Abstract
Objectives: The aim of this study was to examine the release of nitric oxide (NO) and cGMP in response to electroacupuncture (EA) stimulation in the acupuncture point (acupoint), compared to the non-meridian control area. Methods: Thirty samples of dermal microdialysis data were collected from 24 volunteers at pericardium (PC) 4 and control area. EA was applied to PC 3 by using a 5-V pulse with a duration of 1.0 milliseconds at 10 Hz for 15 minutes. Dialysate samples were continuously collected 20 minutes each before, during, and after EA for two hours. Total nitrite and nitrate (NOx−) and cGMP in the dialysate were quantified in a blinded fashion. Results: Dialysate NOx− concentrations were decreased during a 120-minute dialysis in all groups, but reduced NOx− levels were attenuated predominantly in PC 4 acupoint at 20–40 minutes after EA PC 3. cGMP concentrations were significantly enhanced in acupoint PC 4 by EA PC 3, but not in the non-meridian area. Conclusion: We suggest that the attenuation of NOx− reduction during dialysis reflects an increase in NO release induced by EA stimulation in acupoint and that cGMP mediates the signaling functions of NO to improve local microcirculation, which, at least in part, contributes to the effects of acupuncture.