There is growing public interest in alternative approaches to addiction treatment and scientific interest in elucidating the neurobiological underpinnings of acupuncture. Our previous studies showed that acupuncture at a specific Shenmen (HT7) points reduced dopamine (DA) release in the nucleus accumbens (NAc) induced by drugs of abuse. The present study was carried out to evaluate the effects of HT7 acupuncture on γ-aminobutyric acid (GABA) neuronal activity in the ventral tegmental area (VTA) and the reinstatement of cocaine-seeking behavior. Using microdialysis and in vivo single-unit electrophysiology, we evaluated the effects of HT7 acupuncture on VTA GABA and NAc DA release and VTA GABA neuronal activity in rats. Using a within-session reinstatement paradigm in rats self-administering cocaine, we evaluated the effects of HT7 stimulation on cocaine-primed reinstatement. Acupuncture at HT7 significantly reduced cocaine suppression of GABA release and GABA neuron firing rates in the VTA. HT7 acupuncture attenuated cocaineprimed reinstatement, which was blocked by VTA infusions of the selective GABA B receptor antagonist 2-hydroxysaclofen. HT7 stimulation significantly decreased acute cocaine-induced DA release in the NAc, which was also blocked by 2-hydroxysaclofen. HT7 acupuncture also attenuated cocaine-induced sensitization of extracellular DA levels in the NAc. Moreover, HT7 acupuncture reduced both locomotor activity and neuronal activation in the NAc induced by acute cocaine in a needle-penetration depth-dependent fashion. These results suggest that acupuncture may suppress cocaine-induced DA release in the NAc and cocaine-seeking behavior through activation of VTA GABA neurons. Acupuncture may be an effective therapy to reduce cocaine relapse by enhancing GABAergic inhibition in the VTA.

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Methamphetamine is one of the widely abused drugs. Nevertheless, there is little predominant therapy for the abuse. In the previous study, acupuncture had shown to attenuate methamphetamine self-administration behavior, and based on, the present study investigated whether acupuncture inhibits the reinstatement of methamphetamine self-administration. As well, a possible neuronal mechanism was investigated. Male Sprague–Dawley rats weighing 270–300 g were trained to intravenously self-administer methamphetamine (0.1 mg/kg) for 3 weeks. Following training, rats who administered stable amount of methamphetamine underwent extinction period of 1 week. Thereafter, priming injection was performed to induce reinstatement, and acupuncture was given immediately before priming. In the second experiment, the selective antagonists of GABAA and GABAB receptors were treated prior to acupuncture to investigate a neuronal mechanism of GABAergic pathway. Acupuncture treatment at HT7, but not at the control acupoint LI5, reduced the active lever responses on the reinstatement session, showing that HT7 suppressed craving for methamphetamine induced by reexposure to the drug during abstinence. And, the effects of acupuncture were blocked by the GABA receptors’ antagonists. In addition, HT7 did not influence saline self-administration, indicating that acupuncture effect was selective to the methamphetamine. Results of the present study show that acupuncture at HT7 suppresses reinstatement of methamphetamine self-administration behavior through the GABA receptor system without affecting the normal state. From the results, it may be suggested that acupuncture at HT7 can be a useful option in the treatment of methamphetamine addiction.

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