Open AccessSelf-Administration of Ethanol, Cocaine, or Nicotine Does Not Decrease the Soma Size of Ventral Tegmental Area Dopamine Neurons
Author(s) -
Michelle S. MazeiRobison,
Raghu Appasani,
Scott Edwards,
Sunmee Wee,
Seth R. Taylor,
Marina R. Picciotto,
George F. Koob,
Eric J. Nestler
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0095962
Subject(s) - ventral tegmental area , dopamine , nicotine , opiate , neuroscience , neuroplasticity , soma , nucleus accumbens , self administration , pharmacology , dopaminergic , mesolimbic pathway , medicine , biology , receptor
Our previous observations show that chronic opiate administration, including self-administration, decrease the soma size of dopamine (DA) neurons in the ventral tegmental area (VTA) of rodents and humans, a morphological change correlated with increased firing rate and reward tolerance. Given that a general hallmark of drugs of abuse is to increase activity of the mesolimbic DA circuit, we sought to determine whether additional drug classes produced a similar morphological change. Sections containing VTA were obtained from rats that self-administered cocaine or ethanol and from mice that consumed nicotine. In contrast to opiates, we found no change in VTA DA soma size induced by any of these other drugs. These data suggest that VTA morphological changes are induced in a drug-specific manner and reinforce recent findings that some changes in mesolimbic signaling and neuroplasticity are drug-class dependent.