Bioassay of Mouse Pituitary Gonadotropin by Induced Ovulation in Pregnant Mice. Evaluation and Biologic Application. ∗

Abstract

Summary

The ovulatory responses of pregnant mice were evaluated with human chorionic gonadotropin. From these observations the end point response for this material was calculated to be 0.60 I.U. Assays of mouse pituitaries demonstrated a 4-fold decrease in gonadotropin content between parturition and the first postpartum ovulation. This decrease is interpreted as indicating that amounts of pituitary gonadotropin capable of inducing ovulation are released within 3 hours after parturition.