不同电针强度对佐剂性关节炎大鼠镇痛效果的影响

【目的】探讨电针强度对电针镇痛效果的影响。【方法】复制大鼠佐剂性关节炎模型,随机分成强电针组、中电针组和对照组,强电针组、中电针组分别以相同电针波型、频率和不同电针强度(前者5.5 mA,后者3.5 mA)刺激“昆仑”和“阳陵泉”穴,对照组只用同样方法固定而不针刺,比较电针前后3组大鼠痛阈的变化。【结果】电针治疗后,中强度电针组和高强度电针组的患侧痛阈均比对照组高(均P<0.01),而中强度电针组的镇痛效果比高强度电针组更优(P<0.05)。两个针刺组的健侧痛阈均有上升(与对照组比均P<0.05),但针刺组间比较未见显著性差异(P>0.05)。【结论】对于急性关节炎疼痛,在相同波型和频率的情况下,中强度电针的镇痛效果优于高强度电针,提示这种镇痛效果可能与中枢的参与有关。

Analgesic Action Produced by Electroacupuncture of Different Intensity in Adjuvant Arthritis Rats

Objective] To observe analgesic action produced by electvoacupuncture (EA) of different intensity in adjuvant arthritis (AA) rats. Methods] AA rat models were induced and the rats were randomized into 3 groups: group A, group B and group C. Group A and group B were treated with EA on points of Kunlun (BL60) and Yangtingquan (GB34) at the same wave type and wave frequency but at different electric current (3.5mA and 5.5mA respectively). Group C was performed with mimic EA. Pain threshold (PT) in the three groups before and after EA was observed. Results] After EA, PT of the affected limb in group A and group B was increased (P<0.01 as compared to group C) and the analgesic action in group A was superior to that in group B (P<0.05). PT of healthy limb in group A and group B was also increased (P<0.05 as compared to group C) while the difference between the two groups was insignificant (P>0.05). Conclusion] Analgesic action of EA at the same wave type and wave frequency while at different electric current is different: analgesic action at middle-intensity current is superior to that at large-intensity current; its possible mechanism is related to the participation of central nervous system.