This study investigated the response of central nervous system neurotensin systems to methamphetamine self-administration. Neurotensin levels decreased in rats during methamphetamine self-administration extinction when lever pressing resulted in intravenous infusion of saline rather than methamphetamine. The reductions in neurotensin levels in the anterior dorsal striatum particularly correlated with the lever pressing during the first session of extinction. Finally, the administration of a neurotensin receptor 1 (NTR1) agonist diminished lever pressing during the extinction session, whereas an NTR1 antagonist attenuated the reduction in lever pressing during the 2nd–4th days of extinction. In summary, these findings support the hypothesis that some of the endogenous basal ganglia neurotensin systems contribute to the elimination of contingent behavior during the early stages of the methamphetamine self-administration extinction process.
See article at J Pharmacol Exp Ther 2013, 346:173–181.
- Copyright © 2013 by The American Society for Pharmacology and Experimental Therapeutics