Brain imaging of schizophrenia : The dopamine hypothesis

The dopamine hypothesis of schizoprenia was formulated thirty years ago and postulates that the symptoms of schizophrenia are related to an increased centraldopaminergic neurotransmission.The two fundamental assumptions that underly the dopaminie hypothesis of schizzophrenia have reccived support from brain imagingstudies on the dopamine system. There is as high occupancy of central D2-dopamine receptors in patients that are treated with clinically effective doses of classical antipsychotic drugs and recent studies indicate an abnormal function of the presynaptic dopaminergic neuron. Early reports of elevated postsynaptic D2-dopamine receptors in schizophrenic brains ppost-mortem have,however, not been consistenly confirmed by brain imaging studies of young neuroleptic-naive patients with schizophrenia. Suitable methods are now developed for brain imaging of the dopamine systemm in the limbic and neocortical regions that are of central enterst in schizophrenia research