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Background: Accumulating evidence indicates that drug-related cues can induce dopamine (DA) release in the striatum of substance abusers. Whether these same cues provoke DA release in the human prefrontal cortex remains unknown. Methods: We used high-resolution positron emission tomography with [18F]fallypride to measure cortical and striatal DA D2/3 receptor availability in the presence versus absence of drug-related cues in volunteers with current cocaine dependence. Results: Twelve individuals participated in our study. Among participants reporting a craving response (9 of 12), exposure to the cocaine cues significantly decreased [18F]fallypride binding potential (BPND) values in the medial orbitofrontal cortex and striatum. In all 12 participants, individual differences in the magnitude of craving correlated with BPND changes in the medial orbitofrontal cortex, dorsolateral prefrontal cortex, anterior cingulate, and striatum. Consistent with the presence of autoreceptors on mesostriatal but not mesocortical DA cell bodies, midbrain BPND values were significantly correlated with changes in BPND within the striatum but not the cortex. The lower the midbrain D2 receptor levels, the greater the striatal change in BPND and self-reported craving. Limitations: Limitations of this study include its modest sample size, with only 2 female participants. Newer tracers might have greater sensitivity to cortical DA release. Conclusion: In people with cocaine use disorders, the presentation of drug-related cues induces DA release within cortical and striatal regions. Both effects are associated with craving, but only the latter is regulated by midbrain autoreceptors. Together, the results suggest that cortical and subcortical DA responses might both influence drug-focused incentive motivational states, but with separate regulatory mechanisms. [ABSTRACT FROM AUTHOR]

Information about topics discussed at the 30th Annual Meeting of the Canadian College of Neuropsychopharmacology (CCNP) that was held in Banff, Alberta on June 15 to June 19, 2007 is presented. Such symposium highlighted the grant of 2007 Heinz Lehmann Award to Hymie Anisman. Further, such symposium featured the participation of several health personnel including Nicholas Barden.

The article highlights the 29th Annual Meeting of the Canadian College of Neuropsychopharmacology (CCNP) held in Chicago, Illinois on July 9-13, 2006. Dr. Rachel Tyndale received the 2006 CCNP Innovations Award lecture, while Dr. Stan Floresco accepted the 2006 CCNP Young Investigator Award lecture. The topics of research discussed include the molecular genetics of neurodevelopmental factors for schizophrenia and treatments and assessment tools for female-specific mood disorders.