Effect of atrial natriuretic factor on angiotensin converting enzyme

We studied the effects of atrial natriuretic factor on the conversion of angiotensin I to angiotensin II. Atrial natriuretic factor had a novel effect on angiotensin I conversion. Pulmonary artery endothelial cells converted 1.22 nmol/min/dish of [125I]angiotensin I to II in the absence of atrial natriuretic factor, but this activity was suppressed by atrial natriuretic factor. When atrial natriuretic factor was added to pulmonary artery endothelial cells, the conversion of angiotensin I to angiotensin II was suppressed 0.475 nmol/min/dish at 10(-6) M of atrial natriuretic factor.