In the present study, using experimental models of both type I and a model of spontaneous type II diabetes, the Israeli sand-rat, we demonstrated selective antagonism of the SDF-1-CXCR4 pathway reduces myocardial fibrosis, to a degree equivalent to that seen with angiotensin receptor blockade in the absence of an effect on blood pressure. The gene discussed is CXCR4; the disease is Myocardial fibrosis.