Possible regulation of renin release by ANP in dogs with heart failure

We investigated whether atrial natriuretic peptide (ANP) contributed to the regulation of renin release during the development of experimental heart failure in dogs. Significant increases of plasma ANP and plasma guanosine 3',5'-cyclic monophosphate (cGMP) levels were observed in dogs with mild heart failure induced by 6 days of rapid ventricular pacing. However, plasma renin activity (PRA) was not elevated, despite the significant decreases in renal plasma flow and mean arterial pressure. An inverse correlation between PRA and the ratio of plasma cGMP to ANP (rs = -0.59, P < 0.05) was found in dogs subjected to 9 days of rapid pacing. In dogs with advanced heart failure induced by 15-24 days of rapid pacing, the plasma cGMP level did not increase further, despite the progressive increase in plasma ANP with the resultant significant increase in PRA (P < 0.05). These findings suggest that attenuation of the inhibitory effect of ANP on renin release during the development of severe heart failure may be an important factor in the activation of the renin-angiotensin system.