PRODUCTION OF OVULATION BY GONADOTROPHIC EXTRACTS*

Abstract

The luteinizing and follicular-stimulating fractions of anterior pituitary extracts have rarely been utilized in the ovulation studies which have been made. Furthermore, few studies have been made on immature female animals in which the normal gonadotrophic activity of the animal’s own pituitary is thought to be at a minimum. It was pointed out by Hertz and Hisaw (1934) that ovulation occurred in 45 per cent of the juvenile rabbits to which they administered subcutaneously, first follicular-stimulating and then luteinizing extract, each over a three-day period. Ovulation did not occur in young rabbits treated with unfractionated pituitary extracts, purified follicular-stimulating extracts, or luteinizing extracts alone. In working with beef pituitaries Evans and associates (1933) reported the failure to produce ovulation in immature female rats by injections of crude extracts, but when their preparations were subjected to further purification ovulation was produced by their administration. It has seemed n...