EFFECT OF A GONADOTROPIN INHIBITING SUBSTANCE ON OVARIAN HISTOLOGY IN MICE

The effect of a gonadotropin inhibiting substance, which was prepared from the precipitate of acidified urine of adult males by extraction with a borate buffer solution, on the ovarian structure and the ovulation in immature mice given HCG was studied. No ovulation occurred in the mice injected HCG with the inhibitor. Atretic and enlarged ovarian follicles with proliferated granulosa cells and developed antra were formed 18 hours after the injection in these animals. Later the enlarged follicle which failed to rupture without the stimulation of LH reached a stage of atresia or a corpus luteum of atresia at the center of which the ovum was present. These findings confirmed that the inhibiting substance suppressed mainly the action of LH and that its action was not a delay of ovulation but its suppression. © 1968.