Current perspectives of inhibin biology

Inhibin is generally considered to be a feedback regulator of FSH secretion, but significant progress in the field of inhibin biology over the past four years has widened our perspective of inhibin and its production, regulation and action. Firstly, inhibin is a member of a larger family of hormones, secondly it is produced by organs other than the gonads, and thirdly its action is not confined to the pituitary gland. In this review we will outline the isolation and characterization of inhibin related peptides and their production by the Sertoli and granulosa cells of the testis and ovary. With this information in mind, more recent studies concerning the measurement, production, regulation and action of inhibin and inhibin-related proteins will be discussed, in an effort to alert the reader to the contemporary and controversial issues concerning inhibin biology.