过刊浏览

低浓度双氢哇巴因对豚鼠心室肌细胞内游离钙浓度的影响

尹京湘, 王永利, 李清, 尚忠林, 苏素文

河北医科大学基础医学研究所药理室.河北,石家庄 050017

摘要

用激光共聚焦显微镜检查研究低浓度双氢哇巴因(DHO)对豚鼠心室肌细胞内钙浓度([Ca~(2+)]_(i))的影响。DHO 1fmol/L-1mmol/L可增加心室肌细胞的[Ca~(2+)]_(i),尤其以10pmol/L DHO为显著。Nisoldipine、EGTA或TTX可分别部分抑制10pmol/L DHO的作用。去除胞外K~(+)和Na~(+)后,上述作用仍存在。以上结果表明,低浓度DHO可通过激活钙通道的TTX敏感的钠通道,或许还可直接促进胞内钙释放来增加[Ca~(2+)]_(i),并有不依赖Na~(+)/K~(+)泵而升高[Ca~(2+)]_(i)的作用。

关键词： 双氢哇巴因(DHO); 细胞内钙; 钠/钾泵; 豚鼠; 心肌细胞; 激光共聚焦显微术; 荧光染料

Effects of low concentration of dihydroouabain on intracellular calcium in guinea pig ventricular myocytes

Yin Jingxiang, Wang Yongli, Li Qing, Shang Zhonglin, Su Suwen

Department ofo Pharmacology,Institute of Basic Medicine,Hebei Medical University.Shijiazhuang 050017,Hebei

Abstract

The effects of low concentration of dihydroouabain (DHO) on intracellular calcium concentration ([Ca~(2+)]_(i)) were investigated in guinea pig ventricular myocytes. [Ca~(2+)]_(i) was detected by confocal microscopy and represented by fluorescent intensity. DHO (1 fmol/L-1mmol/L) increased [Ca~(2+)]_(i), especially at 10 pmol/L. Nisoldipine, egtazic acid, or tetrodotoxin partially inhibited the effect of 10 pmol/L DHO on [Ca~(2+]]_(i). The effects of DHO remained in the absence of extracellular K~(+) and Na~(+). These results suggest that low concentration of DHO might increase [Ca~(2+]_(i) via the receptor-operated Ca~(2+) channels, TTX-sensitive Na~(+) channels or/and triggering of intracellular calcium release; Na~(+)/K~(+) pump and Na~(+)/Ca~(2+) exchange seem not involved in the effect of DHO.

Key words: Dihydroouabain(DHO);Intracellular calcium;Ion pumps;Guinea pigs;Ventricular myocytes;Confocal microscopy;Fluorescent dyes

收稿日期：　　录用日期：

通讯作者：　　E-mail:

引用本文：

尹京湘, 王永利, 李清, 尚忠林, 苏素文. 低浓度双氢哇巴因对豚鼠心室肌细胞内游离钙浓度的影响[J]. 生理学报 2002; 54 (5): .

Yin Jingxiang, Wang Yongli, Li Qing, Shang Zhonglin, Su Suwen. Effects of low concentration of dihydroouabain on intracellular calcium in guinea pig ventricular myocytes. Acta Physiol Sin 2002; 54 (5): (in Chinese with English abstract).