After physiological stress older male Wistar rats showed a faster normalization of the corticosterone level in serum and of the concentration of unoccupied glucocorticoid receptors in liver cytosol than young ones, which is contrary to female rats. The nuclei binding of glucocorticoid receptor complexes (GRC) was significantly reduced in older control animals compared with young ones. The nuclei binding of GRC was reduced in young rats until 60 min after stress compared to controls, whereas it had been increasing in older animals at this time. Contrary to female rats, the addition of the endogenous ATP-stimulated translocation promoter (ASTP) alone or together with ATP did not elevate the nuclei binding, but it groups. Crossing experiments using nuclei of controls and GRC of control and stressed animals, resp., seem to disclose a longer association of GRC with the nuclei in old animals than in young ones.