OA enhances atherosclerotic lesion development. (A) Oil Red O staining of atherosclerotic lesions in the aortic root at the level of the aortic valves. Magnification ×40. (B) Quantitative analyses of the proximal aorta atherosclerotic lesion areas in the normal chow (NC), NC plus acipimox (NC+A), oleic acid (OA) and OA plus acipimox (OA+A) groups. (C) Plasma levels of FFA in the four groups. Data are expressed as mean ± SEM. n = 6 mice per group. * p < 0.05, ** p < 0.01 compared with the control group, # p < 0.05 compared with the cells treated with OA alone. NC, normal chow; OA, oleic acid; A, acipimox; FFA, free fatty acid.