Studies of the desensitization of atrial natriuretic factor and nitroglycerin in rat aortic rings
1. Atrial natriuretic factor (ANF) relaxes vascular smooth muscle through activation of particulate guanylate cyclase and generation of cyclic GMP. 2. From other laboratories, there is some evidence from cultured vascular smooth muscle cell studies for homologous desensitization of ANF-induced cGMP production and down-regulation of ANF receptors. 3. This series of studies demonstrates that homologous desensitization of ANF-induced relaxation of rat aortic ring preparations also occurs. 4. Heterologous desensitization could not be demonstrated to the vasoactive peptides angiotensin II or vasopressin, nor to nitroglycerin which has previously been shown to exhibit heterologous desensitization with other nitrovasodilators and shares some common elements in the pathway to vascular smooth muscle relaxation with ANF.