Amygdala central role

The shell of the nucleus accumbens, the bed nucleus of the stria terminalis, and the central nucleus of the amygdala, together referred to as the extended amygdala, may play a role in diug addiction. 

Extrahypothalamic OX-B-like immunoreactivity, reminiscent to that of CRF, has been described in clustered GABAergic neuronal populations, in the lateral division of central nucleus ofthe amygdala, the bednucleus of the stria terminalis, and in the hippocampus. Moreover, ectopic expression of preproorexin mRNA in the gut, ependymal cells, neuroblastomas, and of orexin receptors in adrenal gland, cancer and hematopietic stem cells suggests yet unexplored roles of orexins as paracrine factors controlling blood-brain barrier, and tumor or stem cell function. 

Baum, M. J. and Everitt, B. J. (1992) Increased expression of c-fos in the medial preoptic area after mating in male rats role of afferent inputs from the medial amygdala and midbrain central tegmental field. Neuroscience 50, 627-646. 

Recent microdialysis studies show that DA transmission in the bed nucleus of stria terminalis (BNST) is activated by drugs of abuse as efficiently as in the NAc shell (Carboni et al., 2000). The role of this effect in the reinforcing and addictive properties of drugs is unknown. The central amygdala is an area related to the BNST. Local infusion of a D1 antagonist (SCH 23390) in this area impairs cocaine self-administration (Caine et al., 1995). 

Parkinson JA, Robbins TW, Everitt BJ (2000) Dissociable roles of the central and basolateral amygdala in appetitive emotional learning. Europ. J. Neuroscience 72 405-413. 

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