The treatment of chronic pain with traditional methods such as drug, acupuncture therapy or sympathetectomy has many unresolvable side effects and complications, especially the tolerance and dependence for long-period drug delivery that could cause the ineffectiveness of the treatment. 慢性疼痛的形成机理极其复杂,现有的治疗手段如药物治疗、针灸治疗和交感神经切除术的远期效果差,并且长期应用阿片类药物还易产生依赖和耐受等副作用。