Increasing Efficiency of Repetitive Electroacupuncture on Purine- and Acid-Induced Pain During a Three-Week Treatment Schedule

Abstract

Acupuncture (AP) is an important constituent of the therapeutic repertoire of traditional Chinese medicine and has been widely used to alleviate chronic painful conditions all over the world. We studied in rats the efficiency of electroacupuncture (EAP) applied to the Zusanli acupoint (ST36) as an analgesic treatment over a 3-week period of time on purine (α,β-methylene ATP, dibenzoyl-ATP)- and acid (pH 6.0 medium)-induced pain in the rat paw. The two ATP derivatives stimulated P2X3 and P2X7 receptors, respectively, while the slightly acidic medium stimulated the “acid-sensitive ion channel 3” (ASIC3). It was found that the P2X7 receptor and ASIC-mediated pain was counteracted by EAP with greater efficiency at the end than at the beginning of the treatment schedule, while the P2X3 receptor–mediated pain was not. Our findings have important clinical and theoretical consequences, among others, because they are difficult to reconcile with the assumption that AP is primarily due to the release of peripheral and central opioid peptides causing the well-known tolerance to their effects. In consequence, AP is a convenient therapeutic instrument to treat subacute and chronic pain.

Purinergic ATP triggers moxibustion-induced local anti-nociceptive effect on inflammatory pain model

“…In this study, we firstly found that moxibustion at ST36 is also a painkiller in animal inflammatory pain model. In view of purinergic signalling has close relationship with various pain and the growing evidence for purinergic signalling, especially adenosine, could trigger analgesic effect induced by needle acupuncture [14][15][16][17][18][19][20][21][22], we wondered if purinergic signalling participates in moxibustion-induced analgesia. Here, we found that moxibustion could trigger high level of Fig.…”

“…In this study, we firstly found that moxibustion at ST36 is also a painkiller in animal inflammatory pain model. In view of purinergic signalling has close relationship with various pain and the growing evidence for purinergic signalling, especially adenosine, could trigger analgesic effect induced by needle acupuncture [ 14 – 22 ], we wondered if purinergic signalling participates in moxibustion-induced analgesia. Here, we found that moxibustion could trigger high level of extracellular ATP release at ST36, and the time course of ATP release in ST36 acupoint was consistent with moxibustion-induced analgesia effect, which indicated that purinergic ATP might have played a notable role in moxibustion-induced local anti-nociceptive effect.…”

“…In this study, ST36 acupoint (also named Zusanli), located on the posterior lateral side of the knee joint, about 5 mm below the fibula head) was applied to reveal the analgesic effect of moxibustion on chronic pain in that it was proved that acupuncture (needle stimulation) or moxibustion at ST36 generated anti-nociceptive effect in rodent models of chronic pain [ 14 , 20 , 22 , 26 , 27 , 31 ]. Based on the clinical practice of moxibustion to the pain management [ 32 ], we set up 30-min treatment duration to the right ST36 with a lighted moxa stick (diameter 4 mm, length 120 mm, made specially for experiment animals by Nanyang Hanyi moxa LLC, Henan, China) (Fig.…”

“…and to address the potential mechanism of acupuncture-induced analgesia [9][10][11][12][13]. In previous studies, apart from adenosine (ADO) and A1 receptor that were identified to mediate local anti-nociceptive effect of acupuncture [14,15], purinergic receptors A2a, P2X3, P2X4, and P2X7 have also been applied to punch the truth of acupuncture analgesia [16][17][18][19][20][21][22]. Moxibustion is one of important members in traditional Chinese medicine (TCM) therapies, which is recognized to share equal values with acupuncture in treating diseases in the traditional medical system of China [11].…”