背根神经节TrkA、P75NTR受体在大鼠骨癌痛发展过程中的表达变化

摘要

目的 探讨骨癌痛大鼠不同发展阶段神经生长因子受体TrkA、P75NTR在背根神经节的表达变化.方法 建立大鼠骨癌痛模型,随机分为假手术组(S组)和骨癌痛组(C组).瘤细胞植入前及植入后7d、13d和19d分别测定疼痛行为学变化,并检测背根神经节TrkA、P75NTR表达变化.结果 C组大鼠在接种瘤细胞7d后出现骨癌痛,13d、19d疼痛持续发展,与S组比较差异有统计学意义(P＜0.05)；TrkA、P75NTR受体表达在接种后7d开始增加,与S组比较差异有统计学意义(P＜0.05)；C组接种后13d、19 d TrkA、P75受体表达水平高于接种后7 d(P＜ 0.05),接种后19 d受体表达水平与接种后13d比较差异无统计学意义(P＞0.05).结论 骨癌痛大鼠TrkA、P75NTR受体出现异常表达并加剧骨癌痛的发展进程.%Objective To explore the expression of TrkA and P75NTR receptor of nerve growth factor in the dorsal root ganglion (DRG)in the different stages of bone cancer pain development in rats.Methods Rats were divided into sham (S) and bone cancer pain (C)groups,bone cancer pain model were made by inoculation of walker 256 mammary cancer cells in left tibia.Mechanical and thermal hyperalgesia were assessed in the different stages of bone cancer pain development including basehne,day 7,day 13 and day 19 after cancer cells inoculation.Westem blot was used to determine TrkA and P75NTR receptor expression in L4/L5 DRG in cancer and sham rats.Results A reduced tendency in paw withdrawal latency (PWL) and a decreased paw withdrawal threshold (PWT) were observed in C group rats in days 7 after cancer cells inoculation walker,and pain sustainable development in days 13 and 19 as compared to the sham rats.Western blot showed that the total expression of TrkA and P75NTR protein increased in L4-L5 DRG of cancer rats in days 7,and significantly enhanced in days 13 to 19.There was no significant difference of the receptor expression between days 13 and 19.Conclusion The abnormal expression of TrkA and P75NTR receptor exacerbate the process of the bone cancer pain development.