AN EXAMINATION OF DEVELOPMENTAL AND SEX DIFFERENCES IN ETHANOL CONSUMPTION BY LOW ALCOHOL-CONSUMING RAT LINES

Abstract

In the United States, alcohol use and dependence is a major health issue affecting 4-5% of the population (Hasin et al., 2007). Research indicates ad-olescents ages 12-20 drink 11% of all alcohol consumed nationally, with more than 90% consumed in the form of binge drinking (Center for Disease Control and Prevention, 2010). Similar to the human condition, adolescent rodents generally consume more ethanol than their adult counterparts. Current rat animal model studies on alcoholism remain weighted toward examining Family History Positive (FHP), selectively bred, alcohol-preferring lines. Also, research has generally been focused on ethanol consumption be-havior of male rodents. However, female rodents tend to consume more al-cohol than male rodents (e.g., Adams et al., 1991). In addition, existing re-search on adolescent vs. adult alcohol abuse using “FHP” rats is not paral-leled by research with “Family History Negative” (FHN) rats, which might re-veal factors that prevent/protect an individual from excessive ethanol intake during this crucial stage of development. The purpose of this study was to evaluate ethanol consumption by male and female FHN, selectively bred, alcohol-nonpreferring rats during adoles-cence and adulthood. Studying adolescent vs. adult behavior may reveal de-velopmentally-specific, protective factors. Also, examining male versus fe-male behavior may reveal sex-by-development factors guarding against al-cohol abuse. Animals were placed in cages and assigned to experimental conditions defined by the following independent variables: line of rodent, rodent’s sex and age of ethanol exposure. The following dependent measures were exam-ined: changes in body weight as well as water and ethanol consumption. These measures were taken at least 5 days per week. We hypothesized that there would be elevated levels of ethanol con-sumption (g ethanol/kg body weight/day) in (a) adolescent vs. adult rats and (b) female vs. male rats. Future research might focus on gene and/or protein expression differences within certain nuclei of the brain’s reward neurocircuit between the FHP and FHN lines of rats. Currently, some data has been collected and statistically analyzed. Upon completion the study re-sults will be prepared for presentation and manuscript submission. Funded in part by the Indiana University-Purdue University Indianapolis, Undergraduate Re-search Opportunities Program (UROP)