OBJECTIVETo investigate the effects of carnitine on cardiac function, collagen contents, peroxisome proliferator-activated receptor alpha (PPARalpha) and retinoid X receptor alpha (RXRct) expressions in a rat alcoholic cardiomyopathy modeL.

METHODSAdult male Wistar rats were randomly divided into alcohol group (A) , alcohol/carnitine group (B) and control group. Six months later, protein expressions of collagen I, collagen III, matrix metalloproteinase-9 (MMP-9) and Smad-3 were determined by immunohistochemical staining. Protein expressions of PPARalpha and RXRalpha were detected by Western blot.

RESULTSExpressions of collagen I, collagen III, MMP-9 and Smad-3 were significantly increased in groups A and B compared to group C (P < 0.01 or P < 0.05). Expressions of PPARalpha and RXRalpha (0.156 and 0.192, respectively, in group A; 0.248 and 0.385, respectively, in group B) were decreased compared to group C (P < 0.01 or P < 0.05). These changes were significantly attenuated by carnitine (all P < 0.05, group B vs. group A). Moreover, PPARalpha and RXRalpha positively correlated with EF and FS, and negatively correlated LVEDd, collagen I , collagen III, MMP-9 and Smad-3 (all P < 0.01).

CONCLUSIONPPARalpha and RXRalpha downregulation is significantly correlated with cardiac dysfunction in this alcoholic cardiomyopathy model, carnitine ameliorated the cardiac fibrosis and remodeling possibly through upregulating the metabolic pathways of PPARalpha and RXRalpha.