Intracellular localization of estrogens in chick liver: increase of the binding sites for the hormone on repeated treatment of the birds with the hormone

Abstract

Binding of [2,4,6,7-³H]-estradiol or its metabolites in the liver tissue of unprimed roosters and those given repeated doses of estradiol has been studied. Electron autoradiographs show the localization of the radioactivity on endoplasmic reticulum, mitochondria, nuclear membrane and nucleolar and extranucleolar chromatin of the hepatocytes. Repeated doses of the hormone to the bird increase the number of binding sites. However, the dissociation constant (K_d) for binding to heavy pellet fraction extractable with 0.4 M KC1 remains essentially unchanged.