AGE-RELATED EFFECTS OF RESTRAINT STRESS ON ETHANOL INTAKE

WILLE-BILLE, ARANZA; FERREYRA, A.; SCIANGULA, M.; PAUTASSI R.M.

Volterra

Congreso; Fourth International Congress on Alcoholism and Stress: A Framework for Future Treatment Strategies; 2017

Several work has suggested that adolescents may be significantly moresensitive to stress, and to ethanol-stress interactions, than adults. It is thusimportant to analyze stress-reactive drinking during adolescence andpotential treatments to ameliorate it. Stress effects upon ethanol intake inanimal rat models have been controversial, with studies indicatingheightened, decreased or unaltered ethanol intake after stress. The presentstudy analyzed the impact of chronic restraint stress (5 daily, 2h long,sessions) upon ethanol intake, assessed across two-weeks via intermittent,18-h two bottle intake tests, in male and female adolescent and adult rats.We found greater ethanol intake and preference in stressed than in nonstressedfemale, but not in male, adolescent rats. This effect of stress wasinhibited after blockade of kappa opioid receptors by norbinaltorphimine(10 mg/kg). Significant age-related differences were observed, withstressed-adult females drinking actually less than their same-age controls.In subsequent experiments we observed that adolescent stressed femalesexhibited signs of behavioral disinhibition when tested in a modifiedversion of the concentric square field test. Altogether, these results confirmthe hypothesis of greater adolescent reactivity to stress, which can result inincreased liability for ethanol intake, particularly among females. Treatments that tackle the endogenous opioid system, in particular thekappa receptors, seem to hold promise as a therapeutic target to reducethis stress-mediated ethanol drinking. Financial sources: PIP CONICET2013, PICT 2012 and FFF grant 2016.