The effect of “selective”β‐adrenoceptor blocking drugs on the myocardial circulation
The effect of “selective”β‐adrenoceptor blocking drugs on the myocardial circulation
复制标题
“选择性”β-肾上腺素能受体阻滞药物对心肌循环的影响
DOI：
--
复制
发表时间：
1970
影响因子：
7.3
通讯作者：
Roger M. Wadsworth
中科院分区：
文献类型：
--
作者：
J. R. Parratt;Roger M. Wadsworth
1 比较了相对特异性的 β1 肾上腺素受体阻滞药物（普乐洛尔）和相对特异性的 β2 肾上腺素受体阻滞药物（布托胺）对麻醉猫心肌和一般血流动力学的影响。 2普乐洛尔的剂量（10mg/kg，静脉注射）对动脉压、心率、心肌血流量或心肌血管阻力几乎没有影响，但显着降低异丙肾上腺素输注对心率、主动脉dp/dt、心肌血流量、血管阻力和代谢热产生以及心脏努力指数的影响。异丙肾上腺素引起的血管抑制不受影响。 3 布托胺（5 mg/kg，静脉注射）可降低心率、主动脉 dp/dt、心脏努力指数和心肌血流量，并增加心肌血管阻力。这被认为是心肌微循环中存在β2肾上腺素受体的进一步证据。 4 布托沙明后，异丙肾上腺素对心肌血流、心肌血管阻力和心率的影响不受影响，但外周血管扩张作用消失。对主动脉 dp/dt 和心脏努力指数的影响得到加强。 5 结论是，异丙肾上腺素增加心肌血流量的作用主要是由于增加心脏做功和耗氧量，而普奈洛尔对心肌血流量几乎没有直接影响，但消除了释放的儿茶酚胺的心脏兴奋和耗氧作用，其特性表明它应该是一种有效且安全的抗心绞痛药物。
1 A comparison has been made of the effects of a relatively specific β1‐adrenoceptor blocking drug (practolol) and a relatively specific β2‐adrenoceptor blocking drug (butoxamine) on myocardial and general haemodynamics in anaesthetized cats. 2 Practolol, in a dose (10 mg/kg, intravenously) which had little effect on arterial pressure, heart rate, myocardial blood flow or myocardial vascular resistance, markedly reduced the effects of isoprenaline infusions on heart rate, aortic dp/dt, myocardial blood flow, vascular resistance and metabolic heat production, and the cardiac effort index. Isoprenaline induced vasodepression was unaffected. 3 Butoxamine (5 mg/kg, intravenously) decreased heart rate, aortic dp/dt, the cardiac effort index and myocardial blood flow and increased myocardial vascular resistance. This is taken as further evidence for the existence of β2‐adrenoceptors in the myocardial microcirculation. 4 After butoxamine, the effects of isoprenaline on myocardial blood flow, myocardial vascular resistance and heart rate were unaffected but the peripheral vasodilator effect was abolished. The effects on aortic dp/dt and the cardiac effort index were potentiated. 5 It is concluded that the effect of isoprenaline in increasing myocardial blood flow is due predominantly to increased cardiac work and oxygen consumption and that practolol, since it has little direct effect on myocardial blood flow yet abolishes the cardiac stimulant and oxygen wasting effects of released catecholamines, has properties which indicate that it should be an effective and safe anti‐anginal drug.