Alteration in serum neural cell adhesion molecule in patients of schizophrenia.

INTRODUCTION: The neural cell adhesion molecule (N-CAM) plays important roles in neural migration, synaptogenesis and CNS development. Change of N-CAM fragments in CSF of schizophrenic patients was reported previously, and we aimed to detect difference in circulating N-CAM in the serum of schizophrenic patients and healthy controls. METHODS: Samples were from 14 chronic schizophrenic patients including 3 drug naïve patients and 11 healthy controls. After removal of albumin and globulin, N-CAM fragments were measured by Western blot technique with monoclonal antibody. RESULTS: N-CAM immunoreactive bands were detected primarily at 180, 140, 120, 75, 68 and 52 kDa. Samples from patients and controls showed similar patterns of bands, but schizophrenic patients showed increases or decreases at some bands intensity compared to healthy controls. The 68 kDa/73-75 kDa bands intensity ratio was substantially elevated in schizophrenic patients (0.262+/-0.14 in patients, 0.065+/-0.04 in controls) especially, the three drug naïve patients had a higher value of this ratio compared to the medicated patients. One drug naïve patient showed a decrease in this ratio after one month of antipsychotic medication. CONCLUSIONS: The results suggest elevated membrane turnover and/or abnormalities in the regulation of proteolysis of N-CAM in schizophrenia.