• Journal of Acupuncture Research
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• v.21 no.6
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• pp.51-62
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• 2004

Objective: To investigate the analgesic effect and its serotonergic mechanism, especially related with 5-HTI and 5-HT2 receptor, of electroacupuncture(EA) in the rat model of collagen-induced arthritis(CIA). Methods : Immunization of male Sprague-Dawley rats with bovine type II (C II) collagen emulsified in Freund's incomplete adjuvant, followed by a booster injection 14 days later, leads to development of arthritis in more than 70% of rats by 21 days postinjection. After three weeks of first immunization, EA stimulation(2 Hz, 0.07 mA, 0.3 ms) was delivered into Jogsamni($ST_{36}$) for 30 minutes. Analgesic effect was evaluated by tail flick latency(TFL). We compared the analgesic effect of EA with TFLs between pretreatment of normal saline and pretreatment of spiroxatrine (5-HT1 receptor antagonist, 1mg/kg, intraperitoneal) and spiperone (5-HT2 receptor antagonist, 1 mg/kg, intraperitoneal) in CIA. Results : 1. TFLs were gradually decreased in CIA as increasing severity of arthritis. 2. Jogsamni($ST_{36}$) EA stimulation in CIA increased TFLs and the effect lasted for 60 minutes. 3. Increased TFLs with Jogsamni($ST_{36}$) EA stimulation were inhibited by pretreatment of spiroxatrine and spiperone in CIA. Conclusions : Jogsamni($ST_{36}$) EA showed analgesic effects in CIA The analgesic effects of Jogsamni($ST_{36}$) EA were inhibited by spiroxatrine and spiperone pretreatment. These observations suggest that 5-HT1 and 5-HT2 serotonergic receptor, which involve the release of serotonin neurotransmitter, play an important roles in analgesic mechanism of EA stimulation.

• Journal of Acupuncture Research
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• v.22 no.2
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• pp.19-32
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• 2005

Objectives : to evaluate the analgesic effect of bee venom acupuncture on Choksamni (ST36) in the collagen-induced arthritis rats and investigate the role played by serotonergic receptor subtypes (5-HT1a, 5-HT2a) in the antinociceptive effect of bee venom acupuncture in a thermal hyperalgesia test Methods : Experiments were performed on 5 week-aged 60 male Sprague-Dawley rats according to National Institute of Health guidelines and the ethical guidelines of the International Association for the Study of Pain (IASP). Arthritis was induced with arthrogenic collagen emulsion (Bovine type II collagen ${\mu}g$ with incomplete Freund's adjuvant $100\;{\mu}g$). The onset of arthritis was considered to be present when erythema and swelling were detected in at least one joint. The thermal hyperalgesia was evaluated weekly with tail flick test in the rats of severity grade 3 without any injury at tail and foot (including inflammation, ulceration, snap). In the fourth week after first immunization, the analgesic effect of bee venom acupuncture (Choksamni, ST36) was measured with consecutive tail flick latency after intraperitoneal injection of spiroxatrine (1mg/kg) and spiperone (1mg/kg). Results : Chronic inflammatory pain was induced as time elapsed after the immunization of arthrogenic collagen and the maximum value was reached from third to fifth week. Chronic inflammatory pain induced by CIA was inhibited by bee venom acupuncture on the left ST36. The analgesic effect of bee venom acupuncture was inhibited by intraperitoneal injection of 5-HT1a antagonist spiroxatrine and 5-HT2a antagonist spiperone. Conclusions : Therefore, a conclusion. that the analgesic effect of bee venom acupuncture in the chronic inflammatory pain is partially mediated by 5-HT1a and 5-HT2a receptors can be made.