On the occurrence of the œstrous cycle after X-ray sterilisation.—Part I. Irradiation of mice at three weeks old

Abstract

Control of the uterine cycle by ovarian structures was studied by x-ray sterilization of 9 mice at weaning, and subsequent observation of the reproductive organs. Of 25 mice so treated, 22 experienced at least 1 period of oestrus after puberty, and many showed a series of cycles of normal length. Autopsy showed that none had oocytes, graafian follicles, or follicular tissue in the ovaries, indicating that these structures are not essential in producing the normal uterine cycle. The author''s conclusion is that there is a cyclic mechanism in the ovary, resident in the inter-follicular tissue, which secretes most of the oestrus-producing hormone; and that this mechanism is responsible for the uterine and the coincident ovarian cycles.