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

CANCELA LILIANA M

Frontiers in Physiology

Frontiers SA

Año: 2022

1664-1078

hough the facilitating influence of stress on drug abuse is well documented, the mechanisms underlying this interaction have yetto be fully elucidated. The present study explores the neurobiological mechanisms underpinning the sensitized response to thepsychomotor-stimulating effects of cocaine following chronic restraint stress (CRS), emphasizing the differential contribution ofboth subcompartments of the nucleus accumbens (NA), the core (NAcore) and shell (NAshell), to this phenomenon. Adult male Wistar rats were restrained for 2 hours/day for seven days and, two 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 a