Authors: R E See J C Elliott M W Feltenstein
Publish Date: 2007/06/24
Volume: 194, Issue: 3, Pages: 321-331
Abstract
Rats selfadministered cocaine for 2 h/day for ten sessions followed by 2 weeks of abstinence ie no extinction training Immediately before being returned to the selfadministration chamber we assessed the effects of gammaaminobutyric acid agonist inhibition of midbrain DA regions substantia nigra SN and ventral tegmental area VTA and striatum dorsolateral caudate–putamen nucleus accumbens core and nucleus accumbens shell on relapse to cocaineseeking in the absence of reinforcement Further testing examined daily extinction responding subsequent to the initial relapse testInactivation of the dorsal caudate–putamen and midbrain regions attenuated cocaine seeking while inactivation of the ventral striatum had no such effects However subsequent sessions under extinction conditions revealed a rebound in cocaine seeking in animals that had undergone inactivation in all regions except the dorsolateral caudate–putamenThe dorsal but not ventral striatum plays a critical role in cocaine seeking immediately after abstinence These data support the theory that chronic cocaine may shift activity from the ventral to dorsal striatum during drug seeking under certain conditions While not necessary at the time of relapse the ventral striatum appears to be involved in processing critical information of the relapse event
Keywords: