Effect of Purified Luteinizing Hormone-Releasing Factor (LH-RF) on Plasma LH Activity at Various Stages of the Estrous Cycle of the Rat. ∗

Abstract

Summary

Sephadex-purified LH-RF was injected intravenously into female rats at various stages of the estrous cycle. The effect on plasma LH activity was estimated by the ovarian ascorbic acid depletion technique. LH-RF evoked an increase in plasma LH activity at all stages of the estrous cycle. No definite changes in sensitivity to the LH-RF could be detected, although there was a suggestion that the sensitivity might be enhanced on the morning of proestrus. The experimental results are consistent with the hypothesis that varying rates of release of LH-RF are responsible for the changing rates of release of LH during the estrous cycle.