Chronic and passive alcohol administration induces ΔFosB expression in mesocorticolimbic brain areas in adolescent and adult rats.

WILLE-BILLE, ARANZA; GODINO A.; PAUTASSI R.M.

Virtual

Congreso; XXXV Congreso Anual (Virtual) de la Sociedad Argentina de Neurociencias.; 2020

Sociedad Argentina de Neurociencias

IntroductionFigure 1. ΔFosB immunoreative cells, in Prelimbic Cortex (PrL), NucleusAccumbens Core (AcbC) and Shell (AcbSh), Dorsolateral (DLS) andDorsomedial (DMS) Striatum, Basolateral Amygdala (BLA) and CentralAmygdala nucleus Capsular (CeC) of adolescent and adults rats,administered with vehicle (W), escalating (ESC) or constant (CTE) dosesof alcohol, during 18 sessions. Asterisks indicate significant differencesbetween the groups administered with alcohol and vehicle group. Thedata are expressed as the number of ΔFosB-ir cells per 0.04 mm2. Datawere collapsed across sex. Vertical bars represent the SEM.Materials and MethodsResultsChronic and passive alcohol administrationinduces ΔFosB expression in mesocorticolimbicbrain areas in adolescent and adult rats.Wille-Bille, Aranza1; Godino, Andrea1,2; Pautassi, Ricardo1,2Instituto de Investigaciones Médicas Mercedes y Martín Ferreyra (INIMECCONICET-UNC) Córdoba, Argentina.Facoltad de Psicología, Universidad Nacional de Córdoba; Córdoba, Argentina.1 2During adolescence, alcohol drinking normativelybegins and escalates. We have shown that adolescentrats consumed less alcohol than adults, and exhibiteda progressive increase in alcohol intake, whereasadults exhibited a stable pattern (Wille-Bille et al.,2017). This escalating pattern of alcohol selfadministration enhanced the induction of ∆FosBexpression in several mesocorticolimbic areas of theadolescent brain, whereas alcohol drinking in theadults did not alter expression of ∆FosB.We aimed to assess if ΔFosB induction wasdependent on an escalating pattern of alcoholexposure, rather than in the volume of exposure.Adolescent and adult rats were intermittentlyadministrated with vehicle, escalating (0.5- 2.5 g/kg)or high, constant (2.0 g/kg) doses of alcohol, during18 sessions, through intragastric intubation. Seventytwo hours after the last administration, ΔFosB wasquantified in several mesocorticolimbic areas, byimmunohistochemistry.Both alcohol patterns significantly increased ΔFosBlevels, similarly in adolescent and adult rats (Fig. 1).The constant doses exacerbated ΔFosB in all brainareas but in Central Nucleus of Amygdala, whereasthe escalating doses induced ΔFosB expression inPrelimbic Cortex and Basolateral Amygdala (Fig. 2).ConclusionThis study showed that chronic and passive alcoholexposure induces ΔFosB in brain areas involved inreward processing, in adolescent and adults.Figure 2. Representative photomicrographs (10x) of ΔFosB-immunoreactive (ΔFosB-ir) cells in Prelimbic Cortex (PrL), Basolateral Amygdala(BLA), Nucleus Accumbens Core (AcbC) and Shell (AcbSh), Dorsolateral (DLS) and Dorsomedial (DMS) Striatum in adolescent and adult rats,administered with vehicle (W), escalating (ESC) or constant (CTE) doses of alcohol, during 18 sessions. Scale bar = 100 µm.