RESUMO
Objective To investigate the effect of electroacupuncture at points Xiaohai and Xiajuxu on the expressions of tumour necrosis factor-α (TNF-α) and choline acetyltransferase (ChAT) in serum and nicotinic acetylcholine receptorα 7 (α 7 nAchR) in duodenal tissues in a rat model of duodenal ulcer (DU) and preliminarily explore the relative specificity of He-Sea point in “treating visceral diseases with He-Sea point”.Methods Forty healthy SD rats were randomized into blank (A), model (B), Xiaohai (C) and Xiajuxu (D) groups, 10 rats each. A rat model of DU was made by subcutaneous injection of 10% cysteamine hydrochloride at the right buttock. After successful model making, group C was given electroacupuncture at point Xiaohai and group D, at point Xiajuxu. Duodenal tissue ulcer was macroscopically observed and scored in every group of rats. Rat serum expression of TNF-α was determined by double antibody sandwich enzyme-linked immunosorbent assay (ELISA); rat serum expression of ChAT, by ultraviolet spectrophotometry & colorimetry; rat duodenal expression ofα7 nAchR, by Western blot.Results After model making, the duodenal ulcer score was significantly higher in groups B, C and D than in group A (allP0.05) and was significantly higher in group D than in group B (P<0.01) or C (P<0.05).α7 nAchR expression was significantly higher in groups C and D than in group B (bothP<0.01). There was a positive correlation between ChAT andα7 nAchR expressions in every group (r=0.444,P=0.007).Conclusions Electroacupuncture at both points Xiaohai and Xiajuxu can reduce the duodenal ulcer score and serum TNF-α expression and increase serum ChAT and duodenalα7 nAchR expressions in DU rats. The results show that the therapeutic effect of electroacupuncture on duodenal ulcer may be produced by regulating TNF-α. Its mechanism may be activating cholinergic anti-inflammatory pathway to produce an anti-inflammatory effect. The effect being better in group D than in group C suggests that Xiajuxu has the relative specificity.