Effects of LH-RH agonist or LH-RH immunoneutralization on pituitary and ovarian LH-RH receptors in female rats.

Hyperstimulation of pituitary function using daily injections of 50,500 or 5000 ng LH-RH agonist for 3 weeks or hypostimulation by immunoneutralization of endogenous LH-RH led to disrupted oestrous cycles and profound changes in ovarian morphology. Despite this, the number of pituitary and ovarian LH-RH receptors remained within the range found in normally cyclic animals. Autoradiography confirmed that specific binding was located in theca, granulosa and luteal cells. These results suggest that autoregulation of pituitary and ovarian LH-RH receptors is not of primary importance in the cyclic female rat.