Regional vasorelaxant selectivity of atrial natriuretic factor in isolated rabbit vessels

Synthetic atrial natriuretic factor (ANF) exhibited a marked selectivity in its ability to relax isolated rabbit arteries and veins. The aorta, renal and mesenteric arteries and the facial vein were the most sensitive vessels with the more distal arteries and most veins being relatively unresponsive to ANF. All preparations were effectively relaxed by sodium nitroprusside. ANF (up to 10(-7) M) failed to elicit any effect on isolated rabbit right atria or papillary muscles. The profound regional vasorelaxant selectivity of ANF may help to explain the hemodynamic effects of this substance in vivo.