The present study examines the effects of prostaglandin F(2α) (PGF(2α)) on basal and agonist-stimulated progesterone (P4) production utilizing long-term, serum-free cultures of bovine luteal cells. During the first 24 h of culture, PGF(2α) had no significant effect on P4 production, and was unable to inhibit either luteinizing hormone (LH)- or dibutyryl cAMP (dbcAMP)-stimulated increases in P4. Treatment with PGF(2α) on Day 1 produced a moderate, nonsignificant (P>0.05) inhibition of cholera toxin (CT)- and forskolin (FKN)-stimulated P4 synthesis. Beyond Day 1 of culture (Days 3-11), PGF(2α) continued to have no significant effect on basal P4 production, but suppressed all stimulatory effects of LH, dbcAMP, CT and FKN. Treatment with indomethacin inhibited prostaglandin synthesis by the cultured cells and also elevated levels of P4 from Days 3 to 11 of culture. Concurrent treatment with PGF(2α) suppressed the steroidogenic effect of indomethacin. From these studies it was concluded that in cultured bovine luteal cells, PGF(2α) does not affect basal P4 production, but is able to inhibit agonist-stimulated P4 production at a site beyond the accumulation of cAMP. This inhibitory effect is not apparent during the first 24 h of culture, but appears after Day 1 and persists throughout the remaining 10 days of the culture period.
All Science Journal Classification (ASJC) codes
- Reproductive Medicine
- Cell Biology