Is dopamine important in nicotine dependence?

Nicotine, like other drugs when abused, can produce a wide array of behaviours, some of which collectively propel 'drug-seeking behaviour'. This review focuses on three stimulus properties of nicotine and examines the role of dopamine in mediating each effect with respect to D1 and D2 receptor subtypes. Dopamine appears to be critical in mediating the reinforcing effects of nicotine, which is in line with other commonly abused psychomotor stimulants. However, evidence derived from studies with local microinjections of nicotine suggests that the origin of nicotine action to produce its other stimulus properties may be via multiple neuroanatomical substrates. The aversive stimulus effects are resistant to dopamine receptor antagonists. The discriminative stimulus effects of nicotine, despite showing some modification with dopaminergic compounds, appear not to be solely mediated via the mesolimbic dopamine system. Taken together, the neurobiology of nicotine dependence remains complex. Nonetheless, such dissociation between stimulus properties may permit the development of more effective therapies in combating tobacco dependence.