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本研究探讨水杨酸钠对小鼠下丘核神经元γ- 氨基丁酸(γ-aminobutyricacid, GABA)、谷氨酸(glutamate, Glu)表达及听反应的影响。36 只成年健康昆明小鼠分为三组(每组12 只): 对照组；NaSA 组(水杨酸钠给药每天450 mg/kg); NaSA +lidocaine 组(水杨酸钠给药每天450 mg/kg + 利多卡因给药每天10 mg/kg)。各组均经腹腔注射给药，对照组给以同等剂量的生理盐水。给药15 d 后，免疫组织化学方法检测下丘核区神经元GABA、Glu 的表达；细胞外电生理记录技术观察下丘核区神经元强度- 发放率函数、强度- 潜伏期函数和频率- 调谐曲线的变化。结果如下：(1) NaSA 组与NaSA + lidocaine 组GABA 表达明显较对照组降低，但该两组比较无显著性差异；NaSA 组Glu 表达较对照组和NaSA + lidocaine 组明显增加，NaSA + lidocaine 组与对照组比较无显著性差异。 (2) NaSA组强度- 发放率函数呈低强度时上移，高强度时下降的非单调性改变；强度- 潜伏期函数下移；调谐曲线从狭窄型向宽阔型转变。 (3) NaSA + lidocaine 给药后强度- 发放率函数无非单调性改变现象，强度- 潜伏期函数下移的程度较NaSA 组明显减轻，而神经元的调谐曲线从狭窄型向宽阔型转变例数也显著减少。以上结果提示：水杨酸钠能增强Glu 阳性神经元表达，但抑制GABA 阳性神经元表达；水杨酸钠可影响下丘核神经元的听反应特性，强度- 发放率函数呈非单调性变化，强度- 潜伏期函数下移，调谐曲线尖部变宽。利多卡因有逆转水杨酸钠改变下丘核神经元听反应的作用。

The effects of sodium salicylate (NaSA) on the expressions of γ-aminobutyricacid (GABA) and glutamate (Glu), andauditory response properties of the inferior colliculus neurons in mice were studied. Thirty-six Kunming mice were divided into threegroups: control group (saline injection); NaSA group (NaSA 450 mg/kg, i.p., each day for 15 d); NaSA + lidocaine group (NaSA 450 mg/kg + lidocaine 10 mg/kg, i.p., each day for 15 d). The expressions of GABA and Glu were examined with immunohistochemical method.The intensity-rate function, intensity-latency function and frequency-tuning curve were determined with extracellular electrophysiologicalrecording. Results are as follows: (1) The expression of GABA in the NaSA and NaSA + lidocaine groups decreased remarkablycompared with that in the control group; there was no noticeable difference between the NaSA and NaSA + lidocaine groups. Theexpression of Glu in the NaSA group increased significantly compared with that in the control and NaSA + lidocaine groups. Nodifference in the expression of Glu was found between the control and NaSA + lidocaine groups. (2) In NaSA group, the intensity-rate function displayed a non-monotonic pattern, rising at low intensity and descending at high intensity; the tip of frequency-tuning curvesbecame broad after administration of NaSA. (3) The changes in intensity-rate function and intensity-latency function were not evidentand the tips of the frequency-tuning curves sharpened in the NaSA+lidocaine group. These results suggest that administration of NaSAincreases the expression of Glu-positive neurons and reduces that of GABA-positive neurons in the inferior colliculus. NaSA changesthe auditory response properties of the inferior colliculus and lidocaine can reverse these changes.