Expression of the glucocorticoid receptor in early and late passage C-6 glioma cells and in normal astrocytes derived from aged mouse cerebral hemispheres.

The presence of the glucocorticoid receptor in early and late passage C-6 glioma cells 2B clone and in astrocytes derived from aged mouse cerebral hemispheres has been documented by immunoblotting and/or immunofluorescence labelling. All cell types studied express the glucocorticoid receptor of molecular weight 97 KDa. In addition, in astrocytes derived from aged mouse cerebral hemispheres a smaller molecular weight polypeptide reacting with anti-glucocorticoid receptor antibody was also demonstrated. No difference in the amount of the 97 KDa glucocorticoid receptor between early and late C-6 2B cells was observed, whereas the astrocytes from aged cerebral hemispheres contained considerably reduced amounts of the glucocorticoid receptor compared to C-6 2B cells. Late passage C-6 2B cells were immunofluorescence labelled with the anti-glucocorticoid antibody, the receptor being almost exclusively present in the cytoplasm, with particular concentration in the perinuclear region. The presence of glucocorticoid receptor of molecular weight 97 KDa in glial cells corroborates and expands the existing data based on radioligand binding and immunocytochemical studies. These cell populations can be exploited as a model system for the study of the effects of glucocorticoids on senescence and brain aging.