Voluntary ethanol consumption patterns as a function of inborn anxiety and restraint-induced stress in adolescent rats.

ACEVEDO MB; SPEAR, N.E.; PAUTASSI RM

Concepción

Workshop; First Joint Meeting on Alcohol and other Drugs of Abuse: from molecules to human disorders; 2013

Latin American Society for Biomedical Research on Alcoholism andLatin American Research Network in Drug Abuse

Aim: To analyze if restraint-induced stress and basal levels of inborn anxiety affect ethanol intake in heterogeneous adolescent female Wistar rats. Methods: At postnatal day (PD) 28 animals were screened for anxiety through an elevated plus maze (EPM) and light-dark box (LDB) tests. The percent of the open arm entries in the EPM and the latency to enter from the brightly lit into the dark compartment of the box (LDB) were employed to generate a single measure of anxiety response. A split procedure was conducted on this variable and adolescents were divided as lowanxiety, average-anxiety and high-anxiety responders (LA, AA and HA groups, respectively). Animals were then given intermittent-access to 5% ethanol and vehicle (three 18-h sessions per week) during four weeks from PD32-57. During the first two weeks (session 1-6) ethanol was mixed with low-concentrated sucrose, whereas in weeks 3 and 4 (sessions 7-12) animals were given ethanol without sweetener. Results: From session 7 to session 12, high-anxiety responders exhibited significantly higher ethanol intake than counterparts with average levels of anxiety, but only when not exposed to stress. HA subjects not exposed to stress exhibited a two-fold increase in g/kg of ethanol consumed and a three-fold increase in percent ethanol intake, when compared with control animals. These results suggest that high levels of inborn anxiety may predispose animals to ingest ethanol during adolescence.