The Influence of 17-Oxo- and 17-Hydroxy-16,17-secoestratriene Derivatives on Estrogen Receptor

Abstract

Since many of newly synthesised D-secoestratriene derivatives showed antiestrogenic effect, with almost a total loss of estrogenic activity, we studied the effects of some of these compounds on estrogen receptors (ER), the translocation of the estrogen-ER complexes formed in presence of competing substances into the nucleus, as well as the binding of these complexes to DNA. The results of uterotrophic effects of analysed derivatives are in agreement with the influence of these compounds on activity and binding parameters of estrogen receptors. Namely, compounds that show relatively high antiestrogenic activity predominantly increaseKdand inhibit translocation to nuclei of radioactive complexes formed in their presence. On the other hand, compounds that do not significantly change binding parameters of estrogen receptors do not show antiestrogenic effect inin vivoexperiments.