It has been demonstrated that the following three neuronal systems playan important role in different kinds of analgesia

i. e.

β-endorphinergic(B-END) system in hypothalamic arcuate nucleus (ARC)

serotonergic (5-HT)system in dorsal raphe nucleus (DR) and noradrenergic(NE) system in locuseoeruleus (LC). Morphological studies have revealed that there are reciprocalnervous innervations among these three nuclei. In the last decade

the role and theinterrelationship of ARC

DR and LC in acupuncture analgesia (AA) (Acu-points: "Renzhong" and "Chenjiang" or "Zusanli" and "Sanyinjiao") werestudied on rats in our laboratory

mainly with behavioral pain test andelectrophysiological technique combined with neurochemieal

fluorescent histo-chemical

immunocytochemieal and neurophrmaeological methods.