For the purpose of understanding the relationship between cholinergic neurotransmitter and the mechanism of acupuncture analgesia

the blood cholinesterase(ChE) activities were estimated before and after acupuncture induction in patients operated under acupuncture anaesthesia and in rats. ChE activity was determined by Hestrin's colorimetric method. In patients with thyroidectomy and removal of thyroid cysts

"Hegu" (L.I.4) and "Neiguan" (P.6) were needled

whle in those with subtotal gastrectomy Renzhong (Du 26) and Chengjiang(R. 24) were needled. In rats "Shuigou" (i.e. Renzhoug) and Chengjiang were needled. The frequency of electric stimulation applied in thyroid operations was 3

600/min.

in subtotal gastrectomy and in rats was 60

000/min. ChE activity in the veinous blood of 100 patients undergoing thyroid operations and 32 patients subjected to subtotal gastrectomy under acupuncture anaesthesia indicated no significant change after 20 minutes inducction (P>0.05). There were also no significant differences of blood ChE activity in 24 rats after 30 minutes electro-acupuncture induction in comparison with 24 control animals

and in 20 rats during the rise of pain threshold by acupuncture induction in comparison with 20 control animals. The results seem to suggest that the peripheral cholinergic transmitter may not play an important role in the mechanism of acupuncture analgesia.