Mechanism of the HDL2 stimulation of progesterone secretion in cultured placental trophoblast.

Abstract. A newly developed model for perfusion of the isolated rat ovary was employed to study the interactions of Prl with PGF2α in respect to the effects of LH on cAMP formation and progesterone production in the 5 day old corpus luteum of the PMSG-treated rat. An inhibitory effect of PGF2α on both basal and LH stimulated progesterone secretion was found. This block also involved inhibition of the ovarian cAMP release which was not associated with a reduction of the flow of the medium to the ovary. When Prl was present in the medium the PGF2α block of LH-induced cAMP release was reversed. However, Prl failed to restore block of LH stimulation of progesterone secretion in 4 out of 9 experiments, indicating an additional site of action of PGF2α distal to the cAMP in these experiments.

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Stimulation of progesterone secretion by recombinant follistatin-288 in human granulosa cells.

Endocrinology ◽

10.1210/endo.132.4.8384994 ◽

1993 ◽

Vol 132 (4) ◽

pp. 1750-1756 ◽

Cited By ~ 6

Author(s):

W Li ◽

S Khorasheh ◽

B H Yuen ◽

N Ling ◽

P C Leung

Keyword(s):

Granulosa Cells ◽

Human Granulosa Cells ◽

Progesterone Secretion ◽

Stimulation Of

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Catecholamines and ascorbic acid as stimulators of bovine ovarian oxytocin secretion

Journal of Endocrinology ◽

10.1677/joe.0.1140423 ◽

1987 ◽

Vol 114 (3) ◽

pp. 423-430 ◽

Cited By ~ 24

Author(s):

M. R. Luck ◽

B. Jungclas

Keyword(s):

Ascorbic Acid ◽

Granulosa Cells ◽

Time Course ◽

Culture Medium ◽

Stimulatory Action ◽

Variable Effect ◽

Progesterone Secretion ◽

Agonistic Activity ◽

Cells Cultured ◽

Stimulation Of

ABSTRACT The effects of catecholamines and ascorbic acid on cultured bovine granulosa cells have been examined to assess their possible role in the initiation and maintenance of luteal oxytocin secretion. The actions of these agents have also been compared with the previously reported ability of follicular theca tissue to enhance oxytocin secretion. Using granulosa cells cultured in serum-supplemented medium, we observed a highly significant enhancement of oxytocin secretion in the presence of adrenaline and noradrenaline, particularly over the concentration range 1–10 μmol/l. This effect was accompanied by smaller and less consistent changes in progesterone secretion and did not involve any change in the time-course of oxytocin secretion. Acetylcholine was without effect. Ascorbic acid stimulated oxytocin secretion when used alone over a range of concentrations, but was also able to synergize with adrenaline. Lactic acid was ineffective. The stimulation of oxytocin secretion by adrenaline could be blocked by equimolar propranolol, but the stimulation of progesterone was not blocked. Propranolol had a variable effect on the ability of theca tissue to stimulate oxytocin secretion by granulosa cells but the results also suggested the presence of some β-agonistic activity in the culture medium. We conclude, first, that catecholamines may be involved in the regulation of ovarian oxytocin secretion, secondly, that ascorbate may regulate oxytocin secretion through its involvement in the biosynthesis of oxytocin but also through interaction with catecholamines and, thirdly, that the stimulatory action of theca tissue probably does not involve the action of β-agonists. J. Endocr. (1987) 114, 423–430

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Cortisol stimulation of estradiol and progesterone secretion by human granulosa cells is independent of follicle-stimulating hormone effects**Supported by the United States Public Health Services grant HD 06274-14 and by the Mellon Foundation.††Presented at the Fifth World Congress on in Vitro Fertilization and Embryo Transfer, Norfolk, Virginia, April 5 to 10, 1987.

Fertility and Sterility ◽

10.1016/s0015-0282(16)59889-6 ◽

1988 ◽

Vol 49 (5) ◽

pp. 813-816 ◽

Cited By ~ 22

Author(s):

Zion Ben-Rafael ◽

Claudio A. Benadiva ◽

Carmen J. García ◽

George L. Flickinger

Keyword(s):

United States Public Health ◽

The United States ◽

Public Health Services ◽

World Congress ◽

Vitro Fertilization ◽

Human Granulosa Cells ◽

Progesterone Secretion ◽

Hormone Effects ◽

Stimulation Of

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DIRECT STIMULATION OF BOVINE OVARIAN PROGESTERONE SECRETION BY LOW CONCENTRATIONS OF a-INTERFERON

Journal of Endocrinology ◽

10.1677/joe.0.135r005 ◽

1992 ◽

Vol 135 (2) ◽

pp. R5-R8 ◽

Cited By ~ 5

Author(s):

M.R. Luck ◽

J.A Shale ◽

J.H. Payne

Keyword(s):

Corpus Luteum ◽

Granulosa Cells ◽

Dna Content ◽

Hormone Secretion ◽

Direct Stimulation ◽

Serum Free ◽

Ovarian Cells ◽

Progesterone Secretion ◽

Low Concentrations ◽

Stimulation Of

ABSTRACT The ruminant conceptus secretes proteins during early pregnancy which maintain the corpus luteum. These trophoblast proteins are related to the αII-interferons and prevent luteolysis indirectly by disrupting the secretion of endometrial prostaglandin. Although trophoblast interferons appear to be largely confined to the uterine lumen, it remains possible that they also act peripherally. This report describes in vitro studies which suggest that interferon may influence hormone secretion by the ovary directly. The study employed i) a well defined serum-free culture model in which bovine granulosa cells secrete the luteal hormones progesterone and oxytocin, and ii) serum-free and serum-supplemented cultures of cells from early CL. Dose-response experiments were performed using bovine recombinant α-interferon (brIFN). Progesterone and oxytocin secretions were measured over 4-5 days of culture and DNA content was also determined. Low concentrations of brIFN (10−15 mol/l to 10−11 mol/l) stimulated progesterone secretion by granulosa cells by up to three fold, without significantly affecting oxytocin concentrations or culture DNA content. Concentrations of 10−10 mol/l to 10−7 mol/l suppressed progesterone secretion in a log dose-related manner (r=0.97) with evidence of toxicity (lower oxytocin concentrations and significantly reduced DNA compared with controls). Progesterone secretion by luteal cells in serum-free culture was stimulated in the presence of 10−15 mol/l brIFN, whilst high concentrations again caused inhibition. The data show that ovarian cells can respond directly to low concentrations of interferon-like proteins. They also demonstrate an inhibition by high doses which may mask the stimulatory effect in this model. The data suggest that the early corpus luteum may be directly influenced by α-interferon. A stimulation of progesterone, but not of oxytocin, secretion from ovarian cells would be consistent with a role for conceptus proteins in maintaining the corpus luteum of pregnancy.

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