THE DEPRESSION OF ESTRONE-INDUCED UTERINE GROWTH BY PHENOLIC ESTROGENS WITH OXYGENATED FUNCTIONS AT POSITIONS 6 OR 16: THE IMPEDED ESTROGENS

Abstract

Two small groups of steroids in the estrane series—here designated as impeded estrogens,—represent a class of compounds which differ from the majority of estrogenic substances in exerting certain unusual influences on growth of the uterus. The induction of these effects previously was considered to be peculiar to estriol. The unusual growth properties common to impeded estrogens are twofold: (a) after the threshold dosage required to initiate growth has been reached, the slope of the curve of increment of uterine weight in response to increased steroid dosage is very gradual rather than steep; (b) these compounds possess the ability to inhibit to a limited extent the uterine growth induced by estrone administered concurrently.