β-受体阻滞剂用于治疗高血压病,近年来日益增多,其降压作用主要是使心排出量减少,而周围血管阻力则增加或不变。α-受体阻滞剂能象其它血管扩张剂(如肼苯哒嗪)一样,可减少血管阻力以降低血压。然而,周围血管扩张导致血压降低后可激活压力感受器的内环境稳定机理,引起心率和心排出量增加。Majid等人将β-受体阻滞剂心得平和α-受体阻滞剂酚妥拉明合用,显示至少在急性实验中既减少了心排出量,又降低了周围血管阻力,而且合并用药比单独用药具有更 β-blockers for the treatment of hypertension, increasing in recent years, the main role of its antihypertensive effect is to reduce cardiac output, while the peripheral vascular resistance is increased or unchanged. Alpha-blockers, like other vasodilators (such as hydralazine), reduce vascular resistance to lower blood pressure. However, peripheral vasodilation leads to a decrease in blood pressure that activates the homeostasis mechanism of baroreceptors, causing an increase in heart rate and cardiac output. Majid et al combined beta-blocker phentolamine, a potent and moderate alpha-blocker, showed reduced cardiac output and decreased peripheral vascular resistance, at least in acute trials, Single medication has more