目的 :研究苯妥英对缺氧大鼠大脑皮质神经元钙激活钾 [K(Ca) ]通道的影响。方法 :应用膜片钳单通道技术记录苯妥英对缺氧大鼠大脑皮质神经元上K(Ca)通道电流活动。电流信号经放大、滤波及转换后输入微机进行采样、储存和分析。结果 :苯妥英对缺氧大脑皮质神经元K(Ca)通道具有明显的激活作用 ,主要是增加通道的开放概率 (openprobability,Po)。结论 :苯妥英激活大脑皮质神经元K(Ca)通道 ,产生超极化电位 ,从而稳定细胞膜 ,降低细胞兴奋性 ,延缓缺氧除极的发生 ,这可能是苯妥英抗缺血脑损伤的另一个重要机制 Objective: To investigate the effect of phenytoin on calcium-activated potassium (K (Ca)) channel in cerebral cortex of hypoxic rats. Methods: Patch clamp technique was used to record K (Ca) channel current activity of phenytoin on cortical neurons in hypoxic rats. The current signal is amplified, filtered and converted into the computer for sampling, storage and analysis. RESULTS: Phenytoin had obvious activation on K (Ca) channel of hypoxic cortex neurons, mainly increasing open channel probability (Po). CONCLUSION: Phenytoin can activate K (Ca) channels in cerebral cortex neurons to produce hyperpolarization potentials to stabilize the cell membrane, reduce cell excitability and delay the occurrence of anoxia and depolarization, which may be another important role of phenytoin in preventing ischemic brain damage mechanism