远近配穴电针对自体髓核移植大鼠脊髓p38丝裂原活化蛋白激酶及环磷酸腺苷表达的影响

目的:探讨远近配穴针刺对自体髓核移植腰痛大鼠机械缩爪阈和脊髓中p 38丝裂原活化蛋白激酶(p 38 MAPK)及环磷酸腺苷(cAMP)表达的影响,为理解不同针刺处方作用机制提供实验依据。方法:雄性SD大鼠随机分为正常组、模型组、假手术组、全穴组、近穴组和远穴组,每组13只,采用自体髓核移植方法建立腰痛模型。全穴组电针双侧腰5(L 5)"夹脊""大肠俞""委中"和"昆仑",近穴组电针双侧L 5"夹脊"和"大肠俞",远穴组电针双侧"委中"和"昆仑"。电针治疗每天1次,每次20min,连续治疗7d。于术前1d和术后3、5、7d观察大鼠行为学和机械痛阈值;于术后8d,取脊髓L 4-L 6节段,用免疫组织化学法和免疫蛋白印迹法测定p 38 MAPK表达,用酶联免疫吸附法测定cAMP含量。结果:与正常组相比,模型组在术后3d表现出明显痛觉过敏,持续至术后7d;与模型组比较,3个针刺组机械痛阈变化百分率提高(P0.01);全穴组、近穴组痛阈升高趋势优于远穴组(P0.01,P0.05)。与正常组相比,模型组脊髓p38MAPK表达水平显著上升(P0.01);与模型组相比,近穴组、远穴组、全穴组p 38MAPK表达水平显著下降(P0.01,P0.05),以近穴组最为明显,全穴组次之。与正常组相比,模型组脊髓cAMP表达明显升高(P0.01);与模型组相比,近穴组、全穴组cAMP表达下降(P0.01,P0.05)。结论:远部取穴、近部取穴和远近配伍取穴电针均能对内源性髓核刺激导致的腰痛模型大鼠7d内痛阈和脊髓p 38 MAPK、cAMP(除远穴组外)表达产生调节作用,近部取穴和远近配伍取穴调节作用更加明显。

Effect of Electroacupuncture at Distal and Proximal Acupoints on Expression of Spinal p 38 Mitogen-activated Protein Kinase and Cyclic Adenosine 3',5'-monophosphate in Rats with Lumbago

Objective To observe the influence of Electroacupuncture(EA)stimulation of different distal-proximal acupoints combination groups on pain reaction,spinal p 38mitogen-activated protein kinase(p 38MAPK)expression and cyclic adenosine 3',5'-monophosphate(cAMP)content in experimental lumbago rats.Methods Seventy-eight male SD rats were randomized into normal,model,sham operation,EX-B 2-BL 25(proximal acupoints,PA),BL 40-BL 60(distal acupoints,DA)and DA+PA groups.The lumbago model was established by implanting the autologous nucleus pulposus to the site close to the left L 5dorsal root ganglion and the surface of dura mate of spinal cord.EA(2Hz/100 HZ,1-3mA)was applied at bilateral EX-B 2-BL 25 or BL 40-BL 60 or both for 20 minutes,once daily for 7days.The mechanical pain threshold was measured,and the expression of p 38 MAPK in the lumbar spinal cord was detected by immunohistochemistry and Western blot,separately.The content of cAMP in spinal cord(L 4-L 6)was measured by enzyme-linked immunosorbent assay(ELISA).Results After modeling,the mechanical pain threshold percentages were significantly decreased on day 3,5and 7(P<0.01),and after EA stimulation of DA,PA and DA+PA,the decreased pain threshold was significantly increased at the 3time-points(P<0.01),and the effects of both PA and DA+PA were markedly superior to that of DA(P<0.05,P<0.01).Following modeling,lumbar spinal p38 MAPK immunoactivity and protein expression,and cAMP content were obviously up-regulated(P<0.01).Compared with the model group,the levels of p 38 MAPK immunoactivity and protein expression in the 3EA groups and the sham group,and cAMP contents in both PA and DA+PA groups(not in the DA and sham groups)were considerably down-regulated(P<0.01,P<0.05).Conclusion EA stimulation of distal+proximal acupoints and proximal acupoints near the focus can raise pain threshold in lumbago rats,which may be associated with their effects in suppressing lumbago-induced increase of expression of spinal p 38 MAPK protein and cAMP content.The effects of EA of distal+proximal acupoints and proximal acupoints are better than those of EA of simple distal acupoints.