A role for prostaglandins E in LH-induced cholesterol depletion in rabbit ovarian follicles.

Abstract

Previously we had observed that indomethacin prevented LH-induced cholesterol depletion in rabbit ovarian follicles in vivo, indicating a role for prostaglandins in that LH action. In present experiments we have found that 1) pretreatment of the animals with either meclofenamic acid or acetylsalycylic acid, inhibitors of prostaglandin biosynthesis, prevented the LH-induced cholesterol depletion in the follicles; 2) administration of PGE2, but not PGF2α, caused cholesterol depletion in the follicles and the effect was not blocked by indomethacin; 3) simultaneous administration of LH and PGE2 resulted in the same magnitude of cholesterol depletion as was observed after their individual administration; and 4) cholesterol depletion caused by PGE2 was in the ester moiety only, and this effect was similar to the earlier reported effect of LH administration. Thus, it seems that PGE formation may be necessary for expression of the cholesterol depleting action of LH in the rabbit follicle.