General Presence of Glucocorticoid Receptors in Mammalian Tissues¹

The adrenal glucocorticoids are almost ubiquitous as physiologic regulators in mammalian tissues. The present experiments show that specific cytoplasmic “receptors” for glucocorticoids are present in most tissues of the juvenile rat and rabbit which respond to these hormones. These findings suggest that most physiologic effects of glucocorticoids are mediated through these receptors. A few tissues such as prostate, uterus, and seminal vesicle lack the receptor and thus may not be direct “targets” for glucocorticoids. Receptor levels in juvenile and fetal rabbit tissues are generally similar. However, with rabbit thymus and rat lung there are marked changes during development, suggesting that in some cases developmental changes in receptor levels may determine hormone responsiveness. (Endocrinology94: 998, 1974)