Neuro-metabolite profiles of rodent models of psychiatric dysfunctions characterised by MR spectroscopy.

Neuroimaging endophenotypes in animal models provide an objective and translationally-relevant alternative to cognitive/behavioral traits in human psychopathologies. Metabolic alterations, such as those involved in the glutamate-cycle, have been proposed to play a preponderant role in both depression and schizophrenia. Chronic Mild Unpredictable Stress (CMUS) and sub-chronic administration of NMDA receptor antagonist generate animal models of depression and schizophrenia, respectively.

Intracerebral injection of preformed synthetic tau fibrils initiates widespread tauopathy and neuronal loss in the brains of tau transgenic mice.

Neurofibrillary tangles composed of hyperphosphorylated fibrillized tau are found in numerous tauopathies including Alzheimer's disease. Increasing evidence suggests that tau pathology can be transmitted from cell-to-cell; however the mechanisms involved in the initiation of tau fibrillization and spreading of disease linked to progression of tau pathology are poorly understood. We show here that intracerebral injections of preformed synthetic tau fibrils into the hippocampus or frontal cortex of young tau transgenic mice expressing mutant human P301L tau induces tau hyperphosphorylation and aggregation around the site of injection, as well as a time-dependent propagation of tau pathology to interconnected brain areas distant from the injection site.

Attentional performance of (C57BL/6Jx129Sv)F2 mice in the five-choice serial reaction time task.

Impaired attention is evident in several neurological and psychiatric disorders. In the present study, attentional capabilities were measured in the operant five-choice serial reaction time task (5-CSRTT) in male (C57BL/6Jx129Sv)F2 hybrid (B6129F2) mice. Main aims were to validate and standardize the test in these mice: to setup procedures, measure potential beneficial effects of sub-chronic nicotine in degraded versions of the 5-CSRTT (by decreasing stimulus duration, inducing white noise and making the stimuli unpredictable) and study disruptive effects of additional administration of the muscarinic antagonist scopolamine.

Lubeluzole protects sensorimotor function and reduces infarct size in a photochemical stroke model in rats.

Posttreatment with lubeluzole, the S-isomer of a novel 3,4-difluoro benzothiazole, potently rescued tactile/proprioceptive hindlimb placing reactions contralateral to unilateral thrombotic infarcts in the hindlimb area of the parietal sensorimotor neocortex of rats. Administered at 5 min postinfarct, a single i.v.

Neocortical localization of tactile/proprioceptive limb placing reactions in the rat.

The present study was aimed at delineating the neocortical substrate of tactile/proprioceptive limb placing reactions in rats by means of behavioral tests that excluded the participation of facial stimuli in limb function. Using a photochemical technique, we made unilateral focal lesions in the frontal and parietal neocortex. Fore- and/or hindlimb placing deficits resulted from damage to a fronto-parietal region lying between the medial agranular cortex and the primary somatosensory (whisker barrel field) cortex.

Ionic channels, cholinergic mechanisms, and recovery of sensorimotor function after neocortical infarcts in rats.

Unilateral photochemical infarcts were produced in the hind limb sensorimotor neocortex of 243 rats by intravenous injection of the fluorescein derivative Rose Bengal and focal illumination of the intact skull surface. Facial contact stimuli governed the degree and recovery rate of contralateral tactile/proprioceptive forelimb placing reactions. Contralateral forelimb placing recovered, whereas hind limb placing was resistant to recovery.