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The superior temporal gyrus (STG) is comprised of primary and secondary (association) auditory cortices and is considered the primary substrate of auditory signal processing and speech. Recently it has been the subject of multiple studies in the pathophysiology of schizophrenia. Neuroimaging studies show an inverse correlation between the STG volume and the severity of hallucinations. Here, we investigated the STG membrane proteome from rhesus monkeys treated chronically with 1st and 2nd generation antipsychotics at different dose levels. By coupling iTRAQ® reagent labeling with tandem mass spectrometry, we demonstrate proteome changes that occur in monkey STG membrane after anti-psychotic drug treatment. To study the proteome signature and to determine the effects of antipsychotic administration, rhesus monkeys were administered atypical antipsychotic clozapine (2.6mg/kg, b.i.d.; n=10), typical antipsychotic haloperidol- low dose (0.07mg/kg, b.i.d.; n=10) and –high dose (2mg/kg, b.i.d.; n=4) for 180 days and compared with controls (n=10). STG membrane proteins were harvested and pooled from monkeys and digested with trypsin. After labeling with iTRAQ reagents sample was fractionated into 30 fraction by XIC using a 90 minute reverse phase LC gradient and spotted directly onto stainless steel MALDI plates. Samples were analyzed using an AB SCIEX TOF/TOF™ 5800 system. A survey scan was performed on every sample spot and up to 30 precursors from each spot were automatically selected for MS/MS analysis. Database searches were done using ProteinPilot software 3.0 with Paragon and Pro Group algorithms against the NCBI non-redundant database. Approximately 1600 distinct peptides and approximately 300 proteins were identified with confidence (1% global FDR). Given the multivariate nature of the collected data, Principal Components Analysis (PCA) was used to determine relationships between the variables. The current study documents the first proteomic signature as well as the effects of chronic antipsychotic administration on protein expression in the primate STG.