Cholecystokinin 25 (CCK25)

Since its discovery in the brain, anatomical, physiological and pharmacological research on cholecystokinin (CCK) and its possible involvement in neurological and psychiatric disease has continued unabated. In just the last three years, over 1400 papers have been published on CCK. Much of this excitement has to do with CCK's colocalization with dopamine and its ability to modulate mesolimbic, mesocortical and nigral striatal dopaminergic neurotransmission. The presence of abundant CCK in the cortex and hippocampus colocalized with GABA and the CCK projection from prefrontal cortex to striatum has additional implications for a possible role in anxiety, attention deficit disorder, and in the negative symptoms and cognitive deficits of schizophrenia. This review will attempt to integrate this large body of knowledge (while providing only selective references) and point out future directions of investigation.