The general objective of this project is to explore the neurobiological mechanisms responsible for the escalation and maintenance of ethanol self-administration. Current theories of addiction posit that long-term ethanol self-administration becomes a habit-based, rather that goal-oriented, behavior. Neuroplasticity in the dorsolateral striatum is thought to be necessary for the expression of habitual behavior, and recent research implicates the endocannabinoid system in both habit formation and in several forms of striatal plasticity. Thus, the overarching hypothesis of this proposal is that the maintenance of long-term ethanol self-administration is a habit-based behavior mediated, at least in part, by endocannabinoid signaling in the dorsolateral striatum. This hypothesis will be tested in the two specific aims of the present application.
The first aim will measure the effect of operant ethanol self-administration by Long Evans rats on extracellular levels of the two endocannabinoids anandamide and 2-AG, as measured by in vivo microdialysis, in the dorsolateral striatum.
The second aim will examine the involvement of the cannabinoid CB1 receptor during the expression of habitual operant ethanol self-administration in Long Evans rats. After establishing self- administration of ethanol, rats will receive infusions of the CB1 receptor antagonist rimonabant into the dorsolateral striatum to determine the involvement of these receptors in self-administration behavior. Together, the results of these experiments should increase the understanding of the role of the endocannabinoid system in habitual ethanol self-administration, and contribute new information regarding the mechanisms that underlie the maintenance of habitual self-administration of alcohol. Public health relevance: The present study aims to investigate neurobiological mechanisms underlying the development and maintenance of behaviors involved in alcohol addiction. The information gained from this research will lead to a better understanding the brain changes that occur as chronic alcohol use develops, and could be used to develop more effective treatments for alcohol addiction.

Agency
National Institute of Health (NIH)
Institute
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Type
Postdoctoral Individual National Research Service Award (F32)
Project #
5F32AA018252-02
Application #
7942839
Study Section
Health Services Research Review Subcommittee (AA)
Program Officer
Grakalic, Ivana
Project Start
2009-05-01
Project End
2011-04-30
Budget Start
2010-05-01
Budget End
2011-04-30
Support Year
2
Fiscal Year
2010
Total Cost
$50,474
Indirect Cost
Name
University of Texas Austin
Department
Pharmacology
Type
Schools of Pharmacy
DUNS #
170230239
City
Austin
State
TX
Country
United States
Zip Code
78712
Vena, Ashley A; Mangieri, Regina; Gonzales, Rueben A (2016) Regional Analysis of the Pharmacological Effects of Acute Ethanol on Extracellular Striatal Dopamine Activity. Alcohol Clin Exp Res 40:2528-2536
Mangieri, Regina A; Cofresí, Roberto U; Gonzales, Rueben A (2014) Ethanol exposure interacts with training conditions to influence behavioral adaptation to a negative instrumental contingency. Front Behav Neurosci 8:220
Valenta, John P; Job, Martin O; Mangieri, Regina A et al. (2013) ?-opioid receptors in the stimulation of mesolimbic dopamine activity by ethanol and morphine in Long-Evans rats: a delayed effect of ethanol. Psychopharmacology (Berl) 228:389-400
Mangieri, Regina A; Cofresí, Roberto U; Gonzales, Rueben A (2012) Ethanol seeking by Long Evans rats is not always a goal-directed behavior. PLoS One 7:e42886