FURTHER STUDIES ON THE RELATIONSHIP OF PROGESTERONE TO OVULATION AND LUTEINIZATION IN THE PERSISTENT-ESTROUS RAT

Abstract

-Evidence is presented to show that after spontaneous or exptl. interruption of persistent estrus (in the DA strain), ovulation and luteinization can be induced by a single inj. of progesterone late in diestrus or after the onset of vaginal estrus. The normal cycle was simulated with greatest frequency when this injection was timed to coincide with proestrus. Indirectly, this supports the recent evidence indicating that pro-gesterone secretion is a normal feature of the preovulatory phase of the cycle. Repair of interstitial cells which ac-companied induced luteinization indicates that progesterone, at certain times and under certain conditions, may cause release of LH.