一般认为针刺镇痛效应存在着穴位相对特异性

如“腰背委中求……”即是对此的描述

而且认为这种特异性和神经系统有关。丘脑腹侧基底核(VB)是躯体感觉特异传导系统第三级神经元所在地

近年来不少资料提示VB和伤害性信息传递有关。与The purpose of the present study was to compare the effects of electroacupuncture at different points on nociceptive responses of VB neurons. The experiments were carried out on rats (280—320g) anaesthetized with urethane (19/kg

i.p.). Single unit activities of VB neurons were extracellularly recorded by means of glass microelectrodes. Noxious stimulation was subcutaneously applied at the left ankle joint by inserting two stainlessneedles. The experiments were divided into three groups. EA. Ⅰ

EA

Ⅱ and EA. Ⅲ. The corresponding points being selected for electroacupuncture in the above three groups were the left "Huantiao" (G30) point

the right "Huantiao" point and the left "Jianlian" (T14) point. The results showed that electroacupuncture at the points in the three groups all could inhibit the nociceptive responses of VB neurons

but electroacupuncture an the left "Huantiao" point (n=11) was more effective than either at the right "Huantian" point (n=9) or at the left "Jianliao" point (n=10). There was a significant difference among the three groups. However

there was no significant difference between EA. Ⅱ and EA. Ⅲ. Thus

the results indicate that there is a relative specificity of points in acupuncture analgesia.