Glucocorticoid receptor is activated by heparin and deactivated by plasmin.

Abstract

Chick thymus glucocorticoid receptor activation was followed in the presence of heparin and/or plasmin. Heparin, at a concentration of 9 microM, accelerated the rate of activation at 25 degrees C without influencing significantly the maximum activated fraction of the 3H-triamcinolone acetonide-receptor complex. On the contrary, 0.7 microM plasmin added prior to incubation at 25 degrees C (activation) of the complex blocked DNA cellulose binding. Thrombin did not influence receptor activation. Added to the activated complex, plasmin resulted in a rapid deactivation, i.e. an irreversible loss of DNA binding capacity. Plasmin and heparin appeared to exert their effects independent of each other in spite of the fact that they are known to interact in the concentration range in question.