摘要
[目的 ]研究大鼠海马神经元去极化激活的外向钾电流的特征 ,并在此基础上初步探讨SO2 衍生物对此外向电流的影响。 [方法 ]利用全细胞膜片钳技术。 [结果 ]短时去极化至 -60mV以上电位可引发快速上升的外向电流 ,之后缓慢衰减至一平台。当保持电位改变时 ,该峰电流与平台电流的幅度均会发生变化 ,但前者较后者变化显著。试验中测得峰电流与平台电流的翻转电位分别为 (-76 1± 5 97)mV和 (-83 6± 4 13 )mV ,与用Nerst方程计算出的本试验细胞外液与电极内液的钾离子平衡电位EK=-88mV接近 ,说明该外向电流是钾电流 ,且提示此外向电流包括两种成分 ,即峰电流IA 和平台电流IK。SO2 衍生物可剂量依赖地增大此两种成分的外向钾电流 ,使二者增大 5 0 %的SO2 衍生物剂量分别为 2 6 19μmol/L和 14 5 0 μmol/L。[结论 ]大气SO2 污染可能与一些中枢神经系统疾病的发生以及衰老有关。
To study the characteristics of outward K + currents activated by depolarizing test pulses in hippocampal neurons in rats and the effects of SO 2 derivatives on the outward currents. The whole cell patch clamp techniques were used. Depolarizing test pulse to -60 mV activated rapidly ascending outward currents,then descending slowly to a plateau. When holding potentials changed,peak and plateau currents both changed,but the change in peak current was more obvious. Their reversal potentials were -76 1±5 97 mV and -83 6±4 13 mV. It was confirmed that the outward currents were K + currents and the outward currents included two components(I A and I K). SO 2 derivatives could increase I A and I K in a dose dependent manner,and the doses of 50% increment were 26 19 μmol/L and 14 50 μmol/L,respectively. [Conclusion] SO 2 pollution in atmosphere might be related to some diseases of central neurve system.
出处
《环境与职业医学》
CAS
北大核心
2003年第1期1-5,共5页
Journal of Environmental and Occupational Medicine
基金
国家自然科学基金资助项目 (编号 :30 0 70 647)
