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.