As obesity is a metabolic condition characterized by chronic activation of the renin-angiotensin system [19]–[25], in this study we evaluated whether MAPK cascade activation by AT1R stimulation is associated with myocardial remodeling and has an inhibitory effect on tyrosine phosphorylation of insulin cascade proteins in hearts of obese rats. The gene discussed is AGTR1; the disease is obesity due to melanocortin 4 receptor deficiency.