Format

Send to

Choose Destination
Gynecol Endocrinol. 1998 Oct;12(5):307-13.

Effect of growth hormone releasing hormone on luteinizing hormone stimulated progestin biosynthesis in cultured rat ovarian granulosa cells.

Author information

1
Department of Obstetrics and Gynecology, University of Tsukuba, Ibaraki, Japan.

Abstract

In the present study, we examined the effects of growth hormone releasing hormone (GHRH) on luteinizing hormone (LH)-stimulated progestin biosynthesis. Granulosa cells from pregnant mare serum gonadotropin (PMSG)-treated immature rats were cultured in vitro in the absence or presence of ovine. National Institute of Health LH (100 ng/ml) with various doses of GHRH (10(-9), 10(-8) and 10(-7) mol/l) for 24 h. At the end of the incubation period, the incubation media were collected and levels of progesterone, 20 alpha-hydroxypregn-4-en-3-one and cyclic adenosine 3',5'-monophosphate (cAMP) were measured. GHRH significantly stimulated progesterone production and cAMP accumulation in media in a dose-dependent manner in the basal state (p < 0.01 and p < 0.001, respectively). In the presence of LH, GHRH significantly inhibited LH-stimulated progesterone production in a dose-dependent manner (p < 0.01), whereas increasing concentrations of GHRH produced progressive increases in cAMP accumulation (p < 0.05). Since increasing concentrations of GHRH produced progressive decreases in the ratio of progesterone to 20 alpha-hydroxypregn-4-en-3-one production in the LH-stimulated state (p < 0.01), GHRH may be involved in modulation of key steroidogenic steps concerned with progesterone degradation rather than formation in LH-stimulated rat granulosa cells. These results suggest that GHRH may regulate the effects of LH in granulosa cells and play an important role in the reproductive process.

PMID:
9859022
DOI:
10.3109/09513599809012831
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Taylor & Francis
Loading ...
Support Center