RESUMEN
Effects of fish oil on B-adrenoceptors as well as the activity of adenylate cyclase (AC) on rat myocardial membrane were investigated. Supplementation with fish oil had no significant effect on basal activity of AC on myocardial membrane, whereas it could markedly inhibit the AC activity stimulated by isoproterenol (ISO). Radioligand binding assays showed that supplementation with fish oil had no effect on Bmax, and Kd, compared with saline control. However, supplementation with sheep oil could markedly reduce both the Ka and Bmax, compared with saline control. And the Ka value of sheep oil group was greatly decreased than that of fish oil group. The results suggested that supplementation with fish oil affected mainly on the activation of AC and not on B-adrenoceptor itself.
RESUMEN
The effect of fish oil on the basal left ventricular function and changes of left ventricular function induced by isoprenaline (ISO) was demonstrated in the study. The determination of cardiac performance in vivo showed that supplementation with fish oil (EPA and DMA,70%, 1. 4 mL/kg) had no significant effect on basal cardiac performance,while it could significantly inhibit the gains of +dp/dtmax,Vpm and HR induced by ISCK10 6 mol/L, 10 3 mol/L, 10 4 mol/L) introvenously. The result suggest that supplementation with fish oil have some effects on the function of B-adrenoceptors on rat myocardial membrane.