PHYSIOLOGY OF THE CORPUS LUTEUM

Abstract

In previous studies it had been shown that corpus luteum extracts (progestin) produce proliferation of the endometrium regularly in the adult castrated [female] guinea-pig, but seldom in the immature [female] . It was assumed that, since corpus luteum never occurs in the normal animal until after sexual maturity, pure corpus luteum preparations would have no effect on the immature animal, and that the variations in response were due to varying amounts of oestrin (to which the uterus of the immature rabbit is very sensitive) in the crude extracts. This theory was tested by bringing the uteri of 10 immature rabbits to maturity by injection of oestrin and then treating with progestin; all showed complete proliferation of the endometrium, while of 12 animals given only progestin, 5 showed no growth or proliferation, 5 showed some growth and traces of proliferation, and 2 showed some growth and a moderate proliferation.