title: Characterization of olfactory bulb glomeruli in schizophrenia.
abstract: Olfactory deficits, observed in schizophrenia, may be associated with a disruption of synaptic transmission in the olfactory system. Using immunohistochemistry and optical densitometry, we assessed the integrity of the synaptic connection between olfactory receptor neurons and olfactory bulb target neurons in schizophrenia by comparing the level of eight proteins, expressed in the olfactory bulb glomeruli, among schizophrenia and control subjects. In schizophrenia, no change was observed in the levels of OMP, GAP43 and NCAM, proteins expressed by olfactory receptor neurons, suggesting an intact innervation of the olfactory bulb by these neurons. This was supported by the absence of change in calbindin level, which has been shown to decrease after the destruction of the olfactory epithelium. The level of synaptophysin, a pre-synaptic protein, was also unchanged. These findings suggested that axons of olfactory receptor neurons establish synapses with their olfactory bulb targets in schizophrenia. The absence of change in the level of poorly phosphorylated neurofilament of moderate and high molecular weight (NFM/HP) suggested no lack of dendritic innervation despite a previously seen reduction of glomerular MAP2 level in schizophrenia subjects. This and above findings were consistent with the absence of change in the level of beta-tubulin III, a protein expressed by neurons of both olfactory epithelium and bulb. Finally, we noted no significant decrease in trkB level, a neurotrophin receptor involved in the olfactory epithelium maintenance. This study showed no evidence of major structural alteration of the synapse between the olfactory epithelium and bulb in schizophrenia.
authors.affiliation: Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. Lise.Rioux@drexel.edu
authors.forename: Lise
authors.initials: L
authors.lastname: Rioux
authors.forename: Edward Isaac
authors.initials: EI
authors.lastname: Gelber
authors.forename: Leila
authors.initials: L
authors.lastname: Parand
authors.forename: Hala Altaf
authors.initials: HA
authors.lastname: Kazi
authors.forename: Joannie
authors.initials: J
authors.lastname: Yeh
authors.forename: Rebecca
authors.initials: R
authors.lastname: Wintering
authors.forename: Warren
authors.initials: W
authors.lastname: Bilker
authors.forename: Steven Edward
authors.initials: SE
authors.lastname: Arnold
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001369:Axons / Q000378:metabolism; D015415:Biomarkers; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D009473:Neuronal Plasticity; D009830:Olfactory Bulb / Q000378:metabolism / Q000473:pathology*; D009831:Olfactory Mucosa / Q000294:innervation* / Q000378:metabolism; D018034:Olfactory Receptor Neurons / Q000378:metabolism / Q000473:pathology*; D011446:Prospective Studies; D012559:Schizophrenia / Q000378:metabolism / Q000473:pathology*; D018709:Statistics, Nonparametric; D009435:Synaptic Transmission
chemical_list: D015415:Biomarkers; D009419:Nerve Tissue Proteins