Stimuli Linked to Ethanol Availability Activate Hypothalamic CART and Orexin Neurons in a Reinstatement Model of Relapse
Biological Psychiatry, In Press Corrected Proof, Available online 14 June 2007



There has been a recent upsurge of interest in the role of hypothalamic feeding peptides, in particular, orexin (hypocretin), in drug-seeking behavior. However, the potential role of other hypothalamic feeding peptides, such as cocaine- and amphetamine-regulated transcript (CART), in conditioned reinstatement has yet to be explored.

Significantly larger numbers of Fos-positive arcuate nucleus CART and hypothalamic orexin neurons were seen in animals exposed to the EtOH S+ compared with nonreward S− animals. Presentation of the EtOH S+ also increased numbers of Fos-positive PVT neurons. Fos-positive PVT neurons were observed to be closely associated with orexin and CART terminal fields.

Taken together, these findings suggest that activation of hypothalamic neuropeptide systems may be a common mechanism underlying drug-seeking behavior.

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Reprint Request E-Mail: Christopher.Dayas@newcastle.edu.au

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