title: Protein expression changes in the nucleus accumbens and amygdala of inbred alcohol-preferring rats given either continuous or scheduled access to ethanol.
abstract: Chronic ethanol (EtOH) drinking produces neuronal alterations within the limbic system. To investigate changes in protein expression levels associated with EtOH drinking, inbred alcohol-preferring (iP) rats were given one of three EtOH access conditions in their home-cages: continuous ethanol (CE: 24h/day, 7days/week access to EtOH), multiple scheduled access (MSA: four 1-h sessions during the dark cycle/day, 5 days/week) to EtOH, or remained EtOH-naïve. Both MSA and CE groups consumed between 6 and 6.5g of EtOH/kg/day after the 3rd week of access. On the first day of EtOH access for the seventh week, access was terminated at the end of the fourth MSA session for MSA rats and the corresponding time point (2300h) for CE rats. Ten h later, the rats were decapitated, brains extracted, the nucleus accumbens (NAcc) and amygdala (AMYG) microdissected, and protein isolated for 2-dimensional gel electrophoretic analyses. In the NAcc, MSA altered expression levels for 12 of the 14 identified proteins, compared with controls, with six of these proteins altered by CE access, as well. In the AMYG, CE access changed expression levels for 22 of the 27 identified proteins, compared with controls, with 8 of these proteins altered by MSA, as well. The proteins could be grouped into functional categories of chaperones, cytoskeleton, intracellular communication, membrane transport, metabolism, energy production, or neurotransmission. Overall, it appears that EtOH drinking and the conditions under which EtOH is consumed, differentially affect protein expression levels between the NAcc and AMYG. This may reflect differences in neuroanatomical and/or functional characteristics associated with EtOH self-administration and possibly withdrawal, between these two brain structures.
authors.affiliation: Institute of Psychiatric Research and Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN 46202, USA. ribell@iupui.edu
authors.forename: R L
authors.initials: RL
authors.lastname: Bell
authors.forename: M W
authors.initials: MW
authors.lastname: Kimpel
authors.forename: Z A
authors.initials: ZA
authors.lastname: Rodd
authors.forename: W N
authors.initials: WN
authors.lastname: Strother
authors.forename: F
authors.initials: F
authors.lastname: Bai
authors.forename: C L
authors.initials: CL
authors.lastname: Peper
authors.forename: R D
authors.initials: RD
authors.lastname: Mayfield
authors.forename: L
authors.initials: L
authors.lastname: Lumeng
authors.forename: D W
authors.initials: DW
authors.lastname: Crabb
authors.forename: W J
authors.initials: WJ
authors.lastname: McBride
authors.forename: F A
authors.initials: FA
authors.lastname: Witzmann
mesh_terms: D000428:Alcohol Drinking / Q000378:metabolism*; D000679:Amygdala / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002492:Central Nervous System Depressants / Q000008:administration & dosage* / Q000494:pharmacology; D003598:Cytoskeletal Proteins / Q000378:metabolism; D004334:Drug Administration Schedule; D015180:Electrophoresis, Gel, Two-Dimensional; D004798:Enzymes / Q000378:metabolism; D000431:Ethanol / Q000008:administration & dosage* / Q000494:pharmacology; D005260:Female; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism; D026901:Membrane Transport Proteins / Q000378:metabolism; D018832:Molecular Chaperones / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism*; D010449:Peptide Mapping; D011506:Proteins / Q000378:metabolism*; D040901:Proteomics / Q000379:methods; D051381:Rats; D011919:Rats, Inbred Strains; D012646:Self Administration; D013997:Time Factors
chemical_list: D015415:Biomarkers; D002492:Central Nervous System Depressants; D003598:Cytoskeletal Proteins; D004798:Enzymes; D047908:Intracellular Signaling Peptides and Proteins; D026901:Membrane Transport Proteins; D018832:Molecular Chaperones; D009419:Nerve Tissue Proteins; D011506:Proteins; D000431:Ethanol