Correlation of plasma LH and prolactin levels with the fate of the corpus luteum in the vole, Microtus agrestis

Abstract

Ovulation in the vole occurs about 9-12 h after mating. Following ovulation, the CL [corpus luteum] may be short-lived and start to degenerate within 48 h of formation, or become fully functional when the animal becomes pregnant or pseudopregnant. The fate of the CL depends on whether mating activates a reflex mechanism separate from the controlling ovulation; limited amounts of mating, e.g., a single intromission, often give rise to only short-lived CL; greater amounts of mating stimulate luteal function more consistently. The plasma levels of LH [luteinizing hormone] and prolactin after mating were correlated with the fate of the resulting CL. Marked elevation in plasma LH levels occurred after mating, irrespective of the nature of the CL formed, which probably constitutes the ovulatory stimulus.