摘要
目的 :解释治疗水平 (低浓度 )强心甙的正性肌力作用。方法 :用全细胞膜片钳技术 ,在分离的豚鼠心室肌细胞观察到双氢哇巴因 (DHO)对 Na+/ K+泵电流 (Ip )的激活作用。结果 :DHO在 10 - 8～ 10 - 1 0 m ol· L- 1范围内可增加外向电流。当从细胞外液去除 K+或从电极内液去除 Na+或胞内应用 vanadate抑制了 Ip后 ,外向电流消失。结论 :DHO可使 Na+/ K+泵兴奋 ,产生了外向泵电流。Ip激活是低浓度强心甙对心脏 Na+/ K+泵的直接作用。
AIM:To explain the positive inotropic action of glycosides at therapeutic levels. METHODS: Using the whole-cell patch clamp technique, we studied the effects of low concentration dihydrooubain (DHO) on Na +/K + pump current (Ip) in isolated guinea pig ventricular myocytes. RESULTS: An increase in the outward current was observed with DHO concentrations ranging from 10 -10 to 10 -8 mol·L -1. The increase did not occur when Ip was blocked by the removal of either external K + or intracellular Na +, or by the addition of intracellular vanadate. CONCLUSION: DHO could stimulate Na +/K + pump, and generate the outward pump current. The stimulation of Ip is a direct action of low concentration glycosides on the cardiac Na +/K + pump.
出处
《心脏杂志》
CAS
2003年第4期300-302,共3页
Chinese Heart Journal
基金
河北省自然科学基金资助 (No 30 136 0 )
