[Effect of atriopeptin on the adrenergic mechanism regulating blood vessel tonus]

The direct action of atriopeptin on the cell regulation mechanism of the smooth muscle in isolated segments of the portal vein, aorta, pancreatic and cerebral arteries have been studied. It was found that atriopeptin induce the direct relaxation of the smooth muscle in the main vessels only (aorta, portal vein). In the cerebral and pancreatic arteries atriopeptin stops norepinephrine-induced contractions. The data obtained show that the action of the atriopeptin is mediated by Na+-K+ pump activation of smooth muscle cells and restricts vasoconstriction of catecholamine effect.