64.04 Evidence for cellular and proteomic abnormalities in the insular cortex in schizophrenia Pennington K, Dicker P, Dunn M J, Cotter D R 1 and 4; Department <strong>of</strong> Psychiatry and 2; Molecular and Cellular Therapeutics, Royal College <strong>of</strong> Surgeons in Ireland. 1 & 3 Proteome Research Centre, UCD Conway Institute <strong>of</strong> Biomolecular and Biomedical Research, University College Dublin, Ireland. The insular cortex is a paralimbic area <strong>of</strong> the brain thought to have a role in sensory integration, auditory hallucinations and language. Structural and functional MRI studies have shown abnormalities in size and activity in schizophrenic patients in comparison with control cases. No study do date has investigated these abnormalities at the cellular or molecular level. In this study stereological examination <strong>of</strong> neuronal and glial size and density was evaluated in lamina II and III <strong>of</strong> the posterior region <strong>of</strong> the insular cortex in 15 schizophrenic, 15 bipolar, 15 major depressive and 15 control patients. Following statistical analysis using ANCOVA, lamina II neuronal volume was shown to be significantly decreased in schizophrenia. 2D difference gel electrophoresis (2D-DIGE) was subsequently used to analyze differences between protein expression in schizophrenia and control cases in laser-assisted microdissected lamina II tissue. Seventy eight protein spots were found to be significantly differentially expressed (p
64.08 Modulation <strong>of</strong> ketamine-induced blood-oxygen level dependent (BOLD) responses by an AMPA antagonist’ de Groote C, McKie S, Deakin B, Williams S <strong>Neuroscience</strong> and Psychiatry Unit, and Imaging Science and Biomedical Engineering; University <strong>of</strong> Manchester, Manchester, M13 9PT, United Kingdom The glutamate hypothesis <strong>of</strong> schizophrenia proposes an important role for glutamate in the symptoms <strong>of</strong> the disease, which can be mimicked experimentally by ketamine (KET). We previously established localised changes in blood-oxygenation level dependent (BOLD) contrast in the rat brain in regions relevant to schizophrenia using direct pharmacoMRI. To investigate whether KET-induced BOLD changes are due to glutamate release and subsequent stimulation <strong>of</strong> post-synaptic glutamate receptors, we pretreated with GYKI52466, an AMPA antagonist. Young adult male rats were anaesthetised with is<strong>of</strong>lurane (1.5%) and placed in a 7T horizontal magnet. BOLD sensitive T2*-weighted images were acquired using a gradient echo sequence. Ten minutes before the start <strong>of</strong> functional imaging, vehicle or GYKI52466 (10 mg/kg) was injected (i.p.). In total 72 volumes <strong>of</strong> 70 seconds were collected, with 18 volumes (20 minutes) <strong>of</strong> baseline scans and 52 post-injection scans (63 minutes). KET (30 mg/kg s.c.) was injected at the start <strong>of</strong> volume 19. Data were pre-processed and analyzed using a general linear model in SPM2. Drug and time interactions were investigated using a one way ANOVA (uncorrected, p<0.01). GYKI52466 pre-treatment reduced KET-induced activations in the thalamus, hippocampus, auditory cortex, cingulate cortex and retrosplenial cortex. GYKI52466 pre-treatment enhanced KET-induced BOLD changes in the striatum, somatosensory cortex, colliculus, and somatosensory cortex. Our study demonstrates that pre-treatment with the AMPA antagonist GYKI52466 reduces KET-induced BOLD changes in key areas <strong>of</strong> the rat brain. This supports recent findings for a role <strong>of</strong> enhanced glutamatergic transmission in schizophrenia. CdG was supported by a NARSAD YIA Award 65.01 Confocal microendoscopic analysis <strong>of</strong> neuromuscular phenotypes in ethylnitrosourea (ENU)-mutagenised WldS mice. Wong F, Fan L, Coleman M P, Blanco G, Ribchester R R MRC Mary Lyon Centre, Harwell and Centre for <strong>Neuroscience</strong> Research, 1 George Square, Edinburgh. Severing the motor nerve supply to skeletal muscle normally triggers rapid Wallerian degeneration. In homozygous WldSmutant mice, axon degeneration is actively delayed by expression <strong>of</strong> an Nmnat/Ube4b chimeric gene: disconnected motor nerve terminals persist for several days; and axons are preserved for up to three weeks, rather than 24-72 hours characteristic <strong>of</strong> wild-type mice. However, in heterozygous WldS mice axotomy-induced degeneration <strong>of</strong> presynaptic motor nerve terminals occurs at a normal rate. This observation supports a compartmental model <strong>of</strong> neurodegeneration, according to which cell bodies, axons and nerve terminals degenerate in response to surgical or chemical trauma by different sub-cellular mechanisms. Discovery <strong>of</strong> other gene mutations that selectively protect synapses would validate this hypothesis. We are attempting this in a high-throughput screen <strong>of</strong> mice mutagenised by ethylnitrosourea (ENU), designed to reveal covert neuromuscular phenotypes after axotomy in vivo. We perform a novel phenotypic assay: 650µm or 1500 µm tipped fibre-optic probes connected to a Cellvizio confocal microendoscope (Mauna Kea Technologies, Paris). The procedure is minimally invasive yet can resolve intact and degenerating axons and synapses in living anaesthetised (halothane/N20) transgenic mice that co-express yellow fluorescent protein (YFP) in motor neurones as a biomarker. We use WldS mice as a sensitized background, examining for either additive synaptic protection or block <strong>of</strong> axonal protection following axotomy in the F1 <strong>of</strong>fspring <strong>of</strong> the ENU x thy1.2:YFP16-WldS crossbred mice. To date, we have studied more than 23 ENU lines but none has yet shown evidence <strong>of</strong> interaction with the WldS/+ phenotype. 65.02 Strong protection <strong>of</strong> annulospiral Ia afferent axon terminals from Wallerian degeneration in muscle spindles <strong>of</strong> WldS mutant mice. Oyebode O R O, Singhota J, Gillingwater T H, Ribchester R R Centre for <strong>Neuroscience</strong> Research, University <strong>of</strong> Edinburgh, EH8 9JZ The Wld S mouse is a mutant in which axons survive several weeks after transection, by virtue <strong>of</strong> expression <strong>of</strong> a chimeric Nmnat1/Ube4b protein. The Wld S phenotype extends to axons in both CNS and PNS. Wld S also protects presynaptic terminals but studies on this have been limited to neuromuscular junctions and synapses in the brain. There are no published data on the degeneration <strong>of</strong> sensory axons and their terminals in these mice. Here we report that annulospiral endings <strong>of</strong> Ia afferent axons are very strongly preserved after axotomy in mice. Homozygous or heterozygous Wld S mice crossbred with thy1.2-CFP transgenic mice were sacrificed 1-20 days after sciatic nerve transection under halothane/N 2 O inhalation anaesthesia. Fluorescence microscopy <strong>of</strong> whole mount preparations <strong>of</strong> lumbrical muscles revealed excellent preservation <strong>of</strong> annulospiral endings on muscle spindles for at least 10 days after axotomy. No significant difference was detected in the protection with age or gene dose, in contrast to the protection <strong>of</strong> motor nerve terminals, which degenerated rapidly in heterozygous and >4-month old homozygous Wld S mice. However, Ia afferent axons were protected for longer than their annulospiral endings. Quantitative image analysis <strong>of</strong> reconstructions from confocal projections (z-series) also suggested that slow degeneration <strong>of</strong> annulospiral endings in Wld S mice occurs by intercalary loss <strong>of</strong> their intrafusal annuli, rather than either retraction or fragmentation, as shown by axotomised motor terminals. Thus, like motor terminals, sensory endings are less well protected by WldSthan their parent axons, but sensory endings are protected better and longer than motor nerve endings. 65.03 Neuroprotective properties <strong>of</strong> the non-peptidyl radical scavenger IACVITA in rats following tMCAO. Nurmi A, Puoliväli J, Pussinen R, Soleti A, Bagate K, Paolini M, Riccardino F, Grundy R I, Yrjänheikki J Cerebricon Ltd, Microkatu 1, FIN-70211 Kuopio, FINLAND, , Medestea Research & Production S.p.A., Via Cernaia 31, 10121 Torino, , Forenap Pharma, France., , University <strong>of</strong> Bologna,, Bologna,, Italy., , , Substantial evidence exists to suggest that reactive free radicals are generated during brain ischemia. Anti-oxidant neuroprotective agents have also been found to be effective in animal models <strong>of</strong> stroke. However, clinical trials have proved inconsistent. Here we investigated the effect <strong>of</strong> a novel radical scavenger, IACVITA, on cerebral infarct volume and sensorymotor performance in a rat transient Middle Cerebral Artery Occlusion model (tMCAO). Male Sprague-Dawley rats were subjected to 90 min tMCAO and treated with i.p. or i.v. injections <strong>of</strong> vehicle or IACVITA after the onset <strong>of</strong> tMCAO. Sensory-motor performance was evaluated daily by 7 and 28 point Neuroscore tests (NS). Cerebral infarct volume was evaluated at 72 h after tMCAO. Rats exhibited a significant decrease in 7 and 28 point NS during the 3-day monitoring period. Rats treated with IACVITA i.p. (1 or 6 h after the onset <strong>of</strong> tMCAO) or i.v. (1 h after the onset <strong>of</strong> tMCAO) showed significant improvement in 7 and 28 point NS after tMCAO during the 3-day follow-up period when compared to vehicle treated rats. Cerebral infarct volumes were significantly decreased compared to vehicle in rats receiving IACVITA i.p. 1 or 6 h or i.v. 1 h after the onset <strong>of</strong> tMCAO, which supported observations from the 7 and 28 point NS tests. These results demonstrate that IACVITA has unique neuroprotective properties with a wide therapeutic window in 90 min tMCAO model in rats, which is reflected in the improved sensory-motor performance and reduced infarct volumes. 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