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为研究急性分离大鼠皮层神经元上ＡＴＰ敏感钾通道的特性，本实验采用了膜片钳技术之膜内面向外记录方法。ＡＴＰ敏感钾通道电导为２００ｐＳ左右，翻转电位为０ｍＶ，有外向整流现象；通道开放常呈簇状猝发样开放，平均开放时间和开放概率随去极化程度增大而增加，随超极化程度增大而减少；低浓度ＡＴＰ有促进通道开放作用，并可激活二级电流；高浓度ＡＴＰ抑制通道开放概率并随浓度增大而增强；ＡＴＰ浓度增高到１或２ｍｍｏｌ／Ｌ时，通道电流被阻断。０.１ｍｍｏｌ／Ｌ优降糖可立即抑制通道活动。急性分离的皮层神经元上ＡＴＰ敏感钾通道特性与培养神经元有差别；低浓度ＡＴＰ可激活ＡＴＰ敏感钾通道，防止神经细胞过度兴奋，从而起到保护脑缺血缺氧损伤的作用。
In order to study the characteristics of ATP-sensitive potassium channels in acutely isolated rat cortical neurons, a patch-clamp technique was used to record the outwards of the membrane surface. The conductance of ATP-sensitive potassium channel was about 200 pS, and the reversal potential was 0 mV, with outward rectification. The open channel often showed cluster-like burst-like opening, the average open time and open probability increased with the degree of depolarization, Increased and decreased; low concentration of ATP can promote the opening of the channel, and can activate the secondary current; high concentration of ATP inhibition of open channel probability increases with increasing concentration; ATP concentration increased to 1 or 2mmol / L, the channel current is Blocked. 0.1 mmol / L of glyburide can immediately inhibit channel activity. Acutely isolated cortical neurons of ATP-sensitive potassium channel characteristics and cultured neurons are different; low concentrations of ATP can activate ATP-sensitive potassium channels, to prevent nerve cells over-excitement, which play a protective effect of cerebral ischemia and hypoxia injury.