Differential changes in DOPAC levels in the hippocampal formation, septum and striatum of the rat induced by acute and repeated neuroleptic treatment.

Acute administration of haloperidol, sulpiride and chlorpromazine produces an elevation of hippocampal, septal and striatal DOPAC levels. The ED50 of haloperidol is similar in all areas but the maximal effect is much lower in the hippocampal formation than in septum and striatum. Repeated administration (11 days) of haloperidol causes a less pronounced increase (tolerance) in DOPAC levels in all regions investigated than acute treatment, the hippocampal formation being the most susceptible to this tolerance.