Impairment of glutamate homeostasis in the nucleus accumbens core underpins cross-sensitization to cocaine following chronic restraint stress

AVALOS, MARÍA P.; GUZMAN, ANDREA S.; GARCIA-KELLER, CONSTANZA; MONGI-BRAGATO, BETHANIA; ESPARZA, MARÍA A.; RIGONI, DAIANA; SANCHEZ, MARIANELA A.; CALFA, GASTÓN D.; BOLLATI, FLAVIA A.; CANCELA, LILIANA M.

Frontiers in Physiology

Frontiers Media S.A.

Año: 2022 vol. 13

hough the facilitating influence of stress on drug abuse is well documented, the mechanisms underlying this interaction have yet to be fully elucidated. The present study explores the neurobiological mechanisms underpinning the sensitized response to the psychomotor-stimulating effects of cocaine following chronic restraint stress (CRS), emphasizing the differential contribution of both subcompartments of the nucleus accumbens (NA), the core (NAcore) and shell (NAshell), to this phenomenon. Adult male Wistar rats were restrained for 2 h/day for 7 days and, 2 weeks after the last stress exposure (day 21), all animals were randomly assigned to behavioral, biochemical or neurochemical tests. Our results demonstrated that the enduring CRS-induced increase in psychostimulant response to cocaine was paralleled by an increase of extracellular dopamine levels in the NAcore, but not the NAshell, greater than that observed in the non-stress group. Furthermore, we found that CRS induced an impai