目前已有约 15种 β -受体拮抗剂应用于临床。心脏选择性 β 受体拮抗剂对心脏 β1 受体的亲和力高于支气管和外周血管的β2 受体 ,在低于临床使用剂量时较非选择性拮抗剂不易引起支气管痉挛 ,但高剂量时其心脏选择性也下降。有些β 受体拮抗剂具有激动剂活性 ,能阻断内源性儿 So far, about 15 β - receptor antagonists have been used clinically. Cardiac selective β-adrenergic receptors have a higher affinity for heart β1 receptors than β2 receptors in bronchial and peripheral blood vessels, which are less likely to cause bronchospasm than non-selective antagonists at doses below clinical use, whereas their heart Selectivity is also declining. Some beta-receptor antagonists have agonist activity that blocks endogenous infants