INDUCTION OF OVULATION BY GONADOTROPHINS IN THE INDIAN FIVE-STRIPED PALM SQUIRREL FUNAMBULUS PENNANTI (WROUGHTON)

1967 ◽  
Vol 39 (3) ◽  
pp. 369-NP ◽  
Author(s):  
PUSHPA SETH ◽  
M. R. N. PRASAD
Keyword(s):  
Breeding Season ◽  
Reproductive Cycle ◽  
Single Injection ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Follicular Growth ◽  
Induction Of Ovulation ◽  
Induced Ovulation ◽  
Follicular Maturation ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY Superovulation was induced in palm squirrels by the administration of gonadotrophins. The regimen of treatment effective in inducing ovulation was 60 i.u. pregnant mare serum gonadotrophin (PMS) administered in three doses of 20 i.u. on days 1, 4 and 7, followed by a single injection of 40 i.u. human chorionic gonadotrophin (HCG) on day 14. The same schedule of PMS and HCG administration induced ovulation in mature and immature squirrels both during the breeding season and the period of sexual quiescence. Ovulation did not occur in PMS-treated females if HCG was not administered. The period required for follicular growth before the follicles responded to the ovulatory stimulus of HCG was 13–14 days; the interval for follicular maturation leading to the release of the ovum was approximately 24 hr. Variations in the numbers of ova shed by different groups of females are related to the phase of the reproductive cycle and the age of the squirrels.

Effects of thymulin on spontaneous puberty and gonadotrophin-induced ovulation in prepubertal normal and hypothymic mice

1999 ◽  
Vol 163 (2) ◽  
pp. 255-260 ◽  
Author(s):  
L Hinojosa ◽  
R Chavira ◽  
R Dominguez ◽  
P Rosas
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Vaginal Opening ◽  
Serum Progesterone ◽  
Thymic Hormone ◽  
Induced Ovulation ◽  
Gonadotrophin Secretion ◽  
Age Dependent ◽  
Neuroendocrine Mechanisms ◽  
Pregnant Mare Serum Gonadotrophin

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.

Control of the time of ovulation in sheep

1960 ◽  
Vol 11 (3) ◽  
pp. 389 ◽  
Author(s):  
AWH Braden ◽  
DR Lamond ◽  
HM Radford
Keyword(s):  
Optimal Control ◽  
Breeding Season ◽  
Artificial Insemination ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Treatment Schedule ◽  
Pregnant Mare Serum Gonadotrophin

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.

scholarly journals The effect of H-2 region and genetic background on hormone-induced ovulation rate, puberty, and follicular number in mice

1991 ◽  
Vol 57 (1) ◽  
pp. 41-49 ◽  
Author(s):  
J. L. Spearow ◽  
R. P. Erickson ◽  
T. Edwards ◽  
L. Herbon
Keyword(s):  
Genetic Background ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Ovulation Rate ◽  
Follicular Atresia ◽  
Linked Gene ◽  
Induced Ovulation ◽  
Follicular Maturation ◽  
Timing Of Puberty

SummaryWe have examined the effects of major histocompatibility (H-2) haplotypes and genetic background (all loci other than the H-2 region) on hormone-induced ovulation rate in congenic strains of mice. In comparison with the H-2a haplotype, the H-2b haplotype increased hormone-induced ovulation rate 92% on the A/J (A) genetic background. However, H-2 haplotype did not affect hormone-induced ovulation rate on the C57BL/10J (C57) genetic background. The H-2b-linked gene(s) increased hormone-induced ovulation rate on the A/J genetic background largely by (1) enhancing the maturation of follicles in response to pregnant mare's serum gonadotrophin (PMSG) and (2) altering the stages of follicular development which can be induced to ovulate in response to human chorionic gonadotrophin (hCG). The observed effects of H-2 on hormone-induced ovulation rate were not explained by differences in the timing of puberty, the number of follicles present in untreated females, or the incidence of follicular atresia. The effect of genetic background on hormone-induced ovulation rate was much greater than was the effect of the H-2 region. We found that hormone-induced ovulation rate was five- to six-fold higher on the C57 genetic background than on the A genetic background. The C57 genetic background increased hormone-induced ovulation rate by (1) enhancing the induction of follicular maturation in response to gonadotropins and (2) by reducing the incidence of follicular atresia.

PROGESTERONE LEVELS AFTER INDUCTION OF OVULATION IN DIOESTROUS RATS

1980 ◽  
Vol 87 (1) ◽  
pp. 141-146 ◽  
Author(s):  
MARIKO SHIROTA ◽  
SHUJI SASAMOTO
Keyword(s):  
Single Injection ◽  
Secretory Activity ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Induction Of Ovulation ◽  
Normal Number ◽  
Lh Rh ◽  
Lh Releasing Hormone ◽  
Premature Ovulation

Maximal levels of progesterone in the plasma after premature ovulation induced by either the administration of human chorionic gonadotrophin (HCG) or LH-releasing hormone (LH-RH) to dioestrous (day 0) rats were observed from 33 to 45 h but decreased 3 h earlier than after spontaneous ovulation. This suggested an earlier decline in the secretory activity of corpora lutea formed from premature ovulations than that of corpora lutea formed during a normal oestrous cycle. The next spontaneous ovulation occurred 4 days (day 5) after premature ovulation induced by LH-RH on day 0. A single s.c. injection of 2·5 μg oestradiol-17β (OE2) at 10.00 h on day 2 to these animals advanced the next spontaneous ovulation by 1 day. A normal number of oocytes was shed, indicating that earlier secretion of oestrogen on day 2 had advanced the next spontaneous ovulation. A single injection of 2·5 μg OE2 to normal 4-day cyclic rats at metoestrus failed to advance the next ovulation. An earlier decline of progesterone levels in the plasma of rats after premature ovulation as compared with spontaneous ovulation may explain the greater effectiveness of oestrogen in the former group. The progesterone surge was observed during the period of premature ovulation in both HCG- and LH-RH-treated groups. This progesterone release in the periovulatory period may be responsible for the inhibition of gonadotrophin surges on the expected day of prooestrus (day 1).

GONADOTROPHIN REQUIREMENTS FOR IMPLANTATION IN THE MOUSE

1971 ◽  
Vol 50 (1) ◽  
pp. 19-27 ◽  
Author(s):  
B. M. BINDON
Keyword(s):  
Luteinizing Hormone ◽  
Half Life ◽  
Single Injection ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Suckling Mice ◽  
Rat Pituitary ◽  
Pituitary Glands ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY Gonadotrophins were injected into mated hypophysectomized and suckling mice in an attempt to induce implantation. In these two classes of animal implantation is normally delayed by absence or suppression of pituitary gonadotrophin release. Antibodies raised against ovine gonadotrophins were injected into mice soon after mating in an attempt to inhibit implantation. Pregnant mare serum gonadotrophin (PMSG) was effective in inducing implantation in both hypophysectomized and in suckling mice. This may mean that a gonadotrophin with the qualities of PMSG normally initiates implantation. Alternatively, PMSG may have been effective by virtue of its long half-life rather than any special hormonal attributes. Human chorionic gonadotrophin was ineffective in both types of mouse. Mixtures of ovine follicle-stimulating hormone (FSH) and luteinizing hormone (LH) (100 μg of each), injected daily for 3 days, were necessary to induce implantation in hypophysectomized mice. Implantation was readily induced in suckling mice by a single injection of FSH (equivalent to 12·5 μg NIH-FSH-S3) prepared from rat pituitary glands. Implantation was readily inhibited by anti-ovine LH. Anti-ovine FSH was ineffective but this did not cross-react with mouse FSH.

Relationship between Changes in Volume of the Oviductal Fluid in the Ampulla and the Descent of Ovulated Eggs from the Ampulla to the Isthmus in Mice

2000 ◽  
Vol 28 (1) ◽  
pp. 20-23 ◽  
Author(s):  
K Kanayama ◽  
H Osada
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Fluid Volume ◽  
Follicular Growth ◽  
Oviductal Fluid ◽  
Pregnant Mare Serum Gonadotrophin

Follicular growth and ovulation were induced in mice by administration of pregnant mare serum gonadotrophin (PMSG) followed 2 days later by human chorionic gonadotrophin; the day of PMSG injection was designated as day 0. The volume of the ampulla was measured and the location of the ovulated eggs determined at 06:00, 10:00, 14:00, 18:00 and 22:00 on day 3, and at 02:00 and 06:00 on day 4. The volume of the ampulla and hence oviductal fluid, peaked at 14:00 on day 3 and then declined. In all oviduct samples taken up to 14:00 on day 3, eggs were found exclusively in the ampulla. Thereafter, an increasing number of eggs were observed in the isthmus. Thus, the migration of eggs from the ampulla to the isthmus was concurrent with the decrease in oviductal fluid volume. The peak in the volume of oviductal fluid seen at day 3 is likely to coincide with the opening of the ampullary-isthmic junction of the oviduct.

THE EFFECT OF A SINGLE INJECTION OF DIETHYLSTILBOESTROL OR PROGESTERONE ON THE HAMSTER OVARY

1965 ◽  
Vol 33 (1) ◽  
pp. 13-23 ◽  
Author(s):  
G. S. GREENWALD
Keyword(s):  
Anterior Pituitary ◽  
Single Injection ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
The Other ◽  
Follicular Atresia ◽  
Follicular Growth ◽  
Antral Follicles

SUMMARY A single injection of 0·25 mg. stilboestrol or 5 mg. progesterone at metoestrus (day 1) affected follicular development in the hamster ovary in different ways. Stilboestrol induced widespread follicular atresia but apparently did not interfere with the release of ovulating hormone at the end of the oestrous cycle. The atresia produced by stilboestrol appears to be mediated by changes in the levels of circulating gonadotrophin rather than by a direct effect on the ovary. This was demonstrated by injecting pregnant mare serum on day 1 of the cycle followed by stilboestrol treatment at various times thereafter. Under these circumstances the ovulation rate was only reduced below control values when stilboestrol was injected on day 1. Progesterone given on day 1 of the cycle did not interfere with the maturation of healthy Graafian follicles but acted on the terminal stages of follicular growth by blocking ovulation. After a single injection of progesterone, the life span of antral follicles was prolonged to 8–9 days. The ovulation-inhibiting effects of progesterone given on day 1 of the cycle were overcome by the injection of human chorionic gonadotrophin on day 4. Thus, progesterone blocked ovulation indirectly by preventing release of ovulating hormone from the anterior pituitary. The effects of shifting the single injection of stilboestrol or progesterone to the other days of the oestrous cycle are also considered.

PROLONGED ACTIVITY IN VIVO OF RABBIT ANTISERA TO PLACENTAL GONADOTROPHINS

1970 ◽  
Vol 46 (2) ◽  
pp. 221-227 ◽  
Author(s):  
B. M. BINDON
Keyword(s):  
Half Life ◽  
Single Injection ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Mouse Uterus ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY Antisera were raised to pregnant mare serum gonadotrophin (PMSG) and human chorionic gonadotrophin (HCG) in male rabbits. The biological potencies of the antisera, A-PMSG and A-HCG, were determined against homologous antigens PMSG and HCG, using the mouse uterus test in immature mice. A single injection of A-PMSG was shown to inhibit the response to PMSG when injected as late as 21 days after the antiserum. The duration of inhibition was shown to depend on the dose of antiserum injected. These results were confirmed in hypophysectomized mice. A-HCG was shown to cause similar prolonged inhibition of the response to HCG in intact mice. The results suggest that A-PMSG and A-HCG persist in the circulation of the mouse for periods of time expected on the basis of the known half-life of rabbit γ-globulin (5 days).

Co-operation of progesterone and prostaglandins in ovulation induced by human chorionic gonadotrophin in immature rats primed with pregnant mare serum gonadotrophin

1983 ◽  
Vol 96 (3) ◽  
pp. 387-393 ◽  
Author(s):  
Heigo Kohda ◽  
Takahide Mori ◽  
Toshio Nishimura ◽  
Akira Kambegawa
Keyword(s):  
Inhibitory Action ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Temporary Increase ◽  
Inhibitory Effects ◽  
Concurrent Administration ◽  
Simultaneous Injection ◽  
Induced Ovulation ◽  
Immature Rats ◽  
Pregnant Mare Serum Gonadotrophin

Serial injections of a mixture of prostaglandin (PG) E2 and F2α 0, 2, 4, and 6 h after simultaneous injection of human chorionic gonadotrophin (hCG) and indomethacin incompletely restored the ovulation that would have been blocked by indomethacin in immature rats treated with pregnant mare serum gonadotrophin followed by hCG. Serial injections of another mixture of PGE2 and PGF2α 6, 8, 10 and 12 h after simultaneous injection of hCG and indomethacin similarly reversed, in part, the inhibitory effects of indomethacin on hCG-induced ovulation. In contrast, serial injections of the mixtures of PGE2 and PGF2α 0, 2, 4, 6, 8, 10 and 12 h after simultaneous injection of hCG and indomethacin completely restored the indomethacin-blocked ovulation, suggesting that the prostaglandins mediate the action of hCG on ovulation both in the earlier and later stages of the preovulatory process. Six hours after simultaneous injection of hCG and indomethacin serial injections of a mixture of PGE2 and PGF2α reproduced the acute and temporary increase in concentrations of progesterone and testosterone in plasma which would have been abolished by indomethacin. Progesterone given concurrently with hCG and indomethacin partially antagonized the inhibitory action of indomethacin on ovulation. Serial injections of a' mixture of PGE2 and PGF2α 6, 8, 10 and 12 h after concurrent administration of progesterone with hCG and indomethacin completely restored the indomethacin-blocked ovulation, suggesting that progesterone can substitute the action of prostaglandins injected serially in the first half of the preovulatory process. It was concluded that the co-operation of progesterone in the earlier stage and of prostaglandins in the later stage of the preovulatory interval is required to mediate the action of hCG on ovulation.

Sign in / Sign up

Export Citation Format

Share Document