水杨酸钠可逆性抑制耳蜗螺旋神经节神经元GABAa受体电流

摘要

Objective To study the effect of sodium salicylate (SS) on the function of GABAa receptors in spiral gangli⁃on neurons (SGNs). Methods GABAa receptor currents were recorded using whole-cell patch clamp techniques in isolated SGNs. The effects of SS were characterized. Results The currents evoked by GABA in SGNs were blocked by 10μM bicucul⁃line. No detectable currents were recorded upon using SS at 0.5 mM, 0.1 mM or 5 mM. Various degrees of reversible suppres⁃sions of GABA-induced currents were observed by administrating GABA (100μM or 500μM) combined with SS. Conclu⁃sion GABAa receptors currents can be recorded in rat cochlea SGNs. SS reversibly attenuates GABAa receptors response in SGNs. The effects are dose-dependent with both GABA and SS.%目的：探讨水杨酸钠对大鼠耳蜗螺旋神经节神经元（SGN）GABAa受体的作用。方法采用全细胞膜片钳记录技术，观察离体培养大鼠SGN的GABAa受体激活电流的特性及水杨酸钠对其作用特点。结果在SGN上可记录到GABAa受体激动剂GABA诱发的内向电流，该电流呈浓度依赖性且可被荷包牡丹碱所阻断；水杨酸钠作用在SGN上未诱出电流，100μM、500μM的GABA与不同浓度的水杨酸钠(500μM、1000μM、5000μM)分别联合作用时，GABA诱发的电流可被不同程度地抑制，且该抑制作用呈可逆性。结论大鼠SGN上可记录到GABAa受体电流，且水杨酸钠以浓度依赖的方式可逆性抑制GABAa受体电流，抑制作用与GABA浓度有关。