Pressor-Type Vasopressin Receptors in the Adrenal Cortex: Properties of Binding, Effects on Phosphoinositide Metabolism and Aldosterone Secretion

Specific, high affinity sites that bound tritium-labeled arginine-vasopressin (3H-AVP) were detected in a crude membrane fraction of rat adrenal capsules (chiefly zona glomerulosa). Binding displacement experiments with peptide analogs of AVP suggested that the binding site is a pressor (V1) type receptor for AVP. When added to dispersed rat adrenal glomerulosa cells, vasopressin (10(-8)-10(-6)M) stimulated the incorporation of 32P-phosphate into phosphatidylinositol, and the effect was blocked by the AVP receptor antagonist peptide d(CH2)5Tyr(Me)AVP. Vasopressin also increased the breakdown of phosphatidylinositol-4,5-bisphosphate within 1 min after its addition to the incubation medium. Superfused zona glomerulosa cells responded to AVP (10(-8)-(-6)M) by increasing their aldosterone production. The response could be blocked by the antagonist peptide. These data show that functionally active V1 receptors are present in rat glomerulosa cells, and suggest that vasopressin may regulate the function of the adrenal glomerulosa.