The Content of a Specific Cell Product in the Vaginal Epithelium of Normal and Neonatally Estrogenized Mice: Its Dependence on an Estradiol-Prolactin Interaction

Abstract

The amount of an immunological marker (CVA) in mucified cells of the mouse vaginal epithelium was quantified by a mixed hemagglutination technique for tissue sections. Immature mice, adult mice which had been estrogenized neonatally (5 .mu.g diethylstilbestrol daily for the first 5 days after birth), and adult non-estrogenized mice were studied. All adult animals were castrated 7-10 days before starting the experiments. Injections of 5 .mu.g estradiol-17.beta. (48 and 24 h before killing the animals) increased the amount of CVA in all 3 groups of animals, but most markedly in the neonatally estrogenized mice. The amount of CVA found following estradiol treatment was decreased in adult animals injected with the ergot alkaloid CB154 (0.5 mg twice daily for 6 days) in addition to the hormone. This partial block of the estradiol-induced CVA response by CB154 was relieved by exogenous rat prolactin. The CVA content in immature animals was not influenced by CB154, given alone or together with estradiol. Combined treatment with estradiol and rat prolactin (3 .mu.g every 8 h for 6 days) increased more efficiently than estradiol alone the amount of CVA in immature and adult nonestrogenized animals. Prolactin injected alone had no effect on the CVA content. These data strongly suggest a synergistic action of estradiol and prolactin in augmenting the epithelial CVA content. Explants of the vaginal wall from normal and neonatally estrogenized mice were grafted into the thigh muscles of newborn mice, every host carrying 1 graft from both types of animals. The CVA content in the epithelium of the 2 grafts increased to the same level in response to estradiol. When the hosts were injected with estradiol and prolactin, the CVA content was higher in grafts from estrogenized donors than in those from nonestrogenized animals. The mucified vaginal cells in adult, neonatally estrogenized mice have a content of CVA which is higher than in nonestrogenized animals. This difference may be ascribed to hormonal factors (estradiol-prolactin) and to persistent effects in the vaginal cells as a result of the neonatal estrogen treatment.