니코틴 의존의 뇌 기전 및 약물 치료

Application of Neural Mechanisms in Pharmacotherapy of Nicotine Dependence

Cigarette smoking causes high rates of mortality and morbidity. Despite the efforts of many individuals to quit smoking, maintenance of long-term abstinence is difficult. Understanding the neural mechanisms of nicotine dependence is essential for the development of effective medications to maintain smokers’ abstinence. Nicotine may exert its motivational effects through direct actions on nicotinic acetylcholine receptors (nAchRs) containing the β2 subunit, located on dopamine neurons. Nicotine also modulates dopamine release indirectly by binding to nAchRs located on the excitatory glutamatergic and inhibitory γ-aminobutyric acid (GABA) neurons in the ventral teg-mental area. The initiation and maintenance of nicotine dependence usually occurs through positive/negative reinforcements, conditioning to various smoking cues, habituation/automatized processes, dysfunctional inhibitory systems, and neuroadaptations in the function of dopamine, glutamate, and GABA. Pharmacotherapies including varenicline, bupropion, or baclofen could facilitate smoking cessation via distinct neurobiological mechanisms of action. The appropriate use of pharmacotherapy is essential for the management of nicotine dependence.