For the purpose of elucidating the role of cholinergic nervous system in the process ofacupuncture anesthesia

the content of acetylcholine(ACh)and the activity of acetylcholinesterase(ACHE)in different regions of brains of rats were estimated without and after electro-acupunctureinduction.The ACh content was estimated with microbioassay method on frog rectus abdominis.TheAChE activity was determined by Hestrin's colorimetric method.The points needled were“Shuigou”(i.e.“Renzhong”)and “Chengjiang”.The frequency of electric stimulation was 60000/min.The results of experiments showed that the ACh content and the AChE activity were significant-ly in (?)sed in the hypothalamus after the beginning of induction for 30 minutes as comparedwith com(?)nimals.Mean contents of ACh in this region of 42 pairs of rats were 0.350±0.077μg/gm for control and 0.738±0.147 μg/gm for needled rats;the difference was statisticallysignificant(P<0.05).Mean activity of AChE in the hypothalamus of 60 pairs of rats were 24.812+0.464 μ moles/100mg tissue/30 min.(at 37℃)for control and 26.321±0.581 μ molesfor needled animals

(0.05>P>0.02).There were no significant changes in thalamus

caudatenuclei and cerebral cortex.The results suggested that ACh in the hypothalamus might play a role in analgesic and regu-latory effects of acupuncture anesthesia.