Conditioning the neuroimmune response to ethanol using taste and environmental cues in adolescent and adult rats

ANNY GANO; PAUTASSI R.M.; TAMARA DOREMUS-FITZWATER; BARNEY, R.M.; VORE, A.S.; TERRENCE DEAK

EXPERIMENTAL BIOLOGY AND MEDICINE

SOC EXPERIMENTAL BIOLOGY MEDICINE

Lugar: Maywood; Año: 2019 vol. 244 p. 362 - 371

1535-3702

Our work in adult Sprague-Dawley rats has shown elevation of thecytokine Interleukin (IL)-6 in the hippocampus and amygdala followingacute and repeated binge-like doses of ethanol during intoxication.Previously, we have shown that in adults, the central IL-6 response to asub-threshold dose of ethanol was sensitized by repeated pairings ofethanol as an unconditioned stimulus (US) with an odor conditionedstimulus (CS). In the present studies, acute ethanol exposure (4 g/kgi.p.) was paired with a combined odor and taste cue using a single triallearning procedure, after which rats were tested for conditioned effectsof the CS on neuroimmune gene expression. We found that IL-6 wassignificantly elevated in the amygdala based on exposure to the CS afterjust one CS-US pairing in young adolescent rats (age P32-40), an effectthat approached but did not achieve significance in young adults (P72-80). These data indicate that, despite a normal disposition toward ablunted neuroimmune response to ethanol, adolescents were moresensitive than adults to forming learned associations between ethanol?sneuroimmune effects and conditioned stimuli. Given the emergent role ofthe immune system in alcoholism, such as regulating ethanol intake,these ethanol-induced conditioned effects on cytokine levels maycontribute to our understanding of the unique attributes that makeadolescence a time period of vulnerability in the development of lateralcohol abuse behaviors.