紫杉醇致神经病理性疼痛大鼠脊髓背角 GLT-1的表达变化

摘要

Objective To investigate the changes of glutamate transporter-1(GLT-1)expression in spi-nal cord dorsal horns of paclitaxel (Taxol)induced neuropathic pain rats. Methods All the 45 male SD rats in this study were divided into 3 groups randomly:control group (Group A),Taxol group (Group B)and vehi-cle group (Group C).No administration was given to animals in group A.Animals in group B were injected in-traperitoneally with Taxol 2 mg/1000g body weight every other day.Animals in group C were injected intrap-eritoneally with Taxol solvent DMSO with the same volume as group B at the same time.Mechanical with-drawal thresholds (MWT)of the rats were measured every day.The spinal cord dorsal horn tissues were taken from 5 rats in each group on day 5,day 7 and day 9 after injection respectively.Western bolting was employed to detect the expressions of GLT-1. Results MWTs declined(P <0.05),and compared with group A and group C ,MWTs in group B decreased(P <0.05)since day 6 after injection,while MWTs showed no signifi-cant change in group A or group C.Compared with groups A and C,expression of GLT- 1 in group B de-creased since day 5 after injection (P <0.05).The ratio of GLT-1/β-actin showed positive significant corre-lation with MWT (r =0.820,P <0.05). Conclusion Mechanical hyperalgesia and downregulation of GLT-1 expressions were found in paclitaxel induced neuropathic pain rats,which implied that GLT-1 may play a role in the pathogenesis of neuropathic pain induced by paclitaxel.%目的：观察紫杉醇诱导的神经病理性大鼠脊髓背角谷氨酸转运体-1(GLT-1)的含量变化。方法雄性 SD大鼠45只,随机分成正常对照组(A 组),紫杉醇处理组(B 组)和紫杉醇溶剂组(C 组),A 组不作任何处理,B 组隔天注射2 mg/1000 g 体重的紫杉醇,C 组隔天注射与 B 组容积相等的紫杉醇溶剂二甲基亚砜。每天检测大鼠的机械缩足阈值(MWT)。注射的第5 d、7 d、9 d 各组均处死5只大鼠,取脊髓背角组织,采用蛋白印迹方法检测各组大鼠 GLT-1的表达。结果 B 组大鼠的机械缩足阈值在注射第6 d 时显著降低(P <0.05),并且明显低于 A、C 组(P <0.05)。A、C 两组的 MWT 值无变化。B 组大鼠 GLT-1的表达在注射第5 d 起明显低于 A、C 两组(P <0.05)。B 组大鼠的 GLT-1/β-actin 的比值与机械缩足阈值呈显著性正相关(r =0.820,P <0.05)。结论紫杉醇诱导的神经病理性疼痛大鼠机械痛敏明显增加,脊髓背角 GLT-1表达下调,GLT-1可能参与了紫杉醇致神经病理性疼痛的发生。