Subnormal CSF levels of neurotensin in a subgroup of schizophrenic patients: Normalization after neuroleptic treatment

Neurotensin has been shown to possess many pharmacological properties that are similar to those of neuroleptic drugs. The authors determined CSF levels of immunoreactive neurotensin in 12 normal healthy volunteers and in 21 schizophrenic patients during both drug-free and neuroleptic-treated phases. In contrast to the healthy volunteers, the schizophrenic patients showed a bimodal distribution of the peptide during the drug-free phase. A subgroup of 9 schizophrenic patients had markedly lower levels than the rest of the schizophrenic patients, whose levels were comparable to those of the healthy volunteers. During neuroleptic treatment, the CSF levels of the 9 schizophrenic patients with initially low values rose to normal concentration.