Obesity and its associated insulin resistance and hyperinsulinemia are known to be associated with increased sympathetic activity (increased in circulating catecholamines release) which ultimately leads to an increase in plasma renin activity, that in turn increase the secretion of the powerful vasoconstrictor angiotensin II that is responsible for increasing peripheral vascular resistance and thus causes an increase in blood pressure (38). This evidence concerns the gene REN and obesity due to melanocortin 4 receptor deficiency.