CHRONIC ANTIDEPRESSANT DRUG-TREATMENT REDUCES TURNING BEHAVIOR AND INCREASES DOPAMINE LEVELS IN THE MEDIAL PREFRONTAL CORTEX

The effects of chronic administration of the antidepressant drugs desi pramine, nortryptiline and paroxetine (PAR) (10 mg/kg/day, 21 days) on changes in turning (circling) behavior and on norepinephrine (NE), do pamine (DA) and serotonin and their metabolites 3,4-dihydroxyphenylace tic acid and 5-hydroxyindole acetic acid (5-HIAA) in the medial prefro ntal cortex (PFC), nucleus accumbens and striatum were evaluated in ra ts. All three drugs eliminated turning biases in right turning rats. A ll drugs increased DA concentrations in the PFC while PAR increased NE in the PFC and reduced 5-HIAA in all three structures. The results ar e discussed with reference to previous findings involving brain asymme try in depression.