2-HYDROXYOESTRADIOL INHIBITS PROLACTIN RELEASE FROM THE SUPERFUSED RAT PITUITARY GLAND

Abstract

The effects of 2-hydroxyoestradiol (2OH-OE₂), dopamine, oestradiol-17β and 2OH-OE₂ plus dopamine on prolactin and LH release from the male rat pituitary gland were examined in vitro. 2-Hydroxyoestradiol reduced prolactin secretion by 51% at 10⁻¹⁰ mol/l and by 34% at 10⁻⁷ mol/l, while oestradiol-17β had no effect at these doses. Dopamine alone (5 × 10⁻⁷ mol/l) decreased prolactin released by 58%, 2OH-OE₂ plus dopamine produced a similar inhibition of 60%. No significant effect on LH release was observed throughout.