Metabolism modulation in rat tissues in response to point specificity of electroacupuncture

Zusanli (ST36) and Neiguan (PC6) are acupoints along two meridians. To demonstrate point specificity, we investigated the effects of ST36 and PC6 in electroacupuncture (EA)-treated rats. The rats were subjected to sham acupuncture at ST36 without electric stimulation, EA at ST36, or EA at PC6. Heart and stomach tissues were collected for metabolite profiling. Each type of stimulation resulted in a different metabolite composition in the rat heart and stomach tissues. In the heart tissues, EA at ST36 affected a wider range of metabolite pathways than did EA at PC6, whereas similar numbers of metabolites in the stomach tissues were affected by EA at ST36 and PC6. The pathways affected by EA at ST36 differed from those affected by EA at PC6, and a group of common metabolites were reversely regulated by these two acupoints. This study demonstrated point specificity effectively modulated metabolism in rat heart and stomach tissues. The results indicate that heart stimulation may be connected to the stomach through the pericardium meridian (as described in traditional Chinese medicine), explaining why acupuncture applied to the stomach meridian can be an alternative treatment for gastric and heart diseases.