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在培养的大鼠颈上神经节神经元上，用全细胞膜片钳技术记录γ－氨基丁酸（ＧＡＢＡ）所激活的通道电流。当膜电位钳制在－６０ｍＶ时，压力喷射ＧＡＢＡ２０μｍｏｌ／Ｌ引起的峰电流为７３６±４８４ｐＡ（ｎ＝３１）。对ＧＡＢＡ电流与膜电位的关系的分析表明，当膜电位钳制在正负水平时，ＧＡＢＡ分别引起外向及内向电流，但外向电流的斜率稍大于内向电流，即存在轻度外向整流。电流的反转电位接近０ｍＶ。为了确定ＧＡＢＡ受体通道对Ｃｌ－的通透性，观察了改变细胞内Ｃｌ－浓度对ＧＡＢＡ电流的反转电位的影响。结果发现，所测的反转电位与用Ｇｏｏｄｍａｎ—Ｈｏｄｇｋｉｎ—Ｋａｔｚ方程预测的结果相符，提示ＧＡＢＡ受体对Ｃｌ－具有选择通透性，可能属ＧＡＢＡＡ受体。
The channel currents activated by γ-aminobutyric acid (GABA) were recorded using whole-cell patch clamp techniques on cultured rat superior cervical ganglion neurons. When the membrane potential was clamped at -60 mV, the peak current induced by the pressure-sprayed GABA 20 μmol / L was 736 ± 484 pA (n = 31). The analysis of the relationship between GABA current and membrane potential shows that GABA induces both outward and inward currents when the membrane potential is clamped at positive and negative levels, but the slope of the outward current is slightly larger than the inward current, that is, there is a slight outward rectification. The reversal potential of the current is close to 0mV. In order to determine the GABA receptor channel permeability of Cl-, the effect of changing intracellular Cl-concentration on the reversal potential of GABA current was observed. The results showed that the measured inversion potential was in good agreement with the Goodman-Hodgkin-Katz equation, suggesting that the GABA receptor is selective for Cl- and may be a GABAA receptor.