Extracellular glutamate decrease in accumbens following cued food delivery

This study examined the effects of cued vs non-cued food delivery/consumption on extracellular glutamate and dopamine in the nucleus accumbens of food-deprived rats. Animals that always received a food pellet following a series of auditory tones showed a significant decrease in extracellular glutamate following food consumption, whereas animals that had not been previously exposed to tone-food pairing did not (p < 0.05). In contrast, extracellular dopamine was significantly increased in the nucleus accumbens during the first time period after food consumption (p < 0.05) regardless of whether animals had been exposed to prior tone-food pairing. Results suggest that food delivery/consumption is associated with a decrease in accumbal glutamate if food delivery has been previously paired with predictive environmental cues.