The effect of different frequency electrical acu-stimulation on gastric myoelectrical activity in healthy subjects.

BACKGROUND/AIMS: Acupuncture has been used to treat gastrointestinal symptoms in oriental countries for many years. The underlying mechanism is still not fully understood. METHODOLOGY: Fifteen healthy male volunteers were enrolled into this study. A cutaneous electrogastrography recording was obtained. Two frequencies (2 Hz and 100 Hz) of electrical stimulation were applied to Zusnali or Shousanli point in different sessions. Another non-acu-point (2 cm lateral to Zusanli) without electrical stimulation was used for a control study. RESULTS: There was a significant increase in the percentage of normal frequency during 2 Hz of electrical stimulation on Zusnali (baseline vs. acupuncture, 82.49 +/- 12.87% vs. 93.18 +/- 8.40%, p < 0.01). The percentage of normal frequency did not change significantly, during or after acupuncture, with 100 Hz of electrical stimulation on Zusnali, or 2 Hz and 100 Hz of electrical stimulation on Shousanli. In addition, the percentage of tachygastric frequency and power ratio also changed significantly during 2 Hz of electrical stimulation on Zusnali. However, the change in the percentage of bradygastria and dominant frequency was not statistically significant among all five study sessions during each stage. CONCLUSIONS: The results of this study demonstrated that electrical stimulation, with a frequency of 2 Hz, on Zusanli might enhance the regularity of gastric myoelectrical activity. The effect of acupuncture on gastric myoelectrical activity was acu-point-specific, and that effect was observed with 2 Hz but not 100 Hz electrical stimulation.