ANTIBODIES TO ESTRONE-PROTEIN CONJUGATES: II. ENDOCRINOLOGICAL STUDIES

It was demonstrated that (i) antiserum to estrone-17-carbamido-HSA neutralized the 6-hour uterotropic activity of exogenous estrone in immature rats, and (ii) the estrone-17-carbamido-proteins were devoid of estrogenic activity at the 5.0-mg dosage level in immature female rats.

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242 POTENTIAL ESTROGENIC EFFECT(S) OF PARABENS AT THE NEONATAL STAGE OF AN IMMATURE FEMALE RAT MODEL

Reproduction Fertility and Development ◽

10.1071/rdv22n1ab242 ◽

2010 ◽

Vol 22 (1) ◽

pp. 279

Author(s):

S. H. Hyun ◽

E. B. Jeung

Keyword(s):

Body Weight ◽

Rat Model ◽

Estrogenic Activity ◽

Female Rats ◽

Female Rat ◽

Dependent Manner ◽

Methyl Ethyl ◽

Immature Female ◽

Immature Rats ◽

Dose Dependent

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.

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Investigation of the estrogenic activity of Pueraria candollei variety mirifica extract on rats

International Journal of Basic & Clinical Pharmacology ◽

10.18203/2319-2003.ijbcp20194255 ◽

2019 ◽

Vol 8 (10) ◽

pp. 2172

Author(s):

Dao Thi Vui ◽

Nguyen Thu Hang ◽

Nguyen Quoc Huy ◽

Bui Thanh Tung

Keyword(s):

Estrogenic Activity ◽

Reproductive Organs ◽

Mature Female ◽

Female Rats ◽

Ovariectomized Rats ◽

Serum Estradiol ◽

Immature Female ◽

Pueraria Candollei ◽

Immature Rats ◽

Estradiol Concentration

Background: Pueraria candollei variety mirifica (PM) has been widely used as ingredient in many rejuvenating products. In this study, we aimed to assess the estrogenic activity of PM extract grown in Vietnam.Methods: Estrogenic activity of PM extract was estimated on immature female rats by using uterotrophic method to measure the weight of the reproductive organs. Estrogenic activity of PM extract also was investigated in mature female ovariectomized rats by evaluating the vaginal cells growth, reproductive organs weight, serum estradiol concentration.Results: Our results showed that PM extract at doses of 100 mg/kg, 200 mg/kg had increased the reproductive organs weight in immature rats and female ovariectomized rats. In addition, PM extract had increased the serum estradiol concentration and the vaginal cells growth by increasing the percentage of keratinocytes in female ovariectomized rats.Conclusions: Our results showed that PM extract has strong estrogenic activity in rats.

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THE SENSITIVITY OF ADRENALECTOMIZED RATS TO GONADOTROPHINS

Journal of Endocrinology ◽

10.1677/joe.0.0110359 ◽

1954 ◽

Vol 11 (4) ◽

pp. 359-376 ◽

Cited By ~ 13

Author(s):

ANITA M. MANDL

Keyword(s):

Chorionic Gonadotrophin ◽

Female Rats ◽

Corpora Lutea ◽

Surgical Trauma ◽

Normal Reaction ◽

Normal Response ◽

Immature Female ◽

Adult Rats ◽

Immature Rats ◽

Adrenalectomized Rats

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.

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186 DUODENAL AND RENAL TRANSIENT RECEPTOR POTENTIAL VANILLOID 6 APPEAR TO BE DISTINCTLY REGULATED BY SEX STEROID HORMONES, ESTROGEN AND PROGESTERONE, IN IMMATURE FEMALE RATS

Reproduction Fertility and Development ◽

10.1071/rdv21n1ab186 ◽

2009 ◽

Vol 21 (1) ◽

pp. 192

Author(s):

J.-H. Kim ◽

K.-C. Choi ◽

E.-B. Jeung

Keyword(s):

Steroid Hormones ◽

Transient Receptor Potential ◽

Receptor Potential ◽

Sex Steroid Hormones ◽

Female Rats ◽

Sex Steroid ◽

Transient Receptor Potential Vanilloid ◽

Immature Female ◽

Immature Rats ◽

Transient Receptor

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.

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GONADOTROPHIN RELEASE IN VITRO, IN THE PRESENCE AND ABSENCE OF LUTEINIZING HORMONE RELEASING HORMONE, BY PITUITARY GLANDS FROM OVARIECTOMIZED AND SHAM-OPERATED IMMATURE FEMALE RATS OF VARIOUS AGES

Journal of Endocrinology ◽

10.1677/joe.0.0880375 ◽

1981 ◽

Vol 88 (3) ◽

pp. 375-379

Author(s):

J. DULLAART

Keyword(s):

Female Rats ◽

Ovariectomized Rats ◽

Immature Female ◽

Releasing Hormone ◽

Incubation Experiments ◽

Immature Rats ◽

Pituitary Glands ◽

Lh Releasing Hormone

Hemipituitary glands of immature female rats, aged 10, 15, 20, 25, 30 and 35 days and either ovariectomized or sham-operated 5 days earlier, were incubated for 2 h in vitro with or without LH releasing hormone. Concentrations of LH and FSH were determined at the end of the incubations in the incubation media and in the hemipituitary glands, and also in the sera collected at the beginning of the incubation experiments. Results showed that in many instances gonadotrophin release was higher after incubation of glands of ovariectomized rats than with glands of control animals. However, these effects of ovariectomy were much smaller than those observed in vivo and were generally absent in rats of less than 20 days of age. It was concluded that ovariectomy may change the secretory characteristics of the gonadotrophic cells of immature rats but that such changes were largely restricted to immature rats older than 20 days.

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FOLLICLE STIMULATING HORMONE-LIKE ACTIVITY IN HUMAN CHORIONIC GONADOTROPHIN PREPARATIONS

Acta Endocrinologica ◽

10.1530/acta.0.0600137 ◽

1969 ◽

Vol 60 (1) ◽

pp. 137-156 ◽

Cited By ~ 5

Author(s):

C. Robyn ◽

P. Petrusz ◽

E. Diczfalusy

Keyword(s):

Follicle Stimulating Hormone ◽

Chorionic Gonadotrophin ◽

Human Chorionic Gonadotrophin ◽

Female Rats ◽

Immature Female ◽

Ovarian Weight ◽

Wide Range ◽

Immature Rats ◽

Stimulation Of ◽

Stimulating Hormone

ABSTRACT The follicle stimulating hormone (FSH)-like activity of human chorionic gonadotrophin (HCG) preparations was assayed by the method based on the ovarian weight augmentation in intact immature rats. The potencies ranged from 4.8 to 7.4 IU equivalents of FSH per mg. The FSH-like potency of the Second International Standard Preparation of HCG was 8.5 IU per vial. However, when in intact immature rats the ovarian weight response to HCG preparations was compared at a wide range of doses (40 to 51 200 IU) to that obtained with a human menopausal gonadotrophin (HMG) preparation (0.5 to 128 IU of FSH) in the presence of 40 IU of HCG, significant differences were found. The assays conducted in hypophysectomised immature female rats were invalid, because of lack of parallelism. Antisera were prepared by immunising rabbits with HCG and human hypophysial gonadotrophin (HHG) preparations and the antigonadotrophin profiles (HCG-, FSH- and FSH-like neutralising potencies) of these antisera were established by the use of statistically valid bioassay procedures. The anti-HCG and anti-HHG sera neutralised the FSH activity of HMG preparations as well as the FSH-like activity of HCG preparations. However, 3 to 175 times more antiserum was required to neutralise the equivalent of 1.0 IU of FSH-like activity present in HCG than expected on the basis of the anti-FSH potency of the antisera. On the other hand, there was a high degree of correlation between the neutralising potencies of the antisera when tested against the FSH-like activity and the HCG activity of various HCG preparations. When the FSH-like activity of an HCG preparation was quantitatively neutralised with an anti-HCG serum, some 30 per cent of the HCG activity remained unneutralised, as evidenced by repeated bioassays. Although at least 2000 IU of this »FSH-free« HCG was administered to groups of intact as well as hypophysectomised immature female rats, this high dose of HCG did not induce an increase in ovarian weight beyond that elicited by 40 IU of untreated HCG. Histological examination of the ovaries indicated lack of follicle stimulation in the hypophysectomised, but not in the intact immature animals. There was an excessive stimulation of the interstitial cells in both types of animals. The data indicate that the FSH-like activity of HCG preparations is neither due to a contamination by FSH of pituitary origin, nor is it an evenly distributed intrinsic property of the HCG molecules. It is also concluded that the gonadotrophic activity of biologically pure HCG in immature hypophysectomised female rats consists of a specific stimulation of the interstitial cell apparatus. Such HCG preparations do not induce any follicle stimulation, not even when administered in excessive doses.

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

Journal of Endocrinology ◽

10.1677/joe.0.0710299 ◽

1976 ◽

Vol 71 (3) ◽

pp. 299-304 ◽

Cited By ~ 11

Author(s):

RIVKA RAVID ◽

BENJAMIN ECKSTEIN

Keyword(s):

Body Weight ◽

Peripheral Blood ◽

Biological Effects ◽

Female Rats ◽

Vaginal Opening ◽

Free Alcohol ◽

Immature Female ◽

Immature Rats ◽

Medial Hypothalamus

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.

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Effects of pregnant mare serum gonadotrophin and oestradiol benzoate on enzymes associated with xenobiotic metabolism in immature and hypophysectomized female rats

Journal of Endocrinology ◽

10.1677/joe.0.1040315 ◽

1985 ◽

Vol 104 (2) ◽

pp. 315-321 ◽

Cited By ~ 2

Author(s):

M. T. Williams

Keyword(s):

Microsomal Protein ◽

Female Rats ◽

Transferase Activity ◽

Immature Female ◽

Immature Rats ◽

Oestradiol Benzoate ◽

Hypophysectomized Rats ◽

Cytochrome P 450 ◽

Plasma Oestradiol ◽

Pregnant Mare Serum Gonadotrophin

ABSTRACT Treatment of immature (22-day-old) female Sprague–Dawley rats with pregnant mare serum gonadotrophin (PMSG) resulted in a significant increase in hepatic microsomal cytochrome P-450 concentrations when compared with animals treated with 0·9% (w/v) NaCl solution. Cytochrome P-450 concentrations in microsomes from control and PMSG-treated animals were 0·49 ± 0·07 and 0·78 ± 0·18 nmol/mg microsomal protein respectively (mean ± s.d.). When hypophysectomized rats were treated with PMSG no significant difference was observed between saline-treated and PMSG-treated animals (0·84 ± 0·06 vs 0·88± 0·08 nmol/mg microsomal protein). Cytochrome b5 concentration and NADPH–cytochrome c reductase and ferricyanide reductase activities were not significantly affected by PMSG treatment. Similar results were obtained when immature and hypophysectomized rats were treated with oestradiol benzoate. Hepatic glutathione (GSH) S-transferase activity was significantly stimulated over control values when hypophysectomized or immature animals were treated with PMSG, oestradiol benzoate or 3-methyl-cholanthrene. Treatment of animals simultaneously with PMSG or oestradiol benzoate and 3-methyl-cholanthrene resulted in higher transferase activity than did either treatment alone. Oestradiol benzoate or PMSG treatment of immature female rats resulted in an approximate twofold increase in hepatic aryl hydrocarbon hydroxylase (AHH) activity. However, AHH activity in hypophysectomized animals was not significantly increased by PMSG or oestradiol benzoate treatment. It is concluded that PMSG or oestradiol benzoate treatment of immature female rats resulted in increased total cytochrome P-450 concentration and AHH activity in hepatic microsomes. Glutathione S-transferase activity was also stimulated. Neither PMSG nor oestradiol benzoate stimulated cytochrome P-450 levels or AHH activity in hypophysectomized rats. However, GSH S-transferase activity was stimulated similar to that in immature animals. Conceivably, the PMSG effect observed in immature rats may be due to PMSG-stimulated increases in plasma oestradiol concentrations which interact at the hypothalamo-pituitary axis. The ability of oestradiol benzoate to mimic the effects of PMSG and the known action of PMSG to increase plasma oestradiol levels in immature rats would tend to support this hypothesis. The lack of increase in cytochrome P-450 concentrations and AHH activity in hypophysectomized female rats would further support the involvement of the pituitary gland in the response to PMSG rather than a direct effect of PMSG or oestradiol benzoate on the liver. Since GSH S-transferase activity is stimulated in both intact and hypophysectomized rats, this system may be under a different control mechanism. J. Endocr. (1985) 104, 315–321

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Estrogenic and Anti-estrogenic Effects of DDT Administered in the Diet to Immature Female Rats

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y72-141 ◽

1972 ◽

Vol 50 (10) ◽

pp. 971-975 ◽

Cited By ~ 23

Author(s):

John G. Clement ◽

Allan B. Okey

Keyword(s):

Female Rats ◽

Immature Female ◽

Estrogenic Effects ◽

Immature Rats ◽

Uterine Growth ◽

Estradiol 17Β ◽

Stimulation Of

Orally administered o,p′-DDT has estrogenic effects on the uterus of immature rats; stimulation of uterine growth is significant, however, only at doses at or above 1000 p.p.m. o,p′-DDT in the diet. At lower doses (100 p.p.m.) both o,p′-DDT and p,p′-DDT reduce the estrogenic response to injected estradiol-17β, probably by stimulating hepatic degradation of the steroid.

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