[The study of inhibin/activin formation in human corpus luteum]

The expression of alpha, beta A, and beta B subunit mRNAs is observed in human corpus luteum (CL) of early (3rd day), mid (8th day) and late (15th day) luteal phase during human menstrual cycle. alpha-mRNAs peaked in early CL; beta A-mRNAs appeared only in early CL; beta B-mRNAs was found in early luteal phase and peaked in late CL. The results suggest that (1) inhibin B (alpha.beta B dimer) rather than inhibin A (alpha.beta A dimer) might be the major form of inhibin secreted by human CL; (2) the late CL may produce activin B (beta B.beta B dimer).