Increase of extracellular dopamine in prefrontal cortex of gerbils during acquisition of the avoidance strategy in the shuttle-box

We examined whether extracellular dopamine (DA) increase in medial prefront al cortex is correlated with the establishment or with the retrieval of an auditory avoidance strategy in a shuttle-box. Using microdialysis from righ t medial prefrontal cortex (mPFC) in combination with behavioral measures, gerbils were trained on a tone-footshock combination in two sessions on two successive days. Sessions in each animal involving avoidance strategy form ation and avoidance strategy retrieval were differentiated post hoc by usin g the percentage of conditioned responses (CR) and other behavioral measure s of training sessions. It was found that exclusively strategy formation co rrelated with high DA levels in mPFC. (C) 1999 Elsevier Science Ireland Ltd . All rights reserved.