117— The Effects of Comorbid Alcohol and Cocaine Use on a Cognitive Maze Task

In U.S., 1 out of 4 adults reported binge drinking in the past month, a prevalence that increases to over 50% in college populations. Binge drinking is a common precursor for alcohol use disorder, and risk of polydrug use also increases.Cocaine is frequently used in combination with alcohol. Little is known about the history of binge drinking and comorbid cocaine influence on memory. We developed a mouse model of alcohol and cocaine co-use to investigate how comorbidity influences performance on a working memory task. We ran two groups of mice that differed in their history of alcohol use. Group 1 consisted of C57BL6/J male mice that were allowed to drink for 4 weeks (2hrs/day, 4x/week) and then were tested on the Barnes Maze (working memory task). After 1 more week of drinking, mice were again assessed for working memory following an injection of cocaine (20mg/kg, I.P.). Group 2 consisted of C57BL6/J male mice that did not drink alcohol and were assessed in the working memory task. After 1 week, they were retested in the task following an injection of cocaine. Comparisons were made across groups for differences in cognitive abilities following cocaine use that result from the co-use of alcohol

118— Environmental Enrichment as a Treatment for Cocaine Relapse

Cocaine addiction is a problem for millions of people, however we are still lacking an effective treatment. It is characterized by compulsive behaviour which marks difficulties in remaining abstinent, with a high risk of relapse. Here, I focus on the interaction between the post-drug environment and drug-seeking by testing one potential environmental treatment, an enriched environment (EE), to reduce risk of cocaine relapse. This study proposes to investigate neural circuits involved in environmental protection of context-induced relapse. Mice exposed to cocaine will be assessed for preference of a cocaine-associated context using the conditioned place preference (CPP) paradigm. Mice will then be housed in either standard or EE cages for 2 weeks of withdrawal, before being returned to the CPP chamber for a test of context-induced relapse. I hypothesize that EE will reduce cocaine relapse, an outcome associated with the changes in activation in brain regions related to reward and addiction

Childhood trauma and post-trauma environment affect fear memory and alcohol use differently in male and female mice

Background: Childhood trauma is associated with the development of adult mental health and substance use disorders, with females generally being more at risk. Alcohol is commonly used for coping with trauma, and alcohol use disorder (AUD) affects ~14.4 million adult Americans annually. Research investigating sex differences in the environmental modification of anxiety and alcohol use following childhood trauma will extend our understanding of the etiology of AUD. Here, we sought to model the interacting effects of a single-episode late childhood trauma with post-trauma environment on adult alcohol use using male and female mice. Methods: C57Bl6/J mice (d22) exposed to predator odor (TMT) or water were reared in standard environments (SE) or environmental enrichment (EE). Mice were assessed for adolescent anxiety and conditioned fear, and for adult alcohol use in a limited access, response non-contingent, alcohol exposure paradigm. Results: A single exposure to predator odor was an effective stressor, inducing long-term sex- dependent changes in conditioned fear and alcohol behaviors that interacted with post-trauma environment. Adolescent EE females showed more conditioned freezing to the trauma-associated context. Adult EE mice consumed less total alcohol than SE mice. However, alcohol use across time differed for males and females. Exposure to a childhood stressor increased alcohol use significantly in females, but not males. EE males, but not EE females, drank less than SE counterparts. Conclusions: Findings from this model recapitulate greater vulnerability to childhood trauma in females and support sex differences in post-trauma development of conditioned fear and alcohol use that are modified by environment

161— The effects of environment on the development of cocaine-seeking

Cocaine addiction is a major individual and societal issue. This study aimed to investigate the environmental and social factors that influence the development of cocaine addiction. Mice were reared in either standard housing or enriched housing. Cocaine preference was measured using the Conditioned Place Preference paradigm, in which subjects are conditioned to associate an injection of cocaine (20mg/kg. I.P.) with a particular side of a 3 chambered arena. Subjects reared in enriched environments displayed increased preference for cocaine in cue primed tests. All subjects displayed cocaine preference in cocaine primed tests. This may be attributed to the enhanced memory that is often seen in mice reared in enriched environments. Future neurobiological assessments will determine if differences exist in the activation patterns of brains from enriched and standard conditions which are associated with the underlying causes of behavior changes, e.g. hippocampus. These assessments will help to shed light on the neural mechanisms associated with cocaine addiction