Notes: R-268712 is an inhibitor of activin receptor-like kinase (ALK5; IC50 = 2.5 nM).{69407} It is selective for ALK5 over p38 MAPK (IC50 = 12 µM). R-268712 (1, 3, and 10 mg/kg) reduces renal fibrosis in a model of unilateral ureteral obstruction using transgenic Col1a1-Luc Tg rats, a reporter model for collagen I expression. It also reduces proteinuria and glomerulosclerosis and improves renal function in heminephrectomized rats in a model of glomerulonephritis using antibodies against Thy-1 membrane glycoprotein when administered at doses of 0.3 and 1 mg/kg.