福尔马林致痛提高大鼠中枢μ阿片受体密度及电针的加强作用

INCREASE OF μ OPIOID RECEPTOR DENSITY IN RAT CENTRAL NERVOUS SYSTEM FOLLOWING FORMALIN NOCICEPTION AND ITS ENHANCEMENT BY ELECTROACUPUNCTURE

用放射自显影方法观察到；（１）大鼠脚掌注射福尔马林后，某些与镇痛有关的脑区如尾核头部、伏隔核、杏仁核、中央灰质、脚间核、中缝大核、脊髓背角等结构中μ阿片受体密度明显增加（Ｐ＜０．０５，Ｐ＜０．０１）；（２）给予电针抑制痛反应的大鼠，在其大部分上述结构及扣带回、隔区、视前内侧区、内膝体、上丘、中缝背核及中央上核受体密度明显增加；与福尔马林注射组相比，脚间核、中央灰质尾端腹外侧区、腰膨大背角的受体密度进一步增加。从而在受体水平支持伤害性刺激可以激活体内内阿片肽能活动，而电针可以加强这一活动的设想。

Using receptor autoradiography it was found: (1)After formalin injection in the rat hind paw, the mu opioid receptor density was significantly increased in cerium central areas related to antinociception, i. e., the caudate nucleus, nucleus accumbens,amygdaloid nucleus, periaqueductal gray, interpeduncular nucleus, nucleus raphe maguns and spinal dorsal horn. (2)In addition to most of above mentioned central areas,in rat whose noxious responses were inhibited by electroacupuncture, there was a significant increase of receptor density in the cingulate cortex, septal area, preoptic area, superior central nucleus, superior colliculus and medial geniculate body. In comparison with the ratS with formalin injection alone, the receptor density in the interpeduncular nucleus, the ventrolateral part of the caudal periaqueductul gray and spinal dorsal horn of the lumbar enlargement was further increased in the rats showing electroacupuncture analgesia. The above results provide further evidence supporting the postulation that noxious stimulation is capable of activating endogenous opioid peptidergic system which is further enhanced by electroacupuncture.