title: Comparison of ethanol locomotor sensitization in adolescent and adult DBA/2J mice.
abstract: BACKGROUND
  The mammalian adolescent period is characterized by enhanced vulnerability to drug-induced neuroadaptations. Epidemiological evidence indicates that individuals who start drinking alcohol during adolescence are four times more likely to develop alcohol dependence in adulthood, but little is known about the adaptive mechanism(s) that may underlie this observation. Behavioral sensitization in rodents is a model of neurobehavioral plasticity that occurs following repeated drug exposure and may underlie components of addiction.
  
  
  OBJECTIVE
  The goal of this study was to determine if adolescent mice are differentially sensitive to ethanol-induced locomotor sensitization as compared to adults.
  
  
  METHODS
  Adolescent and adult DBA/2J mice were treated with saline or ethanol (1.0, 1.5, 2.0, 2.5 g/kg) for 7, 11, or 15 days and tested for acute and sensitized locomotor activity. Blood ethanol clearance (BEC) was also assessed 10, 60, and 180 min following treatment with ethanol 2 g/kg.
  
  
  RESULTS
  Adolescent mice were more sensitive than adult mice to the acute locomotor activating effects of ethanol. However, adolescent mice were less sensitive than adult mice to locomotor sensitization, as only the highest dose of ethanol (2.5 g/kg) induced sensitization in the adolescent mice, while lower doses of ethanol elicited sensitization in the adult mice. The differential response to ethanol sensitization was not related to duration of treatment or differential BEC.
  
  
  CONCLUSIONS
  These results indicate that adolescent mice are less sensitive to ethanol sensitization, and this blunted behavioral response in adolescents might reflect differential ethanol-induced neurobehavioral adaptations.
authors.affiliation: Bowles Center for Alcohol Studies, Department of Psychiatry, Curriculum in Neurobiology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
authors.forename: Rebekah A
authors.initials: RA
authors.lastname: Stevenson
authors.forename: Joyce
authors.initials: J
authors.lastname: Besheer
authors.forename: Clyde W
authors.initials: CW
authors.lastname: Hodge
mesh_terms: D000367:Age Factors; D000818:Animals; D001143:Arousal / Q000187:drug effects; D001921:Brain / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000097:blood / Q000633:toxicity*; D007274:Injections, Intraperitoneal; D008297:Male; D008657:Metabolic Clearance Rate / Q000502:physiology; D051379:Mice; D008811:Mice, Inbred DBA; D009043:Motor Activity / Q000187:drug effects*; D009473:Neuronal Plasticity / Q000187:drug effects
chemical_list: D000431:Ethanol