动作电位时程的病理性延长是链脲佐菌素诱导的糖尿病小鼠心肌中α-肾上腺素能受体介导的负性肌力降低的原因。

Pathological prolongation of action potential duration as a cause of the reduced alpha-adrenoceptor-mediated negative inotropy in streptozotocin-induced diabetic mice myocardium.

作者信息

Kanae Haruna, Hamaguchi Shogo, Wakasugi Yumi, Kusakabe Taichi, Kato Keisuke, Namekata Iyuki, Tanaka Hikaru

机构信息

Department of Pharmacology, Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba 274-8510, Japan.

出版信息

J Pharmacol Sci. 2017 Nov;135(3):131-133. doi: 10.1016/j.jphs.2017.10.005. Epub 2017 Oct 31.

DOI:10.1016/j.jphs.2017.10.005

PMID:29122532

Abstract

Effect of pathological prolongation of action potential duration on the α-adrenoceptor-mediated negative inotropy was studied in streptozotocin-induced diabetic mice myocardium. In streptozotocin-treated mouse ventricular myocardium, which had longer duration of action potential than that in control mice, the negative inotropic response induced by phenylephrine was smaller than that in control mice. 4-Aminopyridine prolonged the action potential duration and decreased the negative inotropy in control mice. Cromakalim shortened the action potential duration and increased the negative inotropy in streptozotocin-treated mice. These results suggest that the reduced α-adrenoceptor-mediated inotropy in the diabetic mouse myocardium is partly due to its prolonged action potential.

摘要

在链脲佐菌素诱导的糖尿病小鼠心肌中，研究了动作电位时程病理性延长对α-肾上腺素能受体介导的负性肌力作用的影响。在经链脲佐菌素处理的小鼠心室心肌中，其动作电位时程比对照小鼠更长，去氧肾上腺素诱导的负性肌力反应比对照小鼠更小。4-氨基吡啶延长了对照小鼠的动作电位时程并降低了负性肌力作用。克罗卡林缩短了经链脲佐菌素处理小鼠的动作电位时程并增强了负性肌力作用。这些结果表明，糖尿病小鼠心肌中α-肾上腺素能受体介导的肌力减弱部分归因于其延长的动作电位。