Effect of PGF-2 alpha on progesterone production in swine luteal cells at different stages of the luteal phase.

Suspensions of luteal cells were prepared by enzymatic dispersion of pig corpora lutea obtained at specific times during the estrous cycle. Luteal cells from early corpora lutea produced more progesterone (4.73 +/- 0.84 nmol/10(6) cells, day 3) than those from late diestrus (0.73 +/- 0.04 nmol/10(6) cells, day 15); (P less than 0.05). Bovine LH enhanced progesterone production in a dose dependent manner particularly in cells from 9 to 15 day corpora lutea. Also PGF-2 alpha enhanced progesterone output in cells from mid-late corpora lutea. PGF-2 alpha did not exert any antigonadotropic effect since it further increased the progesterone production induced by LH. Luteal cells produced PGF-2 alpha with levels ranging between 1.6 and 2.7 pmol/10(6) cells throughout the whole luteal phase. The cellular content of cAMP was markedly increased by LH (556 +/- 60%) while it was not affected by PGF-2 alpha. Plasma membrane receptors for PGF-2 alpha were not detected in the analyzed tissue.