Effects of Voluntary Access to Sweetened Ethanol During Adolescence on Intake in Adulthood

Background: The prevalence of alcohol use during adolescence is concerning given that early age of alcohol initiation is correlated with the development of alcohol-related problems later in life. The purpose of this series of studies was to assess whether voluntary ethanol (EtOH) exposure during adolescence would influence EtOH drinking behavior in adulthood using an animal model.

Methods: Pair-housed Sprague-Dawley adolescent (postnatal day [P] 28 to 42) rats of both sexes were given single bottle access to 1 of 3 solutions in their home cages-10% EtOH in "supersac" (0.125% saccharin and 3% sucrose) (EtOH/SS), supersac without EtOH (SS), or water-for 30 minutes every other day for a total of 8 drinking days or were left nonmanipulated (NM). Animals were NM thereafter until adulthood (P70) at which time they were given 1-bottle, 30 minute limited access tests with 20% EtOH every other day (Exp 1), 10% EtOH in SS (Exp 2), or SS without EtOH (Exp 3).

Results: Adolescent EtOH/SS exposure increased adulthood consumption of EtOH/SS (Exp 2), but not 20% unsweetened EtOH (Exp 1) or SS (Exp 3), with this increase most pronounced at the beginning of the 8 intake day procedure. Access to SS (without EtOH) during adolescence produced an analogous effect, with increased adult SS consumption during the first 2 intake days, but no increases in either of the EtOH test solutions.

Conclusions: Solution-specific increases in adulthood intake after adolescent exposure are most likely associated with solution acceptance due to familiarity. This is an important consideration for future intake studies assessing the influence of EtOH exposure during adolescence on intake of EtOH in adulthood.