CAJ | 학술논문

目的观察神经病理性疼痛大鼠背根神经节(DRG)神经元中兴奋性氨基酸转运蛋白3(EAAT3)的分布特征和表达变化.方法 SD雄性大鼠50只,随机分为对照组、假手术组、坐骨神经慢性缩窄性损伤模型(CCI)组(3、7、14d组).所有大鼠行热、机械痛觉过敏痛觉阈值测试完成后用免疫荧光和免疫印迹技术检测EAAT3的分布特征及蛋白表达水平.结果 (1)与对照组和假手术组比较,CCI组大鼠术后3d开始直至术后14 d均出现明显的机械、热痛觉过敏(P＜0.05).(2)对照组大鼠DRG中EAAT3均匀分布于中小直径神经元的胞质和胞膜,平均荧光强度为17.88±1.57.CCI术后7、14 d EAAT3从胞质向胞膜转移,平均荧光强度分别降至13.94±1.75、14.55±1.43；两组EAAT3蛋白表达水平也比对照组明显下降(P＜0.05).结论 CCI组大鼠DRG中EAAT3的蛋白表达水平和分布改变与大鼠疼痛行为学改变在时相上基本一致,外周初级感觉神经元中EAAT3分布及表达变化可能参与神经病理性疼痛的发生和发展过程.
목적 관찰신경병이성동통대서배근신경절(DRG)신경원중흥강성안기산전운단백3(EAAT3)적분포특정화표체변화.방법 SD웅성대서50지,수궤분위대조조、가수술조、좌골신경만성축착성손상모형(CCI)조(3、7、14d조).소유대서행열、궤계통각과민통각역치측시완성후용면역형광화면역인적기술검측EAAT3적분포특정급단백표체수평.결과 (1)여대조조화가수술조비교,CCI조대서술후3d개시직지술후14 d균출현명현적궤계、열통각과민(P＜0.05).(2)대조조대서DRG중EAAT3균균분포우중소직경신경원적포질화포막,평균형광강도위17.88±1.57.CCI술후7、14 d EAAT3종포질향포막전이,평균형광강도분별강지13.94±1.75、14.55±1.43；량조EAAT3단백표체수평야비대조조명현하강(P＜0.05).결론 CCI조대서DRG중EAAT3적단백표체수평화분포개변여대서동통행위학개변재시상상기본일치,외주초급감각신경원중EAAT3분포급표체변화가능삼여신경병이성동통적발생화발전과정.
Objective To explore the distribution and expression changes of excitatory amino acid transporter 3 (EAAT3) in the dorsal root ganglion (DRG) neurons of neuropathic pain rats.Methods Fifty adult male SD rats were randomly allocated to eontrol group,sham operation group,and 3-,7-and 14-day groups after chronic constriction injury (CCI).Thermal and mechanical nociceptive thresholds were assessed in all animals.All the animals were killed,and the L5 DRG was removed for analysis of the EAAT3-immunoreactive (EAAT3-IR) neurons and the protein expression of EAAT3 by using immunofluorescence and Western blotting respectively.Results (1) CCI,but not sham surgery,produced significant mechanical allodynia and thermal hyperalgesia (P ＜ 0.05) ; (2) EAAT3-IR neurons in DRG of control group were mostly small-and medium-sized,and EAAT3 was well-distributed in the cytoplasm and cytomembrane.The EAAT3 was redistributed and transferred from cytoplasm to cytomembrane at 7th,and 14th day after CCI,and both the mean intensity of fluorescence of EAAT3-IR and the protein expression were reduced significantly at 7th,and 14th day after CCI (P ＜0.05).Conclusion The expression reduction of EAAT3 in DRG was accompanied by changes of pain behavior of CCI rat,suggesting that the reduction of EAAT3 is related to peripheral noxious stimulation.The changes of expression and distribution of EAAT3 in peripheral primary sensory neurons may be contributed to the occurrence and maintenance of neuropathic pain.