Estrogen increases G protein coupled receptor kinase 2 in the cortex of female rats.

Treatment of ovariectomized female rats with estrogen for 2 days reduces alpha2-adrenoceptor binding density by 25%, increases G protein coupled receptor kinase (GRK) activity by 50% and elevates GRK 2 protein levels by 50% in the frontal cortex. These results suggest that estrogen may decrease alpha2-adrenoceptor expression in the frontal cortex of female rats by regulating GRK 2.