Yun Kyu Lee

Acupuncture suppresses reinstatement of morphine-seeking behavior induced by a complex cue in rats.

Morphine causes physical and psychological dependence for individuals after repeated-use. Above all, our previous study showed that acupuncture attenuated reinstatement of morphine-seeking behavior induced by pharmacological cue. In this study, we investigated whether acupuncture could suppress the reinstatement of morphine-seeking behavior induced by the combination of environmental and pharmacological cues and the possible neuronal involvement. Male Sprague-Dawley rats were trained to self-administer morphine (1.0 mg/kg) for 3 weeks. Following the withdrawal phase (7 days), the effects of acupuncture on reinstatement of morphine-seeking behavior were investigated. For the investigation of neuronal involvement, the GABAA receptor antagonist bicuculline and the GABAB receptor antagonist SCH 50911 were pre-treated. Morphine-seeking behavior induced by combination of re-exposure to the operant chamber and morphine injection was suppressed perfectly by acupuncture at SI5, but not at the control acupoint LI5 and this effect was blocked by pre-treatment with the GABA receptor antagonists. This study suggests that acupuncture at SI5 can be considered as a predominant therapy for the reinstatement of morphine-seeking behavior in humans.

Acupuncture at HT7 suppresses morphine self-administration at high dose through GABA system

In the previous study, acupuncture at HT7 has shown to attenuate the self-administration of morphine at a low dose (0.1mg/kg). In this study, it was further investigated whether acupuncture at HT7 could attenuate the morphine self-administration at a high dose (0.5mg/kg). Male Sprague-Dawley rats weighing 270-300g were used. After surgery of catheterization, animals were trained to self-administer morphine solution (0.5mg/kg) using daily 1h session under fixed ratio 1 schedule for 3 weeks. Animals that had shown stable morphine-taking (establish baseline: variation less than 20% of the mean of three consecutive days) were subjected to the acupuncture treatment. Bicuculline and SCH 50911 were used to investigate the possible relation between the effect of acupuncture and the GABA receptor system. Acupuncture at HT7, but not at control acupoint, LI5, suppressed spontaneous morphine-taking behavior significantly. In addition, the effect of acupuncture was blocked by both GABA receptor antagonists. The results of this study suggest that acupuncture at HT7 suppresses morphine-taking behavior through the mediation of GABA receptor system.

Effects of acupuncture on the anxiety-like behavior induced by withdrawal from chronic morphine use

OBJECTIVES In the previous studies, it has been demonstrated that acupuncture treatment was effective on the suppression of withdrawal signs as well as self-administration behavior induced by morphine. Based on, the present study has investigated whether acupuncture could attenuate the anxiety-like behavior induced by withdrawal from chronic morphine treatment. MATERIALS & METHODS Male Sprague-Dawley rats weighing 270-300g were treated saline or morphine hydrochloride (10mg/kg, s.c.) for 2 weeks. Following abstinence of 5days in home cage, rats were subjected to the measurement of anxiety-like behavior in the elevated plus maze. Bicuculline (1mg/kg, i.p.) and SCH 50911 (2mg/kg, i.p.) were used to investigate the possible mechanism of acupuncture effects focusing on the GABA receptors system. RESULTS Acupuncture at HT7 increased the time spent in open arms significantly. Also, these effects of acupuncture at HT7 were blocked by GABAA receptor antagonist. CONCLUSION Results of the present study suggest that acupuncture at HT7 can attenuate anxiety-like behavior induced by withdrawal from chronic morphine treatment through the mediation of GABAA receptor system.

Acupuncture suppresses intravenous methamphetamine self-administration through GABA receptor’s mediation

OBJECTIVES Methamphetamine is one of the widely abused drugs. In spite of a number of studies, there is still little successful therapy to suppress the methamphetamine abuse. Acupuncture has shown to attenuate the reinforcing effects of psychostimulant. Based on, the present study investigated if acupuncture could suppress intravenous methamphetamine self-administration behavior. In addition, a possible neuronal mechanism was investigated. MATERIALS & METHODS Male Sprague-Dawley rats weighing 270-300g were trained to intake food pellet. After catheter implantation, animal was trained to self-administer methamphetamine (0.05mg/kg) intravenously using fixed ratio 1 schedule in daily 2h session during 3 weeks. After training, rats who established baseline (infusion variation less than 20% of the mean for 3 consecutive days) received acupuncture treatment on the next day. Acupuncture was performed at each acupoint manually. In the second experiment, the selective antagonists of GABAA or GABAB receptor were given before acupuncture to investigate the possible neuronal involvement of GABA receptor pathway in the acupuncture effects. C-Fos expression was examined in the nucleus accumbens to support behavioral data. RESULTS Acupuncture at HT7, but not at control acupoint LI5, reduced the self-administration behavior significantly. Also, the effects of acupuncture were blocked by the GABA receptor antagonists. C-Fos expression was shown to be parallel with the behavioral data. CONCLUSIONS Results of this study have shown that acupuncture at HT7 suppressed methamphetamine self-administration through GABA receptor system, suggesting that acupuncture at HT7 can be a useful therapy for the treatment of methamphetamine abuse.