摘要
目的:探讨大鼠心室肌细胞肿胀激活内向整流阳离子流I_(Cir,swell)与低渗性肿胀时体积的关系及对牵张活化离子通道阻断剂Gd^(3+)的敏感性。方法:①采用图文采集及分析系统测量并比较大鼠心室肌细胞在等渗(1T)及低渗(0.6T)溶液中体积的变化。②采用全细胞电压钳方式记录大鼠心室肌细胞在1T及0.6T溶液中I_(Cir,swell)的变化。结果:①大鼠心室肌细胞在0.6T溶液中比1T溶液中体积分别增加37.4％和35.9％。②正常细胞在1T溶液中未见电流激活,在0.6T溶液中的细胞肿胀使内向及外向电流同时增大,其内向电流在-100mV电压刺激时的电流强度由1T溶液的-1.55±0.23pA/pF增大至0.6T溶液中的-6.45±1.03pA/pF(P<0.01),并能被10μM Gd^(3+)抑制。结论:心肌细胞低渗性肿胀可激活牵张活化电流I_(Cir,swell),且可被Gd^(3+)抑制,I_(Cir,swell)可能在机械-电反馈导致心律失常的过程中起重要作用。
objective: To explore the changes of swelling- activated ion currents ICir,swell in mechanoelectric conduction. Methods:①The image acquiring and analysis system was used to determine the changes of the volume of the rats myocytes in iso-tonic and hypotonic solution. ②The currents elicited by swelling in solution with 0.6× normal osmolarity ,namely ICir,swell, were studied using patch clamp techniques with whole- cell voltage clamp configuration. Resultes:①The volume of the ventricular my-ocytes increased in 0,6T media by 37 .4% and 35 .9% , respectively. ②Cell swelling in 0.6T solution caused activation of an large inwardly rectifying at negative potentials increased in amplitude, at -100mV from - 1.55±0 .23pA/pF to - 6.45±1 .03pA/pF (P<0.01) which was blocked by 10μM Gd3+ . Conclusion: ① Osmotic cell swelling of rat ventricular myocytes activated cation stretch/swelling activated channels-ICir,swell, which could be blocked Cd3 + .② The stretch - activated ICir,swell may take an important role in stretch induced arrhythmia.
出处
《农垦医学》
2003年第5期313-315,共3页
Journal of Nongken Medicine
