EFFECT OF LUTEINIZING HORMONE ON THE CONCENTRATION OF CYCLIC GMP IN RABBIT OVARIES

1978 ◽  
Vol 79 (2) ◽  
pp. 251-252
Author(s):  
V. V. PATWARDHAN ◽  
A. LANTHIER
Keyword(s):  
Luteinizing Hormone ◽  
Cyclic Amp ◽  
Cyclic Gmp ◽  
Ovarian Tissue ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Direction Opposite ◽  
Stimulation Of

Laboratoire d'Endocrinologie, Hôpital Notre-Dame et Département de Medicine, Université de Montréal, Montréal, Canada (Received 28 June 1978) Cyclic AMP has been implicated as an intermediate in some of the actions of luteinizing hormone (LH) on ovarian tissues, such as stimulation of steroidogenesis (LeMaire & Marsh, 1975). Both in vitro (Marsh, Butcher, Savard & Sutherland, 1966) and in vivo (Armstrong, Dorrington & Robinson, 1976), stimulation with LH results in a rapid increase in the amount of cyclic AMP in ovarian tissues, which precedes the LH-induced increase in steroidogenesis. Recently, studies on rat ovaries (Grinwich, Ham, Hichens & Behrman, 1976; Ratner, 1976; Ratner & Sanborn, 1976) have indicated that the ovarian tissue content of cyclic GMP may also be regulated by LH, but in a direction opposite to that of cyclic AMP. In the rabbit, Goff & Major (1975) have shown that administration of human chorionic gonadotrophin (HCG) causes a biphasic increase

Possible role of cyclic GMP in stimulus-secretion coupling by salt gland of the duck

1979 ◽  
Vol 237 (5) ◽  
pp. C200-C204 ◽  
Author(s):  
D. J. Stewart ◽  
J. Sax ◽  
R. Funk ◽  
A. K. Sen
Keyword(s):  
Cyclic Amp ◽  
Guanylate Cyclase ◽  
Cyclic Gmp ◽  
Salt Gland ◽  
Domestic Ducks ◽  
Stimulus Secretion Coupling ◽  
Stimulation Of

Stimulation of salt galnd secretion in domestic ducks in vivo increased the cyclic GMP concentration of the tissue, but had no effect on cyclic AMP levels. Methacholine, which is known to stimulate sodium transport by the glands both in vivo and in vitro, stimulated ouabain-sensitive respiration in salt gland slices. Cyclic GMP stimulated ouabain-sensitive respiration to the same extent as methacholine. Guanylate cyclase stimulators, hydroxylamine and sodium azide, also stimulated ouabain-sensitive respiration. The stimulation of ouabain-sensitive respiration by methacholine was blocked either by atropine or by removal of calcium from the incubation medium. The stimulation of ouabain-sensitive respiration by cyclic GMP still occurred in the absence of calcium. The above observations seem to indicate that cyclic GMP acts as a tertiary link in the process of stimulus-secretion coupling in the tissue.

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.

ÉTUDE DE L'ACTIVITÉ BIOLOGIQUE IN VITRO DES HORMONES GONADOTROPES

1963 ◽  
Vol 42 (4) ◽  
pp. 509-513 ◽  
Author(s):  
D. Gospodarowicz ◽  
J. Legault-Démare
Keyword(s):  
Incubation Medium ◽  
Cholesterol Synthesis ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Lactogenic Hormone ◽  
Normal Rat ◽  
Stimulation Of

ABSTRACT Human chorionic gonadotrophin (HCG) and lactogenic hormone (LTH or prolactin) were found practically inactive on the incorporation of 14Cacetate into cholesterol of normal rat corpus luteum in vitro. On the contrary, when added simultaneously to the incubation medium, they increased by 90% the labeling of cholesterol. When pseudopregnancy corpora lutea were used, HCG alone stimulated to the same amount, but no stimulation was observed with LTH alone. These results show that the stimulation of cholesterol synthesis is produced by a synergic action of LTH and HCG, LTH being introduced either in vivo (pseudopregnancy) or in vitro.

IMMUNOLOGICAL CROSS REACTION BETWEEN HUMAN CHORIONIC GONADOTROPHIN AND HUMAN PITUITARY GONADOTROPHINS

1966 ◽  
Vol 53 (3) ◽  
pp. 420-428 ◽  
Author(s):  
C. Robyn ◽  
P. O. Hubinont ◽  
E. Diczfalusy
Keyword(s):  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Human Pituitary ◽  
Specific Antisera ◽  
Human Menopausal Gonadotrophin ◽  
Immunological Cross Reaction

ABSTRACT Immunologically mono-specific antisera prepared against human chorionic gonadotrophin (HCG) preparations completely neutralized in vitro as well as in vivo the luteinizing hormone (LH) and also the follicle-stimulating hormone (FSH) activity of both human hypophyseal gonadotrophin (HHG) and human menopausal gonadotrophin (HMG) preparations.

EFFECT OF HUMAN CHORIONIC GONADOTROPHIN ON ADENYLATE CYCLASE ACTIVITY AND TESTOSTERONE CONTENT IN RAT TESTICULAR MITOCHONDRIA

1977 ◽  
Vol 75 (1) ◽  
pp. 119-126 ◽  
Author(s):  
SOREL SULIMOVICI ◽  
M. S. ROGINSKY
Keyword(s):  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Cyclase Activity ◽  
Adenylate Cyclase Activity ◽  
Dibutyryl Cyclic Amp ◽  
Trophic Hormone

The adenylate cyclase activity and the concentration of testosterone in testicular mitochondria from immature rats were measured after administration of human chorionic gonadotrophin (HCG) or dibutyryl cyclic AMP in vivo or in vitro. Intratesticular injection of HCG produced an increase in adenylate cyclase activity which preceded the rise in the level of testosterone, whereas addition of the trophic hormone in vitro resulted in simultaneous increases. Administration of dibutyryl cyclic AMP in vivo enhanced the testosterone content of the mitochondria. However, the cyclic nucleotide added in vitro at concentrations up to 5 mmol/l had no effect. Cycloheximide injected intraperitoneally before the administration of HCG abolished the stimulatory effect of the trophic hormone on the level of testosterone in the mitochondria, whereas chloramphenicol had no effect. These results, although they confirm the role of cyclic AMP as an intermediate in the stimulatory effect of HCG on the concentration of testosterone in rat testis, do not support a role for mitochondrial adenylate cyclase in this action. A protein regulator(s) formed extramitochondrially appears to be involved in the stimulatory effect of gonadotrophins on steroidogenesis.

TESTICULAR ANDROGEN BIOSYNTHESIS FOLLOWING CORTICOTROPHIN AND HUMAN CHORIONIC GONADOTROPHIN ADMINISTRATION

1965 ◽  
Vol 50 (3) ◽  
pp. 365-378 ◽  
Author(s):  
Edgar J. Schoen ◽  
Leo T. Samuels
Keyword(s):  
Interstitial Cell ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Steroid Biosynthesis ◽  
Clear Cut ◽  
Adrenocortical Hyperplasia ◽  
Testicular Interstitial Cells ◽  
Stimulation Of

ABSTRACT The effects of in vivo administration of corticotrophin (ACTH) and human chorionic gonadotrophin (HCG) on rat testes were studied. HCG, administered for 14 days to young rats, led to testicular interstitial cell hypertrophy and hyperplasia, accompanied by stimulation of in vitro testicular androgen production, as manifested by increased 17α-hydroxylase and 17β-desmolase enzyme activities, with no clear-cut effect on 20α-hydroxysteroid dehydrogenase activity. The findings in ACTH-treated animals were similar to those in the saline-treated controls. The lack of influence of ACTH on the testicular enzymes involved in steroid biosynthesis is consonant with the concept that ACTH-dependent bilateral testicular tumours occurring in boys with congenital adrenocortical hyperplasia arise from »adrenocortical rest cells« rather than from testicular interstitial cells.

MATURATIONAL CHANGES IN SHEEP OVARIAN FOLLICLES: GONADOTROPHIC STIMULATION OF CYCLIC AMP PRODUCTION BY ISOLATED THECA AND GRANULOSA CELLS

1978 ◽  
Vol 89 (1) ◽  
pp. 166-172 ◽  
Author(s):  
T. J. Weiss ◽  
D. T. Armstrong ◽  
J. E. A. McIntosh ◽  
R. F. Seamark
Keyword(s):  
Cyclic Amp ◽  
Granulosa Cells ◽  
Follicle Stimulating Hormone ◽  
Adenosine Monophosphate ◽  
Ovarian Follicles ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Camp Production ◽  
Stimulation Of ◽  
Stimulating Hormone

ABSTRACT Theca and granulosa tissues isolated from sheep ovarian follicles of different sizes were incubated in the presence of human chorionic gonadotrophin (HCG; 5 IU/ml) or follicle stimulating hormone (FSH; 5 μg NIH-FSH-S11/ml) for 40 min. Changes in the total amounts of cyclic 3′,5′-adenosine monophosphate (cAMP) were used as an index of the responsiveness of these preparations to the hormones. Thecal tissue of both large (4–6 mm in diameter) and small (1–3 mm) follicles responded similarly to gonadotrophins. Granulosa cells from small follicles failed to respond to stimulation by HCG. FSH, however, consistently increased cAMP production in comparison with controls or cells treated with HCG. Granulosa cells of large follicles responded to both HCG and FSH.

INHIBITION BY MELATONIN OF THE PITUITARY RESPONSE TO LUTEINIZING HORMONE RELEASING HORMONE IN VIVO

1978 ◽  
Vol 76 (3) ◽  
pp. 487-491 ◽  
Author(s):  
K. YAMASHITA ◽  
M. MIENO ◽  
T. SHIMIZU ◽  
ER. YAMASHITA
Keyword(s):  
Luteinizing Hormone ◽  
Carotid Artery ◽  
Anterior Pituitary ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Lh Rh ◽  
Lh Secretion

The rate of secretion of 17-oxosteroids by the testes of anaesthetized dogs in vivo was used as an index of LH secretion. Intracarotid injection of luteinizing hormone releasing hormone (LH-RH, 1, 5 or 10 μg/kg body wt) resulted in an increase in the testicular 17-oxosteroid secretion which was roughly proportional to the dose administered and which reached a maximum 60 min after the injection. Testicular output of 17-oxosteroids was unaffected by administration of melatonin (10 or 100 μg/kg body wt) into the carotid artery. When LH-RH (5 μg/kg) was injected into the carotid artery 3 h after intracarotid injection of melatonin (10 or 100 μg/kg), the testicular response to LH-RH was considerably diminished. Pretreatment with melatonin (100 μg/kg) did not alter the testicular response to human chorionic gonadotrophin (20 i.u./kg body wt) given i.v. It is concluded that melatonin may act directly on the anterior pituitary gland in dogs to inhibit the LH-RH-induced release of LH.

Immunochemical analysis of the human chorionic gonadotrophin-like material secreted by 'normal' and neoplastic urothelial cells

1989 ◽  
Vol 2 (2) ◽  
pp. 107-112 ◽  
Author(s):  
R. K. Iles ◽  
T. Chard
Keyword(s):  
Bladder Tumour ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Sds Page ◽  
Β Hcg ◽  
Bladder Carcinomas ◽  
Immunochemical Characteristics ◽  
Normal Urothelium

ABSTRACT Material with the immunochemical characteristics of human chorionic gonadotrophin (hCG) is produced by bladder tumour cells in vitro and in vivo. In order to characterize this material further, media were collected from 17 cell cultures (three choriocarcinomas, seven bladder carcinomas and seven 'normal' urothelium). The hCG-like material was compared with pregnancy hCG and purified α- and β-subunits by specific radioimmunoassays. Media were also submitted to affinity chromatography and the fractions further analysed by SDS-PAGE and Western blotting. It was shown that both the neoplastic and normal urothelium produced only free β-subunit-like material. This urothelial 'β-hCG' has the same molecular weight and electrophoretic mobility as that present in the intact hCG of pregnancy.

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