ANDROSTANEDIOL SULPHATES IN PERIPHERAL BLOOD OF IMMATURE RATS AND SOME OF THEIR BIOLOGICAL EFFECTS

1976 ◽  
Vol 71 (3) ◽  
pp. 299-304 ◽  
Author(s):  
RIVKA RAVID ◽  
BENJAMIN ECKSTEIN

SUMMARY The conjugation of 5α-androstane-3α,17β-diol (3α-A) and its 3β epimer (3β-A) was determined in the peripheral blood of immature female rats. About two thirds of these steroids were present in blood as sulphates and one third as glucuronides; no free steroids were detected. Administration of 3β-A sulphate (25 μg/100 g body weight/day) and of 3α-A sulphate (50 μg/100 g/day) from day 21 of life until the day of vaginal opening, advanced the day of the first ovulation. Administration of the 3β-A sulphate did not induce precocious vaginal opening whereas the free alcohol was active in this respect. Implantation of 3β-A sulphate, but not of the 3α epimer, into the basal medial hypothalamus resulted in the death of all animals within 24 h.

2010 ◽  
Vol 22 (1) ◽  
pp. 279
Author(s):  
S. H. Hyun ◽  
E. B. Jeung

In this study, to examine the estrogenic activity effects of parabens on hormonal responsiveness and on change in the morphology of reproductive target tissues during a critical development stage in female rats, analyses for parabens including methyl-, ethyl-, propyl-, isopropyl-, butyl-, and isobutylparaben were performed in an immature female Sprague-Dawley rat model. Two hundred female immature rats (n = 10/group) were orally treated with these parabens from postnatal day 21 to 40 in a dose-dependent manner based on our previous study [62.5, 250, and 1000 mg/kg of body weight (BW) per day]. 17α-ethinylestradiol (EE;1 mg/kg of BWper day) was used as a positive control and corn oil as a vehicle.A high doseofmethyl- and isopropylparaben (1000 mg/kg of BW per day) resulted in a significant delay in the date of vaginal opening and a decrease in length of the estrous cycle (P < 0.05). In measurements of organ weight and body weight, we observed significant weight changes in ovaries, adrenal glands, thyroid glands, liver, and kidneys(P < 0.05); conversely, body weight was not altered following paraben treatment. In all groups exposedto paraben treatment, histological analysis of the ovaries from the immature rats revealed interstitial cell disorders, a lack of corpora lutea, an increase in the number of cystic follicles, and thinning of the follicular epithelium, which occurred in a dose-dependent manner. In addition, morphological studies of the uterus revealed the myometrial dysplasia suchas myometrial hyperplasia inthe high-doseofpropyl- and isopropylparaben (1000 mg/kgof BWper day) group and in all dose of butyl- and isobutylparabens groups. We also observed a significant decrease in serum estradiol and T4 concentrations in methyl-, ethyl-, propyl-, isopropyl-, and isobutylparaben-treated groups (P < 0.01 and 0.05).A receptor-binding assay indicated that the relative binding affini- ties of parabens to estrogen receptors occurred in the order: isobutylparaben > butylparaben > isopropylparaben = propylparaben > ethylparaben. These values were much less than the binding affinity for 17?-estradiol. Taken together, long-term exposure to parabens, which show less estrogenic activity than EEl, can produce suppressive effects on hormonal responsiveness and can disrupt the morphology of reproductive target tissues during this critical stage of development in immature female rats.


1982 ◽  
Vol 92 (1) ◽  
pp. 31-35 ◽  
Author(s):  
P. KRAMER ◽  
H. M. A. MEIJS-ROELOFS

The effect was studied of five daily injections of 50 μg of either 5α-androstane-3α,17β-diol (3α-androstanediol) or its 3β-epimer (3β-androstanediol), starting on day 22 of life, on sexual maturation in female rats. No difference was found in the age and body weight at first oestrus between oil-treated rats and rats treated with either 3α- or 3β-androstanediol. The only difference observed between these groups consisted of the occurrence of a 'pinhole' vaginal opening a few days before oestrus in 50% of the steroid-treated rats; in oil-treated rats immediate full vaginal opening and first oestrus coincided in ten out of 12 rats. Different effects were obtained when the higher dose of 100 μg daily was used; effects were dissimilar in rats treated with 3α- and 3β-androstanediol. If administration of the higher dose of 3β-androstanediol was started on day 22 and continued until the day of full vaginal opening and first oestrus, a significant delay of this first oestrus, preceded by a few days of a 'pinhole' type of vaginal opening, was observed. After administration of the higher dose of 3α-androstanediol a 'pinhole' type of vaginal opening, accompanied by dioestrous-like vaginal smears, was also found, but oestrus did not occur during the period when injections were given. After the injections were stopped on day 45, first oestrus developed within 6 days in all rats. The previous findings of others that administration of 3β-androstanediol to the immature female rat may induce precocious puberty (i.e. precocious vaginal opening and first ovulation) were not confirmed in the present study. Our results indicate that high doses of free 3α-androstanediol, and to a lesser degree 3β-androstanediol, may even delay first ovulation in the rat. A possible interference of 3α-androstanediol with the triggering of the first ovulatory gonadotrophin peaks is discussed.


1964 ◽  
Vol 206 (4) ◽  
pp. 805-810 ◽  
Author(s):  
Raul C. Schiavi

The comparative effect of anterior and posterior hypothalamic lesions on the development of sexual maturation of prepubertal female rats was investigated. Lesions by electrocoagulation were made in the medial hypothalamus of 45 rats at 25–26 days of age. Thirty-nine animals of the same age constituted the sham-operated and nonoperated controls. A hastened appearance of vaginal opening and first estrus, a significant increase in uterine weight, precocious ovarian luteinization, and premature sexual cycles were observed following both types of lesions. Sham-operated rats and animals with lesions in other parts of the brain did not show evidence of precocious sexual maturation.


1971 ◽  
Vol 50 (4) ◽  
pp. 679-683 ◽  
Author(s):  
R. COLLU ◽  
F. FRASCHINI ◽  
L. MARTINI

SUMMARY Melatonin and 5-methoxytryptophol, the two methoxyindoles of pineal origin, were injected into a lateral ventricle of the brain of immature female rats. Treatment was started on the 25th day of age and terminated when the vagina opened. The injection of both methoxyindoles resulted in a statistically significant delay in vaginal opening. Since previous experiments had shown that melatonin specifically inhibits secretion of luteinizing hormone and that 5-methoxytryptophol specifically blocks release of follicle-stimulating hormone, the present results support the hypothesis that the onset of sexual maturation needs a balanced secretion of both gonadotrophins.


1970 ◽  
Vol 63 (3) ◽  
pp. 454-475 ◽  
Author(s):  
P. Petrusz ◽  
C. Robyn ◽  
E. Diczfalusy

ABSTRACT The biological effects of human follicle stimulating hormone (FSH) preparations were studied in intact immature female mice and in hypophysectomized immature female and male rats, following the complete neutralization of the luteinizing hormone (LH) content of human urinary menopausal gonadotrophin (HMG) preparations having – prior to neutralization – FSH:LH ratios ranging between 1.0 and 500.0. Neutralization of LH was achieved by the addition of rabbit anti-human chorionic gonadotrophin (HCG) sera of known anti-LH potency. The amount of anti-LH employed was 1.5 to 730 times more than that required for 100% neutralization. In intact immature female mice, such »LH-free« FSH preparations induced an increased ovarian weight, follicle stimulation, as well as a uterine weight increase. In immature hypophysectomized female rats, »LH-free« FSH preparations induced ovarian weight increase, growth and maturation of the Graafian follicles without repair of the deficient interstitial cells and without any signs of luteinization. These ovarian changes were associated with an increase in uterine weight and with vaginal cornification. In view of these data, it is concluded that human urinary FSH per se is capable of inducing oestrogen synthesis in hypophysectomized female rats. In immature hypophysectomized male rats, »LH-free« FSH preparations induced testicular enlargement without any stimulation of the testicular interstitial cells and without any growth of the ventral prostate and seminal vesicles. The same effects were obtained following a prolonged administration (3 weeks); spermiogenesis was stimulated, but no mature spermatozoa were found.


1954 ◽  
Vol 11 (4) ◽  
pp. 359-376 ◽  
Author(s):  
ANITA M. MANDL

SUMMARY The sensitivity of adrenalectomized, control-operated and unoperated rats to pregnant mare serum (PMS) and chorionic gonadotrophin (CG) has been studied. A total of 638 mature and immature female rats was used. The ovaries of adrenalectomized rats were found to contain fewer large follicles and corpora lutea than those of control-operated litter-mates, and the slight ovarian hypertrophy which occurs after surgical trauma was found to be due to an increase in the number of Graafian follicles and corpora lutea. Further experiment showed that, as judged by the weight of the ovaries, adrenalectomy reduces the ovarian reaction to injected PMS (10 i.u./day) in both adult and immature rats. Replacement therapy with DCA (1 mg/day) failed to re-establish the normal response in adults. Treatment with cortisone (1 mg/day) restored the normal reaction in both adult and immature adrenalectomized rats. Adrenalectomized adult rats responded to injected CG (10 i.u./day) as vigorously as their operated and unoperated litter-mates. On the other hand, immature adrenalectomized animals did not respond fully to CG. Treatment with cortisone again fully restored the normal reaction.


1977 ◽  
Vol 75 (3) ◽  
pp. 419-426 ◽  
Author(s):  
H. M. A. MEIJS-ROELOFS ◽  
P. KRAMER

The involvement of the adrenal gland in the release of gonadotrophins and the onset of puberty in female rats was studied. Two and four days after adrenalectomy (ADX) on either day 5 or 10 after birth, a significant decrease in the concentration of FSH was found; 4 days after ADX on either day 15 or 20, FSH concentrations had increased significantly compared with sham-operated and/or intact controls. However, in the rats adrenalectomized on day 15 or 20, the body weights were lower than in control rats. Relative uterine weights (mg/100 g body wt) in adrenalectomized rats never differed from those of control rats. A delay in the time at which vaginal opening and the first oestrus occurred was found in rats adrenalectomized at 20 or 25 days of age; however this delay was accompanied in these rats by a retardation in the gain in body weight. It is argued that the effects of ADX on both the release of gonadotrophins and the onset of puberty are primarily, and presumably exclusively, due to the effects on general bodily development (expressed in body weight). The lack of effect of ADX on uterine weight supports the hypothesis that 'oestrogen-like' products from the adrenal gland are not biologically active as oestrogens.


1978 ◽  
Vol 89 (3) ◽  
pp. 590-598 ◽  
Author(s):  
Marie C. Gelato ◽  
J. Meites ◽  
W. Wuttke

ABSTRACT Female Sprague-Dawley derived rats were either sham-operated or adrenalectomized at 20 days of age. Treatment of separate groups of rats with progesterone, corticosterone or prolactin was started at 21 days of age, and was continued until the day of vaginal opening. Similarly treated rats were decapitated at 25, 29 and 33 days of age and at the day of vaginal opening and the sera were collected from each animal and assayed for prolactin, LH and FSH. All rats were decapitated between 4–6 p. m. Adrenalectomy, as previously reported, significantly delayed the day of vaginal opening. Prolactin treatment advanced the day of vaginal opening in intact rats and it restored the day of vaginal opening in adrenalectomized rats to that of intact control rats. Progesterone treatment always delayed the day of vaginal opening in intact rats. It caused an even greater delay in vaginal opening than adrenalectomy alone. Corticosterone treatment, on the other hand, was able to reverse the effect of adrenalectomy but had no effect on vaginal opening in intact rats. In intact rats serum prolactin levels rose steadily until the day of vaginal opening. Adrenalectomized and intact rats treated with progesterone had significantly decreased serum prolactin levels. However, in adrenalectomized corticosterone treated rats serum prolactin levels were significantly increased at all ages measured when compared to the untreated rats. The FSH and LH levels showed no significant changes during any of these experimental procedures. Approximately 50 % of the rats showed LH peaks on the day of vaginal opening as well as an increase in FSH. The data indicate a prolactin-adrenal interaction for the timing of the onset of puberty in immature rats, assuming that the day of vaginal opening in association with increased gonadotrophin levels is an indicator for the occurrence of puberty.


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.


2009 ◽  
Vol 21 (1) ◽  
pp. 192
Author(s):  
J.-H. Kim ◽  
K.-C. Choi ◽  
E.-B. Jeung

Calcium-related proteins include transient receptor potential vanilloid (TRPV) 5 and 6, plasma membrane calcium-ATPase 1b (PMCA1b), and calbindin-D9k and -D28k. The TRPV6 is a major calcium channel located in the apical and basolateral membranes of cell and distributed widely in many other organs, especially in the exocrine tissues such as intestine and uterus. TRPV6s are generally regulated by vitamin D, a dietary calcium ion and hormone. In particular, uterine TRPV6 appears to be affected by sex steroid hormones, which are altered according to estrous cycle and pregnancy. In order to discover the effect of sex steroid hormones on the regulation of TRPV6, we examined the expression of TRPV6 mRNA by using RT-PCR and real-time PCR, and protein expression of TRPV6 by immunohistochemistry (IHC) in the uterus, duodenum, and kidney. To evaluate the effect(s) of sex steroid hormones on its uterine, duodenal, and renal regulation, 17β-estradiol [E2; 40 μg kg–1 of body weight (bw)] and/or progesterone (P4; 4 mg kg–1 of bw) or vehicle (n = 6/each group) were subcutaneously injected into Sprague-Dawley immature female rats (14 days old, n = 24 in total) for 3 days. As a result, the treatments of immature rats with E2 or P4 increased TRPV6 mRNA for calcium function or regulation in the uterus of immature rats. To confirm the specificity of E2 or P4 through their receptors, we treated the immature rats (extra n = 24 in total) with an estrogen receptor-antagonist, ICI 182,780 (ICI; 30 μg kg–1 of bw), and/or progesterone receptor antagonist, RU 486 (10 mg kg–1 of bw), at 3 days prior to E2 or P4 injection. Consequently, an increase in TRPV6 mRNA was observed in the following 2 treatments; ICI plus E2/P4 and E2/P4 alone. In IHC, we further observed that the expression of duodenal TRPV6 was increased by E2 or P4 and E2 or P4 plus ICI, while no difference was observed in renal TRPV6 by the treatments of sex steroid hormones. In conclusion, these results indicate that the expressions of uterine and duodenal TRPV6 may be induced by E2 and P4, but its renal expression may not be controlled by these steroids.


Sign in / Sign up

Export Citation Format

Share Document