HUMAN OLFACTORY MUCOSA IN SCHIZOPHRENIA

Recent evidence indicates that developmental anomalies may underlie so me symptoms of schizophrenia, while psychophysical studies have demons trated olfactory deficits in this disease. The postmortem olfactory mu cosa of elderly schizophrenic patients was examined to characterize th e molecular phenotype of this tissue. The distribution of developmenta lly regulated cytoskeletal proteins, a synaptic vesicle protein, a neu ral marker protein, a receptor for trophic molecules, axonal guidance and cell migration proteins, and neuronal and glial cytoskeletal prote ins of various degrees of phosphorylation was examined by immunohistoc hemistry. Both schizophrenic and control subjects exhibited dystrophic neurites that were immunoreactive for synaptophysin, microtubule-asso ciated proteins (MAP1B), and neurofilament proteins. No major histoche mical or morphologic differences in either the expression or distribut ion of these proteins were observed in the olfactory epithelium of sch izophrenic compared to control subjects. These studies indicated that dystrophic neurites frequently occurred in the olfactory mucosa of bot h schizophrenics and neurologically normal adults. The absence of majo r immunocytochemical abnormalities suggested that olfactory deficits i n schizophrenia may be due to more subtle cellular or molecular differ ences or to abnormalities in olfactory regions of the central nervous system rather than in the olfactory epithelium.