Age-related effects of chronic restraint stress on ethanol drinking, ethanol-induced sedation, and on basal and stress-induced anxiety response

FERNÁNDEZ, MACARENA SOLEDAD; MIRIAM B VIRGOLINI; ARANZA WILLE-BILLE ; PAUTASSI, RICARDO MARCOS; FABIO, MARIA CAROLINA; LAURA N DE GIOVANNI; NIZHNIKOV, MICHAEL E.; ROBERTO SEBASTIÁN MIRANDA-MORALES; CRISTIAN HANSEN ; LINDA SPEAR

ALCOHOL

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 2016 vol. 51 p. 89 - 100

0741-8329

Adolescents are sensitive to the anxiolytic effect of ethanol, and evidence suggests that they may be more sensitive to stress than adults. Relatively little is known, however, about age-related differences in stress modulation of ethanol drinking or stress modulation of ethanol-induced sedation and hypnosis. We observed that the chronic restraint stress transiently exacerbated free-choice ethanol drinking in adolescent, but not in adult rats. Restraint stress altered exploration patterns of a light dark box apparatus in adolescents and adults. Stressed animals spent significantly more time in the white area of the maze and made significantly more transfers between compartments than their non-stressed peers. Behavioral response to acute stress, on the other hand, was modulated by prior restraint stress only in adults. Adolescents, unlike adults, exhibited ethanol-induced motor stimulation in an open field. Stress increased the latency to loss the righting reflex after a high ethanol dose, yet this effect was similar at both ages. Ethanol-induced sleep time was much higher in adults than in adolescent rats, yet stress diminished ethanol-induced sleep time only in adults. The study indicates age-related differences that may increase the risk for initiation and escalation in alcohol drinking.