多粘菌素B(polymyxin B简称PXB)属多肽类抗生素。临床上主要用于抗革兰氏阴性细菌感染。它尚能阻滞骨骼肌神经肌肉接头和神经节冲动的传递,大剂量有抑制心脏等作用。本实验室曾在动物实验中发现PXB有显著的抗心律失常作用。对结扎冠状动脉左旋支,乌头碱所致心律失常的抑制作用,显著大于利多卡因。本文研究PXB对心室肌动作电位的影响,以探讨其抗心律失常机制。 Polymyxin B (polymyxin B referred to as PXB) is a peptide antibiotic. Clinically, mainly for anti-gram-negative bacterial infections. It is still able to block skeletal muscle neuromuscular junction and ganglia impulse transmission, high-dose inhibition of the heart and so on. In our laboratory, we found that PXB has a significant anti-arrhythmic effect in animal experiments. Ligation of the left coronary artery ligation, aconitine induced arrhythmia inhibition was significantly greater than lidocaine. This article studies the effect of PXB on ventricular action potential in order to investigate its anti-arrhythmic mechanism.