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目的：研究大鼠胃粘膜壁细胞基底膜氯通道电流的电生理特性、调节因素及其在壁细胞生理活动中的作用．方法：全细胞膜片钳记录法．结果：壁细胞的基底膜上记录到一种非电压、非时间依赖性氯通道电流．当细胞外液氯离子浓度由１４２ｍｍｏｌ／Ｌ降为２０ｍｍｏｌ／Ｌ时，电流的反转电位发生相应偏移（由－１．２ｍＶ右移至３０ｍＶ）．其阴离子选择性为Ｉ－＞Ｂｒ－＞Ｃｌ－＞Ｆ－．细胞外液ｐＨ值由７．４降至４．０时此电流幅度减小，抑制率为（４６．５±７．４）％，而ｐＨ增高对电流无影响．向细胞外液中加入ｈｉｓｔａｍｉｎｅ，ａｃｅｔｙｌｃｈｏｌｉｎｅ，ｉｎ－ｄｏｍｅｔｈａｃｉｎ及ｖｅｒａｐａｍｉｌ均不影响此电流．结论：在大鼠胃粘膜壁细胞基底膜上存在一种非电压、非时间依赖性氯通道电流，此氯通道与细胞静息膜电位的维持密切相关，可能是一种本底通道或称为看家通道
OBJECTIVE: To study the electrophysiological characteristics, regulatory factors and their roles in the parietal cell physiological activities of rat gastric mucosa parietal cells. Methods: Whole-cell patch-clamp recording method. RESULTS: A non-voltage, non-time-dependent chloride channel current was recorded on parietal cells. When the extracellular solution of chloride ion concentration from 142mmol / L to 20mmol / L, the current reversal potential shift (-1.2mV right to 30mV). Its anion selectivity is I-> Br-> Cl-> F-. When the extracellular pH value decreased from 7.4 to 4.0, the amplitude of this current decreased and the inhibition rate was (46.5 ± 7.4)%, while the increase of pH had no effect on the current. The addition of histamine, acetylcholine, in-domethacin and verapamil to the extracellular fluid did not affect this current. CONCLUSION: There is a non-voltage-dependent and time-dependent chloride channel current in the basement membrane of rat gastric mucosa parietal cells. This chloride channel is closely related to the maintenance of resting membrane potential of the cells and may be a background channel or Housekeeping channel