EFFECTS OF CLOZAPINE TREATMENT ON PLASMA BIOGENIC-AMINES IN ADOLESCENTS WITH SCHIZOPHRENIA

Longitudinal assessments (every six weeks for one year) were made of plasma norepinephrine, dopamine, epinephrine and 3-methoxy-4-hydroxyphenylglycol (MHPG) in 40 adolescents with schizophrenia, 20 on clozapine therapy and 20 on conventional medication. In addition to the plasma catecholamine determinations, serum levels of 5-HT were determined as a measure of serotoninergic status. All analyses were performed by HPLC-ECD (high-performance liquid chromatography with electrochemical detection). Clinical ratings of symptomatology were obtained with the Brief Psychiatric Rating Scale (BPRS) and the Andreasen scales for negative and positive symptoms (SANS and SAPS). Compared with the typical neuroleptic medication, clozapine administration was accompanied by a significant increase in plasma norepinephrine and MPHG and serum serotonin levels. The fluctuations in the biogenic amines were closely associated with the observed symptomatology. Plasma MHPG was linked to depressive symptoms (BPRS), and negative symptoms (SANS) were related to changes in the serum serotonin levels. The pathophysiological implications and clinical consequences of these findings are discussed.