EDN1 and glomerulosclerosis: These results pointed out whether glomerulosclerosis in diabetic mice was related with ET-1 secretion, whether increased glomerulosclerosis index in ETBR-/- mice was associated with higher ET-1 secretion in ETBR-/- GENs, and why there was higher ET-1 secretion in ETBR-/- GENs.