The spinal ganglion a cell body storage of somatic primary-sensory neurons

is considered as an important region for neurochemical research of primary afferent nerves. The present experiment aims at the observation on the Ach content andits changes in the ganglia of 128 rats by means of biochemical methods under theeffect of administration of Neostigmini and application of electroacupunctnrd. Itis found that there are evidence of existance of Ach in the ganglia and whan theAchE activity in the periphery nerve system is inhibited

the Ach content of gangliabecome rised. In addition

during acupuncture (applied at acupoint "Huantiao")analgesia

no apparent changes of Ach content can be visualized in spinal ganglia

however

the level of AchE activity goes up evidently. The foregoing resultsindicate that in the somatic primary-sensory neuron Ach is one of important neu-rotransmitters which may influence and take part in the transmission of sensoryinformation through primary afferent nerves.