The observed discrepancy between impairment of myocardial cGMP-signalling and unchanged plasma cGMP levels in DiabCo vs. Co animals might be the consequence of diabetes-associated increase in ANF levels and the subsequent activation of natriuretic peptide receptors and particulate guanylate cyclase (pGC) in organs other than the heart, as plasma cGMP is seen as an overspill of intracellular cGMP from various tissues [36]. This evidence concerns the gene NPPA and diabetes mellitus.