Electron-microscopic study on the development of permanently proliferated and cornified vaginal epithelium in mice...

In the vaginal epithelium of mice given 5 daily injections of 100 microgram 5 alpha-dihydrotestosterone from the day of birth, highly electron-dense cells with numerous cytoplasmic processes appeared in the basal layer within 35 days after the last injection. These cells were similar to the B cells reported in earlier works in neonatally estrogen-treated mice undergoing ovary-independent, permanent proliferation and cornification. The present electron-microscopic study suggests that the permanently proliferating, highly electron-dense cells are derived from electronlucent cells (clear cells) appearing in the basal layer of the vaginal epithelium 15-20 days after neonatal androgen treatment.