摘要:
Objective To observe the effect of spinal cord stimulation on expression of spinal GLT-1 and GLAST in rats with diabetic neuropatbic pain.Methods Forty-eight healthy male SD rats,only 2 months old,weighting 250-300 g,using the random number table method,were divided into four groups (n=12):the control group (group C),diabetes neuralgia group (group D),false stimulation group (group N)and spinal cord stimulation group (group S).The model of diabetes was induced by the pedtoneal injec-tion of streptozocin (STZ),electrodes were placed into the epidural space 1 9 days after injection of STZ in groups N and S,in addition,group S was performed 26-28 days after injection of STZ.Mechanical contrac-tion leg threshold (MWT)were determined one day before STZ injection,2 d,7 d,14 d and 28 d after STZ injection.The rats were sacrificed,the lumbar spinal cord tissue were obtained for determination of GLT-1 and GLAST expression in spinal cord tissues on 28 d after measurement of MWT.Results Compared with group C,MWT was decreased 14 d and 28 d after STZ injection,and expression levels of GLT-1 and GLAST mRNA were increased on 14 d and 28 d (P<0.05);Compared with before STZ injection,MWT of group D,group N and group S was decreased on 14 d and 28 d (P<0.05);Compared with group D, MWT was increased,and expression levels of GLT-1 and GLAST mRNA were increased in group S on 28 d after STZ injection (P<0.05 ).Conclusion The mechanism of spinal cord stimulation reducing rats diabetes neuralgia may be related to elevating the expression of GLT-1 and GLAST.%目的 观察脊髓电刺激对糖尿病大鼠痛性周围神经病变时脊髓胶质细胞谷氨酸转运体-1(GLT-1)和谷氨酸-天冬氨酸转运体(GLAST)表达的影响.方法 选择健康雄性 SD 大鼠 48只,2 月龄,体重 250~300 g,采用随机数字表法将其分为四组:对照组(C 组)、糖尿病神经痛组(D组)、假刺激组(N组)和脊髓电刺激组(S 组),每组 1 2 只.D、N 和 S 组腹腔注射 1 %链脲佐菌素 60 mg/kg制备大鼠糖尿病痛性周围神经病变模型,C组注射等容量枸橼酸-枸橼酸钠缓冲液.N 组和 S组于造模后19 d在硬膜外间隙置入电极,S组于造模后26~28 d行脊髓电刺激.于造模前1 d、造模后 2、7、14、28 d测定机械缩足反应阈(MWT).于造模后 28 d测定痛阈后处死大鼠,取 L4~5脊髓组织,采用荧光定量PCR法和 Western blot法检测脊髓背角 GLT-1 和 GLAST mRNA表达量和蛋白含量.结果 与C组比较,造模后 14、28 d D组、N组和 S组 MWT明显降低(P<0.05);造模后 28 d S组胶质细胞 GLT-1 及 GLAST mRNA表达量和蛋白含量明显增加(P<0.05).与造模前 1 d比较,造模后 14、28 d D、N、S组 MWT明显降低(P<0.05);与D组比较,造模后28 d S组MWT明显升高,脊髓胶质细胞GLT-1 及GLAST mRNA表达量和蛋白含量明显增加(P<0.05).结论 脊髓电刺激减轻糖尿病大鼠神经痛的机制可能与上调脊髓胶质细胞 GLT-1 及 GLAST基因的表达有关.