CAJ | 학술논문

目的：通过圆窗龛局部给予特异性N R2B受体阻滞剂艾芬地尔，探讨其拮抗水杨酸钠致豚鼠螺旋神经节细胞损伤的作用。方法将ABR阈值小于40 dB SPL的健康花色豚鼠48只随机分为4组，每组12只，Ⅰ组为空白对照组；Ⅱ组为人工外淋巴液（artificial perilymph ，APL）组，左耳圆窗龛注人 APL 60μl；Ⅲ组为水杨酸钠组，左耳圆窗龛注入A PL 60μl ，腹腔注射水杨酸钠；IV组为艾芬地尔组，左耳圆窗龛注入溶于 A PL的艾芬地尔（10μmol/L ）60μl后，腹腔注射水杨酸钠。水杨酸钠注射量为400 mg · kg -1· d-1，连续注射7天。停药并行ABR测试后将动物处死，取出左侧耳蜗，每组随机取6只动物进行免疫组织化学染色观察耳蜗螺旋神经节（SGN ） caspase-3表达情况，6只行原位末端转移酶标记技术（terminal deoxynucleotidyl transferase -mediated dUTP -biotin nick end labeling assay ，TUNEL）法检测螺旋神经节细胞凋亡率。结果给药后，I、II、III、IV 组动物左耳ABR反应阈分别为31．67±5．16、33．33±5．17、64．17±7．36、49．17±5．85 dB SPL ；免疫组织化学染色显示，Ⅰ、Ⅱ组螺旋神经节细胞中caspase-3的表达量差异无统计学意义，Ⅲ、IV组螺旋神经节细胞中caspase-3的表达量较Ⅰ、Ⅱ组显著增高（P＜0．01），IV组螺旋神经节细胞中caspase-3的表达量较Ⅲ组明显降低（P＜0．01）。TUNEL法检测结果示，Ⅰ、Ⅱ组SGN细胞凋亡率无显著差异，Ⅲ、IV组SGN细胞凋亡率较Ⅰ、Ⅱ组显著增高（P＜0．01）， IV组SGN细胞凋亡率较Ⅲ组明显降低（P＜0．01）。结论耳蜗局部特异性阻断NR2B受体可以拮抗水杨酸钠致豚鼠螺旋神经节细胞的损伤。
목적：통과원창감국부급여특이성N R2B수체조체제애분지이，탐토기길항수양산납치돈서라선신경절세포손상적작용。방법장ABR역치소우40 dB SPL적건강화색돈서48지수궤분위4조，매조12지，Ⅰ조위공백대조조；Ⅱ조위인공외림파액（artificial perilymph ，APL）조，좌이원창감주인 APL 60μl；Ⅲ조위수양산납조，좌이원창감주입A PL 60μl ，복강주사수양산납；IV조위애분지이조，좌이원창감주입용우 A PL적애분지이（10μmol/L ）60μl후，복강주사수양산납。수양산납주사량위400 mg · kg -1· d-1，련속주사7천。정약병행ABR측시후장동물처사，취출좌측이와，매조수궤취6지동물진행면역조직화학염색관찰이와라선신경절（SGN ） caspase-3표체정황，6지행원위말단전이매표기기술（terminal deoxynucleotidyl transferase -mediated dUTP -biotin nick end labeling assay ，TUNEL）법검측라선신경절세포조망솔。결과급약후，I、II、III、IV 조동물좌이ABR반응역분별위31．67±5．16、33．33±5．17、64．17±7．36、49．17±5．85 dB SPL ；면역조직화학염색현시，Ⅰ、Ⅱ조라선신경절세포중caspase-3적표체량차이무통계학의의，Ⅲ、IV조라선신경절세포중caspase-3적표체량교Ⅰ、Ⅱ조현저증고（P＜0．01），IV조라선신경절세포중caspase-3적표체량교Ⅲ조명현강저（P＜0．01）。TUNEL법검측결과시，Ⅰ、Ⅱ조SGN세포조망솔무현저차이，Ⅲ、IV조SGN세포조망솔교Ⅰ、Ⅱ조현저증고（P＜0．01）， IV조SGN세포조망솔교Ⅲ조명현강저（P＜0．01）。결론이와국부특이성조단NR2B수체가이길항수양산납치돈서라선신경절세포적손상。
Objective To investigate whether blocking NR2B receptor can reverse the process of cytotoxicity to spiral ganglion neurons induced by sodium salicylate in guinea pig by applying ifenprodil (a NR2B antagonist) at the round window niche .Methods Sixty healthy guinea pigs provided by the experimental animal center of Guangxi medical university were randomly and evenly divided into a control group (Group I ,no treatment) ,an APL group (Group II ,60μl APL directly applied to the round window ) ,a sodium salicylate group (Group III ,60 μl APL di-rectly applied to the round window and then be given intraperitoneal sodium salicylate injection ) ,and an ifenprodil group (Group IV ,60μl of 10μmol/l ifenprodil in APL directly applied to the round window and then be given intra-peritoneal sodium salicylate injection ) .Sodium salicylate was given at 400 mg · kg -1 · d-1 for 7 days .Auditory brainstem responses (ABRs) were recorded before animal sacrifice by decapitation .The left cochlea was removed and prepared for detection of caspase -3 expression in spiral ganglion neurons via immunohistochemistry .From each group ,6 cochleae were used to test apoptosis index in spiral ganglion neurons using the TUNEL technique .Results Before salicylate administration ,the ABR threshold was less than 40 dB SPL in all animals .After salicylate ad-ministration ,the ABR threshold was 33 .33 ± 5 .17 dB SPL in Group II ,64 .17 ± 7 .36 dB SPL in Group III and 49 .17 ± 5 .85 dB SPL in Group IV ,in contrast to 31 .67 ± 5 .16 dB SPL in Group I (controls) .The caspase -3 ex-pression was not changed obviously in Group I and Group II ,but was significantly changed in Group III and Group IV (P<0 .01) .The caspase-3 expression appeared to be decreased in Group IV compared to those in Groups III (P<0 .05) ,but still increased compared to those of in Group I and II (P<0 .05) .The apoptosis index among spiral ganglion neurons in Groups III and IV increased significantly compared to those of in Group I and II (P<0 .001) .It was however ,lower in Group IV than in Group III (P<0 .01) .Conclusion Blocking NR2B receptor with specificity can reverse the process of cytotoxicity to spiral ganglion neurons induced by sodium salicylate in guinea pig .