Reversal of dopamine inhibition of dopaminergic neurons of the ventral tegmental area is mediated by protein kinase C.

ABSTRACT: Adaptation of putative dopaminergic (pDA) neurons in the ventral tegmental area (VTA) to drugs of abuse may alter information processing related to reward and reinforcement and is an important factor in the development of addiction. We have demonstrated that prolonged increases in the concentration of dopamine (DA) result in a time-dependent decrease in sensitivity of pDA neurons to DA, which we termed DA inhibition reversal (DIR). In this study, we used extracellular recordings to examine factors mediating DIR. A 40 min administration of DA (2.5-10 μM), but not the DA D2 receptor agonist quinpirole (50-200 nM), resulted in inhibition of neuronal firing followed by DIR. In the presence of 100 nM cocaine, inhibition followed by DIR was seen with much lower DA concentrations. Reversal of qui

SUBMITTER: Nimitvilai S 

PROVIDER: S-EPMC3242316 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature