Monoamine oxidase and tobacco dependence.

Tobacco smoking is a leading cause of preventable death around the world, and there are major public health and research efforts in many countries aimed at reducing its usage. However, the molecular mechanisms underlying tobacco dependence are still not completely understood. Nicotine's action on nicotinic acetylcholine receptors, and the downstream release of dopamine, is believed to be the major pathway underlying tobacco dependence. However there is mounting evidence indicating that non-nicotinic components of tobacco smoke also play a role by inhibiting monoamine oxidase (MAO) and subsequently altering neurotransmitter levels. This article provides a review of the current knowledge of the association between MAO and tobacco dependence and suggests that further research into this topic is likely to lead to more effective pharmacotherapies for smoking cessation.