model. However, after accounting for age-related changes in gastric uptake using the calibrated neonate model, simulations consistently reproduced the early kinetic behavior in blood. This work provides comprehensive multi-route life-stage models of EtOH pharmacokinetics and represents a first step in development of models for use with gasoline-EtOH blends, with additional potential applicability in investigation of the pharmacokinetics of EtOH abuse, addiction, and toxicity. PMID:22954395

Martin, Sheppard A; McLanahan, Eva D; El-Masri, Hisham; LeFew, William R; Bushnell, Philip J; Boyes, William K; Choi, Kyoungju; Clewell, Harvey J; Campbell, Jerry L



GH binding to liver in young and old female rats: relation to somatomedin-C secretion  

SciTech Connect

Age-related changes in binding of /sup 125/I-bovine GH to liver membrane fractions were measured in female Long-Evans rats 2, 6, 12, and 20 months of age. Specific GH binding did not change between 2 and 6 months of age but increased significantly at 12 and 20 months of age. Scatchard analyses showed that the plots were curvilinear and consisted of high- and low-affinity binding sites. The age-related increases in binding sites were mainly due to an increase in number of low-affinity binding sites. Serum somatomedim-C (SM-C) levels in 20-month-old rats were about half those in the 6-month-old rats. Twice daily injections of ovine GH (2 mg/kg body wt) for 7 days depressed liver GH binding and increased serum SM-C levels in 19-month-old female rats, but had no effect on GH binding in 2-month-old female rats. These results suggest that the increase in liver GH binding sites and the decrease in SM-C secretion are associated with our previously reported decrease in GH secretion in old female rats.

Takahashi, S.; Meites, J.



Individual differences in psychostimulant responses of female rats are associated with ovarian hormones and dopamine neuroanatomy  

PubMed Central

Ovarian hormones modulate the pharmacological effects of psychostimulants and may enhance vulnerability to drug addiction. Female rats have more midbrain dopamine neurons than males and greater dopamine uptake and release rates. Cocaine stimulates motor behavior and dopamine efflux more in female than male rats, but the mediating mechanisms are unknown. This study investigated individual differences in anatomic, neurochemical, and behavioral measures in female rats to understand how ovarian hormones affect the relatedness of these endpoints. Ovarian hormone effects were assessed by comparing individual responses in ovariectomized (OVX) and sham adult female rats. Locomotion was determined before and following 10 mg/kg cocaine. Electrically-stimulated dopamine efflux was assessed using fast cyclic voltammetry in vivo. Dopamine neuron number and density in substantia nigra (SN) and ventral tegmental area (VTA) were determined in the same animals using tyrosine-hydroxylase immunohistochemistry and unbiased stereology. Locomotor behavior and dopamine efflux did not differ at baseline but were greater in sham than OVX following cocaine. Cocaine increased dopamine release rates in both groups but uptake inhibition (Km) was greater in sham than OVX. Dopamine neuron number and density in SN and VTA were greater in shams. Sham females with the largest uterine weights exhibited the highest density of dopamine neurons in the SN, and the most cocaine-stimulated behavior and dopamine efflux. Ovariectomy eliminated these relationships. We postulate that SN density could link ovarian hormones and high-psychostimulant responses in females. Similar mechanisms may be involved in individual differences in the addiction vulnerability of women.

Walker, Q. David; Johnson, Misha L.; Van Swearingen, Amanda E.D.; Arrant, Andrew E.; Caster, Joseph M.; Kuhn, Cynthia M.



Effects of pretraining and water temperature on female rats' performance in the Morris water maze.  


The water maze is a complex spatial task that requires the coordination of multiple systems to perform efficiently. Various factors have been shown to influence performance in this task, including motivational state and prior experience. Although a consistent sex difference has been observed in acquiring the water maze in rats, the contribution of the various factors in female rat performance has not been fully assessed. Therefore, the current study tested the effects of motivation as manipulated by water temperature of the maze and prior experience in the maze on the performance of female rats. It was hypothesized that females pretrained in the maze would perform better than those without exposure to the water maze, regardless of water temperature, but in naïve rats, colder water would improve performance as shown previously in male rats. For pretraining, female rats were taught to find a visible platform in cold (19°C, 4 trials on one day) and warm (25°C, 4 trials on one day) water before acquisition trials, with the order of the water temperature randomly assigned. Control rats were not given any training and were naïve to the water maze procedure. Pretrained and control rats were then tested to locate a hidden platform in either cold or warm water for 5 consecutive days. Overall, pretraining had a significant effect on distance, latency, and directness of path to the platform. Water temperature did not show a significant effect on any measure or a significant interaction with pretraining. Thus, while our hypothesis that pretraining would improve performance was supported, the results did not support the prediction that water temperature would also significantly influence performance. These results show that non-spatial pretraining can critically improve the performance of females in acquiring a place strategy for the hidden platform, irrespective of water temperature. PMID:23624154

Anderson, E M; Moenk, M D; Barbaro, L; Clarke, D A; Matuszewich, 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.



Passive smoke exposure of female rats caused aortic atherosclerotic precursor lesions in their offspring.  


The aim of this study was to evaluate the presence and degree of preclinical atherosclerosis in pups of pregnant rats exposed to cigarette smoke. Abdominal aorta examined for atherosclerotic lesions and intimal medial thickness of the abdominal aorta was measured by image analysis. The study groups showed endothelial cellular losses, marked intimal injuries, elastic fiber damages, mononuclear cellular infiltration, and irregularities in internal elastic membrane, with pronounced damages as integrity losses and local fragmentations. The results provide evidence for development of an atherosclerotic process in the neonatal period, even in prenatal stage, long before the formation of smoke-related cardiovascular diseases. PMID:22413908

Tunc, Turan; Sarici, Umit; Aydinoz, Secil; Onguru, Onder; Karaoglu, Abdulbaki; Uysal, Bulent; Kul, Mustafa; Sirin, Yusuf Sinan; Oztas, Emin; Yaman, Halil



Dietary Soy Supplements Produce Opposite Effects on Anxiety in Intact Male and Female Rats in the Elevated Plus-Maze  

Microsoft Academic Search

The effects of 2 popular, commercially available soy phytoestrogen supplements on anxiety in male, diestrus female, and proestrus female rats were examined with an elevated plus-maze. Both of the soy supplements were anxiolytic in proestrus females but anxiogenic in males as determined by time spent in the open arms. No effect of diet was seen in the diestrus females. The

Heather B. Patisaul; Adele Blum; Jordan R. Luskin; Mark E. Wilson



Chronic stress effects on the apoptotic index of the adrenal cortex of pregnant rats  

Microsoft Academic Search

Chronic stress by immobilization during gestation can alter several mechanisms that maintain homeostasis in adrenal gland. The aim of this work was to quantify the apoptotic index of adrenal cortex during mid-pregnancy and to prove cytological characteristics by electron microscopy. The apoptotic index did not present significant differences between the adrenal cortex areas of control and experimental rats in any



Middle-aged female rats retain sensitivity to the anorexigenic effect of exogenous estradiol  

PubMed Central

It is well established that estradiol (E2) decreases food intake and body weight in young female rats. However, it is not clear if female rats retain responsiveness to the anorexigenic effect of E2 during middle age. Because middle-aged females exhibit reduced responsiveness to E2, manifesting as a delayed and attenuated luteinizing hormone surge, it is plausible that middle-aged rats are less responsive to the anorexigenic effect of E2. To test this we monitored food intake in ovariohysterectomized young and middle-aged rats following E2 treatment. E2 decreased food intake and body weight to a similar degree in both young and middle-aged rats. Next, we investigated whether genes that mediate the estrogenic inhibition of food intake are similarly responsive to E2 by measuring gene expression of the anorexigenic genes corticotropin-releasing hormone (CRH), proopiomelanocortin (POMC), the long form of the leptin receptor (Lepr) and serotonin 2C receptors (5HT2CR) and the orexigenic genes agouti-related peptide (AgRP), neuropeptide Y (NPY), prepromelanin-concentrating hormone (pMCH) and orexin in the hypothalamus of young and middle-aged OVX rats treated with E2. As expected, E2 increased expression of all anorexigenic genes while decreasing expression of all orexigenic genes in young rats. Although CRH, 5HT2CR, Lepr, AgRP, NPY and orexin were also sensitive to E2 treatment in middle-aged rats, POMC and pMCH expression were not influenced by E2 in middle-aged rats. These data demonstrate that young and middle-aged rats are similarly sensitive to the anorexigenic effect of E2 and that most, but not all feeding-related genes retain sensitivity to E2.

Santollo, Jessica; Yao, Dachun; Neal-Perry, Genevieve; Etgen, Anne M.



Fluctuations in selenium status during the female rat estrous cycle  

Microsoft Academic Search

A suggested relationship between selenium (Se) status and sex hormones is based on sex-linked differences in Se status of the liver and dramatic changes in Se status during pregnancy. The effect of estrous cycle hormone fluctuation on Se status was studied in the chronically-catheterized rat model. Se status, measured as plasma and RBC Se and glutathione peroxidase activity (GPx), was

C. Cha; A. M. Smith; R. E. Kimura



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


Melatonin Receptor Signaling in Pregnant and Nonpregnant Rat Uterine Myocytes as Probed by Large Conductance Ca2+Activated K+ Channel Activity  

Microsoft Academic Search

The mRNAs of MT1 and MT2 melatonin receptors are present in cells from nonpregnant (NPM) and pregnant (PM) rat myometrium. To investigate the coupling of melatonin receptors to Gq- and Gi-type of heterotrimeric G proteins, we analyzed the ac- tivity of large-conductance Ca2-activated K (BKCa) channels, the expression of which in the uterus is confined to smooth muscle cells. The




Ovarian hormones modulate ‘compulsive’ lever-pressing in female rats  

Microsoft Academic Search

Life events related to the female hormonal cycle may trigger the onset of obsessive–compulsive disorder (OCD) or exacerbate symptoms in women already suffering from it. These observations suggest a possible role for ovarian hormones in the course of this disorder. Yet, the mechanisms that may subserve the modulatory effect of ovarian hormones are currently unknown. The aim of the present

Shlomit Flaisher-Grinberg; Noa Albelda; Liron Gitter; Keren Weltman; Michal Arad; Daphna Joel



Luteinizing hormone-releasing hormone (LHRH) neurons in the male and female rats at peripubertal period  

Microsoft Academic Search

Luteinizing hormone-releasing hormone (LHRH) neurons were immunohistochemically studied in rats of both sexes at peripubertal ages. The number of immunoreactive LHRH neurons (irLHRH neurons) was counted in the brain region from the level of the septumpreoptic area to the level of the rostral part of the infundibulum in colchicine-treated male and female rats at 30 and 60 days of age.

Sumio Takahashi; Reiko Ono; Kouji Nomura; Seiichiro Kawashima



Effect of Estradiol and Progesterone Treatment on Carbohydrate Metabolizing Enzymes in Tissues of Aging Female Rats  

Microsoft Academic Search

The aim of this study was to determine the effect of administration of estradiol (E2), progesterone (P4), and combination of estradiol and progesterone (EP) in aging female rats. The changes in the activities of hexokinase (HK), glucose-6-phosphatase (G6P?tase) and glucose-6-phosphate dehydrogenase (G6PDH) enzymes, and in protein levels in tissues of rats namely brain (cerebral hemisphere), heart, liver, kidney and uterus

K. Moorthy; Umesh C. S. Yadav; M. R. Siddiqui; D. Sharma; S. F. Basir; N. Z. Baquer



Voluntary running improves glucose tolerance and insulin resistance in female spontaneously hypertensive rats  

Microsoft Academic Search

We evaluated the effects of voluntary exercise training on glucose metabolism and measures of insulin sensitivity in female spontaneously hypertensive rats (SHR). Age-matched Wistar-Kyoto rats (WKY) were used as normotensive controls. Exercising SHR were housed in running wheels for 8 weeks (SHRx8) or 16 weeks (SHRx16). At 22 weeks of age, we measured systolic blood pressure, performed oral glucose tolerance

Tanya L. Kinney LaPier; Arthur L. M. Swislocki; Raymond J. Clark; Kenneth J. Rodnick



Effects of Nicotine on Bone Mass, Turnover, and Strength in Adult Female Rats  

Microsoft Academic Search

This study investigated the effects of nicotine, the chemical responsible for tobacco addiction, on bone and on serum mineral and calcitropic hormone levels in adult, female rats to help resolve a current controversy regarding the impact of nicotine on bone health. Seven-month-old rats received either saline (n = 12), low-dose nicotine (4.5 mg\\/kg\\/day, n = 2), or high-dose nicotine (6.0

U. T. Iwaniec; Y. K. Fung; M. P. Akhter; M. C. Haven; S. Nespor; G. R. Haynatzki; D. M. Cullen



Reproductive effects in male and female rats of neonatal exposure to genistein  

Microsoft Academic Search

Sprague-Dawley rats were administered genistein orally at doses of 12.5, 25, 50, or 100 mg\\/kg on postnatal days 1 through 5 to examine its effects on reproductive function after puberty. In addition, preputial separation and vaginal opening as endpoints of sexual maturation, estrous cycling, sperm count, serum testosterone concentration, and histopathologic changes of reproductive organs of male and female rats

Tetsuji Nagao; Shinsuke Yoshimura; Yoshiaki Saito; Madoka Nakagomi; Kenji Usumi; Hiroshi Ono



Perinatal Exposure to the Estrogenic Pollutant Bisphenol A Affects Behavior in Male and Female Rats  

Microsoft Academic Search

FARABOLLINI F., S. PORRINI, AND F. DESSÌ-FULGHERI. Perinatal exposure to the estrogenic pollutant Bisphenol A affects behavior in male and female rats. PHARMACOL BIOCHEM BEHAV 64(4) 687–694, 1999.—Bisphenol A (BPA) is an environmental estrogen with potentially aversive effects on public health. In rats, we studied the effects of perinatal exposure to BPA on nonsocial behaviors partly influenced by gonadal hormones.

F Farabollini; S Porrini



Factors influencing aggression toward females by male rats exposed to anabolic androgenic steroids during puberty  

Microsoft Academic Search

Previous results showed that male rats pubertally exposed to anabolic androgenic steroids (AAS) displayed aggression towards females in response to physical provocation. This experiment examined two factors that may modulate AAS-induced behavior towards females: olfactory cues and frustration. Gonadally intact males began one of three AAS treatments at puberty (D40): testosterone propionate (T), stanozolol (S), T+S, or vehicle control. To

Rebecca L. Cunningham; Marilyn Y. McGinnis



Correction of Endothelial Dysfunction in Diabetic Female Rats by Tetrahydrobiopterin and Chronic Insulin  

Microsoft Academic Search

Diabetes-induced vascular dysfunction has mainly been studied in males. However, the mechanisms involved may not correspond to those in females. Here we analyzed the effects of tetrahydrobiopterin (BH4) and chronic insulin on the physiology of mesenteric arterioles of alloxan-diabetic female rats. The parameters studied were the mesenteric arteriolar reactivity (intravital microscopy), nitric oxide synthase (NOS) activity (conversion of L-arginine to

Eliana H. Akamine; Elisa M. Kawamoto; Cristoforo Scavone; Dorothy Nigro; Maria Helena C. Carvalho; Rita de Cássia A. Tostes; Luiz R. G. Britto; Zuleica B. Fortes



Is gender crucial for cardiovascular adjustments induced by exercise training in female spontaneously hypertensive rats?  


Evidence of mild hypertension in women and female rats and our preliminary observation showing that training is not effective to reduce pressure in female as it does in male spontaneously hypertensive rats (SHR) prompt us to investigate the effects of gender on hemodynamic pattern and microcirculatory changes induced by exercise training. Female SHR and normotensive controls (Wistar-Kyoto rats) were submitted to training (55% VO(2) peak; 3 months) or kept sedentary and instrumented for pressure and hindlimb flow measurements at rest and during exercise. Heart, kidney, and skeletal muscles (locomotor/nonlocomotor) were processed for morphometric analysis of arterioles, capillaries, and venules. High pressure in female SHR was accompanied by an increased arteriolar wall:lumen ratio in the kidney (+30%; P<0.01) but an unchanged ratio in the skeletal muscles and myocardium. Female SHR submitted to training did not exhibit further changes on the arteriolar wall:lumen ratio and pressure, showing additionally increased hindlimb resistance at rest (+29%; P<0.05). On the other hand, female SHR submitted to training exhibited increased capillary and venular densities in locomotor muscles (+50% and 2.3-fold versus sedentary SHR, respectively) and normalized hindlimb flow during exercise hyperemia. Left ventricle pressure and weight were higher in SHR versus WKY rats, but heart performance (positive dP/dt(max) and negative dP/dt(max)) was not changed by hypertension or training, suggesting a compensated heart function in female SHR. In conclusion, the absence of training-induced structural changes on skeletal muscle and myocardium arterioles differed from changes observed previously in male SHR, suggesting a gender effect. This effect might contribute to the lack of pressure fall in trained female SHRs. PMID:18695147

Coimbra, Rosemeire; Sanchez, Lylian S; Potenza, Janaina M; Rossoni, Luciana V; Amaral, Sandra Lia; Michelini, Lisete C



Diabetes Reduces Growth and Body Composition More in Male Than in Female Rats  

Microsoft Academic Search

Food restriction and\\/or starvation has a consistently greater and more permanent effect on physical growth in males than in females. Because diabetes may be viewed as being analogous to starvation, we tested the hypothesis that diabetes would reduce growth more in male than in female rats. Diabetes was induced with streptozotocin (65–125 mg\\/kg IP) at 3 weeks of age in




Exposure to repeated maternal aggression induces depressive-like behavior and increases startle in adult female rats.  


The stress response is a multifaceted physiological reaction that engages a wide range of systems. Animal studies examining stress and the stress response employ diverse methods as stressors. While many of these stressors are capable of inducing a stress response in animals, a need exists for an ethologically relevant stressor for female rats. The purpose of the current study was to use an ethologically relevant social stressor to induce behavioral alterations in adult female rats. Adult (postnatal day 90) female Wistar rats were repeatedly exposed to lactating Long Evans female rats to simulate chronic stress. After six days of sessions, intruder females exposed to defeat were tested in the sucrose consumption test, the forced swim test, acoustic startle test, elevated plus maze, and open field test. At the conclusion of behavioral testing, animals were restrained for 30 min and trunk blood was collected for assessment of serum hormones. Female rats exposed to maternal aggression exhibited decreased sucrose consumption, and impaired coping behavior in the forced swim test. Additionally, female rats exposed to repeated maternal aggression exhibited an increased acoustic startle response. No changes were observed in female rats in the elevated plus maze or open field test. Serum hormones were unaltered due to repeated exposure to maternal aggression. These data indicate the importance of the social experience in the development of stress-related behaviors: an acerbic social experience in female rats precipitates the manifestation of depressive-like behaviors and an enhanced startle response. PMID:22093902

Bourke, Chase H; Neigh, Gretchen N



Exposure to repeated maternal aggression induces depressive-like behavior and increases startle in adult female rats  

PubMed Central

The stress response is a multifaceted physiological reaction that engages a wide range of systems. Animal studies examining stress and the stress response employ diverse methods as stressors. While many of these stressors are capable of inducing a stress response in animals, a need exists for an ethologically relevant stressor for female rats. The purpose of the current study was to use an ethologically relevant social stressor to induce behavioral alterations in adult female rats. Adult (postnatal day 90) female Wistar rats were repeatedly exposed to lactating Long Evans female rats to simulate chronic stress. After six days of sessions, intruder females exposed to defeat were tested in the sucrose consumption test, the forced swim test, acoustic startle test, elevated plus maze, and open field test. At the conclusion of behavioral testing, animals were restrained for 30 minutes and trunk blood was collected for assessment of serum hormones. Female rats exposed to maternal aggression exhibited decreased sucrose consumption, and impaired coping behavior in the forced swim test. Additionally, female rats exposed to repeated maternal aggression exhibited an increased acoustic startle response. No changes were observed in female rats in the elevated plus maze or open field test. Serum hormones were unaltered due to repeated exposure to maternal aggression. These data indicate the importance of the social experience in the development of stress-related behaviors: an acerbic social experience in female rats precipitates the manifestation of depressive-like behaviors and an enhanced startle response.

Bourke, Chase H.; Neigh, Gretchen N.



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



Effects of hypothyroidism on mammary and liver lipid metabolism in virgin and late-pregnant rats  

Microsoft Academic Search

Untreated maternal hypothyroidism (hypoT) has serious consequences in offspring development that may result from the effect on lactation of maternal metabolism dysfunction. We studied the effects of prolonged propyl- thiouracyl (PTU)-induced hypoT (0.1% PTU in drinking wa- ter starting 8 days before mating until day 21 of pregnancy or for 30 days in virgin rats) on liver and mammary lipid

María Belén Hapon; Silvia M. Varas; Graciela A. Jahn; María S. Giménez



Enhanced utilization of glycerol for glyceride synthesis in isolated adipocytes from early pregnant rats  

Microsoft Academic Search

Adipose tissue normally has low glycerol kinase activity, but its expression is enhanced under conditions of augmented insulin\\u000a sensitivity and\\/or obesity. Since these conditions occur during early pregnancy, the comparative utilization of glucose or\\u000a glycerol by isolated adipocytes from rats at 0, 7, 14, or 20 days of pregnancy was studied. Incubations were carried out in\\u000a the presence of [U14C]-glucose or

Emilio Herrera; Sonia del Campo; Justyna Marciniak; Julio Sevillano; Maria Pilar Ramos



Effects of Brain Antiestrogen Implants on Maternal Behavior and on Postpartum Estrus in Pregnant Rats  

Microsoft Academic Search

To test the hypothesis that the onset of maternal behavior is stimulated by estrogen, we examined the effects of medial preoptic area (MPOA) or ventromedial hypothalamus (VMH) implants of the antiestrogen 4-hydroxytamoxifen (OH-TAM) on pre- and postpartum maternal behavior and on postpartum estrus in rats. On day 20 of pregnancy, animals were implanted bilaterally with OH-TAM or cholesterol cannulae into

Harry B. Ahdieh; Anne D. Mayer; Jay S. Rosenblatt



2Methoxyestradiol Inhibits Longitudinal Bone Growth in Normal Female Rats  

Microsoft Academic Search

.   2-Methoxyestradiol (2-MeO-E2), a major metabolite of 17?-estradiol, may function as a physiological tumor suppressor and is being investigated for clinical\\u000a applications. It has been reported to target rapidly dividing cells. We investigated the effects of 2-MeO-E2 on the growth plate of young rats because normal longitudinal bone growth requires rapid proliferation of cartilage and endothelial\\u000a cells. Sexually mature (3-month-old)

R. T. Turner; G. L. Evans



Effects of ibuprofen on the disposition kinetics of phenytoin in pregnant rats.  


The effects of ibuprofen on maternal phenytoin pharmacokinetics and fetal phenytoin acquisition were investigated in 19-day gestation Sprague-Dawley rats. A 5 mg kg-1 bolus injection of 14C-phenytoin was given with and without (control) pretreatment with 12.5 mg kg-1 of ibuprofen. Maternal plasma and fetal whole body samples were obtained at various times after the phenytoin bolus and evaluated simultaneously using a three-compartment maternal-fetal model. Ibuprofen pretreatment increased the maternal plasma clearance of phenytoin about three-fold and the overall apparent volume of distribution almost four-fold. No changes in the volume of the maternal central compartment or terminal first-order disposition rate constant were observed. Additionally, the maternal-to-fetal clearance of phenytoin was not altered in the ibuprofen-treated rats. No differences in the apparent fetal volume of distribution or areas under the fetal phenytoin concentration-time curves were observed between the control and ibuprofen-treated rats. The results of this study were consistent with ibuprofen-induced alterations in organ and tissue blood perfusion and demonstrated that, while the maternal disposition kinetics of phenytoin were altered by sodium ibuprofen coadministration, the maternal changes did not affect the extent of fetal exposure to phenytoin. PMID:4005395

Cleveland, P A; Ueda, C T


Embryotoxicity and fetotoxicity following intraperitoneal administrations of hexavalent chromium to pregnant rats.  


Heavy metals are omnipresent in the environment, and industrial use has greatly increased their presence in soil, water and air. Their inevitable transfer to the human food chain remains an important environmental issue as many heavy metals cause a range of toxic effects, including developmental toxicity. Administration of chromium VI (1 and 2 mg/kg as potassium dichromate) through intraperitoneal (i.p.) injection during organogenesis (days 6 to 15 of gestation) in rats revealed embryo- and fetotoxic effects. Reduced fetal weight, retarded fetal development, number of fetuses per mother and high incidences of dead fetuses and resorptions in treated mothers were also observed. Gross morphological abnormalities, such as displayed form of edema, facial defect, lack of tail, hypotrophy, severs subdermal haemorrhage patches and hypotrophy of placenta were observed in fetuses after chromium VI-treated mothers. A skeletal development of fetuses presented an incomplete ossification in nasal, cranium, abdominal or caudal bones in rats treated with 1 mg/kg of chromium, whereas rats treated with 2 mg/kg showed ossification and absence of the sacral vertebrae compared with the control. At a higher dose of chromium, histological changes were found in fetuses with atrophy of theirs vital organs. Placental histological observations revealed a pronounced morphological alteration, with atrophy of decidual cells, a degenerated of chorionic villi and hypertrophy of blood lacuna. The present study suggests a risk to the developing embryo when the mother is exposed to a high concentration of chromium VI during organogenesis. PMID:21205386

Marouani, Neila; Tebourbi, Olfa; Mokni, Moncef; Yacoubi, Mohamed Tahar; Sakly, Mohsen; Benkhalifa, Moncef; Ben Rhouma, Khémais



Stress during adolescence enhances locomotor sensitization to nicotine in adulthood in female, but not male, rats.  


A wide body of research has indicated that perinatal exposure to stressors alters the organism, notably by programming behavioral and neuroendocrine responses and sensitivity to drugs of abuse in adulthood. Recent evidence suggests that adolescence also may represent a sensitive period of brain development, and yet there has been little research on the long-lasting effects of stressors during this period. We investigated the effects of pubertal social stress (PS; daily 1-h isolation followed by pairing with a new cage mate on postnatal days 33-48) on locomotor sensitization to injections of nicotine and corticosterone response to restraint stress when the rats were adults (approximately 3 weeks after PS). There were no differences among the groups in locomotor activity to injections of saline. However, PS females had enhanced locomotor sensitization to repeated doses of nicotine compared to control (non-stressed; NS) females, whereas PS males and NS males did not differ. PS enhanced the corticosterone response to restraint in male rats previously sensitized to nicotine and decreased the corticosterone response in nonsensitized male rats. In contrast, PS females and NS females did not differ in plasma corticosterone levels in response to restraint stress, but NS females showed enhanced corticosterone release to restraint after sensitization to nicotine. Thus, during adolescence, social stressors can have long-lasting effects, and the effects appear to differ for males and females. PMID:15465532

McCormick, Cheryl M; Robarts, Dan; Gleason, Erin; Kelsey, John E



Kinetics of selected di-n-butyl phthalate metabolites and fetal testosterone following repeated and single administration in pregnant rats.  


Human exposure to phthalic acid diesters occurs through a variety of pathways as a result of their widespread use in consumer products and plastics. Repeated doses of di-n-butyl phthalate (DBP) from gestation day (GD) 12 to 19 disrupt testosterone synthesis and male sexual development in the fetal rat. Currently little is known about the disposition of DBP metabolites, such as monobutyl phthalate (MBP) and its glucuronide conjugate (MBP-G), during gestation after repeated exposure to DBP. In order to gain a better understanding of the effect of repeated dosing on maternal and fetal metabolism and distribution, pregnant Sprague-Dawley rats were given a single dose of 500 mg/kg DBP on GD 19 or daily doses of 50, 100, and 500 mg/(kg day) from GD 12 to 19 via corn oil gavage. Dose-response evaluation revealed a non-linear increase in maternal and fetal plasma concentrations of MBP. Maternal and fetal MBP levels were slightly lower in animals after 8 days of dosing at 500 mg/(kg day). Fetal plasma MBP levels closely followed maternal plasma, while the appearance and elimination of MBP-G in fetal plasma were significantly delayed. MBP-G accumulated over time in the amniotic fluid. Inhibition of testosterone was rapid in fetal testes when exposed to DBP (500 mg/(kg day)) on GD 19. Within 24h, the level of inhibition in the fetus was similar between animals exposed to a single or multiple daily doses of 500 mg/(kg day). Examination of testosterone time-course data indicates a rapid recovery to normal levels within 24h post-dosing at DBP doses of 50 and 100 mg/(kg day), with a rebound to higher than normal concentrations at later time-points. MBP kinetics in fetal testes allows direct comparison of active metabolite concentrations and testosterone response in the fetal testes. PMID:19010379

Clewell, Rebecca A; Kremer, John J; Williams, Carla C; Campbell, Jerry L; Sochaski, Mark A; Andersen, Melvin E; Borghoff, Susan J



Evaluation of sex difference in tissue repair following acute carbon tetrachloride toxicity in male and female Sprague-Dawley rats.  


Cellular regeneration and tissue repair greatly influence the outcome of acute carbon tetrachloride (CCl4) hepatotoxicity. This study examined the temporal kinetics of cellular regeneration and tissue repair processes in male and female Sprague Dawley (SD) rats following an acute CCl4 exposure (0.8 ml/kg, i.p.). In female rats, hepatic damage peaked at 24 h following the treatment and was approximately 2.5-fold (AST 2.7-fold, ALT 2.3 fold) greater than the damage observed in male rats. The hepatic damage in male rats appeared to peak by 3 h post-exposure and did not significantly change through the 36-h time-point. The activity of cytochrome P 4502E1 was 20% greater in male rats and did not correlate with the magnitude of hepatic damage. Morphometric analysis of cell cycle indices revealed that cellular regeneration was significantly greater in female rats as compared to male rats at 48 h and corresponded proportionally to the extent of liver damage. This study demonstrated that female SD rats respond more severely to acute CCl4 hepatotoxicity than male SD rats and the extent of tissue repair and cellular regeneration was greater in female rats. Furthermore, our results suggest that tissue repair is unlikely to result in accounting for the different responses exhibited by male and female SD rats to CCl4 hepatotoxicity. PMID:9865477

Moghaddam, A P; Eggers, J S; Calabrese, E J



Effect of restricted food supply to pregnant rats inhaling carbon monoxide on fetal weight, compared with cigarette smoke exposure  

SciTech Connect

Although many studies have shown that cigarette smoking during gestation retarded the intrauterine fetal growth, resulting in the decreased birth weight in babies born to smoking mothers, neither causal substance nor mechanism of action to disturb fetal growth has been firmly established yet. Based on the human and animal studies, researchers have implied that fetal hypoxia induced by carbon monoxide (CO) in the cigarette smoke to be responsible for the event. A shortage in energy intake in smoking mothers also has been suspected to cause the retardation in fetal development. In the previous results (Tachi and Aoyama 1983), the weight increment in CO exposed animals was greater than that in the smoke exposed group. The phenomenon seemed to indicate that the reduction in the food intake occurs in animals which inhale the cigarette smoke, and induces the disturbance of fetal development in association with CO. In the present study, so as to evaluate the role of energy intake upon the fetal development in utero, the experiment of paired feeding with pregnant rats exposed to cigarette smoke is designed in animals which inhale the cigarette smoke, CO, or room air, following after the observation of the quantity of food taken by mothers exposed to cigarette smoke, CO, or room air.

Tachi, N.; Aoyama, M.



Exercise pressor reflex function in female rats fluctuates with the estrous cycle.  


In women, sympathoexcitation during static handgrip exercise is reduced during the follicular phase of the ovarian cycle compared with the menstrual phase. Previous animal studies have demonstrated that estrogen modulates the exercise pressor reflex, a sympathoexcitatory mechanism originating in contracting skeletal muscle. The present study was conducted in female rats to determine whether skeletal muscle contraction-evoked reflex sympathoexcitation fluctuates with the estrous cycle. The estrous cycle was judged by vaginal smear. Plasma concentrations of estrogen were significantly (P < 0.05) higher in rats during the proestrus phase of the estrus cycle than those during the diestrus phase. In decerebrate rats, either electrically induced 30-s continuous static contraction of the hindlimb muscle or 30-s passive stretch of Achilles tendon (a maneuver that selectively stimulates mechanically sensitive muscle afferents) evoked less renal sympathoexcitatory and pressor responses in the proestrus animals than in the diestrus animals. Renal sympathoexcitatory response to 1-min intermittent (1- to 4-s stimulation to relaxation) bouts of static contraction was also significantly less in the proestrus rats than that in the diestrus rats. In ovariectomized female rats, 17?-estradiol applied into a well covering the dorsal surface of the lumbar spinal cord significantly reduced skeletal muscle contraction-evoked responses. These observations demonstrate that the exercise pressor reflex function and its mechanical component fluctuate with the estrous cycle in rats. Estrogen may cause these fluctuations through its attenuating effects on the spinal component of the reflex arc. PMID:22723635

Koba, Satoshi; Yoshinaga, Kenshi; Fujita, Sayaka; Miyoshi, Michio; Watanabe, Tatsuo



U-69593, a Kappa Opioid Receptor Agonist, Decreases Cocaine-Induced Behavioral Sensitization in Female Rats  

PubMed Central

This study was designed to investigate if the kappa opioid system regulates the locomotor response to cocaine in the female rat and to determine if the effect is dependent on estradiol treatment. Adult rats were ovariectomized (OVX) and half received an estradiol (OVX-EB) implant. After a week, rats were injected for 5 consecutive days with vehicle or with the KOPr agonist U-69593 (0.16 mg/kg, 0.32 mg/kg, 0.64 mg/kg) 15 min prior to cocaine injection (15 mg/kg). Following a 7 day drug free period, rats were challenged with cocaine (Day 13). The locomotor response to cocaine was measured on days 1, 5 and 13. U-69593 (0.32 mg/kg) decreased cocaine-induced locomotor activity in drug naïve OVX and OVX-EB rats. These results indicate that the acute effects of U-69593 are independent of estradiol treatment. Repeated exposure to U-69593 (0.32 mg/kg) prior to cocaine decreased the development of behavioral sensitization in OVX-EB rats. This decrease in cocaine-induced hyperlocomotion persisted after one week of cocaine withdrawal. These data indicate that the KOPr system participates in estradiol modulation of cocaine-induced behavioral sensitization in the female rat.

Puig-Ramos, Anabel; Santiago, Gladys S.; Segarra, Annabell C.



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.

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



Effect of isoflavone administration on age-related hepatocyte changes in old ovariectomized femal Wistar rats.  


Aging seems to be due to the accumulation of oxidative damage in cells and molecules. On the other hand, menopause and ovariectomy induce deleterious effects on different organs and systems that have been shown to be counteracted by estrogens and in a not so evident form also with phytoestrogens. The present study has investigated whether the administration of a commercial soy extract that contains approximately 10% isoflavones was able to modify some parameters related to oxidative stress and inflammation in hepatocytes isolated from old ovariectomized female Wistar rats. Eighteen 22-month-old animals that had been previously ovariectomized at 12 months of age were divided into four groups: ovariectomized control rats, estradiol-treated ovariectomized females and ovariectomized rats treated with isoflavones. Six intact female rats of 2 months of age were used as reference group. Hepatocytes were isolated and cultured, and carbon monoxide (CO) and nitric oxide (NO) release, as well as adenosyl triphosphate (ATP), cyclic guanosyl monophosphate (cGMP), phosphatidylcholine (PC) and lipid peroxide (LPO) content of cells were evaluated. Uterus was also removed and weighed. Hepatocytes isolated from old ovariectomized rats showed a decrease in ATP content as compared to young animals. Age also induced an increase in LPO cell content. NO, CO and cGMP were augmented with age, and PC synthesis showed a dramatic reduction. Treatment with either estradiol or isoflavones were able to improve all the mentioned parameters altered in hepatocytes isolated from old ovariectomized rats, and the magnitude of the improvement was similar for both treatments. Ovariectomy induced a significant reduction in uterine weight, which was significantly counteracted by estradiol treatment but not by isoflavone administration. In conclusion, the administration of a soy extract containing isoflavones seems to prevent oxidative changes in hepatocytes isolated from old ovariectomized female rats, without modifying uterus weight. PMID:16785039

Castillo, C; Salazar, V; Ariznavarreta, C; Vara, E; Tresguerres, J A F



Marginal Zinc Deficiency in Pregnant Rats Impairs Bone Matrix Formation and Bone Mineralization in Their Neonates  

Microsoft Academic Search

Zinc (Zn) deficiency during pregnancy may result in a variety of defects in the offspring. We evaluated the influence of marginal\\u000a Zn deficiency during pregnancy on neonatal bone status. Nine-week-old male Sprague-Dawley rats were divided into two groups\\u000a and fed AIN-93G-based experimental diets containing 35 mg Zn\\/kg (Zn adequately supplied, N) or 7 mg Zn\\/kg (low level of Zn,\\u000a L) from 14-day

Masashi Nagata; Megumu Kayanoma; Takeshi Takahashi; Tetsuo Kaneko; Hiroshi Hara



Kappa Opioid-Induced Diuresis in Female vs. Male Rats  

Microsoft Academic Search

? Opioid agonists may produce dissimilar discriminative and analgesic effects in female vs. male subjects. The present study was conducted to determine whether a prototypic physiological effect of ? agonists—diuresis—also differs between the sexes. When data were not corrected for individual differences in body weight, the ? agonists U69,593 (0.03–3.0 mg\\/kg), U50,488 (0.3–10 mg\\/kg), (?)-bremazocine (0.001–0.1 mg\\/kg) and (?)-pentazocine (1–10

Rebecca M Craft; Catherine M Ulibarri; Debra J Raub



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



Combined and individual administration of diethyl phthalate and polychlorinated biphenyls and its toxicity in female Wistar rats  

Microsoft Academic Search

Polychlorinated biphenyls (PCBs) are persistent environmental pollutants and known to act as xenoestrogens. PCBs and diethyl phthalate (DEP) are ubiquitous environmental pollutants because both are used as plasticizers and in various other industrial applications. Therefore, a study was undertaken to evaluate the interactive toxicity of DEP and PCBs in young female Wistar rats. Healthy young female albino rats of Wistar

Contzen Pereira; C. Vaman Rao



Connections Between the Pontine Central Gray and the Ventromedial Hypothalamus Are Essential for Lordosis in Female Rats  

Microsoft Academic Search

Lesions and knife cuts were used to study central gray (CG) and ventromedial hypothalamic (VMH) mediation of sexual receptivity in female rats. Lesions of the midbrain–pontine CG eliminated lordosis in female rats. Bilateral sagittal knife cuts that bracketed the rostral pontine CG also eliminated lordosis, and an experiment with the retrograde tracer Fluoro-Gold confirmed the effectiveness of these cuts in

Ann C. Hennessey; Lael Camak; Frank Gordon; David A. Edwards



Effect of Age on the Accumulation of (131I)Triiodothyronine in Male and Female Rat Brains and Other Tissues.  

National Technical Information Service (NTIS)

Accumulation of (131I)triiodothyronine(T3) by the brain and other tissues in young male and female adult (3 months old) rats was compared with that occurring in old (17 and 24 months) male and female rats. Brain tissues (cerebellum, cerebral white matter,...

D. H. Ford R. K. Rhines




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...


Enhancement of Sexual Behavior in Female Rats by Neonatal Transplantation of Brain Tissue from Males  

NASA Astrophysics Data System (ADS)

Transplantation of preoptic tissue from male rat neonates into the preoptic area of female littermates increased masculine and feminine sexual behavior in the recipients during adulthood. This suggests that functional connections develop between the transplanted neural tissue and the host brain. A new intraparenchymal brain transplantation technique was used to achieve these results.

Arendash, Gary W.; Gorski, Roger A.



Cerebral microgyria, thalamic cell size and auditory temporal processing in male and female rats  

Microsoft Academic Search

Induction of microgyria by freezing injury to the developing somatosensory cortex of neonatal rats causes a defect in fast auditory processing in males, but not in females. It was speculated that early damage to the cortex has sexually dimorphic cascading effects on other brain regions mediating auditory processing, which can lead to the observed behavioral deficits. In the current series

Amy E. Herman; Albert M. Galaburda; R. Holly Fitch; Alex R. Carter; Glenn D. Rosen



Serotonergic projections from the caudal raphe nuclei to the hypoglossal nucleus in male and female rats  

Microsoft Academic Search

The respiratory control system is sexually dimorphic. In many brain regions, including respiratory motor nuclei, serotonin (5HT) levels are higher in females than in males. We hypothesized that there could be sex differences in 5HT input to the hypoglossal nucleus, a region of the brainstem involved in upper airway control. Adult Fischer 344 rats were anesthetized and a retrograde transsynaptic

Jessica R. Barker; Cathy F. Thomas; Mary Behan



Male-female differences in rat hypothalamic-pituitary-adrenal axis responses to nicotine stimulation  

Microsoft Academic Search

Hypothalamic-pituitary-adrenal (HPA) axis responsiveness differs physiologically and pharmacologically between the sexes (sexual diergism). Central nicotinic receptors modulate this endocrine axis. Previous studies have established that nicotine (NIC) stimulates the HPA axis; however, only male animals have been used. We have demonstrated that plasma arginine vasopressin (AVP) and adrenocorticotropic hormone (ACTH) concentrations showed greater responsiveness in male than in female rats

Michael E Rhodes; Susan M O’Toole; R. Kenneth Czambel; Robert T Rubin



Brown-colored deposits on hair of female rats chronically exposed to 60-Hz electric fields  

SciTech Connect

An increased incidence and severity of a brownish coloration of hair has been observed around the nose and on the ears of female rats that were chronically exposed to 60-Hz electric fields. Microscopic examination of the colored areas revealed a red-brown globular deposit on hair shafts in affected areas without signs of physical injury.

Leung, F.C.; Rommereim, D.N.; Miller, R.A.; Anderson, L.E. (Pacific Northwest Laboratory, Richland, WA (USA))



Postnatal handling reduces anxiety as measured by emotionality rating and hyponeophagia tests in female rats  

Microsoft Academic Search

The present studies evaluated the short- and long-lasting effects of postnatal handling (administered during the first 21 days of life) on the emotional behavior of female Sprague-Dawley rats. The performance of postnatally handled (H) and control nonhandled (NH) animals was compared in two different situations: an emotionality rating (ER) test (when they were 40 days or 4 months old), and

Pilar Ferré; Juan Francisco Núñez; Ernesto García; Adolf Tobeña; Rosa Maria Escorihuela; Alberto Fernández-Teruel



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.

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



Chronic restraint stress enhances radial arm maze performance in female rats.  


Effects of chronic restraint stress (21 and 28 days) on physiological and behavioral parameters in female rats were examined. Total (bound and free) and free corticosterone (CORT) levels were measured at different time points during the stress period. Higher total CORT levels were observed in stressed rats during the stress period but returned to baseline at 15 days post-stress. Additionally, free CORT levels decreased across the stress period. Estrous cyclicity was monitored daily in all animals. Stress had no apparent effects on estrous cyclicity, in rats with either normal length or elongated estrous cycles, but stressed females gained less weight than controls. Following the stress period, subjects were tested for open field activity and radial arm maze (RAM) performance. Females stressed for 21 days showed enhanced spatial memory performance on the RAM. A longer period of restraint, 28 days, also led to less weight gain by stressed subjects and unaltered estrous cycle lengths, but was not associated with enhanced RAM performance. Further analysis indicated that RAM performance was influenced by specific estrous cycle day, particularly during proestrus. Following 21 days of restraint stress all animals in proestrus, regardless of treatment, showed impaired acquisition. After 28 days, stressed females in proestrus performed better than proestrus controls. These results are discussed in relation to previously reported effects of stress in male rats. PMID:11406126

Bowman, R E; Zrull, M C; Luine, V N



Mitochondrial oxidative stress in female and male rat brain after ex vivo carbon monoxide treatment  

Microsoft Academic Search

Carbon monoxide (CO) is the most common cause of fatal poisoning all over the world. At the cellular level, a combination of tissue hypoxia and direct cellular damage underlie the pathophysiology of CO toxicity. The purpose of this study was to determine the effect of CO treatment on oxidative stress parameters in mitochondria isolated from male and female rat brains.

D. Taskiran; T. Nesil; K. Alkan



Effect of early nutritional experience on the feeding behaviour of adult female rats  

Microsoft Academic Search

In the present paper the effect of postnatal undernutrition on feeding behaviour has been evaluated in mature female Wistar rats subjected to food restriction a) during the suckling period, i. e. up to day 15 (SR), b) during the weaning period from day 15 to 30 (WR), c) throughout 30 days post partum (SWR) and d) during adulthood, i. e.




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...


Environmental enrichment promotes robust functional and histological benefits in female rats after controlled cortical impact injury.  


Environmental enrichment (EE) consistently induces marked benefits in male rats after traumatic brain injury (TBI), but whether similar efficacy extends to females is not well established. Hence, the aim of this study was to reassess the effect of EE on functional and histological outcome in female rats after brain trauma. Twenty-four normal cycling adult female rats underwent verification of estrous stage prior to controlled cortical impact (CCI) or sham injury and then were assigned to EE or standard (STD) housing. Motor function was assessed with beam-balance/beam-walk and rotarod tasks on post-operative days 1-5 and every other day from 1-19, respectively. Spatial learning/memory was evaluated in a Morris water maze on days 14-19. Morphologically intact hippocampal CA1/3 cells and cortical lesion volume were quantified 3weeks after injury. No differences were observed between the EE and STD sham groups in any endpoint measure and thus the data were pooled. In the TBI groups, EE improved beam-balance, beam-walk, rotarod, and spatial learning performance vs. STD (p's<0.05). EE also provided significant histological protection as confirmed by increased CA1/3 cell survival and decreased cortical lesion size vs. STD. These data demonstrate that EE confers robust benefits in female rats after CCI injury, which parallels numerous studies in males and lends further credence for EE as a preclinical model of neurorehabilitation. PMID:23333563

Monaco, Christina M; Mattiola, Vincent V; Folweiler, Kaitlin A; Tay, Justin K; Yelleswarapu, Narayana K; Curatolo, Lauren M; Matter, Ashley M; Cheng, Jeffrey P; Kline, Anthony E




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...


Monosodium Glutamate Disruption of Behavioral and Endocrine Function in the Female Rat  

Microsoft Academic Search

Experiments weie conducted to determine the effects of neonatal administration of L-monosodium glutamate (MSG) on behavioral and endocrine function in the female rat. Administration of MSG (4 mg\\/kg body weight) at days 1, 3, 5, 7 and 9 in neonates results in a delay of vaginal opening (VO) and the absence of ovulation at the time of VO. However, some

Jorge F. Rodriguez-Sierra; R. Sridaran; Charles A. Blake



Effects of Altered Food Intake during Pubertal Development in Male and Female Wistar Rats  

Microsoft Academic Search

The U.S. Environmental Protection Agency 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 nonspecific reduction in body weight (BWT) during the expo- sure period may

Susan C. Laws; Tammy E. Stoker; Janet M. Ferrell; Michelle G. Hotchkiss; Ralph L. Cooper



Reproductive evaluation of two pesticides combined (deltamethrin and endosulfan) in female rats  

Microsoft Academic Search

Data from in vitro studies suggest that the pesticides deltamethrin (D) and endosulfan (E) exert estrogen-like effects. There is concern that interaction between weakly estrogenic compounds can increase their estrogenic potency. The aim of the present study was to determine estrogenic activity in an animal model and the possible female reproductive adverse effects of these pesticides combined. Wistar rats received

Kenia M. Presibella; Diogo H. Kita; Claudia B. Carneiro; Anderson J. M. Andrade; Paulo R. Dalsenter



Green Tea Polyphenols and Vitamin D3 Protect Bone Microarchitecture in Female Rats with Chronic Inflammation  

Technology Transfer Automated Retrieval System (TEKTRAN)

Our recent study showed that green tea polyphenols (GTP) in conjunction with 1-a-OH¬vit-D3 (vitD3) treatment mitigates lipopolysaccharide (LPS)-induced bone mineral density loss in female rats. This study was undertaken to further explore the mechanism and bone microarchitecture of GTP plus vitD3 in...


Serotonin Transporter Deficiency Increases Abdominal Fat in Female, but Not Male Rats  

Microsoft Academic Search

Depression and abdominal obesity often co-occur, predominantly in women, and are associated with an increased risk for the development of glucose intolerance and subsequently type 2 diabetes. The underlying mechanisms are poorly understood. We found that female, but not male, depression-prone serotonin transporter knockout (SERT?\\/?) rats had a strong increase (54%) in abdominal fat, whereas no increases in plasma concentrations

Judith R. Homberg; Susanne E. la Fleur; Edwin Cuppen




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...


Acute Oral Toxicity of DMSO (Dimethyl Sulfoxide) Process Stream Samples in Male and Female Rats.  

National Technical Information Service (NTIS)

The acute toxicities of a single oral dose of the DMSO process stream samples, DMSO Evaporator Sludge, DMSO Recycle Solvent, and Virgin DMSO, were determined in male and female albino Sprague-Dawley rats. The DMSO Evaporator Sludge and Virgin DMSO solutio...

C. W. White J. Rodriguez G. E. Marrs



Time responses of cancellous and cortical bones to sciatic neurectomy in growing female rats  

Microsoft Academic Search

Effects of unilateral sciatic neurectomy on the responses of both cancellous and cortical bones were studied in growing female rats at 0, 1, 4, 8, and 12 weeks after operation. Using double-fluorescent labeling techniques, histomorphometric analyses were performed on longitudinal sections of proximal tibial metaphyseal secondary spongiosa (PTM) and on cross sections of tibial shaft (TX). In PTM, sciatic neurectomy

Q. Q. Zeng; W. S. S. Jee; A. E. Bigornia; J. G. KING; S. M. D'Souza; X. J. Li; Y. F. Ma; W. J. Wechter



Effects of Cadmium, Calcium, Age and Parity on Bone Mineral, Density and Strength in Female Rats.  

National Technical Information Service (NTIS)

Weanling female rats were fed diets containing one of three levels of calcium and one of four levels of cadmium in the drinking water. Approximately 10 animals from each group were sacrificed after the first pregnancy and the remaining animals after the f...

B. F. Hammond



Hypothermia and delayed fever in the male and female rat exposed to chlorpyrifos  

Microsoft Academic Search

Chlorpyrifos (CHL) is a commonly used organophosphate (OP) pesticide which irreversibly inhibits acetylcholinesterase activity in the CNS. Little is known regarding the thermoregulatory effects of CHL when administered orally and whether the sensitivity to CHL is affected by sex. To address these issues, male and female rats of the Long-Evans strain were administered 0, 10, 50, or 80 mg\\/kg CHL

Christopher J. Gordon; Tholeathcus A. Grantham; Ying Yang



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...


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...


Heightened cocaine-induced locomotor activity in adolescent compared to adult female rats  

PubMed Central

Initiation and experimentation with illicit drugs often occurs in adolescence. Evidence suggests that adolescent rats are more sensitive to some of the effects of drugs of abuse than adult rats. The present study investigated whether adolescent and adult female Sprague Dawley rats differ in cocaine-induced locomotor activity. Animals were placed in the test environment for 30 minutes, and then administered an intraperitoneal (IP) injection of either cocaine (20 mg/kg) or saline (0.9%). Both adult and adolescent animals showed significant increases in locomotor activity as a result of cocaine administration compared to saline controls. Interestingly, cocaine induced significantly more locomotor activity in the adolescent females compared to the adults, demonstrating that cocaine acts differently in developing animals.

Catlow, Briony J.; Kirstein, Cheryl L.



Environmental enrichment lowers stress-responsive hormones in singly housed male and female rats.  


Structural and social aspects of an environmental system can influence the physiology and behavior of animals occupying that system. This study examined the physiological effects of environmental enrichment (EE) with Kong Toys and Nestlets on stress-responsive hormones of the hypothalamic-pituitary-adrenal (HPA) axis under basal and mild stress conditions in singly housed, jugular vein-cannulated, male and female rats. Animals of both sexes housed with EE had significantly lower baseline adrenocorticotropic hormone (ACTH) and corticosterone (CORT) concentrations compared to those housed without EE. ACTH responses to the mild stress of saline injection were significantly lower in female rats housed with EE. Interaction with the Kong Toys and Nestlets appears to have provided the rats with a diversion from monotonous cage life, resulting in lower HPA axis activity before and after mild stress. These results are important because low, stable baselines are essential for accurately discerning pharmacological and other influences on the HPA axis. PMID:14643847

Belz, Emily E; Kennell, Jamilyn S; Czambel, R Kenneth; Rubin, Robert T; Rhodes, Michael E



Antifertility effect of Melia azedarach Linn. (dharek) seed extract in female albino rats.  


In the present study, the effect of oral administration of Melia azedarach Linn. (dharek) seed extract on fertility index, uterine weight and various histological and biochemical parameters of uterus were studied in the adult cyclic Wistar rats. Average number of embryos and implantation losses in the pregnant animals treated with dharek seed extract was also studied. The extract was prepared using a flash evaporator at 35 degrees C and dissolved in olive oil to prepare doses on per kg body weight basis. The results indicated a reduction in fertility index and average number of embryos in mated rats treated with the dharek extract. Pre-implantation, post-implantation and total prenatal mortalities were increased in rats treated with dharek seed extract during early (D1-D7) and late (D7-D18) stages of gestation period at doses of 5, 10 and 20 mg kg(-1) body wt day(-1). Histological studies showed a significant reduction in myometrial thickness, uterine gland diameter, luminal diameter of uterine glands and luminal epithelial cell height in rats treated with dharek seed extract at 1mg kg(-1) body wt day(-1) for 18 days. Pits and folds in luminal epithelial, mitotic activity in luminal and glandular epithelial cells of uterus were observed to be absent. Biochemically, a significant increase in protein and glycogen contents was observed. Thus, in conclusion, the application of this plant extract in rodent control programme may help to elevate the socioeconomic status of the society. PMID:17948733

Mandal, Reshu; Dhaliwal, Patwant Kaur



Proteomic analysis of amniotic fluid of pregnant rats with spina bifida aperta.  


Congenital spina bifida aperta is a common congenital malformation in children and has an incidence of 1‰ to 5‰ in China. However, we currently lack specific biomarkers for screening or prenatal diagnosis and there is no method to entirely cure or prevent such defects. In this study, we used two-dimensional gel electrophoresis (2-DE)/mass spectrometry (MS) to characterize differentially expressed proteins in amniotic-fluid samples (AFSs) of embryonic day (E) 17.5 rat fetuses with spina bifida aperta induced by retinoic acid (RA). We identified five proteins differentially expressed in AFSs of spina bifida aperta, including three upregulated proteins (transferrin, alpha-1 antiproteinase and signal recognition particle receptor, B subunit [SRPRB] 55 kDa), two downregulated proteins (apolipoprotein A IV [APO A4] and Srprb 77 kDa). Specifically, we found 11 alpha-1 fetoprotein (AFP) fragments that were downregulated and 35 AFP fragments that were upregulated in AFSs from embryos with spina bifida aperta. Of the downregulated AFP fragments, 72.7% (8/11) were confined to the AFP N-terminus (amino acids [aas] 25-440) and 77.1% (27/35) of upregulated AFP fragments were confined to the AFP C-terminus (aas 340-596). We also confirmed APO A4 and AFP by immunoblot analysis. This is the first comparative proteomic study of AFSs from rat fetuses with spina bifida aperta. We demonstrate proteomic alterations in the AFS of spina bifida aperta, which may provide new insights in neural tube defects and contribute to the prenatal screening. PMID:22108047

Shan, Liping; Fan, Yang; Li, Hui; Liu, Wei; Gu, Hui; Zhou, Fenghua; Yuan, Zhengwei



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



Effects of Maternal Behavior Induction and Pup Exposure on Neurogenesis in Adult, Virgin Female Rats  

PubMed Central

The states of pregnancy and lactation bring about a range of physiological and behavioral changes in the adult mammal that prepare the mother to care for her young. Cell proliferation increases in the subventricular zone (SVZ) of the female rodent brain during both pregnancy and lactation when compared to that in cycling, diestrous females. In the present study, the effects of maternal behavior induction and pup exposure on neurogenesis in nulliparous rats were examined in order to determine whether maternal behavior itself, independent of pregnancy and lactation, might affect neurogenesis. Adult, nulliparous, Sprague-Dawley, female rats were exposed daily to foster young in order to induce maternal behavior. Following the induction of maternal behavior each maternal subject plus females that were exposed to pups for a comparable number of test days, but did not display maternal behavior, and subjects that had received no pup exposure were injected with bromodeoxyuridine (BrdU, 90 mg/kg, i.v.). Brain sections were double-labeled for BrdU and the neural marker, NeuN, to examine the proliferating cell population. Increases in the number of double-labeled cells were found in the maternal virgin brain when compared with the number of double-labeled cells present in non-maternal, pup-exposed nulliparous rats and in females not exposed to young. No changes were evident in the dentate gyrus of the hippocampus as a function of maternal behavior. These data indicate that in nulliparous female rats maternal behavior itself is associated with the stimulation of neurogenesis in the SVZ.

Furuta, Miyako; Bridges, Robert S.



Binge eating proneness emerges during puberty in female rats: a longitudinal study.  


Puberty is a critical risk period for binge eating and eating disorders characterized by binge eating. Previous research focused almost entirely on psychosocial risk factors during puberty to the relative exclusion of biological influences. The current study addressed this gap by examining the emergence of binge eating during puberty in a rat model. We predicted that there would be minimal differences in binge eating proneness during pre-early puberty, but significant differences would emerge during puberty. Two independent samples of female Sprague-Dawley rats (n = 30 and n = 36) were followed longitudinally across pre-early puberty, mid-late puberty, and adulthood. Binge eating proneness was defined using the binge eating resistant (BER)/binge eating prone (BEP) model of binge eating that identifies BER and BEP rats in adulthood. Across two samples of rats, binge eating proneness emerged during puberty. Mixed linear models showed little difference in palatable food intake between BER and BEP rats during pre-early puberty, but significant group differences emerged during mid-late puberty and adulthood. Group differences could not be accounted for by changes in nonpalatable food intake or body weight. Similar to patterns in humans, individual differences in binge eating emerge during puberty in female rats. These findings provide strong confirming evidence for the importance of biological risk factors in developmental trajectories of binge eating risk across adolescence. PMID:21574664

Klump, Kelly L; Suisman, Jessica L; Culbert, Kristen M; Kashy, Deborah A; Sisk, Cheryl L



Autonomic activation associated with ethanol self-administration in adult female P rats  

PubMed Central

The present study examined changes in heart rate (HR) prior to and during limited access ethanol drinking in adult female P rats. P rats were implanted with radiotelemetric transmitters to measure HR. Daily testing involved a 90-min pre-test period (water only available) and a subsequent 90-min test period [either water (W) or ethanol available]. After a week of habituation, one ethanol group had access to ethanol for 7 weeks (CE), and another ethanol group had access for 4 weeks, was deprived for 2 weeks and then had access for a final week (DEP). Analyses of HR revealed that CE and DEP rats had significantly higher HR than W rats during test periods that ethanol was present and that DEP rats displayed higher HR during the early test period of the ethanol deprivation interval, as well. These data indicate that ethanol drinking induces HR activation in adult female P rats, and that this activation can be conditioned to the test cage environment, paralleling reports on contextual conditioning and cue-reactivity in alcoholics exposed to alcohol-associated stimuli. Therefore, this behavioral test may prove advantageous in screening pharmacotherapies for reducing craving and relapse, which are associated with cue-reactivity in abstinent alcoholics.

Bell, Richard L.; Rodd, Zachary A.; Toalston, Jamie E.; McKinzie, David L.; Lumeng, Lawrence; Li, Ting-Kai; McBride, William J.; Murphy, James M.



Diverse physiological consequences of long-term sucrose consumption in female rats.  


Although a considerable amount of work has addressed the short-term consequences of sucrose ingestion on a variety of morphological, physiological and hematological measures, relatively few studies have investigated these parameters following long-term sucrose intake. Results of the present experiments indicated that female rats given ad libitum access to a 10% sucrose solution for 9 months were conspicuously larger and had significantly heavier thyroid and spleen weights compared to rats offered either a restricted (20 min) daily sucrose option or control rats given only water. Rats given free access to sucrose also displayed abnormal serum levels of creatinine, sodium, phosphorus, alkaline phosphatase, alanine aminotransferase, uric acid and cholesterol which could indicate dysfunction in many organs including the kidney and liver. In the brain, however, chronic sucrose access was not associated with any discernable changes in neuronal or glial cell density within selected brain regions, but brain weight was found to be highly negatively correlated (r = - 0.97) with total sucrose intake. Finally, we report that high doses of estradiol can significantly attenuate the intake of sucrose in female rats. Together these findings demonstrate that free access to a sucrose solution for long periods can induce profound effects on rat physiology and may have important implications for the management of diet in humans. PMID:17539484

Galic, M A; Persinger, M A


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.

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



Tropisetron, a 5-HT(3) receptor antagonist, enhances object exploration in intact female rats.  


The effects of a 5-HT(3) receptor antagonist, tropisetron, on cognitive functions were evaluated using the object-recognition test in estrous (postovulatory) and in diestrous female rats. Recognition was measured by the ability of rats to discriminate between a familiar and a new object in a T-maze after a 3-h delay. Rats from both stages spent equivalent amounts of time exploring the objects on trial 1. Three hours after trial 1, trial 2 (test trial) was initiated. Before the test trial, rats were injected with either saline or 1.5 or 2.5 mg/kg tropisetron. During the test trial, one arm of a T-maze contained an object from trial 1 (familiar) and a new object (novel) was introduced into the other arm. Rats from both stages responded to tropisetron by showing a greater percentage of time exploring the novel object. These findings indicate that tropisetron facilitates cognition in female rats by improving the recognition of familiar information. PMID:23075706

Sawyer, John; Eaves, Emily L; Heyser, Charles J; Maswood, Sharmin



Binge Eating Proneness Emerges during Puberty in Female Rats: A Longitudinal Study  

PubMed Central

Puberty is a critical risk period for binge eating and eating disorders characterized by binge eating. Previous research focused almost entirely on psychosocial risk factors during puberty to the relative exclusion of biological influences. The current study addressed this gap by examining the emergence of binge eating during puberty in a rat model. We predicted that there would be minimal differences in binge eating proneness during pre-early puberty, but significant differences would emerge during puberty. Two independent samples of female Sprague-Dawley rats (n = 30 and n = 36) were followed longitudinally across pre-early puberty, mid-late puberty, and adulthood. Binge eating proneness was defined using the binge eating resistant (BER)/binge eating prone (BEP) model of binge eating that identifies BER and BEP rats in adulthood. Across two samples of rats, binge eating proneness emerged during puberty. Mixed linear models showed little difference in palatable food intake between BER and BEP rats during pre-early puberty, but significant group differences emerged during mid-late puberty and adulthood. Group differences could not be accounted for by changes in non-palatable food intake or body weight. Similar to patterns in humans, individual differences in binge eating emerge during puberty in female rats. Findings provide strong confirming evidence for the importance of biological risk factors in developmental trajectories of binge eating risk across adolescence.

Klump, Kelly L.; Suisman, Jessica L.; Culbert, Kristen M.; Kashy, Deborah A.; Sisk, Cheryl L.



Effects of growth hormone on bone modeling and remodeling in hypophysectomized young female rats: a bone histomorphometric study  

Microsoft Academic Search

Growth hormone (GH) deficiency causes decreased bone mineral density and osteoporosis, predisposing to fractures. We investigated\\u000a the mechanism of action of GH on bone modeling and remodeling in hypophysectomized (HX) female rats. Thirty female Sprague–Dawley\\u000a rats at age 2 months were divided into three groups with 10 rats each: control (CON) group, HX group, and HX + GH (3 mg\\/kg\\u000a daily SC) group, for

Lysette IglesiasJames; James K. Yeh; Mariano Castro-Magana; John F. Aloia



The Effects of Ovariectomy on Binge Eating Proneness in Adult Female Rats  

PubMed Central

Ovarian hormones are associated with binge eating in women, however findings are limited by the lack of experimental control inherent in human studies. Animal research that manipulates ovarian hormone status and examines individual differences in extreme binge eating proneness are needed to model clinical phenotypes in humans and to confirm causal effects. The purpose of this study was to examine the effects of adult ovariectomy on overall binge eating risk and extreme binge eating phenotypes using the binge eating resistant (BER)/ binge eating prone (BEP) rat model. We predicted that palatable food consumption would significantly increase after ovariectomy in all rats because ovarian hormones generally suppress food intake. If differences in responsiveness to ovarian hormones underlie BER/BEP phenotypes, then differences in binge eating between BER and BEP rats would be eliminated or diminished after ovariectomy. Changes in palatable food (PF) intake were compared in BER and BEP rats before and after ovariectomy in two samples of adult females. Findings were highly similar in the two samples. PF intake increased significantly following ovariectomy in all rats. However, BEP rats consistently consumed larger amounts of PF than BER rats, both before and after ovariectomy. The consistency of findings across two samples of rats provides strong support for activational effects of ovarian hormones on binge eating. However, the immunity of extreme binge eating phenotypes to ovarian hormone ablation suggests that other, earlier mechanisms (e.g., organizational hormone effects or hormone-independent effects) determine the expression of binge eating phenotypes.

Klump, Kelly L.; Suisman, Jessica L.; Culbert, Kristen M.; Kashy, Deborah A.; Keel, Pamela K.; Sisk, Cheryl L.



Effects of dehydration and salt-loading on hypothalamic vasopressin mRNA level in male and female rats  

Microsoft Academic Search

Experiments were carried out on 9- to 11-week-old male and female Sprague-Dawley rats. Dot-blot analysis and 3?-end digoxigenin-labeled 26mer oligonucleotide probe were used in the investigation of vasopressin (AVP) mRNA level in the hypothalamus of male and female rats. The normal hypothalamic AVP-mRNA level in males was 48% higher than that in females (P < 0.05). Plasma osmolality was also

Wen-Jie Dai; Tai Yao



Caffeine inhibits development of benign mammary gland tumors in carcinogen-treated female Sprague-Dawley rats  

Microsoft Academic Search

Summary The purpose of this study was to assess the influence of caffeine on the incidence of benign mammary tumors in carcinogen (DMBA) treated female Sprague-Dawley rats. Four different animal models were used in these studies, i.e., the administration of DMBA to: [1] 55 day old virgin rats; [2] 53 day old ovariectomized, estrogen treated virgin rats; [3] 135 day

David M. Wolfrom; A. Ramesha Rao; Clifford W. Welsch



Natriuretic peptide system: A link between fat mass and cardiac hypertrophy and hypertension in fat-fed female rats  

Microsoft Academic Search

The present study was designed to develop an animal model of hypertension and cardiac hypertrophy associated with obesity in female rats. Furthermore, we studied the involvement of the natriuretic peptide system in the mechanisms of these conditions. Obesity was induced in Wistar rats by a high fat diet and ovariectomy. The rats were divided into four groups: ovariectomized or sham-operated

Everaldo Nery de Andrade; Gleisy Kelly Neves Gonçalves; Thiago Henrique Caldeira de Oliveira; Caroline Silva dos Santos; Clarissa Leal Silva e Souza; Luciana Barbosa Firmes; Amélia Cristina Mendes de Magalhães; Telma de Jesus Soares; Adelina Martha dos Reis; Najara de Oliveira Belo



In utero phthalate effects in the female rat: A model for MRKH syndrome.  


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 phenomenon that is better studied in male offspring than females. The current study reports female reproductive tract malformations in the Sprague-Dawley rat similar to those characteristic of MRKH syndrome, following in utero exposure to a mixture of 5 PEs. We determined that females are ~2-fold less sensitive to the effects of the 5-PE mixture than males for reproductive tract malformations. We were not fully successful in defining the critical exposure period for females; however, incidence of malformations was 88% following dosing from GD8 to 19 versus 22% and 0% for GD8-13 and GD14-19, respectively. Overall, this study provides valuable information regarding female vulnerability to in utero phthalate exposure and further characterizes a potential model for the human MRKH syndrome. PMID:23542816

Hannas, Bethany R; Howdeshell, Kembra L; Furr, Johnathan; Earl Gray, L



Synergism of estrogens and x-rays in mammary carcinogenesis in female ACI rat  

SciTech Connect

A previously demonstrated synergistic interaction between diethylstilbestrol (DES) and radiation on rate mammary carcinogenesis was extended to another estrogen, 17-ethinyl-estradiol (EE2). These newly reported results with EE2 demonstrated that the previously reported synergistic interaction between DES and radiation is not confined to just DES. Instead, these new results implied that the synergistic interaction is a synergistic interaction between the estrogenic activity of DES and radiation on rat mammary carcinogenesis. Female inbred ACI rats were used. By the end of the experiment, no neoplasia was detected in rats bearing cholesterol pellets, with an without x-ray exposure. No significant n tumor data were obtained from rats treated with 0.1 mg EE2, with and without x-rays. Approximately 50% of the rats treated with DES and approximately 90% of the rats treated with 1 mg EE2 had 1 or more mammary adenocarcinomas (MAC). X-rays synergistically increased the number of MAC per rat in the groups implanted with DES or 1 mg EE2. X-rays also increased the trend toward earlier increased incidence of rats with MAC as compared to rats treated with estrogens only. All rats treated with DES and 1 mg EE2 had pituitary tumors. The mean weight of the pituitary tumors in the groups treated with 1 mg EE2 was approximately 1.5 times that of the groups treated with DES. Mean terminal plasma prolactin levels for rats treated with 1 mg EE2 or DES were, respectively, 17.5 and 9.5 times control values.

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



Immune response modulation in acutely ethanol-intoxicated, acutely diabetic male and female rats.  


We examined how acute diabetes mellitus and acute ethanol intoxication modulate factors that mediate immune responses as a basis for explaining the increased susceptibility to infection in these two conditions. Our working hypothesis is that ethanol intoxication in diabetes compromises host defense mechanisms to a greater extent than observed in each condition alone. Male and female rats were made diabetic with streptozotocin (65 mg/kg, i.p.). Forty-eight hours after administration of streptozotocin, rats either received no treatment (control group) or were treated with (1) ethanol (bolus injection of 1.75 g/kg, followed by a 3-h infusion at the rate of 300 mg/kg/h), (2) lipopolysaccharide [(LPS); 0.9 mg/kg], or (3) a combination of LPS+ethanol. At the end of 3 h, rats were killed, and the livers were digested by perfusion with collagenase-containing Hanks' balanced salt solution to isolate hepatocytes and Kupffer cells. To measure chemokine generation, hepatocytes (2.5x10(5) cells per well) and Kupffer cells (1x10(6) cells per well) were cultured for 20 h, and the supernatant was used to measure cytokine-induced neutrophil chemoattractant (CINC) and regulated on activation, normal T-cell expressed and secreted (RANTES) chemokines. Phagocytosis by Kupffer cells was measured by flow cytometry and expressed as mean channel fluorescence intensity (MCF). Induction of diabetes as well as treatment of nondiabetic rats with LPS, ethanol, or LPS+ethanol caused depression of MCF values of Kupffer cells. However, treatment of the diabetic male and female rats with LPS and LPS+ethanol increased the MCF values relative to those of Kupffer cells obtained from untreated diabetic rats, but administration of ethanol to diabetic rats did not have a similar effect. The induction of diabetes caused an increase in CINC generation by Kupffer cells obtained from male rats, but not from female rats. This diabetes-induced elevation of chemoattractant factor was decreased when diabetic animals were treated with LPS, ethanol, or LPS+ethanol, and the sex difference was obliterated. Thus, the induction of diabetes as well as treatment with LPS, ethanol, or LPS+ethanol in nondiabetic rats depressed the phagocytic capability of Kupffer cells, whereas the presence of endotoxemia (administration of the endotoxin LPS) or administration of LPS+ethanol reversed the diabetic effect, but ethanol intoxication did not. These findings seem to indicate a persistence of depression of host defense capacity in the ethanol-intoxicated diabetic condition. This is further reinforced by the depression of the diabetes-induced enhancement of chemotaxis when the diabetic rats became intoxicated. PMID:14693262

Olubadewo, Joseph O; Spitzer, Judy A



Characterization of maternal transfer of decabromodiphenyl ether (BDE-209) administered to pregnant Sprague-Dawley rats.  


To evaluate maternal transfer of decabromodiphenyl ether (BDE-209), Sprague-Dawley rats were given daily oral doses of 5 ?mol/kgb.w. BDE-209 in peanut oil from gestation day (GD) 7 to postpartum day (PD) 4. BDE-209 was increased temporally in maternal blood, placenta, fetuses and neonates. Furthermore, more BDE-209 was found in neonate whole-body samples obtained during lactational period (PD 4) than in that of fetal whole-body samples during pregnancy GD 15 and 21. Overall an increase was observed over time for nona-BDE levels in maternal blood and placenta, but these congeners were decreased in fetuses or neonates. Slight changes were observed for octa-BDEs in both maternal blood and placenta while a significant decrease was observed in the fetuses or neonates for BDE-196 and 198/203. These results demonstrated that BDE-209 and its metabolites can transport to the placenta and milk, and eventually enter the fetuses and/or the neonates. PMID:20851178

Cai, Yunmei; Zhang, Wenbing; Hu, Junjie; Sheng, Guoying; Chen, Dunjin; Fu, Jiamo



Hypercholesterolemia and 3-hydroxy-3-methylglutaryl coenzyme A reductase regulation in aged female rats.  


Coronary heart disease is less prevalent in pre-menopausal women than in men, but increases at the onset of menopause. This delay is due to estrogen protective effects. The rise of cholesterolemia is one of the main risk factors for coronary disease. Since 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) is the rate-limiting enzyme of the cholesterol biosynthetic pathway, it plays a pivotal role in cholesterol homeostasis maintenance. Aim of this study is to investigate whether HMGR is involved in the cholesterolemia increase that occurs during aging, and to consider its potential role as a target for estrogen protective effects. "In vivo" studies have been performed using the livers of 12-month-old female rats (whose estrogen level decrease is comparable to the one detected at the occurrence of human menopause), 12-month-old female rats treated with 17-beta-estradiol, and 3-month-old untreated male and female rats. The results indicated hypercholesterolemic status and a significant increase of HMGR activity according to a reduced activation of AMPK detected in treated rats compared to controls. Furthermore, 17-beta estradiol treatment reduced HMGR activity restoring AMPK activation. These findings highlight the correlation between estrogen and HMGR short-term regulation, and suggest the presence of another mechanism underlying the protective role of estrogen in age-related diseases. PMID:19895880

Trapani, Laura; Violo, Francesca; Pallottini, Valentina



Intrauterine growth restriction decreases endochondral ossification and bone strength in female rats.  


Intrauterine growth restriction (IUGR) modifications to postnatal skeletal growth may increase adult fracture, especially in females who have greater risk of osteoporosis. Little is known about the effect of IUGR on the patterns of postnatal endochondral ossification and bone development. Here for the first time we reveal bone formation, mineralization, and strength in IUGR female rats during early postnatal life and adulthood. Endochondral ossification rate of the hypertrophic zone (HZ) and hypertrophic cell length (HCL) at distal femur and proximal tibia, and primary ossification center (POC) of the whole femur and tibia were quantified at birth to day 21. Bone area (BA), bone mineral content (BMC), and bone density by dual-energy X-ray absorptiometry and bone strength determined from three-point bending were measured at days 21 and 120. IUGR femur and tibia HZ, HCL, and POC were significantly diminished at birth to day 21. IUGR decreased BA and BMC as well as femur/tibia diameter, length, stiffness, and peak load values at days 21 and 120. Our findings demonstrate a negative long-term effect of IUGR on bone size, mineral content, and strength in weanling and adult female rats. We speculate that IUGR decreases endochondral ossification responsiveness, and in turn, postnatal linear skeletal growth, mineralization, and strength in female rats. PMID:22875655

Chen, Haiyan; Miller, Scott; Lane, Robert H; Moyer-Mileur, Laurie J



Effects of acute ethanol administration of female rat liver as a function of aging  

SciTech Connect

Female Fischer 344 rats, aged 4, 14, and 25 months, received 4.0 g/kg of ethanol by intraperitoneal (i.p.) injection. Blood alcohol concentrations 2.5, 6 and 16 hr after ethanol injection were similar in the three age groups. Hepatic glutathione (GSH) levels were diminished 6 hr after ethanol injection, and there were no age-dependent differences in the depleted levels (3.2 {plus minus} 0.1, 3.5 {plus minus} 0.2, and 3.0 {plus minus} 0.5 {mu}g GSH/g liver). However, GSH contents in livers of young-adult rats approached control levels after 16 hr, whereas they remained depressed in older rats. Serum levels of hepatic enzymes were significantly elevated 6 hr after ethanol administration. The increases were greater in middle-aged and old rats than in young-adult rats. The results suggest that middle-aged and old rats are more susceptible than young rats to the acute toxicity of ethanol.

Rikans, L.E.; Snowden, C.D. (Univ. of Oklahoma College of Medicine, Oklahoma City (USA))



Early impact of a fat-enriched diet on behavioral responses of male and female rats.  


Prolonged high-fat diets have been shown to affect an organism's stress responsiveness at the neuroendocrine level. In the present study, the authors used a 7-day protocol of fat administration in adult rats of both sexes to investigate the early behavioral impact of a moderately fat (20%) diet, often used by Western societies, on rats' reaction to acute stress and novelty. Their results show that this diet can reduce the rats' active behavioral responses to subsequent stressors and influence their corticosterone secretion. Fat-fed male rats adopted a less active behavior to cope with forced swimming stress, whereas their exploratory behavior in the open field environment was rather increased compared with chow-fed males. Fat-fed female rats exhibited a less active behavioral response to both stress paradigms compared with their chow-fed counterparts. Fat diet abolished facilitation in corticosterone secretion following a subsequent stressor in both sexes. However, only in males did fat diet exaggerate corticosterone response to novelty, irrespective of the previous stress history of the rat. These data indicate that a short-term metabolic stress can modify the rats' stress coping strategy in interaction with the gender. PMID:17592939

Soulis, G; Papalexi, E; Kittas, C; Kitraki, E



Age-related changes in dorsal root ganglia, circulating and vascular calcitonin gene-related peptide (CGRP) concentrations in female rats: Effect of female sex steroid hormones  

PubMed Central

The aim of the present study is to investigate whether immunoreactive (I) calcitonin gene-related peptide (CGRP) content is decreased in plasma and mesenteric arteries (resistance arteries) in middle-aged rats and if so, whether sex steroid hormones enhance I-CGRP in middle-aged female rats. We also examined whether vascular CGRP receptor components, calcitonin receptor like receptor (CRLR) and receptor activity modifying protein 1 (RAMP1) are elevated by sex steroid hormones treatment in middle-aged female rats. Young adult (3 months old) and middle-aged (10–12 months old) ovariectomized rats were treated subcutaneously with estradiol-17? (E2; 2 mg), progesterone (P4; 5 mg), E2 +P4 (2 mg + 20 mg) or placebo (control). Radioimmunoassay and Western blot analysis were performed to measure I-CGRP content and CGRP receptor components in dorsal root ganglia (DRG), in resistance arteries and in plasma. Immunofluorescent staining methods were employed to determine cellular localization of CRLR, RAMP1 in resistance arteries. Our data demonstrated that I-CGRP content was significantly (p < 0.05) lower in the plasma and resistance arteries of middle-aged female rats compared to young controls. Both RAMP1 and CRLR were concentrated in vascular endothelium and the underlying smooth muscle cells. RAMP1 but not CRLR appeared to be decreased in middle-aged rat vasculature. Chronic perfusion of sex steroid hormones to ovariectomized rats: (1) significantly (p < 0.05) elevated I-CGRP in the DRG and in the plasma, and (2) significantly elevated RAMP1 (p < 0.05) but did not alter CRLR in resistance arteries. These data suggest that female sex steroid treatment enhances I-CGRP and its receptors, and thus regulate the blood pressure in aged female rats.

Gangula, Pandu R.R.; Chauhan, Madhu; Reed, Luckey; Yallampalli, Chandra



Serotonergic system involvement in the inhibitory action of estrogen on induced sodium appetite in female rats.  


This study of the participation of the serotonergic system in the inhibitory effect of estrogen on induced sodium appetite in female rats explores sodium appetite induced by Furosemide and low sodium diet treatment (DEP) in normally cycling rats and in ovariectomized rats with and without estradiol replacement (OVX, OVX+E(2)). We also analyzed the neural activity of serotonergic neurons of the dorsal raphe nucleus (DRN) as well as the activity of other brain nuclei previously found to be involved in sodium and water balance in sodium depleted animals without access to the intake test. For this purpose, we examined the brain Fos, Fos-serotonin and Fos-vasopressin immunoreactivity patterns in diestrus (D), estrus (E), OVX and OVX+E(2) rats subjected to DEP. Female rats in E and OVX+E(2) exhibited a significant decrease in induced sodium intake compared with females in D and OVX. This estrogen-dependent inhibition on induced sodium appetite (approximately 50% reduction) can be correlated with changes in Fos activation observed in the organum vasculosum of the lamina terminalis (OVLT) and DRN, in response to sodium depletion. Given our previous observations in males, the expected sodium depletion-induced activity of the OVLT was found to be absent in OVX+E(2) females, while the usual inhibitory tonic activity of serotonergic neurons of the DRN, instead of decreasing after sodium depletion, increases or remains unchanged in OVX+E(2)-DEP and E-DEP females, respectively. Regarding urinary water and sodium excretion 3h after furosemide treatment, E-DEP and OVX+E(2)-DEP animals excreted smaller volumes of more highly concentrated urine than depleted D and OVX rats. Twenty hours after sodium depletion, the same groups of animals also showed a significant increase in the number of Fos-AVP immunoreactive neurons within the supraoptic nucleus, compared with D-DEP. In summary, our results demonstrate an estrogen-dependent inhibition of induced sodium appetite in normally cycling rats and ovariectomized animals with estradiol replacement, which may involve an interaction between excitatory neurons of the OVLT and inhibitory serotonergic cells of the DRN. The main finding is thus serotonergic system involvement as a possible mechanism in the inhibitory action of estrogen on induced sodium appetite. PMID:21554894

Dalmasso, Carolina; Amigone, José Luis; Vivas, Laura



Nature of changes in adrenocortical function in chronic hyperleptinemic female rats.  


Neonatal treatment of rats with monosodium L-glutamate, which destroys hypothalamic arcuate nucleus neuronal bodies, induces several metabolic abnormalities; as a result, rats develop a phenotype of pseudoobesity. This study was designed to explore, in the monosodium L-glutamate-treated female rat, the influence of chronic hyperleptinemia on adrenal cortex functionality. For this purpose, we evaluated in control and hypothalamic-damaged rats: (a) in vivo and in vitro adrenocortical function, (b) adrenal leptin receptor immunodistribution and mRNA expression, and (c) whether the inhibitory effect of leptin on adrenal function remains. Our results indicate that, compared to normal counterparts, pseudoobese animals displayed (1) hyperadiposity, despite being hypophagic and of lower body weight, (2) in vivo and in vitro enhanced adrenocortical response to ACTH stimulation, (3) an in vitro adrenal fasciculata-reticularis cell hyper-sensitivity to ACTH stimulus, (4) hyperplasia of their adrenal zona fasciculata cells, and (5) adrenal fasciculata-reticularis cell refractoriness to the inhibitory effect of leptin on ACTH-stimulated glucocorticoid production due, at least in part, to decreased adrenal leptin receptor expression. These data further support that increased hypothalamo-pituitary-adrenal axis function, in the adult neurotoxin-lesioned female rat, is mainly dependent on the development of both hyperplasia of adrenal zona fasciculata and adrenal gland refractoriness to leptin inhibitory effect. Our study supports that adrenal leptin resistance could be responsible, at least in part, for enhanced glucocorticoid circulating levels in this phenotype of obesity. PMID:15347844

Perelló, Mario; Moreno, Griselda; Camihort, Gisela; Luna, Georgina; Cónsole, Gloria; Gaillard, Rolf C; Spinedi, Eduardo



Seizure susceptibility in intact and ovariectomized female rats treated with the convulsant pilocarpine  

PubMed Central

Despite numerous neuroendocrinological studies of seizures, the influence of estrogen and progesterone on seizures and epilepsy remains unclear. This may be due to the fact that previous studies have not systematically compared distinct endocrine conditions and included all relevant controls. The goal of the present study was to conduct such a study using pilocarpine as chemoconvulsant. Thus, age and weight-matched, intact or ovariectomized rats were tested to determine incidence of status epilepticus and to study events leading to status. Intact female rats were sampled at each cycle stage (proestrus, estrus, metestrus, or diestrus 2). Convulsant was administered at the same time of day, 10:00–10:30 a.m. Statistical analysis showed that there was a significantly lower incidence of status on the morning of estrus, but differences were attenuated in older animals. Ovariectomized rats were distinct in their rapid progression to status. These results show that the incidence of status in female rats following pilocarpine injection, and the progression to pilocarpine-induced status, are influenced by reproductive state as well as age. The hormonal milieu present specifically on the morning of estrus appears to decrease susceptibility to pilocarpine-induced status, particularly at young ages. In contrast, the chronic absence of reproductive steroids that characterizes the ovariectomized rat leads to a more rapid progression to status. This dissociation between incidence vs. progression provides new insight into the influence of estrogen and progesterone on seizures.

Scharfman, Helen E.; Goodman, Jeffrey H.; Rigoulot, Marie-Aude; Berger, Russell E.; Walling, Susan G.; Mercurio, Thomas C.; Stormes, Kerry; Maclusky, Neil J.



Neonatal ventral hippocampal lesions in male and female rats: Effects on water maze, locomotor activity, plus-maze and prefrontal cortical GABA and glutamate release in adulthood  

Microsoft Academic Search

Schizophrenia is characterized by diverse behavioural and neurochemical abnormalities that may be differentially expressed in males and females. Male rats with neonatal ventral hippocampal lesions (nVHL) have commonly demonstrated behavioural and neurochemical abnormalities similar to those in schizophrenia. Fewer studies have used female rats. We investigated the hypothesis that male and female nVHL rats will demonstrate behavioural abnormalities accompanied by

Richard J. Beninger; Katharine J. Tuerke; Jennifer K. Forsyth; Andrew Giles; Lihua Xue; Roland J. Boegman; Khem Jhamandas



Toxicological Approach in Chronic Exposure to Lead on Reproductive Functions in Female Rats (Rattus Norvegicus)  

PubMed Central

Lead being a toxic cumulative poison and an environmental pollutant, experiments were conducted at an oral chronic dose of (60 mg/kg/day) for 90 days on adult female rats (Rattus Norvegicus) and its effect on the reproductive functions in relation to the biochemical effects was studied. It was observed that the chronic dose of lead caused an elevation in the level of proteins, acid phosphatase, alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase in all the soft tissues studied indicating tissue damage. It also inhibited the level of acetylcholinesterase in all the tissues. Fertility tests by pairing treated females with males showed that lead-treated female showed irregular estrous cycle and the fertility rate dropped to 40% as female pups of lead-treated mothers showed loss in weight, high mortality rate, poor growth rate, and late vaginal opening. Histological studies of ovary showed atresia in all the stages of folliculogenesis sustaining the poor fertility observations. The present study revealed that lead caused great tissue damage and affected reproductive performance of female rats at a chronic dose.

Dhir, V.; Dhand, P.



Lack of Hydroxylated Fullerene Toxicity after Intravenous Administration to Female Sprague-Dawley Rats  

PubMed Central

Hydroxylated fullerenes (C60OHx) or fullerols are water-soluble carbon nanoparticles that have been explored for potential therapeutic applications. This study assessed acute in vivo tolerance in 8 week old female Sprague Dawley rats to intravenous administration (IV) of 10 mg/kg of well-characterized C60(OH)30. Complete histopathology and clinical chemistries were assessed at 8, 24, and 48 hr after dosing. Minor histopathology changes were seen, primarily in one animal. No clinically significant chemistry changes were observed after treatment. These experiments suggest that this fullerol was well tolerated after IV administration to rats.

Monteiro-Riviere, Nancy A.; Linder, Keith E.; Inman, Alfred O.; Saathoff, John G.; Xia, Xin-Rui; Riviere, Jim E.



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

Microsoft Academic Search

Objective  Green tea proposes anti-inflammatory properties which may attenuate chronic inflammation-induced fibrosis of vessels. This\\u000a study evaluated whether green tea polyphenols (GTP) can avert fibrosis or vascular disruption along with mechanisms in rats\\u000a with chronic inflammation.\\u000a \\u000a \\u000a \\u000a \\u000a Treatments  Forty 3-month-old female rats were assigned to a 2 (placebo vs. lipopolysaccharide, administration) × 2 (no GTP vs. 0.5% GTP\\u000a in drinking water) factorial design for 12 weeks.

Chwan-Li Shen; Christina Samathanam; Owatha L. Tatum; Suzanne Graham; Christine Tubb; Jay J. Cao; Dale M. Dunn; Jia-Sheng Wang



Effects of perinatal exposure to bisphenol A on sociosexual behavior of female and male rats.  

PubMed Central

Perinatal action of estrogens or aromatizable steroids at the central nervous system level is responsible for brain sexual differentiation. Through early contact with the central nervous system, the estrogenic compound bisphenol A (BPA) could alter the processes affecting sociosexual behavior. To test this hypothesis, we studied agonistic and sexual behavior of adult female and male rats whose mothers were administered BPA (40 microg/kg/day) during pregnancy or lactation. An intruder test revealed in males but not in females an increase in defensive behavior due to BPA. We studied the effect of BPA on sexual behavior by testing sexual orientation and sexual activity. Male sexual orientation toward a stimulus female was not affected by BPA, whereas the sexual activity test revealed a slight impairment of sexual performance due to BPA in terms of latency and frequency of intromissions. In females, BPA produced a small increase in sexual motivation and receptive behavior. In conclusion, BPA administration, both during pregnancy and during lactation, does not masculinize female behavior or potentiate masculinization processes of males. On the contrary, we observed a potentiation of female behavior in females and a depotentiation of male behavior in males.

Farabollini, Francesca; Porrini, Stefania; Della Seta, Daniele; Bianchi, Fiorella; Dessi-Fulgheri, Francesco



Differentiation in boron distribution in adult male and female rats' normal brain: a BNCT approach.  


Boron distribution in adult male and female rats' normal brain after boron carrier injection (0.005 g Boric Acid+0.005 g Borax+10 ml distilled water, pH: 7.4) was studied in this research. Coronal sections of control and trial animal tissue samples were irradiated with thermal neutrons. Using alpha autoradiography, significant differences in boron concentration were seen in forebrain, midbrain and hindbrain sections of male and female animal groups with the highest value, four hours after boron compound injection. PMID:22484141

Goodarzi, Samereh; Pazirandeh, Ali; Jameie, Seyed Behnamedin; Khojasteh, Nasrin Baghban



[Role of estradiol in hypoxia-induced pulmonary hypertension in female rats].  


Gender differences play role in pathogenesis and treatment of many cardiovascular diseases. One of these diseases is hypoxia-induced pulmonary hypertension (PHT). The aim of this study was to analyze the involvement of female hormone estradiol in development of hypoxia-induced PHT in female Wistar rats. PHT was induced by exposure to hypobaric hypoxia in an altitude chamber at a simulated altitude of 5000 m (02 concentration reduced to 10 %), 10 h per day for 2 weeks. The development of PHT leads to a twofold increase in the level of estradiol. Ovariectomy decreases by half the level of estradiol and causes significant decrease in hypoxia-induced PHT symptoms. PMID:23700662

Kovaleva, Iu O; Artem'eva, M M; Ilatovskaia, M E; Medvedev, O S; Medvedeva, N A



BOLD Signal Response to Cocaine Varies with Sexual Receptivity in Female Rats  

PubMed Central

Blood oxygen level dependent (BOLD) MRI was used to test whether cocaine-stimulated mesolimbic activity varied with sexual receptivity. Rats were randomly screened for lordotic responses and then imaged for their response to centrally administered cocaine. We observed that females expressing no lordosis showed a greater activation of mesolimbic and nigrostriatal structures than lordotic females. Our data suggest that the differential sensitivity to cocaine occurs not only as a result of hormonal changes of the estrous cycle, but also in association with changes in sexual receptivity.

Febo, Marcelo; Segarra, Annabell C.; Stolberg, Tara L.; Ferris, Craig F.



Unit: Males and Females, Inspection Pack, National Trial Print.  

ERIC Educational Resources Information Center

|This is a National Trial Print of an Australian Science Education Project unit entitled Males and Females. Materials provided consist of a teacher's edition of the written materials, a student record book, and seven large black and white photographs showing various stages in the dissection of a pregnant rat. This unit has been written to help…

Australian Science Education Project, Toorak, Victoria.


Estrogen and aging affect the synaptic distribution of estrogen receptor beta-immunoreactivity in the CA1 region of female rat hippocampus  

Microsoft Academic Search

Estradiol (E) mediates increased synaptogenesis in the hippocampal CA1 stratum radiatum (sr) and enhances memory in young and some aged female rats, depending on dose and age. Young female rats express more estrogen receptor ? (ER?) immunolabeling in CA1sr spine synapse complexes than aged rats and ER? regulation is E sensitive in young but not aged rats. The current study

Elizabeth M. Waters; Murat Yildirim; William G. M. Janssen; W. Y. Wendy Lou; Bruce S. McEwen; John H. Morrison; Teresa A. Milner



Early maternal separation increases symptoms of activity-based anorexia in male and female rats.  


Running activates the hypothalamic-pituitary-adrenal (HPA) axis, increasing the release of stress hormones known to exert anorexic effects. HPA axis reactivity is strongly influenced by early postnatal manipulations, including removal of pups from the dam for short (handling) or prolonged (maternal separation) durations during the preweaning period. The authors examined the effects of handling and maternal separation on food intake, body weight loss, and running rates of young adult male and female rats in the activity-based anorexia (ABA) paradigm. Postnatal treatment did not affect adaptation to a 1-hr restricted feeding schedule before the introduction of wheel running. During the ABA paradigm, maternally separated animals lost weight faster, ate less, ran more, and required fewer days to reach removal criterion compared with handled rats. Females were particularly vulnerable. These findings indicate that early postnatal treatment and sex influence ABA. PMID:19594284

Hancock, Stephanie; Grant, Virginia



Humoral (immunological) responses in female albino rats during rotating magnetic field exposures  

NASA Astrophysics Data System (ADS)

Experiments were designed to evaluate the primary and secondary humoral responses to a rotating magnetic field configuration, which is known to evoke significant biobehavioral changes. Ten days after inoculation with human serum albumin and 10 days before a booster, female rats were exposed to eigher a 0.5 Hz rotating magnetic field (RMF) or to room conditions (control). The lighting schedule was either continuous or involved a light-dark cycle (LD) of 12:12h. A third group of rats served as colony room controls. Group differences of low statistical significance were found when females were exposed to continuous lighting rather than the LD 12:12 light-dark cycle. However, the effects were considered trivial and not sufficient to explain the previously reported biobehavioral changes evoked by this field configuration.

Reid, K.; Falter, H.; Persinger, M. A.



Effects of ethanol or rimcazole on dizocilpine maleate–induced behaviors in male and female rats  

Microsoft Academic Search

The current investigation was undertaken to explore further the interactions between ethanol and the phencyclidine analog dizocilpine maleate (MK-801) on behaviors in male and female rats. It was previously found that ethanol dependence conferred cross-tolerance to the behaviorally activating effects of dizocilpine. The current set of studies was designed to assay the interactions between dizocilpine and ethanol in ethanol-naive animals

Leslie L Devaud



Profile of acetylcholinesterase in brain areas of male and female rats of adult and old age  

Microsoft Academic Search

Inhibition of acetylcholinesterase (AChE)-metabolizing enzyme of acetylcholine, is presently the most important therapeutic target for development of cognitive enhancers. However, AChE activity in brain has not been properly evaluated on the basis of age and sex. In the present study, AChE activity was investigated in different brain areas in male and female Sprague-Dawley rats of adult (3 months) and old

A. Das; M. Dikshit; C. Nath



Effects of Nicotine on Bone and Calciotropic Hormones in Growing Female Rats  

Microsoft Academic Search

.   Limited research in young adults and immature animals suggests a detrimental effect of tobacco on bone during growth. This\\u000a study investigated the effects of nicotine, the major alkaloid component of tobacco, on calciotropic hormone concentrations\\u000a and bone status in growing female rats. One-month-old animals received either saline (n = 10), nicotine at 3.0 mg\\/kg\\/day (n\\u000a = 10), or nicotine

U. T. Iwaniec; Y. K. Fung; D. M. Cullen; M. P. Akhter; M. C. Haven; M. Schmid



Brain hyperthermia and temperature fluctuations during sexual interaction in female rats  

Microsoft Academic Search

Since the metabolic activity of neural cells is accompanied by heat release, brain temperature monitoring provides insight into behavior-associated changes in neural activity. In the present study, local temperatures were continuously recorded in several brain structures (nucleus accumbens, medial–preoptic hypothalamus and hippocampus) and a non-locomotor head muscle (musculus temporalis) in a receptive female rat during sexually arousing stimulation and subsequent

Robert D. Mitchum; Eugene A. Kiyatkin



Relationship between utilization of fat and synthesis of cholesterol and total lipid in young female rats  

Microsoft Academic Search

Young adult female rats were fed diets containing 2% of calories from corn oil plus 20, 40, 60 or 80% of calories as beef\\u000a tallow or diets containing 2% corn oil and the calorie allowance restricted to 80, 60, 40 or 20% of ad libitum consumption.\\u000a Incorporation of C14-acetate into cholesterol and total fat was determined as an indication of

Jacqueline Dupont



Effect of Adrenalectomy on Mating-Induced Prolactin Surges and Pseudopregnancy in the Female Rat  

Microsoft Academic Search

In the estrous female rat, mating stimulation induces an acute surge of prolactin (PRL) within 20 min after mating followed by the onset of twice-daily PRL surges which persist for an 8- to 13-day period of acyclicity called pseudopregnancy. In Experiment 1, we examined whether the release of adrenal hormones after mating modulates mating-induced PRL secretion during the first 38

Nicole Cameron; Grace K. Ha; Mary S. Erskine



Effect of oral contraceptives on folate economy--a study in female rats.  


Daily administration of one tenth of a tablet of Ovulen-50 (ethinodiol diacetate, 1 mg, ethinylestradiol, 50 microgram) to adult female rats resulted in an increase in the liver and kidney folate levels, increased urinary excretion of folate and a fall in serum folate while red blood cell folate levels remained unaffected. The tissue folate levels did not indicate adverse effect of OCA on folate economy of the body. PMID:428912

Lakshmaiah, N; Bamji, M S



Toxicokinetics of the phytoestrogen daidzein in female DA\\/Han rats  

Microsoft Academic Search

Female DA\\/Han rats were given the phytoestrogen daidzein, either intravenously (10 mg\\/kg b.w.) or orally by gavage (10 or 100 mg\\/kg b.w.). The plasma concentration-time curve determined after i.v. administration of daidzein was fitted to a triexponential model, resulting in a final half-life (%-phase) of approximately 4 h. The oral bioavailability of 10 mg daidzein\\/kg was 9.7%, while that of

P. Janning; A. Upmeier; P. Diel; H. Michna; G. H. Degen; H. M. Bolt



(+)-Z-Bisdehydrodoisynolic Acid Ameliorates Obesity and the Metabolic Syndrome in Female ZDF Rats  

Microsoft Academic Search

Objective: The putative selective estrogen receptor modulator (+)-Z-bisdehydrodoisynolic acid (Z-BDDA) has been found to improve cardiovascular risk in rodents. The objective of this study was to investigate the effectiveness of (+)-Z-BDDA compared with the antidiabetic drug, rosiglitazone, in treating obesity and risk factors associated with the metabolic syndrome.Research Methods and Procedures: Female Zucker Diabetic Fatty rats were randomly assigned to

William J. Banz; Jeremy Davis; Jena J. Steinle; Stuart Adler; Jennifer Oitker; Todd A. Winters; D. Allan Higginbotham; Yuqing Hou; Nancy Henry; Richard Peterson; Cal Y. Meyers



Effect of growth hromone and estrogen administration on hepatocyte alterations in old ovariectomized female wistar rats  

Microsoft Academic Search

Aging could be due to the accumulation of oxidative damage. On the other hand, growth hormone (GH) and estrogen deficiency\\u000a induce deleterious effects on different tissues, and hormonal replacement could counteract these effects. We have investigated\\u000a whether GH and estrogen administration modify some parameters related to oxidative stress and inflammation in hepatocytes\\u000a isolated from old ovariectomized female rats. Twenty-two month-old

Carmen Castillo; Veronica Salazar; Carmen Ariznavarreta; Elena Vara; Jesus A. F. Tresguerres



Studies of tamoxifen as a promoter of hepatocarcinogenesis in female Fischer F344 rats  

Microsoft Academic Search

Tamoxifen, an antiestrogen used in the treatment of breast cancer, was assessed for carcinogenic potential in the two-stage model of experimental hepatocarcinogenesis. Groups of female Fischer F344 rats were initiated with a non-necrogenic, subcarcinogenic dose of diethylnitrosamine (DEN; 10 mg\\/kg, po) and fed tamoxifen at a concentration of 250 mg per kg of AIN-76A diet for 6 or 15 months.

Yvonne P. Dragan; Susan Fahey; Jennifer Vaughan; V. Craig Jordan; Henry C. Pitot



Antidepressants differentially modify the extinction of an aversive memory task in female rats.  


Treatment of major depression, posttraumatic stress disorder and other psychopathologies with antidepressants can be associated with improvement of the cognitive deficits related to these disorders. Although the mechanisms of these effects are not completely elucidated, alterations in the extinction of aversive memories are believed to play a role in these psychopathologies. We have recently verified that female rats present low levels of extinction when submitted to the plus-maze discriminative avoidance task. In the present study, female rats were treated long term with clinically used antidepressants (fluoxetine, nortriptyline or mirtazapine) and subjected to the plus-maze discriminative avoidance task to evaluate learning, memory, extinction and anxiety-related behaviors as well as behavioral despair in the forced swimming test. All groups learned the task and exhibited retrieval. Chronic treatment with fluoxetine (but not with the other antidepressants tested) increased extinction of the discriminative task. In the forced swimming test, the animals treated with fluoxetine and mirtazapine showed decreased immobility duration. In conclusion, fluoxetine potentiated extinction, while both fluoxetine and mirtazapine were effective in ameliorating depressive-like behavior in the forced swimming test, suggesting a possible dissociation between the effects on mood and the extinction of aversive memories in female rats. PMID:22310225

Melo, Thieza G; Izídio, Geison S; Ferreira, Luane S; Sousa, Diego S; Macedo, Priscila T; Cabral, Alícia; Ribeiro, Alessandra M; Silva, Regina H



Detecting early biomechanical effects of zoledronic Acid on femurs of osteoporotic female rats.  


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, Erika Veruska Paiva



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.

Palacio, Evandro Pereira; Muller, Sergio Swain; Sardenberg, Trajano; Mizobuchi, Roberto Ryuiti; Galbiatti, Jose Antonio; Durigan, Alcides; Savarese, Aniello; Ortolan, Erika Veruska Paiva



Pregnant Women  

Center for Food Safety and Applied Nutrition (CFSAN)

... to-Be What you need to know about food safety before, during, and after pregnancy. Preventing Listeriosis In Pregnant Hispanic Women in the US ... More results from


Effects of prenatal stress on lever-press acquisition with delayed reinforcement in male and female rats.  


The prenatally stressed (PS) rat shows enhanced conditioned fear and increased behavioral inhibition in response to footshock compared to control (CON) rats. It is unclear whether this facilitated learning will occur only with aversive stimulation, or if it will also be observed in the context of positive reinforcement. There are limited and inconsistent data regarding sex differences and the impact of prenatal stress on learning. The present study was designed to examine lever-press acquisition with a 10-s delay to food reinforcement in male and female PS and CON rats. Overall, twice as many PS male rats acquired the lever-press response than the PS female rats, CON male rats, and CON female rats. PS male rats also earned significantly more reinforcers and responded on the operative lever at a significantly greater rate than the other three rat groups. These findings suggest that PS rats exhibit altered learning with a task involving positive reinforcement, and this effect of PS is sex specific for male rats. PMID:22178450

Bruner, Natalie R; Salm, A K; Anderson, Karen G



Dietary quercetin exacerbates the development of estrogen-induced breast tumors in female ACI rats  

SciTech Connect

Phytoestrogens are plant compounds that structurally mimic the endogenous estrogen 17{beta}-estradiol (E{sub 2}). 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 E{sub 2}-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 E{sub 2} pellets, co-exposure to quercetin did not protect rats from E{sub 2}-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 + E{sub 2}-treated groups at the end of the experiment. Tumor latency was significantly decreased among rats from the quercetin + E{sub 2} group relative to those in the E{sub 2} group. Catechol-O-methyltransferase (COMT) activity was significantly downregulated in quercetin-exposed mammary tissue. Analysis of 8-isoprostane F{sub 2{alpha}} (8-iso-PGF{sub 2{alpha}}) levels as a marker of oxidant stress showed that quercetin did not decrease E{sub 2}-induced oxidant stress. These results indicate that quercetin (2.5 g/kg food) does not confer protection against breast cancer, does not inhibit E{sub 2}-induced oxidant stress and may exacerbate breast carcinogenesis in E{sub 2}-treated ACI rats. Inhibition of COMT activity by quercetin may expose breast cells chronically to E{sub 2} and catechol estrogens. This would permit longer exposure times to the carcinogenic metabolites of E{sub 2} and chronic exposure to oxidant stress as a result of metabolic redox cycling to estrogen metabolites, and thus quercetin may exacerbate E{sub 2}-induced breast tumors in female ACI rats.

Singh, Bhupendra [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Mense, Sarah M. [Department of Environmental Health Sciences, Columbia University, New York, NY 10032 (United States); Bhat, Nimee K. [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Putty, Sandeep; Guthiel, William A. [Division of Pharmaceutical Sciences, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States); Remotti, Fabrizio [Department of Pathology, Columbia University, New York, NY 10032 (United States); Bhat, Hari K., E-mail: bhath@umkc.ed [Division of Pharmacology and Toxicology, School of Pharmacy, University of Missouri-Kansas City, Kansas City, MO 64108 (United States)



Age-related Changes in the Serotonin 2A Receptor in the Hypoglossal Nucleus of Male and Female Rats  

PubMed Central

Hypoglossal motoneuron output to the genioglossus muscle contributes to upper airway patency. Serotonin (5HT) plays an important role in regulating hypoglossal motoneuron excitability via serotonin 2A receptors (5HT2A). The purpose of this study was to investigate whether there are age-associated changes in 5HT2A receptor expression in the hypoglossal nucleus of male and female rats. The brains of young, middle-aged and old F344 rats were sectioned, reacted immunocytochemically for the presence of 5HT2A receptor, and the staining density quantified. The estrus stage of female rats was determined and circulating sex hormone levels measured and correlated with 5HT2A levels. The results show that there was significantly greater 5HT2A receptor immunoreactivity in the hypoglossal nucleus of female than of male rats. With increasing age, there was an increase in 5HT2A receptor immunoreactivity in the hypoglossal nucleus of female rats, whereas no age-associated changes were observed in male rats. Previous studies have shown a reduction in 5HT-dependent respiratory plasticity and an age-associated decrease in 5HT in the hypoglossal nucleus in male but not female rats. Data from the present study suggest that aging male rats fail to compensate adequately for reduced 5HT in the hypoglossal nucleus by upregulating the expression of the 5HT2A receptor.

Seebart, Benjamin R.; Stoffel, Ryan T.; Behan, Mary



Pelvic Organ Distribution of Mesenchymal Stem Cells Injected Intravenously after Simulated Childbirth Injury in Female Rats  

PubMed Central

The local route of stem cell administration utilized presently in clinical trials for stress incontinence may not take full advantage of the capabilities of these cells. The goal of this study was to evaluate if intravenously injected mesenchymal stem cells (MSCs) home to pelvic organs after simulated childbirth injury in a rat model. Female rats underwent either vaginal distension (VD) or sham VD. All rats received 2 million GFP-labeled MSCs intravenously 1 hour after injury. Four or 10 days later pelvic organs and muscles were imaged for visualization of GFP-positive cells. Significantly more MSCs home to the urethra, vagina, rectum, and levator ani muscle 4 days after VD than after sham VD. MSCs were present 10 days after injection but GFP intensity had decreased. This study provides basic science evidence that intravenous administration of MSCs could provide an effective route for cell-based therapy to facilitate repair after injury and treat stress incontinence.

Cruz, Michelle; Dissaranan, Charuspong; Cotleur, Anne; Kiedrowski, Matthew; Penn, Marc; Damaser, Margot



Effects of peripheral ? opioid receptor activation on inflammatory mechanical hyperalgesia in male and female rats  

PubMed Central

Activation of peripheral ? opioid receptors (KOR) effectively relieves pain and hyperalgesia in preclinical and clinical models of pain. Although centrally located KOR activation results in sexually dimorphic effects, it is unclear whether peripheral KOR also produces sex dependent effects in persistent inflammatory pain conditions. In this study, we investigated whether local administration of a specific KOR agonist, U50, 488 relieve mechanical hyperalgesia induced by the injection of complete Freund’s adjuvant (CFA) in the rat hindpaw, and whether there are sex differences. The effects of U50, 488 were assessed three days after the induction of CFA-induced inflammation, a time point at which mechanical hyperalgesia was most prominent. There were no sex differences in baseline and CFA-induced changes in mechanical thresholds between male and female rats. Local treatment of U50, 488 produced moderate, but significant, anti-hyperalgesia in both male and female rats. However, U50, 488 was significantly more effective in male rats at the highest dose of U50, 488. We confirmed that the highest dose of U50, 488 used in this study did not produce systemic effects, and that the drug effect is receptor specific. On the basis of these results, we suggest that local KOR agonists are effective in mitigating mechanical hyperalgesia under a persistent inflammatory pain condition and that sex differences in anti-hyperalgesic effects become more evident at high doses.

Auh, Q-Schick; Ro, Jin Y.



Effects of peripheral ? opioid receptor activation on inflammatory mechanical hyperalgesia in male and female rats.  


Activation of peripheral ? opioid receptors (KOR) effectively relieves pain and hyperalgesia in preclinical and clinical models of pain. Although centrally located KOR activation results in sexually dimorphic effects, it is unclear whether peripheral KOR also produces sex dependent effects in persistent inflammatory pain conditions. In this study, we investigated whether local administration of a specific KOR agonist, U50, 488 relieve mechanical hyperalgesia induced by the injection of complete Freund's adjuvant (CFA) in the rat hindpaw, and whether there are sex differences. The effects of U50, 488 were assessed three days after the induction of CFA-induced inflammation, a time point at which mechanical hyperalgesia was most prominent. There were no sex differences in baseline and CFA-induced changes in mechanical thresholds between male and female rats. Local treatment of U50, 488 produced moderate, but significant, anti-hyperalgesia in both male and female rats. However, U50, 488 was significantly more effective in male rats at the highest dose of U50, 488. We confirmed that the highest dose of U50, 488 used in this study did not produce systemic effects, and that the drug effect is receptor specific. On the basis of these results, we suggest that local KOR agonists are effective in mitigating mechanical hyperalgesia under a persistent inflammatory pain condition and that sex differences in anti-hyperalgesic effects become more evident at high doses. PMID:22819973

Auh, Q-Schick; Ro, Jin Y



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


A Comparison of the Risk Characteristics of Ever-Pregnant and Never-Pregnant SexuallyActive Adolescents  

Microsoft Academic Search

This article describes the risk behaviors of a sample of sexually active, urban African American adolescent females, and examines the differences between adolescents who havebeen pregnant (ever-pregnant) and adolescents who have not been pregnant (never-pregnant). Of the 279 young women interviewed, 48% had a history of pregnancy. Logistic regression indicated that adolescents who had a history of pregnancy engaged in

Lisa Bond; Karlene Lavelle; Jennifer Lauby



Neonatal xenoestrogen exposure alters growth hormone-dependent liver proteins and genes in adult female rats.  


The hypothalamic-growth hormone (GH)-liver axis represents a new concept in endocrine regulation of drug toxicity. Preponderant sex differences are found in liver gene expression, mostly dependent on the sexually dimorphic pattern of GH secretion which is set during the neonatal period by gonadal steroids. We tested if GH-dependent sexually dimorphic liver enzymes and proteins was perturbed by neonatal Bisphenol A (BPA) treatment in female rats. Female rats were sc injected with BPA (50 or 500 ?g/50 ?l) or castor oil vehicle from postnatal day 1 to 10. At five months serum prolactin, pituitary GH, and serum and liver insulin growth factor-I (IGF-I) were measured by RIA. Major urinary proteins (MUPs) were determined by electrophoresis. Liver Cyp2c11, Cyp2c12, Adh1, Hnf6, and Prlr mRNA levels were determined by real time PCR. Pituitary GH content and liver IGF-I concentration were increased by neonatal BPA treatment, indicating partial masculinization of the GH axis in treated females. GH-dependent female predominant liver enzyme genes (Cyp2c12 and Adh1) and a transcription factor (Hnf6) were downregulated or defeminized, while there were no changes in a male predominant gene (Cyp2c11) or protein (MUP). Our findings indicate that perinatal exposure to BPA may compromise the sexually dimorphic capacity of the liver to metabolize drugs and steroids. PMID:22842222

Ramirez, Maria Cecilia; Bourguignon, Nadia Soledad; Bonaventura, Maria Marta; Lux-Lantos, Victoria; Libertun, Carlos; Becu-Villalobos, Damasia



Amphetamine effects on startle gating in normal women and female rats  

PubMed Central

Background Dopamine agonists disrupt prepulse inhibition (PPI) of startle in male rodents. In humans, this is observed only in some studies. We reported that PPI was disrupted by D-amphetamine in men, but only among those with high basal PPI levels. Here, amphetamine effects on PPI were tested in normal women and female rats. Materials and methods Acoustic startle and PPI were tested in normal women after placebo or 20 mg amphetamine, in a double-blind, crossover design, and in female rats after vehicle or 4.5 mg/kg amphetamine. Rats were from Sprague–Dawley (SD) and Long Evans (LE) strains that differ significantly in gene expression in PPI-regulatory circuitry, including levels of nucleus accumbens (NAC) catechol-O-methyl transferase (COMT) mRNA. Results Amphetamine was bioactive in humans based on quantitative autonomic and self-rating measures, but did not significantly change startle magnitude or PPI across all subjects. Amphetamine’s effects on PPI in women correlated significantly (p<0.0008) with placebo PPI levels (reducing PPI only in women whose basal PPI levels exceeded the sample median) and with measures of novelty and sensation seeking. Amphetamine decreased PPI in SD rats that have relatively low NAC COMT gene expression and increased PPI in LE rats that have relatively high NAC COMT gene expression. Conclusion The dopaminergic regulation of PPI in humans is related to basal levels of sensorimotor gating and to specific personality traits in normal men and women. In rats, the effects of amphetamine on PPI differ significantly in strains with low vs. high NAC COMT expression.

Talledo, Jo A.; Sutherland Owens, Ashley N.; Schortinghuis, Tijmen



A role for hippocampal actin rearrangement in object placement memory in female rats.  


Actin rearrangement, the polymerization of globular actin (G-actin) to filamentous actin, causes morphological changes in dendritic spines and is hypothesized to be a substrate of learning and memory. The ovarian hormone estradiol promotes hippocampal actin rearrangement and enhances performance on hippocampus-dependent tasks, including object placement memory. The goals of the current study were to determine a role for actin rearrangement and its regulatory pathway in object placement memory in female rats and to determine if estradiol impacts actin rearrangement in ovariectomized rats during the performance of the task. In an initial experiment, young adult Long-Evans rats were ovariectomized and implanted with capsules containing either cholesterol vehicle or estradiol. Bilateral intrahippocampal infusions of aCSF vehicle or the actin rearrangement inhibitor, latrunculin A, were administered 15 min prior to initiation of the object placement task. Latrunculin A dose-dependently impaired object placement memory. Estradiol had no impact on the ability of latrunculin A to affect performance. In a second experiment, rats were ovariectomized and received implants containing cholesterol or estradiol. Half of each hormone treatment group was exposed to the object placement memory task and half underwent control procedures. Immediately following completion of behavior, rats were euthanized and hippocampi removed. Western blotting was used to measure hippocampal levels of phosphorylated and total levels of a regulator of actin polymerization, the actin depolymerization factor cofilin. Exposure to the object placement memory task resulted in significant increases in phosphorylated levels of cofilin. Estradiol treatment had no impact on protein levels. These data support a role for hippocampal actin rearrangement and its regulatory proteins in object placement memory in female rats and suggest that chronic estradiol treatment does not impact hippocampal actin arrangement. PMID:23010136

Nelson, Britta S; Witty, Christine F; Williamson, Elizabeth A; Daniel, Jill M



[Effect of individual peculiarities on formation of preference of ethanol in female and male Wistar rats].  


Individual characteristics of animal behavior can serve a prognostic parameter of predisposition to use of alcohol. The goal of the work was to study dynamics of formation of preference of alcohol at early stages in the process of forced alcoholization in male and female rats as well as the accompanying changes in behavior parameters. For 3 months, the rats were submitted to the forced alcoholization with 10 % ethanol. Each week the rats were tested in the "two-glass trial". Individual peculiarities of all animals were evaluated prior to, after 6 weeks, and after the end of the experiment with aid of the "open field test" and "Suok-test". Results showed that the male rats demonstrating by the end of the experiment the significantly higher level of the alcohol preference, at the initial stages of the forced alcoholization demonstrated the significantly lower preference as compared with the remaining ones. These rats also showed the lower levels of the motor and exploratory activities before alcoholization as compared with control. On the contrary, the individuals that by the end of the experiment did not differ from control by the level of the alcohol preference demonstrated prior to alcoholization in the "Suok-test" the higher anxiety level. In female groups, no statistically significant differences were observed both in parameters of the motor and exploratory activities and in the anxiety level in both tests. Thus, in male rats, the prognostic parameter predicting formation of the abuse can serve the degree of alcohol preference at the initial stages. PMID:22145323

Filatova, E V; Egorov, A Iu; Kucher, E O; Kulagina, K O


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 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.

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



Biochemical and histologic presentations of female wistar rats administered with different doses of paracetamol/methionine.  


This study was carried out to compare the hepatoprotective effect of methionine on paracetamol treated rats at both the peaks of toxicity and absorption. Female Wistar rats were divided into 17 groups consisting of eight rats per group and treated with different doses of paracetamol/methionine (5:1). Each control rat received 5 ml of physiologic saline. The study was terminated at two different end points -the 4th and 16th hours. Results show that rats administered with toxic doses (1000 mg/kg, 3000 mg/kg, 5000 mg/kg BW) of paracetamol exhibited significant increases in the levels of ALT, AST, ?- GT compared with controls. These increases were much higher at the 16th than 4th hour but serum total protein, albumin and globulin were significantly decreased by the end of the 16th hour. Histology results of rats in the 3000 and 5000 mg/kg (by the end of the 16th hour) confirmed hepatic damage, light microscopic evaluation of liver showed remarkable centrilobular necrosis. Moreover, the presence of mononuclear cells in liver section of rats intoxicated with APAP (5000 mg/kg) suggests a possible involvement of inflammatory process which resulted in regurgitation of bilirubin leading to its elevated level as well as increase activity of ALP. The hepatoprotective effect of methionine, on the other hand, was demonstrated in these rats at the 4th and 16th hours, and both results were comparable and therefore not significantly different but elevation in GGT level still persisted. In conclusion, data obtained from this study suggest that these agents may be capable of inducing GGT, although further study is required to establish a possible relationship between methionine and this enzyme in some other animal species. PMID:22547184

Iyanda, A A; Adeniyi, F Aa



Prenatal corticosterone increases spontaneous and d-amphetamine induced locomotor activity and brain dopamine metabolism in prepubertal male and female rats  

Microsoft Academic Search

Recently, both glucocorticoid receptor immunoreactivity and glucocorticoid receptor messenger RNA levels were found in multiple brain areas, especially in the neuroepithelium during the late prenatal development of the rat brain. To better understand the potential influence of stress on fetal brain development by release of maternal adrenocortical steroids, we have investigated the effects of corticosterone administration to pregnant rats on

R. Diaz; S. O. Ögren; M. Blum; K. Fuxe




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...


Antispasmodic Effects of Aqueous and Hydroalcoholic Punica granatum Flower Extracts on the Uterus of Non-pregnant Rats  

PubMed Central

Background Punica granatum Linn. (PG) is native to the Mediterranean region. Its flower exhibited antioxidant activity. The present study attempt to investigate the effect of these extract on uterine contraction and its possible mechanism(s). Methods Thirty five female Wistar rats (200–300 g) at estrous phases of cycle was examined in this study; pieces of virgin adult rat uterus (1.5 cm) were suspended in an organ bath containing 10 ml of De Jalon solution at 29 °C. Tissue contractility was isometrically recorded. KCl (60 mM), BaCl2 (4 mM) and oxytocin (10 mU/ml) were applied to the tissue in the presence and absence of aqueous and hydroalcoholic extracts of the plant (0.05, 0.1, 0.2, 0.4 and 0.8 mg/ml). Propranolol (1 µM) and naloxane (1 µM) were added in KCl induced contractions. The results were analyzed by ANOVA and p < 0.05 were considered as significant. Results Cumulative concentration of extracts reduced uterine contractions induced by KCl dose-dependently (p < 0.01). Extracts in a dose dependent (p < 0.05) reduced uterine contractions decreased dose-dependently after of addition oxytocin. The extracts added cumulatively to the organ bath reduced contractions but they did not affect uterine contractions induced by BaCl2 except the last dose. Spasmolytic effects of the extracts were not affected by propranolol or naloxane in KCl induced contractions. Conclusion Extracts diminished K+-induced contraction in uterus, therefore it seems that substances that decrease K+-induced contraction can also block voltage dependent calcium channel. The extracts did not have any effect on ?-adrenoceptors or potassium channels.

Ahangarpour, Akram; Heidari, Razieh; Abdolahzadeh, Mahsa; Oroojan, Ali Akbar



Evaluation of sex difference in tissue repair following acute carbon tetrachloride toxicity in male and female Sprague–Dawley rats  

Microsoft Academic Search

Cellular regeneration and tissue repair greatly influence the outcome of acute carbon tetrachloride (CCl4) hepatotoxicity. This study examined the temporal kinetics of cellular regeneration and tissue repair processes in male and female Sprague–Dawley (SD) rats following an acute CCl4 exposure (0.8 ml\\/kg, i.p.). In female rats, hepatic damage peaked at 24 h following the treatment and was ?2.5-fold (AST 2.7-fold,

Abdollah P. Moghaddam; Jeffrey S. Eggers; Edward J. Calabrese



Potential estrogenic effect(s) of parabens at the prepubertal stage of a postnatal female rat model  

Microsoft Academic Search

In this study, a female pubertal assay on the effects of parabens, including methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutylparaben, was performed in a female Sprague–Dawley rat model during the juvenile-peripubertal period. The rats were orally treated with these parabens from postnatal day 21–40 in a dose-dependent manner (62.5, 250 and 1000mg\\/kg body weight [BW]\\/day). 17?-Ethinylestradiol (1mg\\/kg BW\\/day) was used

Thuy T. B. Vo; Yeong-Min Yoo; Kyung-Chul Choi; Eui-Bae Jeung



Short-term weight cycling in aging female rats increases rate of weight gain but not body fat content  

Microsoft Academic Search

OBJECTIVE: To examine the effects of short-term repeated weight cycling (WC) above and below the baseline (BL) body weight (BW) on body weight regulation, feeding efficiency, and fat content in old female Wistar rats when dietary fat content was kept constant.DESIGN: Completely randomized.ANIMALS AND METHODS: Female Wistar rats, 11 months old at the beginning of the study, were randomly divided

MA Pellizzon; AM Buison; K-LC Jen



Deficits in Progesterone-Facilitated Sexual Behaviors and Forebrain Estrogen and Progestin Receptors in Obese Female Zucker Rats  

Microsoft Academic Search

Obese female Zucker rats (fa\\/fa) are sterile. Among their reproductive abnormalities is hyporesponsiveness to the stimulatory effects of ovarian steroid hormones on sexual behaviors. This study was designed to test the hypothesis that obese Zucker females are deficient in hypothalamic\\/preoptic area estrogen receptors (ERs) and\\/or estradiol-induced progestin receptors (PRs). Ovariectomized (OVX) lean and obese Zucker rats were tested for the

Deborah H. Olster; Ilene D. Auerbach



Antioxidant defense system in lung of male and female rats: Interactions with alcohol, copper, and type of dietary carbohydrate  

Microsoft Academic Search

Male and female rats were used to investigate the effects of type of dietary carbohydrate (CHO), copper, and ethanol consumption on lung antioxidant enzyme activities and levels of phosphorylated compounds in whole blood. Copper-deficient female rats exhibited a greater degree of copper deficiency than males, as assessed by hepatic copper concentration and hepatic copper superoxide dismutase (CuSOD) activity. However, copper-deficient

Meira Fields; Charles G. Lewis; Mark D. Lure




Microsoft Academic Search

The purpose of this study was to evaluate the safety of a Thai medicinal plant, Aegle marmelos, and a non-caloric sweetener, Stevia rebaudiana, on the reproduction of female rats. Female rats were treated orally with aqueous extract of A. marmelos (6%) and S. rebaudiana at various concentrations (0, 0.2, 1, or 10%) for 60 days (1 ml\\/day) before mating. The

Kanokporn Saenphet; Salika Aritajat; Supap Saenphet; Jeeradej Manosroi; Aranya Manosroi


A Histochemical, Morphometric and Ultrastructural Study of Gastrocnemius and Soleus Muscle Fiber Type Composition in Male and Female Rats  

Microsoft Academic Search

The fiber type composition of gastrocnemius and soleus muscles of adult male and female rats was examined by histochemical, morphometric and ultrastructural methods. Six male and 6 female, 3.5-month-old rats were used in the study. The fiber types were determined using the adenosine triphosphatase (ATPase) and succinate dehydrogenase (SDHase) staining techniques. The number of fibers of different types and the

I. Ustunel; R. Demir



Hormonal control of Luteal 20alpha-Hydroxy steroid dehydrogenase and delta5-3beta-hydroxy steroid dehydrogenase during luteolysis in the pregnant rat.  


Treatment of pregnant rats with human chorionic gonadotrophin, luteotrophin (luteinizing hormone), luteotrophin-releasing hormone, prostaglandin F2alpha, aminoglutethimide, or by foetoplacental removal or hysterectomy achieved a common multiple-response pattern, namely increased activity of luteal 20alpha-hydroxy steroid dehydrogenase with decreased activity of delta5-3beta-hydroxy steriod dehydrogenase and release of delta4-3-oxo steroids in vitro. 2. Similar effects of foetoplacental removal are noted in pregnant mice. 3. Gonadotrophin induced lower activities of 20alpha-hydroxy steroid dehydrogenase, except at the very end of pregnancy, and partly inhibited the induction caused by foetoplacental removal. 4. The results suggest that existence of a placental factor that restrains these changes until the end of normal pregnancy, which is produced in amounts proportional to the number of placentae and is conveyed to the ovary via the blood. 5. This factor was not replaced by prolactin. 6. It is argued that neither placental lactogen nor pituitary luteotrophin participate in the induction of 20alpha-hydroxy steroid dehydrogenase at late pregnancy in the rat. 7. Aminoglutethimide induced 20alpha-hydroxy steroid dehydrogenase only in late pregnancy. This was partly reversed by progesterone, wholly reversed by progesterone plus oestrogen, and did not involve the pituitary. PMID:776170

Rodway, R G; Kuhn, N J



Effects of Stimulation and Blockade of D2 Receptor on Depression-Like Behavior in Ovariectomized Female Rats  

PubMed Central

The aim of the present study was to explore the hedonic effects of D2 receptor agonist, quinpirole and D2 receptor antagonist, and sulpiride alone or in combination with a low dose of 17?-E2-estradiol (17?-E2) in the adult ovariectomized female rats (OVX). OVX rats of Wistar strain were used in all experiments. Two weeks after surgery rats were chronically treated with vehicle, a low dose of 17?-E2 (5.0??g/rat), quinpirole (0.1?mg/kg), sulpiride (10.0?mg/kg), quinpirole plus 17?-E2, or sulpiride plus 17?-E2 for 14 days before the forced swimming test. We found that sulpiride significantly decreased immobility time in the OVX females. A combination of sulpiride with a low dose of 17?-E2 induced more profound decrease of immobility time in the OVX rats compared to the rats treated with sulpiride alone. On the contrary, quinpirole failed to modify depression-like behavior in the OVX rats. In addition, quinpirole significantly blocked the antidepressant-like effect of 17?-E2 in OVX rats. Thus, the D2 receptor antagonist sulpiride alone or in combination with a low dose of 17?-E2 exerted antidepressant-like effect in OVX female rats, while the D2 receptor agonist quinpirole produced depressant-like profile on OVX rats.

Fedotova, Julia



Effects of early rearing conditions on cognitive performance in prepubescent male and female rats.  


The interactions between a mother and her offspring during early postnatal life impact cognitive development in altricial species. The current study examined the influence of postnatal rearing conditions on subsequent cognitive functioning in male and female Long-Evans rats prior to puberty. Maternal conditions were manipulated by repeated separations of rat pups from their dams on postnatal days 2 though 14. In the early handling condition, pups were removed from mothers briefly for 15min daily, while in the maternal separation condition pups were separated from their mothers for 180min daily. Offspring from handled or separated litters were evaluated prior to puberty between days 25-36 of life on a battery of cognitive tasks that assessed several types of memory. Male rats separated from mothers for 180min were impaired in their non-spatial and spatial memory compared to early-handled males as indicated by their performance on an object recognition task, a Y-maze task, and reference and working memory versions of the water maze task. In contrast, maternally-separated females were not impaired, and in some cases performed better on memory tasks, compared to early-handled females. Results indicate that the biological sex of offspring moderated the effects of maternal conditions on diverse cognitive tasks. Because sex differences were evident prior to puberty, gonadal hormones likely had a limited influence on cognition. Although the bases for sex differences in the cognitive response to rearing conditions are unknown, disparities in maternal attentiveness directed toward male and female offspring may play a role. PMID:20403447

Frankola, Kathryn A; Flora, Arianna L; Torres, Amanda K; Grissom, Elin M; Overstreet, Stacy; Dohanich, Gary P



Male and female rats express similar blood pressure responses to "push-pull" gravitational stress.  


Brief exposure to -G(z) ("push") reduces eye-level blood pressure (elbp) during subsequent exposure to +G(z) ("pull"). This is called the "push-pull effect." To evaluate the influence of gender and the axis of rotation (pitch vs. roll) on the push-pull effect, 10 isoflurane-anesthetized male and 10 female Sprague-Dawley rats were restrained supine on a heated tilt board. Rats were subjected to two G profiles: a control profile consisting of rotation from 0 G(z) to 90 degrees head-up tilt (+1 G(z)) for 10 s and a push-pull profile consisting of rotation from 0 G(z) to 90 degrees head-down tilt (-1 G(z)) for 2 s immediately preceding 10 s of +1 G(z) stress. A total of 16 tilts consisting of equal numbers of control and push-pull trials and equal numbers of pitch and roll rotations were imposed by using a counterbalanced design. Gender exerted a significant effect on baseline (0 G(z)) ELBP (pressure was approximately 4 mmHg higher in females). In males and females, ELBP rose to a similar extent ( approximately 8 mmHg) during push, fell to a similar extent (approximately 18 mmHg) during control +G(z) stress, and fell to a similar extent (approximately 22 mmHg) during push-pull +G(z) stress. Altering the axis of rotation between the x-axis (roll) and the y-axis (pitch) did not influence the results. Thus males and females exhibit a push-pull effect; however, gender and axis of rotation do not appear to influence the push-pull effect in anesthetized rats subjected to tilting. PMID:12433935

Hakeman, Amy L; Sheriff, Don D



Acute predator stress impairs the consolidation and retrieval of hippocampus-dependent memory in male and female rats  

PubMed Central

We have studied the effects of an acute predator stress experience on spatial learning and memory in adult male and female Sprague-Dawley rats. All rats were trained to learn the location of a hidden escape platform in the radial-arm water maze (RAWM), a hippocampus-dependent spatial memory task. In the control (non-stress) condition, female rats were superior to the males in the accuracy and consistency of their spatial memory performance tested over multiple days of training. In the stress condition, rats were exposed to the cat for 30 min immediately before or after learning, or before the 24-h memory test. Predator stress dramatically increased corticosterone levels in males and females, with females exhibiting greater baseline and stress-evoked responses than males. Despite these sex differences in the overall magnitudes of corticosterone levels, there were significant sex-independent correlations involving basal and stress-evoked corticosterone levels, and memory performance. Most importantly, predator stress impaired short-term memory, as well as processes involved in memory consolidation and retrieval, in male and female rats. Overall, we have found that an intense, ethologically relevant stressor produced a largely equivalent impairment of memory in male and female rats, and sex-independent corticosterone-memory correlations. These findings may provide insight into commonalities in how traumatic stress affects the brain and memory in men and women.

Park, Collin R.; Zoladz, Phillip R.; Conrad, Cheryl D.; Fleshner, Monika; Diamond, David M.



Carbon dioxide, but not isoflurane, elicits ultrasonic vocalizations in female rats.  


Gradual filling of a chamber with carbon dioxide is currently listed by the Canadian Council on Animal Care guidelines as a conditionally acceptable method of euthanasia for rats. Behavioural evidence suggests, however, that exposure to carbon dioxide gas is aversive. Isoflurane is less aversive than carbon dioxide and may be a viable alternative, though objective data are lacking for the period leading up to loss of consciousness. It has been shown that during negative states, such as pain and distress, rats produce ultrasonic vocalizations. The objective of this study was to detect ultrasonic vocalizations during exposure to carbon dioxide gas or isoflurane as an indicator of a negative state. Specialized recording equipment, with a frequency detection range of 10 to 200 kHz, was used to register these calls during administration of each agent. Nine female Sprague-Dawley rats were exposed to either carbon dioxide or isoflurane on two different occasions. All rats vocalized in the ultrasonic range (30 to 70 kHz) during exposure to carbon dioxide. When exposed to isoflurane, no calls were detected from any of the animals. The frequent occurrence of ultrasonic vocalizations during carbon dioxide exposure suggests that the common practice of carbon dioxide euthanasia is aversive to rats and that isoflurane may be a preferable alternative. PMID:23828852

Chisholm, J; De Rantere, D; Fernandez, N J; Krajacic, A; Pang, D S J



Intra-striatal estradiol in female rats impairs response learning within two hours of treatment.  


Estradiol treatment administered systemically or directly to the dorsolateral striatum across two days impairs performance on a response task in which rats learn to make a specific body turn to locate food on a maze. Estradiol can act through both slow and rapid signaling pathways to regulate learning impairments, however it is impossible to dissociate the slow from the rapid contributions of estradiol following long exposures. To assess the rapid effects of estradiol on striatum-sensitive learning, we trained rats on a response learning task after either relatively short or long treatments of estradiol infused directly into the striatum. Three-month-old female rats were ovariectomized 21 days before training and received guide cannulae implanted bilaterally into the dorsolateral striatum. For short duration treatments, rats were given bilateral infusions (0.5 ?l) of 17?-estradiol-sulfate (0, 5, 50, or 500 nM in aCSF-vehicle) either 2h or 15 min prior to training. For long duration treatments, rats received a series of estradiol infusions (500 nM) at 48, 24, and 2h prior to training. Replicating previous findings (Zurkovsky et al., 2007), intra-striatal estradiol treatments given for two days prior to training impaired response learning. Estradiol-induced impairments in performance were also demonstrated 2h, but not 15 min, after single infusions. Thus, estradiol acts within hours of exposure in the striatum, a structure lacking classical estrogen receptors, to impair response learning. PMID:21820439

Zurkovsky, L; Serio, S J; Korol, D L



Modulatory effect of cod liver oil on bone mineralization in overiectomized female Sprague Dawley rats.  


Osteoporosis represents a major public health problem through its association with fragility fractures, primarily of the hip, spine and distal forearm. The risk of osteoporosis increased in postmenopausal women due to decline in estrogen levels. Replicable hormone therapy is associated with undesirable side effects. Cod liver oil (CLO) is a rich source of docosahexaenoic acid eicosapentaenoic acid linolenic acid and vitamins A, E and D. In this study, the effect of CLO will be tested in the prevention of bone loss in the ovariectomized (OVX) female rats. One group of OVX rats (n = 12) received an estrogen implantation at the time of operation and the second group was supplemented orally with CLO (200 ?l/kg body weight) daily for 8 weeks. At the end of the experiment, blood was analysed for serum calcium, phosphorous, bone-specific alkaline phosphatase, osteocalcin and estrogen and femur for calcium determination. Estrogen implantation as well as CLO supplementation in OVX rats increased the calcium level in femur as compared with sham rats (p < 0.05). It is concluded that supplementation of CLO have a positive effect on bone mineralization in rat, and this could offer a new strategy to avoid the side effects of replaceable hormonal therapy. PMID:22033426

Moselhy, Said S; Al-Malki, Abdulrahman L; Kumosani, Taha A; Jalal, Jalaluddin A



Chronically stressed female rats show increased anxiety but no behavioral alterations in object recognition or placement memory: a preliminary examination.  


Stress, depending on intensity and duration, elicits adaptive or maladaptive physiological effects. Increasing evidence shows those patterns of advantageous versus deleterious physiologic stress effects also exist for some brain functions, including learning and memory. For example, short stress enhances, while chronic stress impairs, performance on numerous cognitive tasks in male rats. In contrast, performance of female rats is enhanced, or not altered, following both short-term and long-term stress exposure on the same behavioral tasks. The current study was designed to better characterize the behavioral effects of sustained chronic restraint stress in female rats. Female Sprague Dawley rats were assigned to a stress (restraint, 6 h/day, 35 days) or control (no stress) condition, weighed weekly, and then tested on open field (OF), object recognition (OR) and object placement (OP) tasks. Stressed females gained less weight during stress than controls. On the OF, there were no group differences in locomotor activity, but stressed females made fewer inner visits than controls, indicating increased anxiety. Both groups successfully performed the OP and OR tasks across all inter-trial delays, indicating intact non-spatial and spatial memory in both control and stress females. The current results provide preliminary evidence that the commonly used chronic restraint stress model may not be an efficient stressor to female rats. PMID:22168672

Bowman, R E; Kelly, R



Modulation in reproductive tissue redox profile in sexually receptive female rats after short-term exposure to male chemical cues.  


It is well known that antioxidants play an important role in sperm fertility, but there is no data on the literature regarding the effect of male chemical cues in the antioxidant defenses of the female reproductive tract. Here, we evaluated oxidative parameters in ovaries and uterus of virgin female rats isolated from contact to males and exposed only to male-soiled bedding (MSB). Four-month-old Wistar (regular 4-day cyclic) virgin female rats were utilized from proestrus to estrus phase of the reproductive cycle for experimental exposure. In an isolated room, female rats were exposed for 90 min to MSB. For biochemical assays, female rats were killed by decapitation at 30, 90, 180, and 240 min after the end of exposure, and the ovaries and uterus were removed for further analysis. Antioxidant enzyme activities (superoxide dismutase, catalase, and glutathione peroxidase), the nonenzymatic antioxidant potential (total radical-trapping antioxidant parameter), and the oxidative damage parameters (thiobarbituric acid-reactive species and carbonyl content) were analyzed. We observed an increase in the nonenzymatic antioxidant potential and diminished free radical oxidative damage in uterine tissue, 30 and 90 min after exposure. Furthermore, in ovaries, enzymatic defenses were modulated distinctly along the 240 min after exposure. MSB exposure modulates the antioxidant profile in ovaries and uterus of receptive female rats. It is possible that the modifications in the oxidative profile of the female genital tract may have important implications in the process of fertilization. PMID:19188278

Behr, Guilherme Antônio; da Motta, Leonardo Lisbôa; de Oliveira, Marcos Roberto; Oliveira, Max William Soares; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca



Developmental changes in choline acetyltransferase and glutamate decarboxylase activity in various regions of the brain of the male, female, and neonatally androgenized female rat  

Microsoft Academic Search

In an attempt to discern effects of sex hormones on the development of neurotransmitter systems in the rat brain, choline acetyltransferase (ChAT) and glutamate decarboxylase (GAD) have been measured at postnatal days 8, 12, 25, and 60 in five regions (amygdala, anterior hypothalamus, hippocampus, olfactory bulbs, and cerebral cortex) of the brains of normal male, normal female, and neonatally androgen-treated

R. Brown; B. W. L. Brooksbank



Effects of aqueous extract of Aspilia africana on reproductive functions of female Wistar rats.  


Effects of Aspilia africana leaf extract on oestrous cycle and ovulation were studied in adult female Wistar strain rats. Cyclic female rats weighing 150 to 200 g were divided into two study groups: the oestrous study and ovulation study group. For the oestrous study, the experimental group received 500 mg kg(-1) b. wt. of the extract for 14 days while the control group received distilled water for the same period. In both groups, vaginal lavage was taken daily from the 5th day to monitor the oestrous cycle. For the ovulation study, there was a control group and two experimental groups. The control group received distilled water while group 1 and 2 received 500 and 1000 mg kg(-1) b.wt. of Aspilia africana leaf extract for 16 days, respectively. The animals were sacrificed on the estrous following the treatment. The results showed a significant decrease in the body weight of the treated rats (p = 0.01) and the oestrous cycle was altered after the commencement of extract. This was indicated by the prolonged proestrous and a reduced dioestrus and estrus. There was a dose-dependent reduction in the ovulation s shown by the reduced number of ova observed in the oviduct from the treated rats compared with control (p<0.05). The extract caused inflammation of the fallopian tube, degeneration in the ovarian cortex in the stroma cells of the ovary and disruption of the endometrium of the uterus. Results suggest that aqueous extract of Aspilia africana leaf has antifertility effect by altering oestrous cycle and causing a dose dependent adverse effect on ovulation in Wistar strain rats. PMID:20437701

Oyesola, T O; Oyesola, O A; Okoye, C S



Are the neuroprotective effects of estradiol and physical exercise comparable during ageing in female rats?  


Ageing of the brain is accompanied by variable degrees of cognitive decline. Estrogens have profound effects on brain ageing by exerting neurotrophic and neuroprotective types of action. Furthermore, exercise has also been claimed to play a role in the non-pharmacological prevention of psycho-neuronal decline with ageing. In the present study the question was asked whether chronic physical exercise might substitute the action of estrogens in aged rats. We compared the effects of 17?-estradiol (E2) treatment and long-term moderate physical exercise in ageing (15 months, early stage of ageing) and old (27 months) female rats, on cognitive functions and the relevant intracellular molecular signaling pathways in the hippocampus. Results showed that both treatments improved attention and memory functions of the 15 months old rats. Like E2, physical training enhanced the level of brain derived nerve growth factor and the activation of PKA/Akt/CREB and MAPK/CREB pathways. The treatments also enhanced the levels of synaptic molecules synaptophysin and synapsin I, which could explain the improved cognitive functions. In the 27 months old rats the behavioral and molecular effects of E2 were indistinguishable from those found in the 15 months old animals but the effects of physical exercise in most of the measures proved to be practically ineffective. It is concluded that the effectiveness of regular and moderate intensity physical exercise is age-dependent while the action of E2 treatment is comparable between the ageing and old female rats on maintaining cognition and its underlying molecular mechanisms. PMID:22722983

Marosi, Krisztina; Felszeghy, Klára; Mehra, Raj D; Radák, Zsolt; Nyakas, Csaba



Gavage administration of the fungal toxin fumonisin B1 to female Sprague-Dawley rats.  


The fungal toxin fumonisin B1 (FB1) is a contaminant of corn-based foods and feeds produced by members of the genus Fusarium. Fumonisin B1 toxicity was examined using gavage administration of purified toxin to female Sprague-Dawley rats. For 11 consecutive days each rat received a single dose of FB1 at the following concentrations: control (saline), 1, 5, 15, 35, or 75 mg FB1/kg body weight/d. Significantly depressed body weight and food consumption occurred at 35 and 75 mg FB1/kg/d. By the end of the dosing period there were no significant changes in food consumption. Kidneys and bone marrow were most sensitive to FB1 exposure. Changes in renal morphology were observed from 5 to 75 mg FB1/kg/d, accompanied by transient changes in urine osmolality and urine enzyme levels. Increased cellular vacuolation was the primary change associated with bone-marrow toxicity, starting at doses of 5 mg FB1/kg/d. Hepatotoxicity was indicated by reduced liver weight, elevated serum alanine amonitransferase (ALT), and mild histopathological changes occurring at doses of 15 mg FB1/kg/d and higher. Increased cytoplasmic vacuolation of adrenal cortex cells occurred in rats treated with 15 mg FB1/kg/d and higher, indicating that the adrenals are also potential targets of FB1. Elevated serum cholesterol, which is a consistent response to FB1 was observed at 5 mg FB1/kg/d and higher. Based on responses in this study, gavage is an appropriate substitute for longer feeding studies. Compared to previous work with male rats, gender-related difference in FB1 responses lacked consistency but indicated that males may be marginally more sensitive than female Sprague-Dawley rats. PMID:9444317

Bondy, G S; Suzuki, C A; Mueller, R W; Fernie, S M; Armstrong, C L; Hierlihy, S L; Savard, M E; Barker, M G



Effects of neonatal handling on basal and stress-induced monoamine levels in the male and female rat brain  

Microsoft Academic Search

Neonatal handling has pervasive effects on the rat brain leading to increased ability to cope with and adapt to stressful stimuli. We determined the effects of neonatal handling on the dopaminergic and serotonergic system, in the male and female rat brain, under basal conditions before and after puberty and after short- and long-term forced swimming stress.Exposure of animals to neonatal

A Papaioannou; U Dafni; F Alikaridis; S Bolaris; F Stylianopoulou



Differential effects of the aging process on the morphology of the hypothalamic ventromedial nucleus of male and female rats  

Microsoft Academic Search

We investigated the effects of aging on the neuroanatomical sex dimorphisms of the rat hypothalamic ventromedial nucleus (VMN). Stereological methods were used to estimate the volume of the VMN and the total number and size of its neurons, including their dendritic trees, in males and females aged 6 and 24 months. No cell loss was detected in aged rats. However,

M. Dulce Madeira; Lu??s Ferreira-Silva; Carlos Ruela; Manuel M Paula-Barbosa



Differential Activation of the Periaqueductal Gray by Mild Anxiogenic Stress at Different Stages of the Estrous Cycle in Female Rats  

Microsoft Academic Search

The effect of acute exposure to mild anxiogenic stress on cutaneous nociceptive threshold was investigated in female Wistar rats at different stages of the estrous cycle. Baseline tail flick latencies did not change significantly during the cycle. However after brief exposure to vibration stress (4 Hz for 5 min), rats in late diestrus, but not at other cycle stages, developed

Adam J Devall; Thelma A Lovick



The pheromonal restoration of cyclic activity in young estrogenized persistent estrus female rats is a vomeronasal effect  

Microsoft Academic Search

Eight sham-operated (SO) and six vomeronasalectomized (VMNX) young adult female rats were used to demonstrate the participation of the vomeronasal organ (VNO) in the pheromonal restoration of cyclic activity (PRCA). All rats were normal four-day cycling before and after surgery and they received a single subcutaneous injection of 2 mg of estradiol benzoate (EB) to induce an anovulatory persistent vaginal

O. A. Mora; M. M. Cabrera



Opioid binding in the rostral hypothalamus is reduced following lesion of the ventral noradrenergic tract in female rats  

Microsoft Academic Search

Experiments were undertaken to establish whether opioid receptors exert a direct presynaptic influence on noradrenergic (NA) terminals in the preoptic\\/ anterior hypothalamus (PO\\/AH) of the female rat. Thus, opioid binding studies were performed in rats with lesions of the ventral NA tract (VNAT; the main NA projection to the hypothalamus) to assess whether a loss of NA terminals may also

R. G. Dyer; N. Parvizi; S. Hollingsworth; S. Mansfield; R. P. Heavens; R. J. Bicknell; D. J. S. Sirinathsinghji



Estradiol-mediated increases in the anorexia induced by intraperitoneal injection of bacterial lipopolysaccharide in female rats  

Microsoft Academic Search

Lipopolysaccharide (LPS) derived from the cell walls of gram-negative bacteria causes a robust acute phase response (APR) that includes fever, anorexia, and many other elements. Because immune system function, including some models of illness anorexia, is sexually differentiated, we investigated the sexual differentiation of the anorexia induced by intraperitoneal LPS injections in rats. Cycling female Long–Evans rats tested either during

Nori Geary; Lori Asarian; James Sheahan; Wolfgang Langhans



Gonadal steroids mediate the opposite changes in cocaine-induced locomotion across adolescence in male and female rats  

Microsoft Academic Search

Evidence from both human studies and animal models indicates that cocaine elicits more behavioral stimulation in females than males. The present study sought to determine whether sex-specific responses to cocaine emerge during adolescence and to determine if gonadal steroid action during puberty affects adult responsiveness to cocaine. We administered cocaine using an escalating dose model in male and female rats

Sarah L. Parylak; Joseph M. Caster; Q. David Walker; Cynthia M. Kuhn



Early exposure to a low dose of bisphenol A affects socio-sexual behavior of juvenile female rats  

Microsoft Academic Search

Play behavior is affected by alteration of the hormonal environment during development. In fact, congenital adrenal hyperplasia or early administration of diethylstilbestrol are able to modify female play behavior in mammals. In this research, play behavior of female rats was used to explore the effects of perinatal exposure to low, environmentally relevant dose of bisphenol A (BPA), a xenoestrogen widely

Stefania Porrini; Virginia Belloni; Daniele Della Seta; Francesca Farabollini; Giuletta Giannelli; Francesco Dessì-Fulgheri




EPA Science Inventory

Female rats were dosed by oral gavage from postnatal day (PND) 22 through PND 41 with 0, 12.5, 25, 50, 100 or 200 mg ATR /kg. Half of the females in each treatment group were killed on PND 41 and organ weights (e.g., liver, kidney, adrenal, ovary, uterus and pituitary) and serum ...


Effect of Mimosa pudica root powder on oestrous cycle and ovulation in cycling female albino rat, Rattus norvegicus.  


Mimosa pudica root powder (150 mg/kg body weight) when administered intragastrically, altered the oestrous cycle pattern in female Rattus norvegicus. Nucleated and cornified cells were absent in all rats. The smear was characterized by leucocytes only, as in dioestrus, which persisted for 2 weeks. There was a significant reduction in the number of normal ova in rats treated with the root powder compared with the control rats, and a significant increase in the number of degenerated ova. PMID:11933127

Valsala, S; Karpagaganapathy, P R



Levels of DNA damage in blood leukocyte samples from non-diabetic and diabetic female rats and their fetuses exposed to air or cigarette smoke.  


The objective of the present study was to evaluate DNA damage level in blood leukocytes from diabetic and non-diabetic female Wistar rats exposed to air or to cigarette smoke, and to correlate the findings with levels of DNA damage detected in blood leukocyte samples from their fetuses. A total of 20 rats were distributed into four experimental groups: non-diabetic (control; G1) and diabetic exposed to filtered air (G2); non-diabetic (G3) and diabetic (G4) exposed to cigarette smoke. Rats placed into whole-body exposure chambers were exposed for 30min to filtered air (control) or to tobacco smoke generated from 10 cigarettes, twice a day, for 2 months. Diabetes was induced by a pancreatic beta-cytotoxic agent, streptozotocin (40mg/kgb.w.). At day 21 of pregnancy, each rat was anesthetized and humanely killed to obtain maternal and fetal blood samples for genotoxicity analysis using the alkaline comet assay. G2, G3 and G4 dams presented higher DNA damage values in tail moment and tail length as compared to G1 group. There was a significant positive correlation between DNA damage levels in blood leukocyte samples from G2 and G3 groups (tail moment); G3 and G4 groups (tail length) and G3 group (tail intensity) and their fetuses. Thus, this study showed the association of severe diabetes and tobacco cigarette smoke exposure did not exacerbate levels of maternal and fetal DNA damages related with only diabetes or cigarette smoke exposure. Based on the results obtained and taking into account other published data, maternal diabetes requires rigid clinical control and public health and education campaigns should be increased to encourage individuals, especially pregnant women, to stop smoking. PMID:18455954

Lima, Paula Helena Ortiz; Damasceno, Débora Cristina; Sinzato, Yuri Karen; de Souza, Maricelma da Silva Soares; Salvadori, Daisy Maria Fávero; Calderon, Iracema de Mattos Paranhos; Rudge, Marilza Vieira Cunha



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. Copyright © 2013 John Wiley & Sons, Ltd. PMID:23740556

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



Altered responses to dizocilpine maleate administration in ethanol-withdrawn male and female rats.  


Dizocilpine maleate (MK-801) is a highly potent, noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist. Although it has been suggested that dizocilpine may be beneficial in alleviating some symptoms of ethanol withdrawal, a rigorous evaluation of beneficial versus detrimental (phencyclidine-like) actions has not been done. The objective of the present investigation was to explore whether dizocilpine protects against ethanol withdrawal-induced increases in seizure susceptibility without being compromised by its phencyclidine-like behavioral actions. The effects of dizocilpine were assessed by using seizure threshold determinations and scoring of open field behaviors. Low dose dizocilpine administration preferentially protected against bicuculline seizure induction in ethanol-withdrawn female rats when compared with findings in ethanol-withdrawn male rats. In contrast, we found dramatic reductions in dizocilpine-induced open field behaviors during ethanol withdrawal in both male and female rats compared with findings for pair-fed control animals. [3H]MK-801 binding analysis ruled out changes in cerebral cortex or hippocampus receptor density or affinity as having a primary role in these differential responses. Taken together, our findings from these studies indicate that there are complex neuroadaptations in NMDA receptor systems after persistent ethanol exposure, manifested as either enhanced or reduced responses, depending on the measure used. PMID:12457939

Devaud, Leslie L; Bartoo, Gabriel; Malthankar, Gaurangi



In utero exposure to the environmental androgen trenbolone masculinizes female Sprague-Dawley rats.  


Recently, the occurrence of environmental contaminants with androgenic activity has been described from pulp and paper mill effluents and beef feedlot discharges. A synthetic androgen associated with beef production is trenbolone acetate, which is used to promote growth in cattle. A primary metabolite, 17beta Trenbolone (TB), has been characterized as a potent androgen in both in vitro and in vivo studies with rats. The current study was designed to characterize the permanent morphological and functional consequences of prenatal TB exposure on female rats compared with those produced in an earlier study with testosterone propionate (TP). Female rat offspring were exposed to 0mg/day, 0.1mg/day, 0.5mg/day, 1.0mg/day, or 2.0mg/day TB on gestational days 14-19. The 0.5mg/day, 1.0mg/day, or 2.0mg/day TB groups displayed increases in neonatal anogenital distance (AGD) which persisted in the high dose group. Puberty was delayed in the high dose group and there were increased incidences of external genital malformations and the presence of male prostatic tissue in the 0.5mg/day, 1.0mg/day, or 2.0mg/day groups. These changes were associated with amniotic fluid concentrations of TB that compare favorably with concentrations known to be active in both in vitro systems and in fish. PMID:17931805

Hotchkiss, A K; Furr, J; Makynen, E A; Ankley, G T; Gray, L E



Phytoestrogens Enhance the Vascular Actions of the Endocannabinoid Anandamide in Mesenteric Beds of Female Rats  

PubMed Central

In rat isolated mesenteric beds that were contracted with NA as an in vitro model of the vascular adrenergic hyperactivity that usually precedes the onset of primary hypertension, the oral administration (3 daily doses) of either 10?mg/kg genistein or 20?mg/kg daidzein potentiated the anandamide-induced reduction of contractility to NA in female but not in male rats. Oral treatment with phytoestrogens also restored the vascular effects of anandamide as well as the mesenteric content of calcitonin gene-related peptide (CGRP) that were reduced after ovariectomy. The enhancement of anandamide effects caused by phytoestrogens was prevented by the concomitant administration of the estrogen receptor antagonist fulvestrant (2.5?mg/kg, s.c., 3 daily doses). It is concluded that, in the vasculature of female rats, phytoestrogens produced an estrogen-receptor-dependent enhancement of the anandamide-vascular actions that involves the modulation of CGRP levels and appears to be relevant whenever an adrenergic hyperactivity occurs.

Peroni, Roxana N.; Abramoff, Tamara; Neuman, Isabel; Podesta, Ernesto J.; Adler-Graschinsky, Edda



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.



Agmatine Reduces Ultrasonic Vocalization Deficits in Female Rat Pups Exposed Neonatally to Ethanol  

PubMed Central

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 20 mg/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.

Wellmann, Kristen; Lewis, Ben; Barron, Susan



Dissociation Between the Aversive and Pharmacokinetic Effects of Ethanol in Female Fischer and Lewis Rats  

PubMed Central

In humans and laboratory animal models, vulnerability to alcohol abuse is influenced by endogenous factors such as genotype. Using the inbred Fischer and Lewis rat strains, we previously reported stronger conditioned taste aversions (CTA) in male Fischer rats that could not be predicted by genotypic differences in alcohol absorption [34]. The present study made similar assessments in Fischer and Lewis females via four-trial CTA induced by 1 or 1.5 g/kg intraperitoneal (IP) ethanol (n = 10-12/strain/dose) as well as measures of blood alcohol concentrations (BAC) at 15, 60 and 180 min post-injection with 1.5 g/kg IP ethanol or saline (n = 7-8/strain/dose). Dose-dependent CTAs were produced, but the strains did not differ from each other in these measures; however, BACs in the Lewis females were significantly higher than Fischer at all three time points. As with males of the Fischer and Lewis genotypes, a dissociation between BACs and the aversive effects of alcohol was observed. These data are the first assessments of these particular phenotypes in Fischer and Lewis females, and when considered with the historical data, suggest a Genotype × Sex interaction in the centrally-mediated sensitivity to alcohol's aversive effects.

Roma, Peter G.; Chen, Scott A.; Barr, Christina S.; Riley, Anthony L.



Collaborative work on evaluation of ovarian toxicity. 15) Two- or four-week repeated-dose studies and fertility study of bromocriptine in female rats.  


The main focus of this study is to determine the optimal administration period concerning toxic effects on ovarian morphological changes in a repeated-dose toxicity study. To assess morphological and functional changes induced in the ovary by bromocriptine, the compound was administered to female rats at dose levels of 0, 0.08, 0.4 and 2 mg/kg for the 2- or 4-week repeated-dose toxicity study, and for the female fertility study from 2 weeks prior to mating to day 7 of gestation. In the 2-week repeated-dose toxicity study, increase of ovarian weights was observed at 2 mg/kg. In the 4-week repeated-dose toxicity study, ovarian weights were increased at 0.4 and 2 mg/kg. The number of corpora luteum was increased in the 0.4 and 2 mg/kg groups of the 2- and 4-week repeated-dose toxicity studies by histopathological examination of the ovaries. Bromocriptine did not affect estrous cyclicity in 2- and 4-week repeated dosing. In the female fertility study, although animals in any groups mated successfully, no females in 0.4 and 2 mg/kg groups were pregnant. There were no adverse effects on reproductive performance in the 0.08 mg/kg group. Based on these findings, the histopathological changes in the ovary are considered important parameters for evaluation of drugs including ovarian damage. We conclude that a 2-week administration period is sufficient to detect ovarian toxicity of bromocriptine in a repeated-dose toxicity study. PMID:19265282

Kumazawa, Toshihiko; Nakajima, Atsushi; Ishiguro, Tsukasa; Jiuxin, Zhu; Tanaharu, Takashi; Nishitani, Hiromi; Inoue, Yukiko; Harada, Satoko; Hayasaka, Ikuo; Tagawa, Yoshiaki



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

SciTech Connect

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 0.45 g/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 (20 mg/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. - Highlights: > Carvacrol induced a depressive-like phenotype in rats, depending on ovarian cyclicity. > Carvacrol selectively reduced serotonin content in female rats in proestrus phase. > Carvacrol reduced serotonin levels in areas belonging to the emotional circuit. > Carvacrol reduced plasma estradiol levels only during the proestrus phase.

Trabace, L., E-mail: [Department of Biomedical Sciences, University of Foggia, V. le Luigi Pinto 1, 71121 Foggia (Italy); Zotti, M.; Morgese, M.G.; Tucci, P.; Colaianna, M.; Schiavone, S. [Department of Biomedical Sciences, University of Foggia, V. le Luigi Pinto 1, 71121 Foggia (Italy); Avato, P. [Department of Pharmaco-Chemistry, University of Bari, 'A. Moro', Via Orabona 4, 70125, Bari (Italy); Cuomo, V. [Department of Human Physiology and Pharmacology, Vittorio Erspamer, University of Rome 'La Sapienza', P. le Aldo Moro 5, 00185, Rome (Italy)



Recombinant bovine somatotropin decreases hepatic amino acid catabolism in female rats.  


The effect of recombinant bovine somatotropin (rbST) on hepatic amino acid catabolism in female rats was investigated. Daily injections of rbST for 5 d decreased liver homogenate lysine alpha-ketoglutarate reductase (EC activity (P < 0.05) and liver homogenate lysine oxidation (P < 0.05) approximately 35%. Liver homogenate methionine and valine oxidation were depressed approximately 20 (P = 0.13) and 35% (P < 0.05), respectively. These data show a decrease in hepatic capacity to oxidize amino acids in rats administered rbST. Whether depressed liver amino acid degrading enzyme activity plays a role in amino acid oxidation in vivo remains to be evaluated. PMID:8648440

Blemings, K P; Gahl, M J; Crenshaw, T D; Benevenga, N J



A Detailed Study on the Role of Sex Steroid Milieu in Determining Plasma Leptin Concentrations in Adult Male and Female Rats  

Microsoft Academic Search

We examined the effects of sex steroid milieu on plasma leptin levels in adult male and female rats. Since the body weight is known to influence leptin concentrations, the hormone was measured in rats with a very similar body weight (about 250 g) throughout this study. Plasma leptin levels were significantly higher in female than in male rats. Orchidectomy (ODX)

Hajime Watanobe; Toshihiro Suda