STUDIES ON GONADOTROPHIN-INDUCED OVULATION IN THE IMMATURE RAT

1968 ◽  
Vol 41 (2) ◽  
pp. 171-177 ◽  
Author(s):  
E. T. BELL ◽  
S. F. LUNN
Keyword(s):  
Marked Effect ◽  
Cell Mass ◽  
Hormone Treatment ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Maximum Increase ◽  
Immature Rat ◽  
Immature Rats ◽  
Wet Weight ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY The effect of the administration of 25 i.u. human chorionic gonadotrophin (HCG) on the induction of ovulation in intact immature rats treated with 50 i.u. pregnant mare serum gonadotrophin (PMSG) has been studied. After the administration of HCG a marked increase in ovarian wet weight was observed. The maximum increase, which occurred 10 hr. after hormone treatment, was noted 2 hr. before ova were found in the oviducts. The alteration in ovarian wet weight was associated with a fall in percentage solids. However, it appears likely that an increase both in follicular fluid and in cell mass occurred before ovulation. Possible reasons for the absence of any marked effect on uterine wet weight or percentage solids are discussed.

CHANGES IN STEROID CONCENTRATION IN THE OVARIES OF IMMATURE RATS TREATED WITH PREGNANT MARE SERUM GONADOTROPHIN AND HUMAN CHORIONIC GONADOTROPHIN

1977 ◽  
Vol 75 (1) ◽  
pp. 43-48 ◽  
Author(s):  
S. BAUMINGER ◽  
B. ECKSTEIN ◽  
H. R. LINDNER
Keyword(s):  
Dehydrogenase Activity ◽  
Hydroxysteroid Dehydrogenase ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Immature Rat ◽  
Immature Rats ◽  
Rat Ovary ◽  
Pregnant Mare Serum Gonadotrophin

The concentrations of testosterone, progesterone and 20α-hydroxypregn-4-en-3-one (20α-OHP) were measured in the ovaries of immature rats in which ovulation was induced by treatment with pregnant mare serum gonadotrophin (PMSG) and, 48 h later, with human chorionic gonadotrophin (HCG). The concentration of testosterone in the tissue increased significantly 48 h after treatment with PMSG, reached a peak 4 h after the administration of HCG and declined to the basal level 4 h later. Increases in the levels of progesterone and 20α-OHP were observed 4 h after the administration of HCG. Whereas the level of 20α-OHP continued to rise during the subsequent 30 h, progesterone levels declined near the presumed time of ovulation (12 h after administration of HCG). It is concluded that 20α-hydroxysteroid dehydrogenase activity is present in the immature rat ovary before ovulation and that an increase in the production of testosterone in the ovaries of rats treated with PMSG and HCG precedes increased production of progesterone and 20α-OHP in these ovaries.

STIMULATION BY β2-ADRENERGIC RECEPTORS OF THE PRODUCTION OF CYCLIC AMP AND PROGESTERONE IN RAT OVARIAN TISSUE

1980 ◽  
Vol 87 (1) ◽  
pp. 123-129 ◽  
Author(s):  
ALBERT RATNER ◽  
G. K. WEISS ◽  
CAROLYN R. SANBORN
Keyword(s):  
Cyclic Amp ◽  
Adrenergic Receptors ◽  
Ovarian Tissue ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Adrenergic Stimulation ◽  
Immature Rats ◽  
Luteal Tissue ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Stimulation Of

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.

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.

Expression of 17β-hydroxysteroid dehydrogenase in the rat ovary during follicular development and luteinization induced with pregnant mare serum gonadotrophin and human chorionic gonadotrophin

1994 ◽  
Vol 140 (3) ◽  
pp. 409-417 ◽  
Author(s):  
S A Ghersevich ◽  
M H Poutanen ◽  
H J Rajaniemi ◽  
R K Vihko
Keyword(s):  
Granulosa Cells ◽  
Follicular Development ◽  
Hydroxysteroid Dehydrogenase ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Northern Hybridization ◽  
Enzyme Expression ◽  
Immature Rat ◽  
Rat Ovary ◽  
Pregnant Mare Serum Gonadotrophin

Abstract Antibodies against human placental 17β-hydroxysteroid dehydrogenase (17-HSD) and 17-HSD cDNA were used to study the expression of the corresponding enzyme in the immature rat ovary during follicular development and luteinization, which were induced by treating the animals with pregnant mare serum gonadotrophin (PMSG) or with PMSG followed by human chorionic gonadotrophin (hCG). Immuno-blot analysis indicated that the Mr of the 17-HSD expressed in rat granulosa cells was 35 000, as previously shown for the human placental enzyme. In immunohistochemical studies of untreated immature rat ovaries, only the granulosa cells from small antral follicles were stained. One day after PMSG treatment, strong expression of 17-HSD was observed in the granulosa cells of growing Graafian follicles. A marked decrease in enzyme expression was observed in preovulatory follicles on day 2 of PMSG treatment, starting from the basal layers of granulosa cells and progressing toward the luminal cells. No 17-HSD expression was detected in luteinized follicles or corpora lutea 22 h after hCG injection. The stroma and theca cells were negative for 17-HSD staining. In Northern hybridization analyses, two 17-HSD mRNAs were detected (1·4 and 1·7 kb). The strongest expression for both mRNAs was detected after 1 day of PMSG treatment, coinciding with maximal immunostaining of the enzyme protein. Down-regulation of 17-HSD observed by immunohistochemistry was reflected in a similar decrease in mRNA expression and the signals were almost undetectable 22 h after hCG injection. Our data suggest that 17-HSD expression in rat granulosa cells is up-regulated during follicular development and, thereafter, the enzyme expression is down-regulated during luteinization. Journal of Endocrinology (1994) 140, 409–417

A PROGESTERONE-DEPENDENT STEP IN OVULATION INDUCED BY HUMAN CHORIONIC GONADOTROPHIN IN IMMATURE RATS PRIMED WITH PREGNANT MARE SERUM GONADOTROPHIN

1980 ◽  
Vol 87 (1) ◽  
pp. 105-107 ◽  
Author(s):  
HEIGO KOHDA ◽  
TAKAHIDE MORI ◽  
YOJIRO EZAKI ◽  
TOSHIO NISHIMURA ◽  
AKIRA KAMBEGAWA
Keyword(s):  
Experimental System ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Immature Rats ◽  
Ovulatory Process ◽  
Pregnant Mare Serum Gonadotrophin

In immature rats primed with pregnant mare serum gonadotrophin, antiserum to progesterone could prevent or reduce ovulation in response to injected human chorionic gonadotrophin (HCG). To be effective, antiserum treatment had to be within 6 h of gonadotrophin treatment; antiserum given 9 h after HCG was ineffective. Progesterone restored the antiserum blocked ovulation completely or incompletely when administered intravenously within 6 h of treatment with HCG. The first 6 h was shown to be a progesterone-dependent step in the ovulatory process in this experimental system.

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.

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.

EFFECT OF HUMAN CHORIONIC GONADOTROPHIN AND OVINE LUTEINIZING HORMONE ON RAT OVARIAN MACROMOLECULAR METABOLISM

1978 ◽  
Vol 76 (2) ◽  
pp. 283-292 ◽  
Author(s):  
M. S. K. PRASAD ◽  
K. MURALIDHAR ◽  
N. R. MOUDGAL ◽  
P. R. ADIGA
Keyword(s):  
Messenger Rna ◽  
Rna Synthesis ◽  
Hormone Treatment ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Millipore Filter ◽  
Biochemical Basis ◽  
Polyadenylic Acid ◽  
Polyuridylic Acid ◽  
Pregnant Mare Serum Gonadotrophin

Administration of human chorionic gonadotrophin (HCG) or ovine LH to immature rats primed with pregnant mare serum gonadotrophin (PMSG) stimulated the rate of synthesis of polyadenylic acid (poly A)-rich RNA in the ovaries. The rate of total RNA synthesis was not affected significantly by hormone treatment, whereas protein synthesis was enhanced. The increase in the rate of synthesis of poly(A)-rich RNA in the ovaries could be inferred as induction of messenger RNA synthesis after the hormone treatment. The poly(A)-rich nature of the isolated RNA was established by oligo(dT)–cellulose chromatography, binding to Millipore filter disks and hydridization with [3H]polyuridylic acid. The level of cyclic AMP in the ovaries of such rats was also raised after administration of LH, the increase coincided with the increase in the rate of synthesis of poly(A)-rich RNA. The implications of these results are discussed in the light of the biochemical basis of luteinization and the action of LH.

INHIBITION OF OVULATION IN THE GONADOTROPHIN-TREATED IMMATURE RAT BY CHLORPROMAZINE

1964 ◽  
Vol 30 (1) ◽  
pp. 87-95 ◽  
Author(s):  
M. X. ZARROW ◽  
K. BROWN-GRANT
Keyword(s):  
Wistar Rats ◽  
Single Injection ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Assay Method ◽  
Systemic Injection ◽  
Immature Rat ◽  
Higher Doses ◽  
Effect Of Age ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY The effect of age and dose of a single injection of pregnant mare serum gonadotrophin (PMS) on spontaneous ovulation in immature Wistar rats is described. Ovulation could be induced by human chorionic gonadotrophin (HCG) at least 6 days before it occurred when pregnant mare serum gonadotrophin alone was given. Chlorpromazine was shown to block pregnant mare serum gonadotrophin-induced ovulation at a dose level (0·25 mg. in a 60 g. rat) which has no effect on the ovulatory response to human chorionic gonadotrophin. Higher doses interfered with the action of injected human chorionic gonadotrophin. Ovulation could be induced in the chlorpromazine-blocked animals by the systemic injection of an extract of bovine median eminence, but the sensitivity was too low to use this response for an assay method.

EFFECT OF LUTEINIZING HORMONE ON THE LIPID COMPOSITION OF RAT OVARIES

1978 ◽  
Vol 78 (2) ◽  
pp. 233-238 ◽  
Author(s):  
LINDA A. SCHULER ◽  
G. L. FLICKINGER ◽  
J. F. STRAUSS
Keyword(s):  
Lipid Composition ◽  
Fatty Acyl ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Cholesteryl Esters ◽  
Sterol Esters ◽  
Immature Rat ◽  
Ovarian Cell ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Long Chain

SUMMARY The lipid composition of immature rat ovaries was examined after induction of ovulation with pregnant mare serum gonadotrophin and human chorionic gonadotrophin and subsequent (7–8 days later) stimulation with 10 μg LH. Two hours after the administration of LH, there was a decrease of approximately 50% in the concentration of cholesteryl esters in the ovary. The percentages (by weight) of sterol esters containing stearate, linoleate, eicosatrienoate and arachidonate were reduced by LH treatment, whereas the percentage of the C24:4 acid increased. No changes were observed in either the concentrations or fatty acid composition of phospholipids and triglycerides. These observations suggest that the metabolism of cholesteryl esters is acutely affected by LH and that sterol esters bearing long-chain polyunsaturated fatty acids are preferentially mobilized. Liberation of these unsaturated fatty acyl moieties may have significant effects on metabolism in the ovarian cell.

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