Effect of insulin on natriuretic peptide gene expression in porcine heart

•Acute euglycemic hyperinsulinemia activates Akt signalling pathway in the porcine myocardium.•BNP mRNA content in the left ventricle decreased following acute euglycemic hyperinsulinemia.•No changes in ANP mRNA contents were demonstrated as a result of insulin infusion.•Acute euglycemic hyperinsulinemia was not associated with changes in circulating proANP concentrations. Gut hormones affect cardiac function and contractility. In this study, we examined whether insulin affects the cardiac atrial natriuretic peptide (ANP) and B-type natriuretic peptide (BNP) gene expression and release of proANP-derived peptides in pigs. Anaesthetized pigs were included in an experimental study comparing the effect of hyperinsulinemia in 15 pigs submitted to two different protocols versus 11 control pigs receiving saline infusion. Phosphorylation of Akt on Thr308 was determined by western blotting with a pAkt-Thr308 antibody. The mRNA contents of ANP and BNP were determined with real-time PCR; plasma and cardiac tissue proANP was measured with an immunoluminometric assay targeted against the mid-region of the propeptide and a processing-independent assay. Insulin stimulation increased phosphorylation of Akt Thr308 in both left atrium and left ventricle of porcine hearts (p