COMPARISON OF SHORT-TERM ADMINISTRATION OF SERTINDOLE, CLOZAPINE AND HALOPERIDOL ON THE INACTIVATION OF MIDBRAIN DOPAMINE NEURONS IN THE RAT

The present study describes the effect of sertindole, clozapine and ha loperidol on the number of spontaneously active dopamine neurons in ve ntral tegmental area and substantia nigra pars compacta after daily or al treatment for 1, 2 or 3 weeks. In general, daily administration of high dosages (sertindole: 2.8 mumol/kg/day, clozapine: 60 mumol/kg/day , haloperidol: 0.43 mumol/kg/day) induced no statistically significant decrease in the number of active dopamine neurons within the first 2 weeks of treatment. All three compounds induced a marked effect in ven tral tegmental area after administration for 3 weeks, but only sertind ole and haloperidol influenced the activity in substantia nigra pars c ompacta. This result is in accordance with clinical data where the ant ipsychotic effect is observed after 2-3 weeks of treatment.