scholarly journals EFFECTS OF FLUTAMIDE ON SEX MATURATION AND BEHAVIOR OF OFFSPRING BORN TO FEMALE RATS TREATED DURING LATE PREGNANCY

2004 ◽  
Vol 29 (5) ◽  
pp. 517-534 ◽  
Author(s):  
Kazunori GOTO ◽  
Keiji KOIZUMI ◽  
Hitoshi TAKAORI ◽  
Yoshinobu FUJII ◽  
Yuko FURUYAMA ◽  
...  
Author(s):  
Radhika Nagamangalam Shridharan ◽  
Harshini Krishnagiri ◽  
Vijayakumar Govindaraj ◽  
SitiKantha Sarangi ◽  
Addicam Jagannadha Rao

AbstractThe sexually dimorphic organization in perinatal rat brain is influenced by steroid hormones. Exposure to high levels of estrogen or endocrine-disrupting compounds during perinatal period may perturb this process, resulting in compromised reproductive physiology and behavior as observed in adult In our recent observation neonatal exposure of the female rats to estradiol-17β resulted in down-regulation of


2003 ◽  
Vol 285 (2) ◽  
pp. F295-F302 ◽  
Author(s):  
Mong-Heng Wang ◽  
Jishi Wang ◽  
Hsin-Hsin Chang ◽  
Barbara A. Zand ◽  
Miao Jiang ◽  
...  

20-Hydroxyeicosatetraenoic acid (20-HETE), which promotes renal vasoconstriction, is formed in the rat kidney primarily by cytochrome P-450 (CYP) 4A isoforms (4A1, 4A2, 4A3, 4A8). Nitric oxide (NO) has been shown to bind to the heme moiety of the CYP4A2 protein and to inhibit 20-HETE synthesis in renal arterioles of male rats. However, it is not known whether NO interacts with and affects the activity of CYP4A1 and CYP4A3, the major renal CYP4A isoforms in female rats. Incubation of recombinant CYP4A1 and 4A3 proteins with sodium nitroprusside (SNP) shifted the absorbance at 440 nm, indicating the formation of a ferric-nitrosyl-CYP4A complex. The absorbance for CYP4A3 was about twofold higher than that of CYP4A1. Incubation of SNP or peroxynitrite (PN; 0.01–1 mM) with CYP4A recombinant membranes caused a concentration-dependent inhibition of 20-HETE synthesis, with both chemicals having a greater inhibitory effect on CYP4A3-catalyzed activity. Moreover, incubation of CYP4A1 and 4A3 proteins with PN (1 mM) resulted in nitration of tyrosine residues in both proteins. In addition, PN and SNP inhibited 20-HETE synthesis in renal microvessels from female rats by 65 and 59%, respectively. We previously showed that microvessel CYP4A1/CYP4A3 expression and 20-HETE synthesis are decreased in late pregnancy. Therefore, we investigated whether such a decrease is dependent on NO, the synthesis of which has been shown to increase in late pregnancy. Administration of NG-nitro-l-arginine methyl ester (l-NAME) to pregnant rats for 6 days ( days 15- 20 of pregnancy) caused a significant increase in systolic blood pressure, which was prevented by concurrent treatment with the CYP4A inhibitor 1-aminobenzotriazole (ABT). Urinary NO2/NO3 excretion decreased by 40 and 52% in l-NAME- and l-NAME + ABT-treated groups, respectively. Interestingly, renal microvessel 20-HETE synthesis showed a marked increase following l-NAME treatment, and this increase was diminished with coadministration of ABT. These results demonstrate that NO interacts with CYP4A proteins in a distinct manner and it interferes with renal microvessel 20-HETE synthesis, which may play an important role in the regulation of blood pressure and renal function during pregnancy.


2020 ◽  
Vol 14 ◽  
Author(s):  
Cinta Navarro-Moreno ◽  
Maria Jose Sanchez-Catalan ◽  
Manuela Barneo-Muñoz ◽  
Rafael Goterris-Cerisuelo ◽  
Maria Belles ◽  
...  

Motherhood entails changes in behavior with increased motivation for pups, induced in part by pregnancy hormones acting upon the brain. This work explores whether this alters sensory processing of pup-derived chemosignals. To do so, we analyse the expression of immediate early genes (IEGs) in the vomeronasal organ (VNO; Egr1) and centers of the olfactory and vomeronasal brain pathways (cFos) in virgin and late-pregnant females exposed to pups, as compared to buttons (socially neutral control). In pup-exposed females, we quantified diverse behaviors including pup retrieval, sniffing, pup-directed attack, nest building and time in nest or on nest, as well as time off nest. Pups induce Egr1 expression in the VNO of females, irrespective of their physiological condition, thus suggesting the existence of VNO-detected pup chemosignals. A similar situation is found in the accessory olfactory bulb (AOB) and posteromedial part of the medial bed nucleus of the stria terminalis (BSTMPM). By contrast, in the medial amygdala and posteromedial cortical amygdala (PMCo), responses to pups-vs-buttons are different in virgin and late-pregnant females, thus suggesting altered sensory processing during late pregnancy. The olfactory system also shows changes in sensory processing with pregnancy. In the main olfactory bulbs, as well as the anterior and posterior piriform cortex, buttons activate cFos expression in virgins more than in pregnant females. By contrast, in the anterior and especially posterior piriform cortex, pregnant females show more activation by pups than buttons. Correlation between IEGs expression and behavior suggests the existence of two vomeronasal subsystems: one associated to pup care (with PMCo as its main center) and another related to pup-directed aggression observed in some pregnant females (with the BSTMPM as the main nucleus). Our data also suggest a coactivation of the olfactory and vomeronasal systems during interaction with pups in pregnant females.


2009 ◽  
Vol 3 (3) ◽  
pp. 191-195
Author(s):  
L. K. Trofimova ◽  
I. A. Suvorova ◽  
M. V. Maslova ◽  
A. V. Graf ◽  
A. S. Maklakova ◽  
...  

1990 ◽  
Vol 124 (2) ◽  
pp. 191-198 ◽  
Author(s):  
L. Carlsson ◽  
S. Edén ◽  
J.-O. Jansson

ABSTRACT The plasma GH levels of female rats during late pregnancy were determined using an automatic method for repetitive blood sampling from conscious animals. The plasma GH patterns were analysed by a pulse analysis computer program (PULSAR). The mean plasma GH levels were about twofold higher in pregnant females on days 15, 18 and 22 of gestation than in age-matched non-pregnant females. The basal plasma GH levels were also increased, while there was no change in GH pulse amplitude or frequency. The augmentation of GH release was even more pronounced on day 20 of gestation, with a fourfold increase in mean plasma GH levels compared with those in non-pregnant females. This increase reflected an increase in both basal plasma GH levels and GH pulse amplitude, but there was no increase in pulse frequency. In female rats that delivered on day 22 of gestation, the basal and mean plasma GH levels increased during parturition. Pregnant females consistently responded to multiple i.v. infusions of 1 μg human GH-releasing factor analogue (hGRF(1–29)-NH2) given at 45-min intervals on day 18 of gestation. Both basal and GRF analogue-stimulated plasma GH levels were undetectable after hypophysectomy of pregnant rats. The present study demonstrates an increase in basal plasma GH levels during late pregnancy and a marked increase in both basal plasma GH levels and GH pulse amplitude on day 20 of gestation. Furthermore, hypophysectomy of pregnant rats results in undetectable GH levels, indicating that the high levels of GH during pregnancy are derived from the pituitary. Journal of Endocrinology (1990) 124, 191–198


Author(s):  
Melissa Stadt ◽  
Anita T. Layton

Normal pregnancy is characterized by massive increases in plasma volume and electrolyte retention. Given that the kidneys regulate homeostasis of electrolytes and volume, the organ undergoes major adaptations in morphology, hemodynamics, and transport to achieve the volume and electrolyte retention required in pregnancy. These adaptations are complex, sometimes counterintuitive, and not fully understood. In addition, the demands of the developing fetus and placenta change throughout the pregnancy. For example, during late pregnancy, K+ retention and thus enhanced renal K+ reabsorption is required despite many kaliuretic factors. The goal of this study is to unravel how known adaptive changes along the nephrons contribute to the ability of the kidney to meet volume and electrolyte requirements in mid- and late pregnancy. We developed computational models of solute and water transport in the superficial nephron of the kidney of a rat in mid- and late pregnancy. The mid-pregnant and late-pregnant rat superficial nephron models predict that morphological adaptations and increased activity of the sodium hydrogen exchanger 3 (NHE3) and epithelial sodium channel (ENaC) are essential for enhanced Na+ reabsorption observed during pregnancy. Model simulations showed that for sufficient K+ reabsorption, increased H +-K +-ATPase activity and decreased K+ secretion along the distal segments is required in both mid- and late-pregnancy. Furthermore, certain known sex differences in renal transporter pattern (e.g., the higher NHE3 protein abundance but lower activity in the proximal tubules of virgin female rats compared to male) may serve to better prepare the female for the increased transport demand in pregnancy.


2021 ◽  
Author(s):  
Zahra Shaaban ◽  
Amin Tamadon ◽  
Mohammad Reza Jafarzadeh Shirazi ◽  
Mohammad Javad Zamiri ◽  
Amin Derakhshanfar

Abstract Despite the prevalence of polycystic ovary syndrome (PCOS) among childbearing women and the development of many animal models for this syndrome, information on its etiology is still scarce. Intrauterine hyperandrogenic environment may underlie changes at the levels of hypothalamus, pituitary and ovary organization in female offspring, and PCOS later in life. Letrozole, has been shown to mimic reproductive and metabolic characteristics of PCOS in adult rodent models. Therefore, the aim of this research was to assess the condition in a prenatal letrozole-treated rat model. Twenty-eight female rats from dams receiving letrozole at certain doses during late pregnancy were used in the trial. Pregnant Sprague-Dawley rats (n = 21) received letrozole treatment on days 16–18 gestation at doses 1.25, 1.0, 0.75, 0.5, and 0.25 mg/kg body weight (BW). Prenatal letrozole-treatment delayed parturition time and reduced the litter size in pregnant dams (P < 0.0001). Late puberty onset, irregular ovarian cyclicity, increased anogenital distance (AGD), body weight gain, and serum testosterone concentration and reduced estradiol levels (P < 0.0001) were observed in the female offspring of dams receiving 1.25 and 1 mg/kg BW letrozole. Furthermore, Letrozole at 1.25 and 1 mg/kg BW showed increased Rfrp and decreased Gnrh mRNA expression (P < 0.0001). Letrozole treatment at doses 1 mg/kg BW and lower was not feto-toxic. It was concluded that 1 mg/kg BW letrozole may be suggested for prenatal PCOS induction.


2005 ◽  
Vol 98 (3) ◽  
pp. 1013-1020 ◽  
Author(s):  
Dan O. Debrah ◽  
Kirk P. Conrad ◽  
Lee A. Danielson ◽  
Sanjeev G. Shroff

We previously showed that chronic administration of recombinant human relaxin (rhRLX; 4 μg/h) to conscious female, nonpregnant rats to reach serum levels corresponding to early to midgestation (∼20 ng/ml) increases cardiac output (CO) and global arterial compliance (AC) and decreases systemic vascular resistance (SVR), comparable to changes observed in midterm pregnancy. The goals of this study were to test whether chronic administration of rhRLX (4 μg/h) to conscious male rats will yield similar changes in CO and systemic arterial load and to determine whether higher infusion rates of rhRLX (50 μg/h) administered to nonpregnant female rats yielding serum concentrations corresponding to late pregnancy (∼80 ng/ml) will further modify CO and SVR and global AC comparable to late gestation. CO and systemic arterial load, as quantified by SVR and AC, were obtained by using the same methods as in our previous studies. With respect to baseline, chronic rhRLX administration to male rats over 10 days at 4 μg/h increased both CO (20.5 ± 4.2%) and AC (19.4 ± 6.9%) and reduced SVR (12.7 ± 3.9%). These results were comparable to those elicited by the hormone in nonpregnant female rats. In contrast, neither acute (over 4 h) nor chronic (over 6 days) infusion of the higher dose of rhRLX administered to conscious female rats resulted in significant changes in CO, AC, or SVR from baseline. We conclude that 1) rhRLX increases CO and AC and reduces SVR irrespective of sex, and 2) the rhRLX dose response is biphasic insofar as significant alterations in CO and systemic arterial load fail to occur at high serum concentrations.


2019 ◽  
Vol 22 (7) ◽  
pp. 1178-1186 ◽  
Author(s):  
Felix Naughton ◽  
Luis Reeves Vaz ◽  
Tim Coleman ◽  
Sophie Orton ◽  
Katharine Bowker ◽  
...  

Abstract Background Limited research exists on interest in and use of smoking cessation support in pregnancy and postpartum. Methods A longitudinal cohort of pregnant smokers and recent ex-smokers were recruited in Nottinghamshire, United Kingdom (N = 850). Data were collected at 8–26 weeks gestation, 34–36 weeks gestation, and 3 months postpartum and used as three cross-sectional surveys. Interest and use of cessation support and belief and behavior measures were collected at all waves. Key data were adjusted for nonresponse and analyzed descriptively, and multiple regression was used to identify associations. Results In early and late pregnancy, 44% (95% CI 40% to 48%) and 43% (95% CI 37% to 49%) of smokers, respectively, were interested in cessation support with 33% (95% CI 27% to 39%) interested postpartum. In early pregnancy, 43% of smokers reported discussing cessation with a midwife and, in late pregnancy, 27% did so. Over one-third (38%) did not report discussing quitting with a health professional during pregnancy. Twenty-seven percent of smokers reported using any National Health Service (NHS) cessation support and 12% accessed NHS Stop Smoking Services during pregnancy. Lower quitting confidence (self-efficacy), higher confidence in stopping with support, higher quitting motivation, and higher age were associated with higher interest in support (ps ≤ .001). A recent quit attempt and greater interest in support was associated with speaking to a health professional about quitting and use of NHS cessation support (ps ≤ .001). Conclusions When asked in early or late pregnancy, about half of pregnant smokers were interested in cessation support, though most did not engage. Cessation support should be offered throughout pregnancy and after delivery. Implications There is relatively high interest in cessation support in early and late pregnancy and postpartum among smokers; however, a much smaller proportion of pregnant or postpartum women access any cessation support, highlighting a gap between interest and engagement. Reflecting women’s interest, offers of cessation support should be provided throughout pregnancy and after delivery. Increasing motivation to quit and confidence in quitting with assistance may enhance interest in support, and promoting the discussion of stopping smoking between women and health practitioners may contribute to higher support engagement rates.


2009 ◽  
Vol 3 (1) ◽  
pp. 35-43 ◽  
Author(s):  
V. A. Sashkov ◽  
N. B. Sel’verova ◽  
E. D. Morenkov ◽  
I. V. Ermakova ◽  
T. I. Buraya

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