Neurotransmitters, receptors and neuropeptides in post‐mortem brains of chronic schizophrenic patients

Abstract

In the analysis of post-mortem brains of 14 chronic schizophrenic patients and 10 controls, biochemical evidence of a hyperdopaminergic state was found in the basal ganglia of schizophrenics; tyrosine hydroxylase activity was increased with a concomitant increase of homovanillic acid. Unusually high tyrosine hydroxylase activity was noted in 2 schizophrenic cases. The B_max value of ³H-spiperone binding for schizophrenics was higher than the controls. We also found increased specific binding of ³H-kainic acid to the prefrontal cortex in schizophrenics. A negative correlation existed between ³H-kainic acid binding in the medial frontal cortex, and glutamic acid content in various brain areas. Increased immunoreactivity of substance P was found in more than ten brain areas. Methionineenkephalin was also increased in three areas of the prefrontal cortex of schizophrenics. These results suggest that the hyperdopaminergic state co-existed with glutamatergic hypofunction and increased neuropeptides in various brain areas of chronic schizophrenic patients.