Reciprocal control of oxytocin and cAMP production by porcine granulosa cells in vitro.
Oxytocin and cAMP accumulation in the medium after 4 days incubation of porcine granulosa cells was measured and confirmed the production of these substances by porcine ovaries. Both cAMP analogue dbcAMP (10, 100, 1,000 or 10,000 microM/ml) and 3-isobutyl-1-methyl-xanthine (intracellular cAMP metabolization inhibitor, 0.1, 1, 10 or 100 microM/ml) additions increased granulosa cells oxytocin production in a dose-dependent manner. Low doses of oxytocin or posterior pituitary extract (10 or 100 mIU/ml) had no significant effect on granulosa cAMP output, but higher dose (1,000 mIU/ml) inhibited it. Thus, porcine ovarian oxytocin production can be stimulated via cAMP-dependent intracellular mechanisms. On the other hand, excess of oxytocin can inhibit ovarian cAMP production through a ultra-short loop negative feedback regulation.
Nitray
J
J
Research Institute of Animal Production, Nitra, Czechoslovakia.
Sirotkin
A V
AV
D000818:Animals; D000242:Cyclic AMP / Q000096:biosynthesis* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D006107:Granulosa Cells / Q000378:metabolism*; D066298:In Vitro Techniques; D010053:Ovary / Q000378:metabolism; D010121:Oxytocin / Q000096:biosynthesis* / Q000494:pharmacology; D013552:Swine / Q000378:metabolism*
D010121:Oxytocin; D000242:Cyclic AMP