家兔黑质内注射海人酸对电针镇痛和吗啡镇痛的影响

<正> 中脑黑质致密部是多巴胺神经元中(Do-paminergic Neuron)比较集中的部位由此发出黑质纹体束主要通往同侧尾核、壳核和中央杏仁核。近年来有报道提示黑质纹体多巴胺系统可能有对抗电针镇痛和吗啡镇痛的作用。本文将海人酸(Kainic Acid KA)直接注入家兔黑质,观察黑质神经元被损毁后,对电针镇痛和吗啡镇痛的影响,并用连续切片、染色和荧光组织化学的方法,观察了神经元被损毁的情况。方法实验对象造体重为2～3公斤的家兔39只,雌雄未限。电针取穴为一侧相当“足三

INFLUENCES OF INTRANIGRAL INJECTION OF KAINIC ACID ON ELECTROACUPUNCTURE ANALGESIA AND MORPHINE ANALGESIA IN THE RABBITS

The effect of the substantia nigra (SN) injection of the neurotoxic agent, kainic acid (KA) 2μg/μl on electroacupuncture analgesia and morp- hine analgesia were studied in rabbits. The pain threshold was determined by the latency of withdrawal of head when the radiant heat was applied on the nose tip of rabbits. The point of electroacupuncture analgesia was "Zusanli" The dosage of morphine was 3mg/kg sc. The serial section of all experimental rabbit's brain was made. The KA destruction was observed with fluorescence histochemistry and toluidine blue stain. The results suggest that KA destruction of the DA ergic neurons in the pars compacta of SN enhanced the analgesic effects of electroacupuncture or morphine. Furthermore, the DA ergic neurons of SN might play an inhibitory effect on the analgesic effects of acupuncture or morphine. There is no correlation between acupuncture analgesia and morphine analgesia was found before intranigral injection of KA. But a positive correlation was shown between both analgesic methods after intranigral injection of KA. At 8-10 days time after KA injection, the cell bodies of DA ergic neurons disappeared and accmpanied by glial hyperplasia in the pars compacta of SN.