Abstract: Objective: To observe the effects of chronic ethanol consumption at different doses on mRNA levels of IR, IRS1, IRS2, GLUT4, AMPK and MEF2 and to approach the possible mechanisms of ethanol on the glucose transportation. Methods: Forty-eight male Wistar rats, randomly divided into four groups, received either distilled water (control group) or ethanol of three different dosages: 5g/(kg·d) (high dose group), 2.5g/(kg·d) (middle dose group), and 0.5g/(kg·d) (low dose group). After treatment for 22 weeks, all animals were sacrificed and the left ventricles were quickly removed and saved for later analysis. The mRNA levels of IR, IRS1, IRS2, GLUT4, AMPKα1, AMPKα2, MEF2A and MEF2D were determined by the RT-PCR method. Results: Compared with the control group, all mRNA levels of IR, IRS1, IRS2, GLUT4, AMPKα1, AMPKα2, MEF2A and MEF2D were decreased in ethanol treatment groups (especially in high dose and middle dose group) (P<0.05). The correlation analysis indicated that GLUT4 had a significantly positive correlationship with IRS1，IRS2, AMPKα1, AMPKα2, MEF2A or MEF2D. Of them, it was closely associated between GLUT4 and IRS1 or MEF2A (P<0.01). Conclusions: Chronic ethanol consumption impairs the mRNA expression of IR, IRS1, IRS2, GLUT4, AMPKα1, AMPKα2, MEF2A and MEF2D of the cardiac muscle in rats.

Key words: Ethanol, Glucose transpoter 4, AMP-activated protein kinase, Myocyte enhancer factor 2, Rats, Wistar