The effect of pregnant mare serum gonadotrophin and human chorionic gonadotrophin on ovulation and on fertility in the ewe

1970 ◽  
Vol 21 (5) ◽  
pp. 807 ◽  
Author(s):  
ID Killeen ◽  
NW Moore

An experiment involving 300 cyclic Merino ewes and designed to study the effects of pregnant mare serum gonadotrophin (PMSG) and human chorionic gonadotrophin (HCG) on ovulation and subsequent fertility is described. PMSG (750 i.u.) was given on the 12th day of the oestrous cycle and HCG (400 and 800 i.u.) was injected intravenously within 3 hr of the onset of oestrus. PMSG induced multiple ovulation and hastened the time of ovulation in relation to the onset of oestrus by 2-3 hr, but did not enhance the precision of the time of ovulation. HCG had no effect upon the time of ovulation but did increase the proportion of follicles which ruptured. Neither PMSG nor HCG, alone or in combination, adversely affected fertility. In fact, HCG increased the proportion of ewes which lambed. Both PMSG and HCG increased the incidence of multiple births. The effect of PMSG on the incidence of multiple births was a direct reflection of its ability to induce multiple ovulation. HCG given alone, or after PMSG increased the incidence of multiple births but its effect was less marked than that of PMSG, and unlike that of PMSG the effect of HCG did not appear to be solely due to an increase in the number of ovulations.

1995 ◽  
Vol 146 (1) ◽  
pp. 169-176 ◽  
Author(s):  
H Kishi ◽  
K Taya ◽  
G Watanabe ◽  
S Sasamoto

Abstract Plasma and ovarian levels of inhibin were determined by a radioimmunoassay (RIA) at 3-h intervals throughout the 4-day oestrous cycle of hamsters. Plasma concentrations of FSH, LH, progesterone, testosterone and oestradiol-17β were also determined by RIAs. In addition, hamsters were injected at various times with human chorionic gonadotrophin (hCG) to determine the follicular development. The changes in plasma concentrations of FSH after injection of antisera to oestradiol-17β (oestradiol-AS) and inhibin (inhibin-AS) on the morning of day 2 (day 1=day of ovulation) were also determined. Plasma concentrations of inhibin showed a marked increase on the afternoon of day 1, remained at plateau levels until the morning of day 4, then increased abruptly on the afternoon of day 4 when preovulatory LH and FSH surges were initiated. A marked decrease in plasma concentrations of inhibin occurred during the process of ovulation after the preovulatory gonadotrophin surges. An inverse relationship between plasma levels of FSH and inhibin was observed when the secondary surge of FSH was in progress during the periovulatory period. Plasma concentrations of oestradiol-17β showed three increase phases and these changes differed from those of inhibin. Changes in plasma concentrations of oestradiol-17β correlated well with the maturation and regression of large antral follicles. Follicles capable of ovulating following hCG administration were first noted at 2300 h on day 1. The number of follicles capable of ovulating reached a maximum on the morning of day 3 (24·8± 0·6), and decreased by 0500 h on day 4 (15·0 ± 1·1), corresponding to the number of normal spontaneous ovulations. Plasma concentrations of FSH were dramatically increased within 6 h after inhibin-AS, though no increase in FSH levels was observed after oestradiol-AS. These findings suggest that changes in the plasma levels of inhibin during the oestrous cycle provide a precise indicator of follicular recruitment, and that the changes in plasma concentrations of oestradiol-17β are associated with follicular maturation. These findings also suggest that inhibin may play a major role in the inhibition of FSH secretion during the oestrous cycle of the hamster. Journal of Endocrinology (1995) 146, 169–176


1983 ◽  
Vol 103 (3) ◽  
pp. 406-412 ◽  
Author(s):  
Kalle Jääkeläinen ◽  
Seppo Markkanen ◽  
Hannu Rajaniemi

Abstract. The subcellular distribution of 125I-labelled human chorionic gonadotrophin (hCG) in preovulatory rat granulosa cells was studied in vivo. Pregnant mare serum gonadotrophin-pretreated immature female rats received an iv injection of [125I]hCG a few hours before the endogenous preovulatory gonadotrophin surge. The animals were killed at 2 or 6 h after the [125I]hCG injections. Light microscope autoradiographs showed that the mural granulosa cells of large follicles were the most highly labelled cells in the ovaries. Electron microscope autoradiography was used to study the subcellular distribution of radioactivity in the mural granulosa cells. At 2 h 45% of the counted silver grains were associated with the plasma membrane and 10% with the lysosomes, at 6 h the values were 51% and 9%, respectively. The distribution of the observed silver grains was compared with the generated expected source to grain pairs by computerized linear multiple regression analysis. The magnitudes of the regression coefficients revealed that the plasma membrane and the lysosomes were the only specifically 125I-labelled organelles, that a few radioactive molecules were located diffusely over the cytoplasm at 2 h and that the 125I-radioactivity of the nuclei was negligible. The present results suggest that preovulatory rat granulosa cells are in vivo able to internalize into lysosomes [125I]hCG initially bound to LH/hCG receptors of the plasma membrane.


1999 ◽  
Vol 163 (2) ◽  
pp. 255-260 ◽  
Author(s):  
L Hinojosa ◽  
R Chavira ◽  
R Dominguez ◽  
P Rosas

The effects of thymulin administration beginning on days 19 or 24 of age on spontaneous puberty and gonadotrophin-induced ovulation were analysed in female normal and hypothymic mice. In normal and hypothymic mice, the daily administration of thymulin at 24 days of age resulted in a delay in the age of vaginal opening, with an increase in serum progesterone levels. Normal mice treated with 200 ng thymulin beginning on day 19 of age and injected with pregnant mare serum gonadotrophin (PMSG) 24 h later had an increase in ovulation rate, number of ova shed and weight of the ovaries. None of the hypothymic mice treated with thymulin on day 19 and PMSG on day 20 ovulated. PMSG treatment on day 25 induced ovulation in hypothymic mice. When these animals were injected previously with 200 ng thymulin, the number of ova shed by ovulating animals was lower than in PMSG-treated animals. Administration of thymulin and sequential injection of PMSG and human chorionic gonadotrophin 54 h later resulted in an increase in ovulatory response in comparison with those receiving only PMSG. The results suggest that thymulin plays a role in the regulation of spontaneous puberty through its effects on adrenal and ovarian endocrine functions. The increase in the ovarian PMSG response-treated animals, previously given thymulin, showed that this thymic hormone participates in the regulation of gonadotrophin secretion mechanisms and seems to be dose- and age-dependent. In hypothymic mice, neuroendocrine mechanisms regulating puberty are different from those of normal mice.


1980 ◽  
Vol 87 (1) ◽  
pp. 123-129 ◽  
Author(s):  
ALBERT RATNER ◽  
G. K. WEISS ◽  
CAROLYN R. SANBORN

Ovarian tissue from immature rats treated with pregnant mare serum gonadotrophin (PMSG) or PMSG and human chorionic gonadotrophin was incubated in Medium 199. Stimulation of the formation of cyclic AMP in follicular and luteal tissue by terbutaline (10−5 mol/l), a selective β2-agonist, was blocked by butoxamine (10−5 mol/l), a selective β2-antagonist, whereas practolol (10−5 mol/l), a selective β1-antagonist, was ineffective. Propranolol (10−5 mol/l), a non-selective β-antagonist, butoxamine nor practolol affected the increase in cyclic AMP promoted by the addition of 1 μg LH. Stimulation of the production of progesterone in both follicular and luteal tissue by terbutaline was blocked by butoxamine, but not by practolol. These findings indicated that β-adrenergic stimulation of ovarian cyclic AMP and progesterone is mediated by β2-adrenergic receptors.


1978 ◽  
Vol 89 (1) ◽  
pp. 158-165 ◽  
Author(s):  
T. J. Weiss ◽  
P. O. Janson ◽  
K. J. Porter ◽  
R. F. Seamark

ABSTRACT The rate of release of cyclic AMP by sheep ovaries containing a corpus luteum was determined at different stages of the cycle before and up to 60 min after an intra-arterial (ia) injection of 500 IU human chorionic gonadotrophin (hCG). The median cyclic AMP concentration in arterial plasma and of ovarian venous plasma following hCG stimulation was 93.2 and 98.0 pmol/ml, respectively. The ovaries of ewes examined at Days 1 and 2 of the cycle showed no response to hCG, whereas in 2 sheep at Day 3, hCG caused a slight response, and in 13 sheep examined between Days 5–18, hCG caused a marked increase in cAMP release. In 5 of the sheep in which both ovarian veins were cannulated, only the ovary with a corpus luteum responded to hCG with an increased secretion rate of cyclic AMP and progesterone. The results indicate a lack of responsiveness in the newly formed corpus luteum to hCG.


1960 ◽  
Vol XXXIV (II) ◽  
pp. 176-188 ◽  
Author(s):  
A. Hasselblatt ◽  
Ch. Ratabongs

ABSTRACT The effect of pregnant mare serum gonadotrophin (PMS) and human chorionic gonadotrophin (HCG) on the thyroid gland of normal, of gonadectomized and of hypophysectomized infantile rats has been studied. Gonadotrophin treatment stimulated the thyroid of normal and hypophysectomized female rats. A corresponding effect was not observed in gonadectomized female or in normal and gonadectomized male rats. These results show that the gonadotrophic hormones stimulate thyroid function indirectly by increasing the hormonal secretion of the ovaries. An intimate functional relationship between the ovaries and the thyroid gland was thus demonstrated. As the stimulating effect of gonadotrophin treatment was also present in hypophysectomized female rats, it was concluded that the oestrogens act directly on the thyroid gland. Their thyrotrophic action is not mediated by the pituitary gland.


1960 ◽  
Vol 11 (3) ◽  
pp. 389 ◽  
Author(s):  
AWH Braden ◽  
DR Lamond ◽  
HM Radford

Synchronization of ovulation in ewes during the breeding season was achieved by a 14 day course of progesterone injections followed by injections of pregnant mare serum gonadotrophin (PMS) and human chorionic gonadotrophin (HCG). Optimal control was attained when the PMS was given at the time of the last progesterone injection and the HCG 24 hr later. With this treatment most ovulations occurred between 20 and 28 hr after the HCG injection. However, none of the ewes exhibited oestrus at this time. Greater variability in the time of ovulation was found when the progesterone-PMS and PMS-HCG intervals were 0 hr and 48 hr, or 24 hr and 24 hr, and with these treatments about 80 per cent. of the ewes exhibited oestrus just before ovulation. On the 0-48 hr treatment schedule with artificial insemination 3-7½ hr after the HCG injection, 13 of 22 ewes had fertilized eggs or embryos when killed 3 or 35 days later.


1964 ◽  
Vol 46 (2) ◽  
pp. 317-330 ◽  
Author(s):  
Savitri K. Shahani ◽  
Shanta Savur Rao

ABSTRACT Immunological investigations with human chorionic gonadotrophin (HCG) were carried out in order to characterize the antigens of HCG. Attempts were also made to find out whether HCG has antigens common to those of human luteinizing hormone (LH) and human follicle stimulating hormone (FSH) and also to ovine, bovine and porcine LH and pregnant mare serum gonadotrophin (PMSG). The results of the immunoelectrophoretic analysis carried out have indicated that one of the three antigens of HCG seems to be immunochemically similar to the antigen present in human LH. HCG was not observed to have any antigens in common with ovine, bovine and porcine LH and PMSG as revealed by the tests carried out with antiserum to HCG. The combining power and the biological activity of the antigen common to human LH and HCG were not completely destroyed by heating the hormones at 100° C for 30 minutes. These were, however, destroyed by treating the respective hormones with 30 per cent hydrogen peroxide. Haemorrhagic follicles were observed when human FSH was injected into immature mice together with human LH. Such haemorrhagic follicles were also observed in some of the mice injected simultaneously with heated LH or HCG along with human FSH. The significance of these observations are discussed.


1971 ◽  
Vol 68 (1) ◽  
pp. 41-49 ◽  
Author(s):  
R. Welschen ◽  
M. Rutte

ABSTRACT Treatment of the adult rat with pregnant mare serum gonadotrophin (PMS) followed by human chorionic gonadotrophin (HCG) is the standard procedure for inducing superovulation. Experiments were performed on rats with a 5 day cycle to determine why treatment with PMS only does not produce superovulation. In untreated animals all follicles in a range of [2267] 55 × 106 μm3 take part in ovulation. Similarly, in precocious ovulation induced by HCG in otherwise untreated animals, all follicles in this size range produce ovulations. After the injection of 5 IU of PMS into rats during oestrus the number of follicles in the size range of [2267] 55 × 106 μm3 is doubled, but only half of them take part in spontaneous ovulation, which occurs one day earlier than in untreated animals. An additional ovulating stimulus by means of treatment with HCG causes no increase in the number of ovulations. Data from hypophysectomized animals receiving HCG indicate that the ovulatory release of luteinizing hormone (LH) is not subnormal following treatment with 5 IU of PMS. After the administration of 10–35 IU PMS in oestrus, spontaneous ovulation does not occur. Data on hypophysectomized animals receiving HCG indicate that at this dose level of PMS, the ovulatory release of LH is subnormal. Indirect evidence suggests that this is due to high oestrogen levels in the blood, blocking the ovulatory release of LH. After 50–80 IU of PMS spontaneous ovulation of a small number of ova occurs on day 3. The ovulatory release of LH, estimated as in the previous experiments, is not distinctly subnormal. Therefore at this dose level of PMS a diminished responsiveness of the ovaries is responsible for the subnormal number of ovulations.


1989 ◽  
Vol 120 (2) ◽  
pp. 325-330 ◽  
Author(s):  
J. Th. J. Uilenbroek ◽  
P. J. A. Woutersen ◽  
P. D. M. van der Vaart

ABSTRACT Corpora lutea could be identified under the dissection microscope up to 7 days after formation. They were isolated during the oestrous cycle and pseudopregnancy and the progesterone and 20α-OH-progesterone contents were compared with serum values of these steroids. The pattern of progesterone in serum resembled that found in the corpora lutea. However, the pattern of 20α-OH-progesterone concentrations in serum and corpora lutea were different. While 20α-OH-progesterone concentrations in the corpora lutea showed large variations during the cycle, changes in serum concentrations of 20α-OH-progesterone were relatively small. Measurement of hormone concentrations in isolated corpora lutea is therefore a sensitive method for studying corpus luteum activity. To study whether corpora lutea derived after ovulation of immature follicles showed deficient luteal activity, rats at dioestrus (2 days before pro-oestrus) were induced to ovulate by the injection of 10 IU human chorionic gonadotrophin (hCG) and subsequent luteal activity was studied by measuring hormone concentrations in the corpora lutea on day 5 of pseudopregnancy. Concentrations of progesterone, but not of 20α-OH-progesterone, in corpora lutea derived from follicles induced to ovulate at dioestrusday 1 were significantly lower than those in corpora lutea derived from follicles induced to ovulate at prooestrus. This difference was observed not only when pseudopregnancy was induced by cervical stimulation but also when it was induced by implantation of a pituitary gland under the kidney capsule. However, in the latter case, corpora lutea already present on the day of hCG injection also became activated. The present experiments demonstrate that by measuring hormone concentrations in isolated corpora lutea changes in luteal activity can be studied effectively. Moreover, it appears that corpora lutea derived from immature follicles contained less progesterone than those derived from fully mature follicles. Journal of Endocrinology (1989) 120, 325–330


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