• The Korean Journal of Pain
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• 제13권2호
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• pp.137-142
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• 2000

Background: Systemic or intrathecal administration of gabapentin has been shown to reverse various pain states. However, until now, the effect of intracerebroventricular (ICV) gabapentin to noxious stimuli has not been reported. The authors' aim of this study was to determine the effect of ICV gabapentin on the inflammatory nociceptive model, formalin test, in rats. Methods: ICV catheters were implanted under halothane anesthesia. For the nociceptive test, $50{\mu}l$ of 5% formalin was subcutaneously injected into the hindpaw. The effect of ICV gabapentin, administered 10 min before formalin injection, were examined on flinching, mean arterial pressure and heart rate evoked by a injection of formalin. Results: Injection of formalin into the paw resulted in a biphasic flinching and cardiovascular response. ICV gabapentin produced a dose-dependent suppression of the flinching and mean arterial pressure response during phase 1. In contrast, in phase 2, ICV gabapentin did not attenuate the pain behavior. ICV gabapentin did not affect on the baseline mean arterial pressure and heart rate. Conclusions: ICV gbapentin was effective for the acute noxious stimulus but it had no effect on the facilitated states induced by tissue injury.

• Journal of Acupuncture Research
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• 제23권6호
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• pp.199-205
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• 2006

Objectives : The present study was conducted to evaluate the analgesic effects of automatically controlled heating acupuncture(ACHA) using 2 different pain models(acute pain and neuropathic pain) and 2 different stimulation conditions (heating $41.5^{\cdot}C$ and heating $44.5^{\cdot}C$) in Sprague-Dawley rats. Methods : Tail flick latency(TFL) to a noxious radiant heat stimulus in lightly anesthetized rats was measured before and after ACHA stimulation for 5-min at the Zusanli(ST36) acupoint. For the neuropathic surgery, the right superior caudal trunk was resected at the level between S1 and S2 spinal nerves innervating the tail. Two weeks after the nerve injury, ACHA stimulation($41.5^{\cdot}C$ or $44.5^{\cdot}C$) was delivered to Zusanli(ST36) for 5 min. The behavioral signs of warm allodynia were evaluated by the tail immersion test (i.e. immersing the tail in warm $water(40^{\cdot}C)$ and measuring the latency to an abrupt tail movement) before and after the ACHA stimulation. Results : In the TFL test, ACHA stimulations under both the conditions above produced more potent analgesic effects than plain acupuncture(PA, acupuncture needle insertion only) and control(no treatment). In the tail immersion test, ACHA stimulations under all of the conditions had markedly relieved the warm allodynia signs. Conclusion : Automatically controlled heating acupul1cture produced analgesic effecs in acute and neuropathic pains.