Zhen Ci Yan Jiu. 1992 ; 17(1): 7-12.

[Electron microscopic observation on the effect of electroacupuncture (EA) on the ultrastructure of nucleus raphe dorsalis (NRD) in rats]

Xue M, Fan T, Li S.

Department of Anatomy, Henan Medical University, Zhengzhou.

Nucleus raphe dorsalis (NRD) plays an important role in acupuncture analgesia. The aim of this investigation is to determine the effects of electroacupuncture (EA) analgesia on the ultrastructure of NRD. 12 Wistar rats (220-250g) were divided into control and experiment groups. Pain threshold was determined by potassium iontophoretic colorimetry. EA was applied at bilateral "Zusanli" points. The effective analgesia animals and control animals were sacrificed and the NRD were taken out for electron microscopic observation. In EA analgesia groups, NRD was observed the number of the clear round vesicle-containing terminals and clear round vesicles with the granular vesicle-containing terminals showed a significant decrease and sometimes vesicles were emptied. The area of presynaptic terminals were expanded. Some synaptic gaps appeared narrow profiles. Part of the mitochondria and endoplasmic reticulum in neuron and neurogliocytes appeared the expanded profiles. These ultrastructural change of the NRD in EA analgesia might indicate the neurons and neurogliocytes were in active functional state.