Abstract: The effect of fish oil on the basal left ventricular function and changes of left ventricular function induced by isoproterenol (ISO) were demonstrated in our study. The detennina-tion of cardiac perfonnance in vivo showed that supplementation with fish oil (EPA and DHA, 70%, 1.4 ml/kg) had no significant effect on basal cardiac perfonnance, while it could significantly inhibit changes of +dp/dtmax, Vpm and HR induced by ISO (0.4 μg/ kg, 4.0 μg/ kg, 40 μg/ kg) intrave-nously.The results suggested that supplementation with fish oil perhaps affected the function of β-adrenoceptors on rat myocardial membrane.

Key words: Fish oil, EPA and DHA, Left ventricular function, β-adrenoceptor