[Inhibin, a second testicular hormone (author's transl)]

Germinal epithelium secretes a peptide hormone, inhibin, that regulates FSH secretion. This substance originates inside the seminiferous tubules, from the Sertoli cells, and is transported towards the head of the epididymis where it is reabsorbed, and thus passes into the bloodstream. Inhibin blocks FSH pituitary secretion; its effect on the hypothalamus is debatable. Inhibin also exists in the female, in ovarian follicles and may have a role in follicular growth regulation.