Effects of different-intensity laser acupuncture at two adjacent same-meridian acupoints on nitric oxide and soluble guanylate cyclase releases in human

Objectives: The aim of this study was to detect the influences of LA at nonacupoint and two adjacent acupoints of pericardium meridian on the releases of NO and sGC in 20 healthy subjects. Methods: Different intensities (12, 24, 48 mW) of infrared laser were used for irradiating Jianshi (PC5), Ximen (PC4) acupoints and nonacupoint for 20, 40 minutes, respectively. Semi-circular tubes were taped to the skin surface and filled with NO-scavenging compound for 20 minutes to capture NO and sGC, which were measured using spectrophotometry in a blinded fashion. Results: As the increase in the intensity of LA stimulation, the levels of NO releases over acupoints all were significantly increased, NO releases in nonacupoints following the same treatment only changed slightly, sGC amounts were observably enhanced over acupoints, but did not any change in nonacupoint area. Different intensities of LA treatments can sensitively affect the NO and sGC releases over acupoints. This indicated that LA-induced releases of the NO and sGC were specific to acupoints. Conclusions: This is the first evidence reporting that LA induced significant elevations of NO-sGC releases over acupoints, and the enhanced signal molecules contribute to local circulation, which improves the beneficial effects of the therapy.