FUNCTIONAL AND MORPHOLOGICAL ALTERATIONS OF THE REPRODUCTIVE SYSTEM OF THE FEMALE RAT FOLLOWING PREPUBERAL TREATMENT WITH ESTROGENS1

Abstract

The adm. of diethylstilbestrol or estrone to o rats beginning either at birth or as late as the 14th day and for so short a time as 14 days produced permanent functional and morphological changes in the reproductive system. Typically, these animals tended to. remain in vaginal estrus. Cycles were usually aberrant from the time of puberty, but in a few cases persistent estrus did not appear for 4-10 mos. Persistent-estrus animals copulated repeatedly, but none became pregnant; whereas animals treated for the 1st time at 21 days had normal cycles, copulated, and bore litters. Vaginal estrus was induced readily and could be maintained when treated animals in diestrus were injected with diethylstilbestrol or estrone. Diestrous smears were induced in animals in constant estrus by the adm. o.f (chorionic) gonadotrophin and by unilateral ovariectomy. Ovaries of adult animals given prepuberal treatment were generally small and contained a few developing follicles, numerous large vesicular follicles, and a considerable amt. of interstitial tissue. A high incidence of bursal inflammation, pyometra, cystic glandular hyperplasia, and squamous metaplasia in the uterus and Fallopian tube was noted. Pyosalpinx or chronic salpingitis occurred in 61% of the cases initially treated on or before the 14th day of life. Large tubo-ovarian cysts were found frequently. One of these, and a portion of the uterus showed B. pyocyaneus in pure culture.