多胺对心脏跨膜电位和电流的修饰作用。

Modification of the cardiac transmembrane potentials and currents by polyamines.

作者信息

Kecskemeti V, Kelemen K, Marko R, Selmeci L

机构信息

Department of Pharmacology, Semmelweis University of Medicine, Budapest, Hungary.

出版信息

Eur J Pharmacol. 1987 Oct 13;142(2):297-303. doi: 10.1016/0014-2999(87)90119-1.

DOI:10.1016/0014-2999(87)90119-1

PMID:3691643

Abstract

Spermine up to 10(-5) M increased the resting potential (RP) and maximum rate of rise (Vmax) of the action potential (AP) and accelerated the initial (20, 50%) repolarization in isolated guinea-pig and cat atria. These effects were not modified by pindolol (4 X 10(-7) M) or atropine (3 X 10(-7) M) but were prevented by indomethacin (10(-6) M). The right papillary muscle of guinea-pig only showed the acceleration of repolarization while the other parameters were not changed. Spermine did not influence the inward membrane currents under voltage clamp conditions in frog sinoatrial fibers. Spermidine up to 10(-5) M increased RP, Vmax and the duration of AP in guinea pig papillary muscle. RP, Vmax and AP duration were moderately enhanced by spermidine in guinea pig atrium and were not changed in cat atrium. Spermidine was found to stimulate the inward membrane current. Its stimulatory effect was confined to the fast component of the inward current. Neither spermidine nor spermine were able to induce the Ca2+-dependent slow AP in 25 mM K+-depolarized atrium. It is suggested that polyamines influence cardiac membrane events which are responsible for AP and ionic currents.

摘要

高达10⁻⁵ M的精胺可增加豚鼠和猫离体心房的静息电位（RP）和动作电位（AP）的最大上升速率（Vmax），并加速初始（20%、50%）复极化。这些效应不受吲哚洛尔（4×10⁻⁷ M）或阿托品（3×10⁻⁷ M）的影响，但可被吲哚美辛（10⁻⁶ M）阻断。豚鼠右乳头肌仅表现出复极化加速，而其他参数未改变。在电压钳制条件下，精胺对蛙窦房结纤维的内向膜电流无影响。高达10⁻⁵ M的亚精胺可增加豚鼠乳头肌的RP、Vmax和AP持续时间。在豚鼠心房中，亚精胺可适度增强RP、Vmax和AP持续时间，而在猫心房中则无变化。发现亚精胺可刺激内向膜电流。其刺激作用仅限于内向电流的快速成分。在25 mM K⁺去极化的心房中，亚精胺和精胺均不能诱导Ca²⁺依赖性慢动作电位。提示多胺影响负责动作电位和离子电流的心脏膜事件。