[Mechanisms of action of estrogens physiological and pharmacological aspects of hormonal "receptivity". The anti-estrogens (author's transl)].

Receptivity to estrogens may indeed depend on the concentration of the corresponding receptor in the target cells. This concentration varies physiologically, and would possibly explain, at least in part, certain hormonal interactions and receptivity changes during the physiological cycles. The modifications of receptor concentrations could perhaps be of significance in explaining the effects of "priming" and the negative influence of one steroid on another. The simultaneous presence of different receptors for the same hormone or the competition of different hormones for the same receptor offer interesting pharmacological possibilities. It has already been shown that the characteristics of receptors can explain the differences between a natural hormone like estradiol and diethylstilbestrol, the hormone with the most common synthesis. A series of synthetic derivatives (triphenylethylene) seem to offer the possibility of an antagonist effect without pollution by significant estrogenic activity, and the potential therapeutic consequences are immense. Regulatory proteins, the steroid hormone receptors, provide some of the most advanced models for rational physico-chemical and physiological approaches to pharmacological and therapeutical problems.