Differential Uterine Responsivity to Diethylstilbestrol: Apparent Bases for Contrasting Estrogenic Potency

The effects of the naturally occurring steroid estradiol-17β (E) and the synthetic, nonsteroidal estrogen diethylstilbestrol (DES) upon uterine water inbibition, long-term growth, contractile tension development, and actomyosin production were monitored in relation to the temporal pattern of the nuclear retention of the receptor-estrogen complex (REC) for each hormone. Additionally, the relative potency of the two to stimulate glucose oxidation was determined. True uterine growth was stimulated to a greater degree by DES than by E. The differential growth increase promoted by DES was 13.7% and 24.2% at a hormone dose of 0.1 µg and 1 µg, respectively. The augmented growth response to DES was accompanied by a significantly (P