CIRCUMSTANTIAL EVIDENCE FOR INCREASED POTASSIUM CONDUCTANCE OF MEMBRANE OF CARDIAC-MUSCLE BY 2-NICOTINAMIDOETHYL NITRATE (SG-75)

被引：65

作者：

YANAGISAWA, T

SATOH, K

TAIRA, N

机构：

[1] Department of Pharmacology, Tohoku University School of Medicine

来源：

JAPANESE JOURNAL OF PHARMACOLOGY | 1979年 / 29卷 / 05期

关键词：

D O I：

10.1254/jjp.29.687

中图分类号：

R9 [药学];

学科分类号：

1007 ;

摘要：

The mechanism of action of 2-nicotinamidoethyl nitrate (SG-75), was investigated by the use of arterially blood-perfused papillary muscle preparations of the dog. All drugs were administered intra-arterially. SG-75 shortened the effective refractory period (ERP) and decreased the rate of automaticity and developed tension of the papillary muscle, whereas verapamil failed to change the ERP despite a decrease in the developed tension. SG-75 in extremely high doses induced ventricular fibrillation. Methacholine produced decreases in the rate of automaticity and developed tension, and the actions were abolished by atropine. The SG-75-induced decreases in two parameters were not modified by atropine. These results indicate that the cardiac action of SG-75 differs from that of calcium-antagonistic vasodilators and it is suggested that the basic mechanism of action of SG-75 involves an increase in potassium con ductance in the membrane of cardiac muscle, without mediation through muscarinic receptors. © 1979, The Japanese Pharmacological Society. All rights reserved.

引用

页码：687 / 694

页数：8

共 19 条

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