INHIBITION OF HUMAN CHORIONIC GONADOTROPHIN-INDUCED HYPERTROPHY OF THE OVARIES AND UTERUS IN IMMATURE MICE BY SOME PINEAL INDOLES, 6-HYDROXYMELATONIN AND ARGININE VASOTOCIN

1976 ◽  
Vol 68 (3) ◽  
pp. 397-400 ◽  
Author(s):  
MARY K. VAUGHAN ◽  
G. M. VAUGHAN ◽  
R. J. REITER
Keyword(s):  
Acetic Acid ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Arginine Vasotocin ◽  
Immature Female ◽  
Female Mice ◽  
Pineal Indoles ◽  
The Absolute

SUMMARY Administration of the indoles 5-methoxytryptophol, 6-hydroxymelatonin, melatonin, N-acetylserotonin or 5-methoxyindole-3-acetic acid (six 100-μg injections given at intervals of 12 h) inhibited both the absolute and relative ovarian and uterine weights of immature female mice pre-treated with HCG. Administration of 5-hydroxytryptophol or 5-methoxytryptamine at the same dosage inhibited ovarian but not uterine hypertrophy in mice pre-treated with HCG.

Prolactin effects on basal and gonadotrophin-stimulated progesterone accumulation by PMSG-primed mouse ovaries in vitro

1985 ◽  
Vol 110 (4) ◽  
pp. 553-557 ◽  
Author(s):  
Julie A. Jonassen ◽  
Alan S. McNeilly
Keyword(s):  
Incubation Period ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Immature Female ◽  
Female Mice ◽  
Follicular Maturation ◽  
Progesterone Secretion ◽  
Ovulatory Follicles ◽  
Primed Mouse

Abstract. To examine the effects of prolactin (Prl) and human chorionic gonadotrophin (hCG) on progesterone production by murine ovarian explants, immature female mice were injected with 4 IU pregnant mare's serum gonadotrophin (PMSG) to induce follicular maturation. After 24 or 40 h mice were killed, ovaries removed, cut into fragments and maintained as explants for 24 h in the presence or absence of ovine or human Prl (25–2500 ng/ml). None of these doses of Prl affected basal progesterone accumulation into media over 24 h. To determine if Prl could modify the capacity of ovarian explants to respond to gonadotrophin, ovaries were incubated with 25 IU/ml hCG for 3 h after an initial 24 h incubation period with or without Prl. Prl had no effect on basal progesterone accumulation but significantly enhanced hCG-stimulated progesterone accumulation during the 3 h incubation period. We conclude that Prl does not inhibit but may enhance progesterone secretion by pre-ovulatory follicles in the mouse.

GONADOTROPHIC RESPONSE OF THE OVARIES OF THE ALBINO MOUSE FOLLOWING CHRONIC LOW-INTENSITY GAMMA IRRADIATION

1963 ◽  
Vol 27 (1) ◽  
pp. 77-86 ◽  
Author(s):  
J. D. HUNTER ◽  
GEORGE M. KRISE
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Immature Female ◽  
Ovarian Weight ◽  
Mature Adults ◽  
Low Intensity ◽  
Early Maturing ◽  
Ovarian Size ◽  
Normal Increase ◽  
Sexually Mature

SUMMARY Immature female albino mice were exposed to 60Co irradiation at rates of 20 r. and 40 r./day to total doses of 250,500,750 and 1000 r. Those irradiated at 40 r./day during the 1st week of life showed only one-third of the normal increase in uterine and ovarian weight after injection of human chorionic gonadotrophin (HCG) when 25 days old. No further decline in response was seen when the total dose was increased from 250 to 1000 r. Irradiation at 20 r./day to total doses of 500 r. produced little change in normal HCG response. In contrast, sexually mature adults exposed at 40 r./day to total doses of 1000 r. showed little response to HCG. Histological examination of ovaries from immature mice exposed to doses of 250, 500 and 1000 r. at 40 r./day revealed a depopulation of primary oocytes and early maturing follicles as well as a notable decrease in ovarian size.

FOLLICLE STIMULATING HORMONE-LIKE ACTIVITY IN HUMAN CHORIONIC GONADOTROPHIN PREPARATIONS

1969 ◽  
Vol 60 (1) ◽  
pp. 137-156 ◽  
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.

THE EFFECT OF CHLORMADINONE ON THE RESPONSE OF THE OVARIES AND UTERUS OF THE IMMATURE RAT TO GONADOTROPHIC STIMULATION

1964 ◽  
Vol 30 (2) ◽  
pp. 235-245 ◽  
Author(s):  
M. J. K. HARPER
Keyword(s):  
Ovarian Response ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
Corpora Lutea ◽  
Immature Female ◽  
Immature Rat ◽  
Orally Active ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Intact Rats

SUMMARY The effects of chlormadinone (6-chloro-Δ6-17α-acetoxyprogesterone), an orally active progestational agent without significant oestrogenic activity, on the response of the ovaries of intact and hypophysectomized immature female rats to exogenous gonadotrophin have been examined. Administration of the steroid whether starting on the same day as, or 4 days before treatment with gonadotrophin, did not depress the ovarian response in intact rats. In hypophysectomized animals, pretreated with the progestagen, the ovarian response to gonadotrophin was depressed. In intact rats, treatment with the steroid and pregnant mare serum gonadotrophin (PMSG) resulted in ovulation, whereas in similar animals given PMSG alone no corpora lutea were found. Corpora lutea were seen in all groups given PMSG and human chorionic gonadotrophin (HCG) but ovulation occurred earlier when, in addition, treatment with the steroid was included. In only one experiment with intact rats did administration of the steroid alone cause a significant increase in uterine weight compared with controls. In neither experiment on hypophysectomized animals did such an increase occur, and significant decreases were recorded.

Precocious ovulation induced by human chorionic gonadotrophin in the immature female rat: comparison of follicle growth induced by treatment with human chorionic gonadotrophin and by electrical stimulation of the hypothalamus

1985 ◽  
Vol 106 (1) ◽  
pp. 61-66 ◽  
Author(s):  
H. M. A. Meijs-Roelofs ◽  
P. Kramer ◽  
P. Osman
Keyword(s):  
Electrical Stimulation ◽  
Ovarian Follicle ◽  
Treated Group ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
Female Rat ◽  
Follicle Growth ◽  
Immature Female ◽  
Stimulation Of

ABSTRACT Precocious first ovulation, preceded by an endogenous preovulatory LH surge, could be predictably induced in immature female rats by administering repeated injections of human chorionic gonadotrophin (hCG). Administration of a dose of 0·05–0·075 i.u. hCG, four times a day from day 28 to day 31 of age resulted in a highly constant ovulatory response: at 4·0±0·0 days after the start of treatment 7·7±0·3 (n = 15) ova were found. Use of a higher dose of hCG (0·1 i.u.) resulted in lower numbers of ova (5·6±0·4, n = 7; P<0·005) whereas use of a lower dose of hCG (0·025–0·038 i.u.) resulted in a less constant timing of the induced ovulation at 5·4±0·2 days after the start of treatment (n = 7; P<0·0005). In animals treated with the dose of 0·05–0·075 i.u. hCG, a positive correlation was found between body weight at the start of treatment and the number of ova released (r = 0·75, n = 25; P<0·001). Ovarian follicle dynamics were studied on the various days of hCG treatment (dose 0·05–0·075 i.u.) and compared with the follicle changes that take place after electrical stimulation of the hypothalamus, performed on day 28, a treatment known to result in first ovulation 4–5 days later. In both groups a decrease in the number of the smallest and the middle-sized antral follicles as compared with their respective controls was seen, whereas numbers of follicles in the largest, 'ovulatable' size classes gradually increased. The pattern was more conspicuous in the hCG-treated group, presumably related to greater constancy in timing of the ovulatory response in this group. The present data support the view that endogenous changes in LH secretion during late prepuberty (which have been found to take place) play a significant role in stimulating late-prepubertal follicle growth and the ensuing first ovulation. J. Endocr. (1985) 106, 61–66

INDUCTION OF SUPEROVULATION AND PREGNANCY IN MATURE MICE BY GONADOTROPHINS

1957 ◽  
Vol 15 (4) ◽  
pp. 374-384 ◽  
Author(s):  
RUTH E. FOWLER ◽  
R. G. EDWARDS
Keyword(s):  
Litter Size ◽  
Mature Female ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
The Other ◽  
Female Mice ◽  
Irregular Distribution ◽  
Natural Mating

SUMMARY 1. The injection of 1 i.u. pregnant mares' serum (PMS) followed after 40 hr by 2 i.u. human chorionic gonadotrophin (HCG), or of 3 i.u. PMS followed by 3 i.u. HCG into mature female mice selected at random with regard to their oestrous cycle induces oestrus and mating in approximately 75%, and ovulation in 99% of them. 2. The induction of superovulation depends on the amount of PMS injected and on the strain of mice used. 3. Two types of egg are ovulated, one being normal and with a cumulus, the other degenerated and without cumulus. 93% of the normal eggs were fertilized and 98% of the pronucleate eggs possessed two pronuclei. 4. Approximately three-quarters of the females which mate in response to the injected gonadotrophins become pregnant, although this number was less than the number becoming pregnant after mating during natural oestrus. Many of the treated females carried their embryos to term and some gave birth to large litters, although resorptions, irregular distribution of embryos in the uterus, and difficulty during parturition occurred in some females. Mean litter size of the treated females was similar to that found after natural mating. 5. After more than one treatment with gonadotrophins, fewer females mated, ovulated, and became pregnant than after the first treatment. This reduction in response may have been due to the greater age of the females or to their decreased sensitivity to the hormones. 6. The value of the method as a technique for inducing oestrus, ovulation, and pregnancy in mature female mice is considered.

OVULATION INDUCED BY PREGNANT MARE SERUM GONADOTROPHIN IN THE IMMATURE RAT TREATED NEONATALLY WITH A LOW OR A HIGH DOSE OF ANDROGEN

1972 ◽  
Vol 55 (3) ◽  
pp. 533-541 ◽  
Author(s):  
J. Th. J. UILENBROEK ◽  
J. J. van der WERFF ten BOSCH
Keyword(s):  
Testosterone Propionate ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
High Dose ◽  
Immature Female ◽  
Immature Rat ◽  
Progesterone Treatment ◽  
Combined Administration ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY Ovulation-inducing effects of pregnant mare serum gonadotrophin (PMSG) were studied in immature female rats treated on day 5 (day 1 = day of birth) with oil or with 5 or 1250 μg testosterone propionate (TP). The response of rats treated with 1250 μg TP was negligible regardless of the age of the animals and of the dose of PMSG. The response of rats treated with 5 μg TP to PMSG alone was low (36% of rats, with 2·6 ova/ovulating rat), but could be improved by progesterone administration 2 days after PMSG injection (91% of rats, with 14·5 ova/ovulating rat). At every age and dose of PMSG tested the response of animals treated with 5 μg TP to combined PMSG and progesterone treatment was less than that of control animals. It is concluded that neonatal TP treatment diminishes the release of endogenous ovulating hormone subsequent to PMSG injection. This effect is dependent on the dose of TP used, but already demonstrable in animals treated with 5 μg TP on day 5, which would have been cyclic and fertile after puberty. Only for the animals treated with 1250 μg TP could a decreased sensitivity of the ovaries to combined administration of PMSG and human chorionic gonadotrophin be demonstrated.

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