Effect of Actinomycin D on the Estrogen Response in Uteri of Adrenalectomized Rats

Abstract

The response of uterine tissue from mature and immature adrenalectomized rats was studied both in vitro and in vivo following treatment in vivo with estradiol, actinomycin D, or both. In agreement with previous studies of rats with intact adrenals, levels of actinomycin D which inhibited RNA [ribonucleic acid] synthesis in vivo largely prevented the early hormone response. There was, however, a fraction of the response which was insensitive to the action of actnomycin D. This may point to an extragenomic site of estrogen action. While the precise site remains elusive. The early action of the hormone results in the accelerated expression of many genes.