Abundant expression and functional participation of TRPV1 at Zusanli acupoint (ST36) in mice: mechanosensitive TRPV1 as an “acupuncture-responding channel”

BMC Complementary and Alternative Medicine

Research Article

Ching-Liang Hsieh¹  Shu-Yih Wu²  Yi-Wen Lin³  Wei-Hsin Chen⁴ 

[1] Acupuncture Research Center, China Medical University, 91 Hsueh-Shih Road, 40402, Taichung, Taiwan;Graduate Institute of Integrated Medicine, College of Chinese Medicine, China Medical University, 91 Hsueh-Shih Road, 40402, Taichung, Taiwan;Department of Chinese Medicine, China Medical University Hospital, 2 Yuh Der Road, 40402, Taichung, Taiwan;Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, 91 Hsueh-Shih Road, 40402, Taichung, Taiwan;Graduate Institute of Acupuncture Science, College of Chinese Medicine, China Medical University, 91 Hsueh-Shih Road, 40402, Taichung, Taiwan;Acupuncture Research Center, China Medical University, 91 Hsueh-Shih Road, 40402, Taichung, Taiwan;Graduate Institute of Biotechnology, College of Agriculture And Natural Resources, National Chung Hsing University, 250 Kuo Kuang Rd, 402, Taichung, Taiwan;

关键词: Acupuncture;    TRPV1;    TRPV4;    ASIC3;    Mechanotransduction;    Calcium wave propagation;   

DOI  :  10.1186/1472-6882-14-96

 received in 2013-07-10, accepted in 2014-02-13,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundAcupuncture is a therapy that involves applying mechanical stimulation to acupoints using needles. Although acupuncture is believed to trigger neural regulation by opioids or adenosine, still little is known about how physical stimulation is turned into neurological signaling. The transient receptor potential vanilloid receptors 1 and 4 (TRPV1 and TRPV4) and the acid-sensing ion channel 3 (ASIC3) are regarded as mechanosensitive channels. This study aimed to clarify their role at the Zusanli acupoint (ST36) and propose possible sensing pathways linking channel activation to neurological signaling.MethodsFirst, tissues from different anatomical layers of ST36 and the sham point were sampled, and channel expressions between the two points were compared using western blotting. Second, immunofluorescence was performed at ST36 to reveal distribution pattern of the channels. Third, agonist of the channels were injected into ST36 and tested in a mouse inflammatory pain model to seek if agonist injection could replicate acupuncture-like analgesic effect. Last, the components of proposed downstream sensing pathway were tested with western blotting to determine if they were expressed in tissues with positive mechanosensitive channel expression.ResultsThe results from western blotting demonstrated an abundance of TRPV1, TRPV4, and ASIC3 in anatomical layers of ST36. Furthermore, immunofluorescence showed these channels were expressed in both neural and non-neural cells at ST36. However, only capsaicin, a TRPV1 agonist, replicated the analgesic effect of acupuncture when injected into ST36. Components of calcium wave propagation (CWP, the proposed downstream sensing pathway) were also expressed in tissues with abundant TRPV1 expression, the muscle and epimysium layers.ConclusionsThe results demonstrated mechanosensitive channel TRPV1 is highly expressed at ST36 and possibly participated in acupuncture related analgesia. Since CWP was reported by other to occur during acupuncture and its components were shown here to express in tissues with positive TRPV1 expression. These findings suggest TRPV1 might act as acupuncture-responding channel by sensing physical stimulation from acupuncture and conducting the signaling via CWP to nerve terminals. This study provided a better understanding between physical stimulation from acupuncture to neurological signaling.

【 授权许可】

Unknown   
© Wu et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited.