Music therapy inhibits morphine-seeking behavior via GABA receptor and attenuates anxiety-like behavior induced by extinction from chronic morphine use.

RATIONALE: Morphine is a representative pain killer. However, repeated use tends to induce addiction. Music therapy has been gaining interest as a useful type of therapy for neuropsychiatric diseases.

OBJECTIVES: The present study examined whether Korean traditional music (KT) could suppress morphine-seeking behavior and anxiety-like behavior induced by extinction from chronic morphine use and additionally investigated a possible neuronal mechanism.

MATERIAL & METHODS: Male Sprague-Dawley rats were trained to intravenously self-administer morphine hydrochloride (1.0 mg/kg) using a fixed ratio 1 schedule in daily 2 h session during 3 weeks. After training, rats who established baseline (variation less than 20% of the mean of infusion for 3 consecutive days) underwent extinction. Music was played twice a day during extinction. In the second experiment, the selective antagonists of GABAA and GABAB receptors were treated before the last playing to investigate the neuronal mechanism focusing on the GABA receptor pathway. Another experiment of elevated plus maze was performed to investigate whether music therapy has an anxiolytic effect at the extinction phase.

RESULTS: KT but not other music (Indian road or rock music) reduced morphine-seeking behavior induced by a priming challenge with morphine. And, this effect was blocked by the GABA receptor antagonists. In addition, KT showed anxiolytic effects against withdrawal from morphine.

CONCLUSIONS: Results of this study suggest that KT suppresses morphine-seeking behavior via GABA receptor pathway. In addition, KT showed to have anxiolytic effects, suggesting it has bi-directional effects on morphine.