Scanning electron microscopic changes in vaginal epithelium of suckling neonatal mice in response to estradiol or insecticide chlordecone (Kepone) passage in milk.

Groups of lactating mice received daily 9 intraperitoneal injections consisting of the following chemicals: sesame oil only or 10.0, 20.0 or 40.0 micrograms estradiol-17 beta or 250.0, 500.0 or 1000.0 micrograms chlordecone. Reproductive tracts and vaginal surface changes were examined in the neonates that were nursed by the treated lactating dams for 12 days. Ingestion of milk from dams treated with estradiol or chlordecone did not produce any toxic symptoms or mortality in the offspring. However, the neonatal reproductive tract weights and vaginal epithelium exhibited significant changes indicating the passage of these compounds in milk. The vaginal epithelium in the neonates that nursed the estradiol-treated dams exhibited mucification, keratinization, and desquamation. Neonates that ingested milk from chlordecone-treated dams exhibited similar but dose-dependent changes in the vaginal canals. However, the keratinized vaginal cells in these mice were morphologically different and lacked the well-developed microridge patterns on the cell surfaces that characterized keratinized cells in the estradiol group. The significance of these changes on the reproductive functions in adult animals are discussed in the text.