[Biogenic amines and schizophrenia].
Three main biogenic amine hypotheses for the origin of schizophrenia are discussed. The dopamine theory of schizophrenia postulates a pathogenetic connection between the disease and changes in the activity of dopaminergic cells in the brain. The theory is mainly based on findings on the mechanism of action of neuroleptics, on the clinical features and pharmacology of the amphetamine psychosis, and on some amphetamine effects in animals. Several results are in good agreement with the assumption of a state of hyperactivity of central dopamine neurons, whereas others, e.g. the lack of an increased dopamine turnover, are not. According to another theory, schizophrenia is caused by reversible damage to central norepinephrine cells. So far the only empirical basis for this theory is the finding that the activity of dopamine-beta-hydroxylase, a marker enzyme for noradrenaline cells, is lowered in the brains of schizophrenic patients. Thus further confirmation is required. The transmethylation hypotheses assume that hallucinogenic amine metabolites are produced in the body and lead to the appearance of schizophrenic symptoms. Whether or not the occurrence of DMPEA, presumably an oxymethylation product of the dopamine metabolism, is specific for schizophrenics is still open to question; if it is, the meaning of this finding is obscure. Current results leave open the possibility that N-dimethyltryptamine or other N-methylated hallucinogenic biogenic amine metabolites cause the disease; however, this hypothesis is hardly confirmed by positive empirical results.
D000662:Amphetamines / Q000009:adverse effects; D001480:Basal Ganglia Diseases / Q000139:chemically induced; D003024:Clozapine / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism; D006801:Humans; D004130:N,N-Dimethyltryptamine / Q000378:metabolism; D010302:Parkinson Disease, Secondary / Q000139:chemically induced; D011941:Receptors, Adrenergic; D012559:Schizophrenia / Q000209:etiology*; D014149:Tranquilizing Agents / Q000494:pharmacology
D000662:Amphetamines; D011941:Receptors, Adrenergic; D014149:Tranquilizing Agents; D004299:Dopamine beta-Hydroxylase; D003024:Clozapine; D004298:Dopamine; D004130:N,N-Dimethyltryptamine
Biogene Amine und Schizophrenie