Effect of electro-acupuncture at Foot-Yangming Meridian on somatostatin and expression of somatostatin receptor genes in rabbits with gastric ulcer.

Aim: To discuss the protective effect of electroacupuncture at the Foot-Yangming Meridian on gastric mucosal lesion, somatostatin (SS) and the expression of SS receptor genes (SSR(1)mRNA ) in rabbits with gastric ulcer and to further explore the relative specificity of meridians and viscera at gene expression level.

Methods: Forty rabbits were randomly divided into control group (A), gastric ulcer model group (B), Foot-Yangming Meridian group (C), Foot-Shaoyang Meridian group (D) and Foot-Taiyang Meridian group (E). The gastric ulcer model was prepared by infusing alcohol into stomach. Groups C-E were treated with electro-acupuncture at points along the above meridians using meridian stimulating instruments for 7 d respectively. By the end of treatment, the index of gastric ulcer was determined, the amount of epidermal growth factor(EGF) and somatostatin was measured by radioimmunoassay (RIA). SS-R(1)mRNA expression in gastric mucosa was determined by RT-PCR.

Results: The value of EGF in model group was obviously lower (73.6+/-14.8 vs 91.3+/-14.9 pg/mL, P<0.01) than that in control group. The index of gastric ulcer, content of SS and expression of SSR1mRNA in gastric mucosa were significantly higher than those in control group (24.88+/-6.29 vs 8.50+/-2.98 scores, P<0.01; 2978.6+/-587.6 vs 1852.4+/-361.7 mIU/mL, P<0.01; 2.56+/-0.25 vs 1.04+/-0.36, P<0.01). The value of EGF in Foot-Yangming Meridian group was higher than that in model group (92.2+/-6.7 vs 73.6+/-14.8 pg/mL, P<0.01). The index of gastric ulcer, content of SS and expression of SS-R(1)mRNA in gastric mucosa were significantly lower than those in control group (10.88+/-3.23 vs 24.88+/-6.29 scores, P<0.01; 1800.2+/-488 vs 2978.6+/-587.6 mIU/mL, P<0.01; 1.07+/-0.08 vs 2.56+/-0.25 mIU/mL, P<0.01). Compared to the model group, the content of SS and expression of SSR1mRNA in gastric mucosa in Foot-Shaoyang Meridian group decreased (2441.0+/-488.vs 2978.6+/-587.6 mIU/mL, P<0.05;1.73+/-0.16 vs 2.56+/-0.25 mIU/mL, P<0.01). But the above parameters in Foot-Taiyang Meridian group did not improve and were significantly different from those in Foot-Yangming Meridian group (P<0.05).

Conclusion: Electro-acupuncture at Foot-Yangming Meridian can protect gastric mucosa against injury. The mechanism may be related to the regulation of brain-gut peptides and the expression of SSR(1)mRNA.