EFFECT OF TESTOSTERONE PROPIONATE ON THE RELEASE OF FSH FROM THE PITUITARY GLAND

Abstract

On the basis of a. study of changes in follicle stimulating hormone (FSH) levels in rat pituitary glands, obtained at various times after orchiectomy, it has been previously suggested that the Leydig cell secretions may regulate the release of FSH from the pituitary gland (Steinberger and Duckett 1966). This hypothesis was put to test in the present study. FSH levels have been determined in the pituitary gland and plasma of normal, testosterone-treated, orchiectomized, and orchiectomized testosterone-treated rats. A marked drop of pituitary FSH levels, associated with an elevation of plasma FSH levels, was observed in orchiectomized rats. Administration of testosterone to orchiectomized rats prevented the drop in pituitary FSH levels and rendered the blood levels undetectable. These results are interpreted as supporting the hypothesis that testosterone has an inhibitory effect on the release of FSH from the pituitary gland.