Effect of Different Steroids on Prolactin Secretion in Pituitary-Hypothalamus Organ Co-Culture

Various steroids were added to pituitary culture or pituitary-hypothalamus co-culture in vitro, and their effect on pro-lactin release was studied. 1. Estradiol and hydrocortisone are strong stimulants of pro-lactin release, apparently acting directly through the pituitary. 2. 3-Alpha-hydroxy-11, 20-diketo-pregnane-3-hemisuccinate and, to a lesser degree, progesterone are depressants of prolactin release, acting directly on the hypophysis. 3. Testosterone does not affect prolactin release from the pituitary.