Evidence for glucocorticoid regulation of the rat vasopressin V1a receptor gene.

ABSTRACT

WRK-1 cells express vasopressin V1a receptors. Twenty-four-hour treatment of these cells with dexamethasone (DEX) resulted in an increase in [3H]AVP binding that was maximal at 12 h, and could be blocked by addition of RU 38486. The increases in [3H]AVP binding were paralleled by increases in V1a receptor mRNA. The in vivo effects of glucocorticoids (GCs) on V1a receptor binding in hepatic tissue were also investigated in adrenalectomized and hormone-replaced rats given either DEX or aldosterone (ALDO). DEX effectively increased V1a receptor binding site density whereas ALDO had no effect. The DEX effects on V1a receptor mRNA and binding strongly implicate glucocorticoids in the regulation of V1a receptor gene expression.