The role of membrane stage in the interaction of cortisol with hepatocytes

We studied the effect of polyvinylpyrrolidone-immobilized cortisol on the distribution of glucocorticoid-receptor complexes in hepatocytes. Immobilized cortisol 1.2-1.5-fold increased the number of glucocorticoid-receptor complexes associated with the nuclei in a dose-dependent manner. The transport of glucocorticoid-receptor complexes into hepatocyte nuclei induced by immobilized cortisol is associated with their activation. Moreover, the ratio between nuclear pools of glucocorticoid-receptor complexes resistant to 0.2 and 0.4 M KCl extraction was changed. It was concluded that glucocorticoid binding to specific plasma membrane sites induced further stages of interaction between the hormone and competent cell.