Ontogenic expression of estrogen receptor coactivators in the reproductive tract of female mice neonatally exposed to diethylstilbestrol.

Ontogenic expression of p300, steroid receptor coactivator-1 (SRC-1), GR-interacting protein-1 (GRIP1) and p300/CBP cointegrator associate protein (p/CIP) was examined using an immunohistochemical method in the genital tract of female mice neonatally exposed to diethylstilbestrol (DES). Mice were injected with 4 microg of DES for 5 days and killed on days 10, 15 and 21; some mice were killed on day 4 after three injections. The p300 immunoreactive protein in the epithelial cells of the oviducts, uteri, and vaginae was almost constant during development independent of neonatal DES exposure, while the stromal cells exhibited a weaker reaction than that of the vehicle-treated controls on days 4 and 10. Neonatal DES exposure caused no significant changes in the SRC-1 and p/CIP expression patterns but decreased the GRIP1 expression with development in the reproductive tract. The constitutive expression of coactivators in both epithelial and stromal cells may play a role in the estrogen imprints through ER alpha systems during the period of DES treatment.