Effects of hydroxyflutamide on rats treated with a superovulatory dose of pregnant mare serum gonadotropin

1991 ◽  
Vol 69 (2) ◽  
pp. 185-190 ◽  
Author(s):  
Frank H. Yu ◽  
Young W. Yun ◽  
Basil Ho Yuen ◽  
Young S. Moon

Immature female rats treated with superovulatory doses of pregnant mare serum gonadotropin (PMSG) were used to study the effects of the antiandrogen hydroxyflutamide on steroid production, particularly the biologically active androgens, in two experiments. In the first experiment, animals were given either 5 mg hydroxyflutamide or vehicle alone at 30 and 36 h following 40 IU PMSG. Compared with the vehicle group, hydroxyflutamide treatment significantly reduced the percentage of degenerate oocytes recovered from oviducts (p < 0.05). Serum levels of testosterone and androstenedione, and their aromatized product 17β-estradiol, significantly decreased (p < 0.05) in the hydroxyflutamide-treated group; however, nonaromatizable androgen, 5α-dihydrotestosterone, was not affected. In the second experiment, ovaries obtained 48 h after stimulation with 4 or 40 IU PMSG were incubated with and without hydroxyflutamide (10−5 M) and (or) testosterone (10−7 M) to study [4-14C]pregnenolone metabolism to major steroids. In 40 IU stimulated ovaries, hydroxyflutamide significantly decreased the metabolism of pregnenolone to progesterone (p < 0.01) and androstenedione (p < 0.01), while the production of 17β-estradiol increased significantly (p < 0.05); however, pregnenolone conversions to testosterone and 5α-dihydrotestosterone were not affected. Testosterone completely reversed the hydroxyflutamide-induced alteration of pregnenolone metabolism. In contrast, there was no difference in the pregnenolone conversion patterns between untreated and hydroxyflutamide or hydroxyflutamide plus testosterone groups in 4 IU stimulated ovaries. Present results confirm our previous finding that hydroxyflutamide decreases the percentage of abnormal oocytes recovered from superovulating rats and indicates that this hydroxyflutamide effect may be partly mediated by altered ovarian steroidogenesis following inhibition of androgen binding in the ovary.Key words: superovulation, pregnant mare serum gonadotropin, antiandrogen, hydroxyflutamide, androgen.

Zygote ◽  
2020 ◽  
Vol 28 (6) ◽  
pp. 482-488
Author(s):  
Gildas Tetaping Mbemya ◽  
Marie Stéphanie Goka Chekem ◽  
Landry Lienou Lienou ◽  
Njina Nguedia Sylvain ◽  
Jiatsa Nathalie Donfack ◽  
...  

SummaryThe present study evaluated the effect of the aqueous extract from leaves of E. speciosa on some physiological and biochemical parameters of reproduction and the onset of puberty in pregnant mare serum gonadotropin (PMSG)-primed immature female rats. High pressure liquid chromatography (HPLC) was used to quantify the phenolic compounds in the methanol/methylene chloride (1:1) extract, the ethanolic and ethyl acetate fractions and the aqueous residue of E. speciosa. E. speciosa (0, 8, 32 or 64 mg/kg) were administered for 15 days to 24 non-PMSG-primed and 24 primed rats with 0.01 IU of PMSG. At the end of the treatment period, animal were sacrificed and their body, ovarian, uterine weight, ovarian protein or cholesterol level, as well as data on puberty onset were recorded. Of the 16 polyphenolic compounds quantitatively revealed in the extracts and fractions of E. speciosa after HPLC analysis, quercetin, rutin, apigenin and eugenol were the most abundant. Non-primed rats showed a significant increase (P < 0.05) in the uterine relative weight at the dose of 8 mg/kg when compared with the other treatments. The uterine proteins and the ovarian cholesterol (P < 0.05), respectively, showed a reduction at doses of 64 mg/kg and 32 mg/kg in non-primed rats. However in PMSG-primed rats, a significant decrease (P < 0.05) was observed in ovarian cholesterol at 64 mg/kg. In conclusion, E. speciosa potentializes the PMSG-inducing effect on folliculogenesis in PMSG-primed rats.


Author(s):  
T. M. Crisp ◽  
F.R. Denys

The purpose of this paper is to present observations on the fine structure of rat granulosa cell cultures grown in the presence of an adenohypophyseal explant and to correlate the morphology of these cells with progestin secretion. Twenty-six day old immature female rats were given a single injection of 5 IU pregnant mares serum gonadotropin (PMS) in order to obtain ovaries with large vesicular follicles. At 66 hrs. post-PMS administration (estrus indicated by vaginal smear cytology), the ovaries were removed and placed in a petri dish containing medium 199 and 100 U penicillin/streptomycin (P/S)/ml. Under a 20X magnification dissecting microscope, some 5-8 vesicular follicles/ovary were punctured and the granulosa cells were expressed into the surrounding medium. The cells were transferred to centrifuge tubes and spun down at 1000 rpm for 5 mins.


1977 ◽  
Vol 74 (1) ◽  
pp. 99-109 ◽  
Author(s):  
D. DE ZIEGLER ◽  
M. WILKINSON ◽  
DANIELLE CASSARD ◽  
K. B. RUF

An investigation of pituitary sensitivity, assessed in terms of increments in plasma LH and FSH concentrations, to stimulation with one or two injections of gonadotrophin releasing hormone (GnRH) was carried out on 26-day-old immature female rats which had received one of the following priming treatments: 10 μg oestradiol benzoate (OB) as a single injection on day 23 or day 25, or on both days; 10 i.u. pregnant mare serum gonadotrophin (PMSG) on day 24; an electrochemical brain lesion placed in the mediobasal hypothalamus on day 23; control animals received either vehicle alone or a sham lesion. Pituitary sensitivity assessed at 10.00 h on day 26, after one or two injections of GnRH (100 ng/100 g body weight, s.c.), was enhanced to a similar degree in the three groups treated with OB in terms of LH (P < 0-01). The FSH response also increased after OB treatment but was not statistically significant. In contrast, 48 h after the injection of PMSG (i.e. when the rats were in a 'pro-oestrous-like' condition) pituitary sensitivity in terms of both LH and FSH dropped sharply (P < 0·001). In lesioned animals, pituitary sensitivity to one injection of GnRH was unchanged. A second GnRH injection administered after a 60 min interval induced a slightly larger LH response in control animals. In contrast, the ratio of the second response to the first increased in animals treated with PMSG, despite the state of overall decrease in sensitivity, being 4·5:1 in PMSG-treated rats versus 1·4:1 in controls. In a second set of experiments, we investigated the variation of pituitary sensitivity in conjunction with an experimentally induced gonadotrophin surge. In animals treated with OB on day 23 and with 1 mg progesterone at 12·00 h on day 26, pituitary sensitivity was increased at both 14.00 and 17.00 h as compared with that in the day 23 OB-treated group at 10.00 h. The PMSG-treated animals maintained their state of decreased responsiveness at 14.00 h, but exhibited increased pituitary sensitivity at the time of the gonadotrophin surge (17.00 h). These results show that OB increases pituitary sensitivity to GnRH in 26-day-old female rats and that the induction of a gonadotrophin surge further increases this sensitivity. In contrast, PMSG-treated rats displayed a state of decreased responsiveness 48 and 52 h, but not 55 h, after the injection. Pituitary sensitivity on the second day after PMSG treatment thus clearly differs from that observed during pro-oestrus in the adult cyclic female rat.


1981 ◽  
Vol 241 (6) ◽  
pp. E460-E464
Author(s):  
J. R. Lorenzen ◽  
J. A. Ramaley

Serum gonadotropin levels were measured 12, 24, and 48 h after gonadectomy in male and female rats (ages, 22--60 days) to assess when during development the rate of rise of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) after castration approximates that seen in the gonadectomized adult. In females serum LH levels 48 h after ovariectomy were increased above sham levels only when the ovaries were removed prior to vaginal opening. Ovariectomy on the day of vaginal opening or at older ages resulted in no increase in LH levels by 48 h after surgery. Serum FSH levels at 24 and 48 h after ovariectomy declined with increasing age at the time of ovariectomy. In males serum LH levels at 48 h after castration increased with increasing age at the time of gonadectomy. Serum FSH levels at either 12, 24, or 48 h after orchidectomy did not change appreciably with age at the time of surgery. It is concluded that the acute pituitary secretion of gonadotropins after removal of testes in the immature male resembles that seen in the mature male early in the course of the development of sexual maturity. In contrast, the acute pituitary secretion of gonadotropins after removal of the ovaries in the immature female does not resemble that seen in the ovariectomized adult until she is mature and capable of ovulating. Thus, the observed delay in the rise of LH seen in ovariectomized adults may be a function of some aspect of the hormonal changes associated with the estrous cycle.


Endocrinology ◽  
2011 ◽  
Vol 152 (5) ◽  
pp. 1745-1751 ◽  
Author(s):  
Sharon Barouk ◽  
Tana Hintz ◽  
Ping Li ◽  
Aine M. Duffy ◽  
Neil J. MacLusky ◽  
...  

Vascular endothelial growth factor (VEGF) is critical to angiogenesis and vascular permeability. It is also important in the endocrine system, in which VEGF mediates the vascular effects of estrogens in target tissues such as the uterus, a response attributed to an estrogen response element on the VEGF gene. Here we asked whether 17β-estradiol increases VEGF levels in the brain. We focused on the hippocampus, in which 17β-estradiol and VEGF both have important actions, and used immunocytochemistry to evaluate VEGF protein. VEGF immunoreactivity was compared in adult female rats sampled during the estrous cycle when serum levels of 17β-estradiol peak (proestrous morning) as well as when they are low (metestrous morning). In addition, adult rats were ovariectomized and compared after treatment with 17β-estradiol or vehicle. The results demonstrated that VEGF immunoreactivity was increased when serum levels of 17β-estradiol were elevated. Confocal microscopy showed that VEGF immunofluorescence was predominantly nonneuronal, often associated with astrocytes. Glial VEGF labeling was primarily punctate rather than diffuse and labile because glial VEGF immunoreactivity was greatly reduced if tissue sections were left in an aqueous medium overnight. We conclude that VEGF protein in normal female hippocampus is primarily nonneuronal rather than neuronal and suggest that glial VEGF immunoreactivity has been underestimated by past studies with other methods because there is a labile extracellular pool. We suggest that estrogens may exert actions on female hippocampal structure and function by increasing hippocampal VEGF.


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