Cross-sensitization between cocaine and acute restraint stress is associated with sensitizec dopamine but not glutamate release in the nucleus accumbens

GARCIA KELLER, C; MARTINEZ, S; EZPARZA A; BOLLATI F; KALIVAS PW; CANCELA LM

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2013 vol. 36 p. 3103 - 3103

p>Repeated administration of psychostimulant drugs or stress can elicit a sensitized response to the stimulating and reinforcing properties of the drug. Here we explore the mechanisms in the nucleus accumbens (NAc) whereby an acute restraint stress augments the acute locomotor response to cocaine. This was accomplished by a combination of behavioral pharmacology, microdialysis measures of extracellular dopamine and glutamate, and Western blotting for GluR1 subunit of the á-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptor (AMPAR). A single exposure to restraint stress 3 weeks before testing revealed that enduring locomotor sensitization to cocaine was paralleled by an increase in extracellular dopamine in the core, but not the shell subcompartment, of the NAc. Wistar rats pre-exposed to acute stress showed increased basal levels of glutamate in the core, but the increase in glutamate by acute cocaine was blunted. The alterations in extracellular glutamate se