水杨酸钠对小鼠下丘核神经元γ-氨基丁酸和谷氨酸表达及听反应特性的影响  

Effects of sodium salicylate on the expressions of γ-aminobutyricacid and glutamate and auditory response properties of the inferior colliculus neurons in mice

作　　者：尹时华[1] 唐安洲[1] 幸小玲[2] 谭颂华[1] 谢利红[1] 

机构地区：[1]广西医科大学第一附属医院耳鼻咽喉科,南宁530021 [2]广西医科大学第一附属医院麻醉科,南宁530021

出　　处：《生理学报》2006年第5期449-455,共7页Acta Physiologica Sinica

基　　金：This work was supported by the Doctoral Start Foundation of Guangxi University of Medical Sciences (No. 304156) and theYouth Foundation of Hubei Province (No. 2003B002).

摘　　要：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450mg/kg);NaSA+lidocaine组(水杨酸钠给药每天450mg/kg+利多卡因给药每天10mg/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15d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）, and auditory response properties of the inferior colliculus neurons in mice were studied, Thirty-six Kunming mice were divided into three groups： 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 electrophysiological recording. Results are as follows： （1） The expression of GABA in the NaSA and NaSA ＋ lidocaine groups decreased remarkably compared with that in the control group; there was no noticeable difference between the NaSA and NaSA ＋ lidocaine groups, The expression of Glu in the NaSA group increased significantly compared with that in the control and NaSA ＋ lidocaine groups. No difference 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 curves became broad after administration of NASA. （3） The changes in intensity-rate function and intensity-latency function were not evident and the tips of the frequency-tuning curves sharpened in the NaSA＋lidocaine group. These results suggest that administration of NaSA increases the expression of Glu-positive neurons and reduces that of GABA-positive neurons in the inferior colliculus. NaSA changes the auditory response properties of the inferior colliculus and lidocaine can reverse these changes.

关 键 词：水杨酸钠 下丘核神经元 听反应 小鼠 

分 类 号：Q42[生物学—神经生物学]