EFFECTS OF PROTON BUFFERING AND OF AMILORIDE DERIVATIVES ON REPERFUSION ARRHYTHMIAS IN ISOLATED RAT HEARTS - POSSIBLE EVIDENCE FOR AN ARRHYTHMOGENIC ROLE OF NA+-H+ EXCHANGE

被引：123

作者：

DENNIS, SC ^{[1
]}

COETZEE, WA ^{[1
]}

CRAGOE, EJ ^{[1
]}

OPIE, LH ^{[1
]}

机构：

[1] UNIV CAPE TOWN, SCH MED, ISCHEM HEART DIS RES UNIT, CAPE TOWN 7925, SOUTH AFRICA

来源：

CIRCULATION RESEARCH | 1990年 / 66卷 / 04期

关键词：

Na[!sup]+[!/sup]-Ca[!sup]2+[!/sup] exchange; Na[!sup]+[!/sup]-H[!sup]+[!/sup] exchange; reperfusion arrhythmias;

D O I：

10.1161/01.RES.66.4.1156

中图分类号：

R5 [内科学];

学科分类号：

1002 [临床医学]; 100201 [内科学];

摘要：

We investigated the hypothesis that an accelerated Na+(o)-H+(i) exchange on reperfusion may lead to a displacement of the 3[Na+] [Ca2+](i/o) equilibrium in favor of an arrhythmogenic rise in cytosolic [Ca2+]. Supporting evidence was obtained by subjection of isolated rat hearts to 15 minutes of low-flow (5% of control) ischemia and 2 minutes of reperfusion in the presence of a Krebs-Henseleit HEPES buffer (pH 7.4) containing lactate (10 mM). At first, the [HEPES] was fixed at 5 mM; then, 2 minutes before reflow, either the [HEPES] was varied from 50 to 1 mM to slow H+(o) washout, or increasing concentrations of 5-(N,N-dimethyl)-amiloride (K(i) 7 μM) or 5-(N,N-hexamethylene)-amiloride (K(i) 0.2 μM) were added for inhibition of Na+-H+ exchange. In each case, reperfusion ventricular arrhythmias were reduced by 69-73% (p<0.001).

引用

页码：1156 / 1159

页数：4

共 20 条

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INTRACELLULAR PH AND SURFACE PH IN SKELETAL AND CARDIAC-MUSCLE MEASURED WITH A DOUBLE-BARRELLED PH MICROELECTRODE [J].