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.

Follicular dynamics and secretion of inhibin and oestradiol-17β during the oestrous cycle of the hamster

1995 ◽  
Vol 146 (1) ◽  
pp. 169-176 ◽  
Author(s):  
H Kishi ◽  
K Taya ◽  
G Watanabe ◽  
S Sasamoto
Keyword(s):  
Plasma Levels ◽  
Marked Decrease ◽  
Plasma Concentrations ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Oestrous Cycle ◽  
Antral Follicles ◽  
Follicular Maturation ◽  
Follicular Dynamics

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

INITIATION OF FOLLICULAR MATURATION AND OVULATION AFTER REMOVAL OF THE LITTER FROM THE LACTATING RAT

1980 ◽  
Vol 87 (3) ◽  
pp. 393-400 ◽  
Author(s):  
KAZUYOSHI TAYA ◽  
SHUJI SASAMOTO
Keyword(s):  
Plasma Levels ◽  
Plasma Concentrations ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Moderate Increase ◽  
Normal Cycle ◽  
Antral Follicles ◽  
Follicular Maturation ◽  
Follicular Activity

In order to elucidate the mechanism of the resumption of follicular activity and ovulation in rats, levels of FSH, LH and prolactin in plasma and pituitary gland and ovarian follicular development were quantified after removal of the litter on day 3 of lactation (day of parturition = day 0 of lactation). Such removal resulted in ovulation of 13 oocytes 4 days later, a number comparable with that found in normal cyclic rats. Plasma levels of prolactin were high during lactation but markedly decreased after removal of the litter. Although plasma concentrations of FSH and LH did not change during days 3–7 of lactation, there was an FSH surge between 24 and 30 h after removal of the litter. Plasma concentrations of LH also increased slightly but significantly by 24 h after removal of the litter and this value persisted during the following 2 days. Surges of FSH, LH and prolactin occurred at 17.00 h 3 days after pups were removed. Removal of the litter did not increase pituitary contents of FSH, LH and prolactin and a marked reduction in pituitary levels of FSH and LH, but not of prolactin, occurred at 17 00 h 3 days after removal of the litter. A quantitative study of follicular development indicated that follicles larger than 401 μm in diameter were absent during days 3–7 of lactation. However, the number and size of antral follicles increased by 30 h after removal of the litter, probably due to the increases in plasma levels of FSH and LH, and follicles larger than 601 μm in diameter appeared 3 days after the young were removed. Although ovulation could not be induced by human chorionic gonadotrophin from days 3 to 5 of lactation, its administration 30 h after removal of the litter produced ovulation in all rats by the following morning. These results indicated that a moderate increase in FSH, although below the amounts released at the preovulatory surge, together with basal levels of LH which were within the range observed on the day of dioestrus during the normal cycle were responsible for the initiation of follicular maturation after removal of the litter.

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.

THE EFFECT OF INITIAL AGE ON THE RESPONSE OF THE RAT TO TREATMENT WITH GONADOTROPHINS

1973 ◽  
Vol 72 (2) ◽  
pp. 209-217
Author(s):  
S. F. Lunn ◽  
J. A. Loraine
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Ovulation Rate ◽  
Maximum Response ◽  
Induced Ovulation

ABSTRACT In the rat, the age at which the maximum response to gonadotrophin treatment will occur is dependent on both the parameter being examined and the hormone, or combination of hormones used. Thus, the ovulation rate following treatment with pregnant mares' serum gonadotrophin (PMSG) alone, or in combination with human chorionic gonadotrophin (HCG), is maximal at an earlier age than that observed for HCG alone. From the data presented, it would seem that, for the conditions employed, the optimal age of animals for studies on gonadotrophin-induced ovulation would be approximately thirty days.

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.

Selective release of FSH in lactating rats during the period of follicular atresia induced by the administration of antiserum to LH-releasing hormone

1988 ◽  
Vol 118 (3) ◽  
pp. 455-464 ◽  
Author(s):  
K. Taya ◽  
S. Sasamoto
Keyword(s):  
Gradual Increase ◽  
Plasma Concentrations ◽  
Inhibitory Effect ◽  
Negative Influence ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Follicular Atresia ◽  
Follicular Maturation ◽  
Lh Releasing Hormone ◽  
Venous Plasma

ABSTRACT Passive immunoneutralization of LHRH by injecting a caprine antiserum to LHRH (LHRH-AS) in lactating rats nursing two pups on day 5 of lactation resulted in an immediate decline in concentrations of LH in the plasma during the 24-h study period, followed by a gradual increase to control levels 30 h later. Concentrations of oestradiol-17β and inhibin activity in ovarian venous plasma also decreased abruptly in LHRH-AS treated animals and recovered to control levels 36 h later. These changes were correlated with changes in concentrations of LH in the plasma. On the other hand, plasma concentrations of FSH increased abruptly in the LHRH-AS treated animals within 3 h after injection, but the concentrations declined gradually to control levels 48 h later. The ability of follicles to ovulate in response to human chorionic gonadotrophin (hCG) began to decrease within 6 h after treatment with LHRH-AS, and further decreased until 18 h after injection of LHRH-AS, when hCG induced ovulation (with two oocytes) in only one of five animals. A gradual increase in ovulation rate to control levels was noted by 36 h after injection of LHRH-AS. These results indicate that Graafian follicles present at the time of LHRH-AS injection had become atretic and that a new set of follicles had then begun to mature. Selective release of FSH could not be induced by injection of LHRH-AS in ovariectomized animals. Treatment with inhibin (porcine follicular fluid) suppressed the selective release of FSH, whereas treatment with oestradiol-17β had no inhibitory effect on the selective release of FSH. These findings indicate (1) that tonic secretion of LH is an important factor in normal follicular maturation and maintenance in lactating rats, (2) that selective release of FSH after injection of LHRH-AS is attributed to the removal of a negative influence of inhibin from antral follicles during the period of follicular atresia and (3) that a selective surge of FSH is responsible for initiation of new follicular maturation. J. Endocr. (1988) 118, 455–464

AUGMENTATION BY CHLORMADINONE OF THE UTERINE WEIGHT RESPONSE TO HUMAN CHORIONIC GONADOTROPHIN IN INTACT IMMATURE RATS

1965 ◽  
Vol 33 (3) ◽  
pp. 447-454
Author(s):  
M. J. K. HARPER
Keyword(s):  
Single Injection ◽  
Direct Action ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
Uterine Weight ◽  
Control Value ◽  
Orally Active ◽  
Stimulation Of

SUMMARY Administration of chlormadinone, an orally active progestational agent without significant oestrogenic activity, to intact immature female rats did not affect either ovarian or uterine weight significantly compared with controls. A single injection of human chorionic gonadotrophin (HCG) caused a 73 % increase in uterine weight in 24 hr. over the control value. This dose significantly increased ovarian weight and although it caused some stimulation of follicular development, ovulation during this time did not occur. When animals were treated with chlormadinone for 8 days, and received HCG on the 8th day, uterine weight was 170% greater than in the controls and 56% greater than with HCG alone. The uterine weight produced was similar to that found in animals treated with mestranol, a potent oestrogen, and HCG. In ovariectomized animals HCG did not affect uterine weight, while the small increase produced by chlormadinone was unaltered when HCG also was given. Mechanisms are discussed by which this augmentation of the uterine response to HCG might be produced. It seems most likely that chlormadinone administration causes storage of endogenous gonadotrophin in the pituitary, and that the exogenous gonadotrophin acts as the 'trigger' for the release of stored hormone, probably by a direct action on the hypothalamus.

Ovulation rate in ewes treated with pregnant mares' serum gonadotrophin and luteinizing hormone releasing factor

1976 ◽  
Vol 86 (1) ◽  
pp. 127-129 ◽  
Author(s):  
P. T. McGovern ◽  
J. A. Laing
Keyword(s):  
Luteinizing Hormone ◽  
Domestic Animals ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Ovulation Rate ◽  
Commercial Application ◽  
Established Procedure

Although the administration of pregnant mares' serum gonadotrophin (PMSG) to induce superovulation is a well established procedure (see Anderson, Schultz & Melampny, 1963), the unpredictability of the response to this treatment continues to impose a constraint on the commercial application of egg transfer techniques in the large domestic animals. In sheep, the additional use of human chorionic gonadotrophin (HCG) has been mainly centred on attempts to control the time of ovulation (Ortavant, Thibault & Wintenberger, 1949; Braden, Lamond & Radford, 1960; Dziuk et al. 1964; McGovern, Williams & Hancock, 1969). However, Killeen & Moore (1970) found that the proportion of follicles which rupture was increased in PMSG-treated ewes which had been given HCG at the beginning of oestrus. The purpose of the observations recorded here was to examine the possibility that a further gain in ovulation rate in PMSG-treated sheep might be obtained with the use of luteinizing hormone releasing factor (LHRF). No attempt was made to reproduce physiological levels of the releasing factor and dosage was aimed at achieving a superovulatory effect.

Distribution of 125I-labelled follicle-stimulating hormone and human chorionic gonadotrophin in the gonads of hypogonadal (hpg) mice

1982 ◽  
Vol 93 (2) ◽  
pp. 247-NP ◽  
Author(s):  
H. M. Charlton ◽  
Dilys Parry ◽  
D. M. G. Halpin ◽  
R. Webb
Keyword(s):  
Granulosa Cells ◽  
Follicular Development ◽  
Interstitial Cells ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Testicular Development ◽  
Similar Response ◽  
Thecal Cells ◽  
Lh Rh ◽  
Lh Releasing Hormone

Hypogonadal mice are deficient in LH releasing hormone (LH-RH), the releasing factor for LH and FSH, with a consequent failure of postnatal ovarian and testicular development. After intravenous injection of hypogonadal females with 125I-labelled human chorionic gonadotrophin (hCG), followed by autoradiography of semi-thin (1 μm) slices of the ovary, labelled hCG was found to be associated with interstitial cells and thecal cells with little or no labelling of granulosa cells. Labelled human FSH was associated solely with granulosa cells. Hypogonadal females, implanted for 5 days with a silicone elastomer capsule of oestrogen, showed a similar response to that of normal females with hCG labelling of the granulosa cells of the larger follicles as well as of the thecal cell layer. Furthermore, subcutaneous injection of hypogonadal females with LH-RH (50 ng), 12 times daily for 5 days, increased uterine weight and stimulated ovarian development with some large follicles binding hCG to both thecal and granulosa cells. Therefore stimulation of follicular development may possibly be associated with increased oestradiol concentrations. In the male, after injection of 125I-labelled hCG, silver grains were associated with the interstitial cells alone in both hypogonadal and normal mice. Labelled human FSH was undetectable in semi-thin testicular sections, but the mode of injection (intravenous) may not have allowed enough labelled hormone to reach the testis in order to resolve the question as to whether the hypogonadal or normal testis can bind FSH.

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