HYPERDOPAMINERGIA IN SCHIZOPHRENIFORM PSYCHOSIS - A CHRONOBIOLOGICAL STUDY

Circadian rhythm abnormalities have been described in various psychiat ric disorders, but they have not received much attention in studies of schizophrenia and schizophreniform psychosis. The present study used the cosine model to determine the circadian patterns of amino acids, d opamine, and prolactin concentrations, which were analyzed over a 24-h our period in serum of healthy subjects, drug-free schizophrenic patie nts, and neuroleptic-treated schizophrenic patients. The mesor (the da ily mean) of phenylalanine was lower in drug-free schizophrenic women than in healthy women. The mesors of the ratio of phenylalanine or tyr osine to competing amino acids were similar in healthy subjects and pa tients. The ratio of phenylalanine/competing amino acids showed a phas e advance (i.e., earlier onset of the time of highest concentration) i n drug-free patients compared with healthy subjects. Schizophrenic pat ients displayed a higher dopamine mesor than healthy subjects. Female drug-free schizophrenic patients had lower prolactin mesors and lower amplitudes (i.e., half of the total predictable change in rhythm) than healthy women. Compared with healthy subjects, schizophrenic patients showed a phase advance of circadian prolactin concentrations. Neurole ptics raised the prolactin mesor and amplitudes but did not elicit any phase change in amino acids, dopamine, or prolactin. These data confi rm the indirect pharmacologic evidence of increased dopaminergic activ ity in schizophrenic patients that relates to dopamine's precursors an d to the neuroendocrine regulation of prolactin.