Glucocorticoids and lymphocytes. I. Increased glucocorticoid receptor levels in antigen-stimulated lymphocytes.

Recently a 2- to 3-fold increase in the number of glucocorticoid receptors in human peripheral lymphocytes has been noted after in vitro mitogen stimulation. Here, we extend these observations to in vivo immunization. After unilateral immunization of adrenalectomized male rats, a 50% increase in glucocorticoid receptor sites per cell, determined by binding of dexamethasone, was observed in cell suspensions of homolateral lymph nodes over those from the contralateral nonimmunized side of the same animal. The association constant for dexamethasone was similar in both groups, as was the stereospecificity for various steroids, the time course of cytoplasmic and nuclear association, and cytoplasmic-to-nuclear translocation. Despite a 50% increase in the number of glucocorticoid receptor sites per cell, the cells from the homolateral and controlateral lymph nodes were equally sensitive to the inhibitory effects of dexamethasone, as determined by measurements of the incorporation of radiolabeled precursors of protein, RNA, and DNA, or measurements of in vitro cell survival.