EFFECTS OF ESTROGENS UPON THE YOUNG OF INJECTED LACTATING RATS1

Abstract

Daily injs. of estrogens were begun in lactating rats on the day of parturition when each litter was reduced to 3 [male][male] and 3 [female][female]. In 1 group different doses of theelin or stilbestrol were given and the young autopsied on the 14th day. In a 2d group, injected daily with 0.1 mg. of these hormones, [male] and [female] offspring were autopsied on days 2, 4, 6, 8, 10, and 12. Sections of the urogenital organs of the young were compared with unin-jected controls. In general, the influence on the urogenital system was proportional to the amt. of hormone administered. Diethylstilbestrol was more effective than theelin. In the [female] young under the influence of the heaviest doses there was an intense cornification of the vaginal epithelium; an atypical pseudostratified uterine epithelium with hyperplastic myometrium; suppression of uterine gland, Fallopian tube and ovarian development. In the [male][male] the testes were small and the accessory sex organs inhibited. There was an abnormal development of the rete tubules, intense epithelial cornification of the ejaculatory duct and prostatic utricle, and marked stratification of the ducts of Cowper''s glands. The influence of the hormones was observed as early as the 4th day. In some [female][female] the vaginal orifice was established as early as the 9th day. The young grew normally for 5 or 6 days and then failed to gain wt. at the normal rate. Lactation did not seem to be suppressed in the mothers. Loss of maternal instinct and neglect of the young probably account in part for their failure to grow normally.