Increased levels of SNAP-25 and synaptophysin in the dorsolateral prefrontal cortex in bipolar I disorder.
OBJECTIVE
In order to identify whether the mechanisms associated with neurotransmitter release are involved in the pathologies of bipolar disorder and schizophrenia, levels of presynaptic [synaptosomal-associated protein-25 (SNAP-25), syntaxin, synaptophysin, vesicle-associated membrane protein, dynamin I] and structural (neuronal cell adhesion molecule and alpha-synuclein) neuronal markers were measured in Brodmann's area 9 obtained postmortem from eight subjects with bipolar I disorder (BPDI), 20 with schizophrenia and 20 controls.


METHODS
Determinations of protein levels were carried out using Western blot techniques with specific antibodies. Levels of mRNA were measured using real-time polymerase chain reaction.


RESULTS
In BPDI, levels of SNAP-25 (p < 0.01) and synaptophysin (p < 0.05) increased. There were no changes in schizophrenia or any other changes in BPDI. Levels of mRNA for SNAP-25 were decreased in BPDI (p < 0.05).


CONCLUSIONS
Changes in SNAP-25 and synaptophysin in BPDI suggest that changes in specific neuronal functions could be linked to the pathology of the disorder.
Rebecca L. Cooper Research Laboratories, The Mental Health Research Institute of Victoria, Parkville, Victoria, Australia. elscarr@unimelb.edu.au
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Scarr
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Gray
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Keriakous
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Robinson
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Dean
D000906:Antibodies; D001714:Bipolar Disorder / Q000276:immunology / Q000378:metabolism*; D015815:Cell Adhesion Molecules / Q000276:immunology / Q000378:metabolism; D018929:Cell Culture Techniques; D034284:Dynamin I / Q000276:immunology / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000378:metabolism* / Q000473:pathology; D050765:Qa-SNARE Proteins / Q000276:immunology / Q000378:metabolism; D050683:R-SNARE Proteins / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000276:immunology / Q000378:metabolism; D012559:Schizophrenia / Q000276:immunology / Q000378:metabolism; D016708:Synaptophysin / Q000378:metabolism*; D050825:Synaptosomal-Associated Protein 25 / Q000378:metabolism*; D051844:alpha-Synuclein / Q000276:immunology / Q000378:metabolism
D000906:Antibodies; D015815:Cell Adhesion Molecules; C491152:NRCAM protein, human; D050765:Qa-SNARE Proteins; D050683:R-SNARE Proteins; D012333:RNA, Messenger; C494208:SNAP25 protein, human; D016708:Synaptophysin; D050825:Synaptosomal-Associated Protein 25; D051844:alpha-Synuclein; D034284:Dynamin I