The interrelationships between nonapeptide and steroid hormones secretion by bovine granulosa cells in vitro.
The effects of adding oxytocin (OT) and arginine-vasopressin (AVP) on progesterone and estradiol-17 beta secretion by bovine granulosa cells in culture were studied. The influence of these steroids on OT and AVP release was also evaluated. OT (1, 10, 100 or 1000 mIU/ml) stimulates both progesterone and estradiol output. Small doses (10 pM/ml) of exogenous progesterone or estradiol stimulated a surge in OT, while the intermediate doses (100 or 1000 pM/ml) had no influence, and large doses (10,000 pM/ml) inhibited OT secretion by granulosa cells. Thus, a potential regulatory loop between OT and steroid hormone release by granulosa cells was demonstrated. Stimulation of a surge in steroids by OT, activation of OT release by small doses of steroids and inhibition of OT secretion by excess steroids may suggest the existence of a feedback mechanism regulating these hormones production. Addition of AVP (1, 10, 100 or 1000 pM/ml) inhibited progesterone and stimulated a surge in estradiol, while steroid hormones did not induce AVP release. These data suggest the regulation of ovarian steroidogenesis by AVP, feedback influences are less likely.
Sirotkin
A V
AV
Research Institute of Animal Production, Nitra, Czechoslovakia.
Nitray
J
J
D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism* / Q000494:pharmacology; D002417:Cattle; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000378:metabolism* / Q000494:pharmacology; D005246:Feedback; D005260:Female; D006107:Granulosa Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010121:Oxytocin / Q000378:metabolism* / Q000494:pharmacology; D011374:Progesterone / Q000378:metabolism* / Q000494:pharmacology
D001127:Arginine Vasopressin; D011374:Progesterone; D004958:Estradiol; D010121:Oxytocin