Abstract
ANP receptor binding and desensitization were demonstrated in the A10 vascular smooth muscle cell (VSMC) line. Concomitantly, the ANP receptor coupled guanylate cyclase activity was reduced by the receptor down-regulation with ANP. The ANP stimulated cGMP accumulation is modulated by arginine-vasopressin, while the arginine-vasopressin mediated cAMP system remained unaffected by ANP. Results suggest negative coupling of arginine-vaso-pressin receptors to the guanylate cyclase activity, and indicate that the vasorelaxant activity of ANP might be regulated in part by arginine-vasopressin via specific receptor sites.