Within the brain we posit that small networks of highly interconnected neurons and glia, for example cortical columns, are semi-autonomous units oscillating between sleep-like and EPZ015666 cell line wake-like states. We review evidence showing that cells, small networks and regional areas of the brain share sleep-like properties with whole-animal sleep. A testable hypothesis focused on how sleep is initiated
within local networks is presented. We posit that the release of cell activity-dependent molecules, such as ATP and nitric oxide, into the extracellular space initiates state changes within the local networks where they are produced. We review mechanisms of ATP induction of sleep-regulatory substances and their actions on receptor trafficking. Finally, we provide an example of how such local metabolic
and state changes provide mechanistic explanations for clinical conditions, such as insomnia. “
“Endothelial nitric oxide synthase (eNOS) is a dynamic enzyme tightly controlled by co- and post-translational lipid modifications, phosphorylation and regulated by protein–protein interactions. In this study we have pharmacologically modulated the activation of eNOS, at different post-translational levels, to assess the role of eNOS-derived NO and regulatory mechanisms in tissue damage associated with spinal cord injury (SCI). SC trauma was induced by the application of vascular clips (force of 24 g) to the dura via a four-level T5–T8 laminectomy. SCI in mice resulted in severe trauma characterized by oedema, neutrophil infiltration, and production of inflammatory mediators, tissue damage and apoptosis. LY294002, an inhibitor CX-5461 datasheet of phosphatidylinositol
3-kinase that initiates Akt-catalysed phosphorylation of eNOS on Ser1179, was administered 1 h before the induction of SCI; 24 h after SCI sections were taken for histological examination and for biochemical studies. In this study we clearly demonstrated that pre-treatment with LY294002 reversed the increased activation of eNOS and Akt observed following SCI, and developed a severe trauma characterized by oedema, tissue Florfenicol damage and apoptosis (measured by TUNEL staining, Bax, Bcl-2 and Fas-L expression). Histological damage also correlated with neutrophil infiltration, assessed as myeloperoxidase activity. Overall these results suggest that activation of the Akt pathway in SC tissue subject to SCI is a protective event, triggered in order to protect the injured tissue through a fine tuning of the endothelial NO pathway. “
“Although synaptic plasticity in the human cerebral cortex is governed by metaplasticity, whether a similar mechanism operates at brainstem level is unknown. In this study in healthy humans we examined the effects and interactions induced by pairing supraorbital nerve high-frequency electrical stimulation (HFS) protocols on the R2 component of the trigeminal blink reflex [Mao, J.B. & Evinger, C (2001) J Neurosci., 21:RC151(1–4)].