About this Journal Submit a Manuscript Table of Contents
Evidence-Based Complementary and Alternative Medicine
Volume 2012 (2012), Article ID 857123, 8 pages
http://dx.doi.org/10.1155/2012/857123
Research Article

Stimulation of TRPV1 by Green Laser Light

1Shanghai Research Center for Acupuncture and Meridians, 199 Guoshoujing Road, Shanghai 201203, China
2Acupuncture and Moxibution College, Shanghai University of Traditional Chinese Medicine, 1200 Cailun Road, Shanghai 201203, China
3State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, Shanghai 200031, China
4Institute for Biophysics, J. W. Goethe University, Max-von-Laue Straβe 1, 60438 Frankfurt am Main, Germany

Received 20 September 2012; Revised 6 November 2012; Accepted 14 November 2012

Academic Editor: Di Zhang

Copyright © 2012 Quanbao Gu et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Low-level laser irradiation of visible light had been introduced as a medical treatment already more than 40 years ago, but its medical application still remains controversial. Laser stimulation of acupuncture points has also been introduced, and mast-cells degranulation has been suggested. Activation of TRPV ion channels may be involved in the degranulation. Here, we investigated whether TRPV1 could serve as candidate for laser-induced mast cell activation. Activation of TRPV1 by capsaicin resulted in degranulation. To investigate the effect of laser irradiation on TRPV1, we used the Xenopus oocyte as expression and model system. We show that TRPV1 can functionally be expressed in the oocyte by (a) activation by capsaicin ( = 1.1 μM), (b) activation by temperatures exceeding 42°C, (c) activation by reduced pH (from 7.4 to 6.2), and (d) inhibition by ruthenium red. Red (637 nm) as well as blue (406 nm) light neither affected membrane currents in oocytes nor did it modulate capsaicin-induced current. In contrast, green laser light (532 nm) produced power-dependent activation of TRPV1. In conclusion, we could show that green light is effective at the cellular level to activate TRPV1. To which extend green light is of medical relevance needs further investigation.