Histopathology of MCAD+/+ and MCAD−/− Mice (A) MCAD+/+ mice had no evidence of hepatic steatosis following a 24-h fast. Liver section with Oil-Red O stain. (B) Hepatosteatosis in MCAD−/− mouse following a 24-h fast. Oil-Red O stained liver sections revealed severe and diffuse microvesicular and macrovesicular hepatic steatosis in MCAD−/− mice. (C and D) Diffuse cardiomyopathy with chronic active multifocal myocyte degeneration and necrosis in MCAD−/− mice.