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Primary objective: To determine whether propofol has a neuroprotective effect on hypoxic brain injury. Research design: A hippocampal slice, in artificial cerebrospinal fluid (ASCF) with glucose and oxygen deprivation (OGD), was used as an in vitro model for brain hypoxia. Methods and procedures: The orthodromic population spike (OPS) and hypoxic injury potentia1 (HIP) were recorded in the CA1 region when Schaffer collateral was stimulated in the CA3 region of the hippocampal slices during hypoxia. The concentrations of amino acid neurotransmitters in perfusion solution of hippocampal slices were directly measured using high performance liquid chromatography (HPLC). Morphological changes of neurons, astrocytes and mitochondria in CA1 region were observed using histology and electron microscopy. Neuronal apoptosis was evaluated with TUNEL assay. Main outcome and results: Propofol treatment delayed the elimination of OPS and improved the recovery of OPS; decreased frequency of HIP, postponed the onset of HIP and increased the duration of HIP. Propofol treatment also decreased the release of amino acid neurotransmitters such as aspartate, glutamate and glycine induced by hypoxia, but elevated the release of γ-aminobutyric acid (GABA). Morphological studies showed that propofol treatment attenuated oedema of pyramid neurons in the CA1 region and reduced apoptosis. Conclusions: Propofol has a neuro-protective effect on hippocampal neuron injury induced by hypoxia. [ABSTRACT FROM AUTHOR]

Background/Aims: It has been demonstrated that mitochondrial dysfunction is associated with Alzheimer's disease (AD); meanwhile, hypoxia-up-regulated mitochondrial movement regulator (HUMMR) plays an important role in regulating mitochondrial function. The present study aimed to confirm the association between HUMMR and mitochondrial function in AD. Methods: We detected the expression of HUMMR at transcriptional and translational levels in APP/PS1 double transgenic mice using real-time quantitative RT-PCR and Western blotting. Age- and gender-matched wild-type (WT) littermates were used as controls. Mitochondrial morphology was observed in the hippocampus and cortex of APP/PS1 double transgenic mice using transmission electron microscopy. Results: Damage to mitochondrial morphology in the hippocampus and cortex of APP/PS1 double transgenic mice was found, including swelling and cavitations. Our analysis showed no statistical differences in the expression of HUMMR between APP/PS1 double transgenic mice and WT littermates (p > 0.05). These results showed that there was no association between HUMMR and mitochondrial dysfunction in APP/PS1 transgenic mice. Conclusion: These results indicate that HUMMR does not play a key role in mitochondrial dysfunction in the APP/PS1 double transgenic AD mouse. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Primary objective: This study was designed to evaluate the effect of hypobaric hypoxia (HH) on the function and expression of P2X receptors in rat hippocampus CA1 pyramidal cells. Research design: The functional changes of P2X receptors were investigated through the cell HH model and the expressional alterations of P2X receptors were observed through the animal HH model. Methods and procedure: P2X receptors mediated currents were recorded from the freshly dissociated CA1 pyramidal cells of 7--day--old SD rats by whole cell patch clamp recording. The expression and distribution of P2X receptors were observed through immunohistochemistry and western blot at HH 3--day and 7--day. Main outcomes and results: In acute HH conditions, the amplitudes of ATP evoked peak currents were decreased compared to control. The immunohistochemistry and western blot results reflected there was no change in P2X receptors expression after 3 days HH injury, while P2X receptors expression was up--regulated in response to 7 days HH injury. Conclusions: These findings supported the possibility that the function of P2X receptors was sensitive to HH damage and long--term function decrease should result in the expression increase of P2X receptors. [ABSTRACT FROM AUTHOR]

Abstract: The current study obtained multi-modal MRI data from 28 immigrant high altitude (HA) young adults who were born and grew up at Qinghai-Tibetan plateau matched with 28 matched sea level (SL) controls. We compared their regional gray matter volumes (VBM) and white matter quality (DAI FA values) as well as resting state brain activity (Regional Homogeneity (ReHo) of BOLD-fMRI). We found that HA residents showed decreased gray matter volume at bilateral anterior insula, bilateral prefrontal cortex, the left precentral, the left cingulate and the right lingual cortex; accompanied by changed FA and ReHo values in relevant and other regions. The resting state activity at the hippocampus and the right insula were increasing with SL relocation. The HA subjects performed worse on a series of working memory tasks, with the ReHo values of several regions as significant predictors of their performance. This study demonstrated the cerebral and functional modifications with chronic high altitude hypoxia. [ABSTRACT FROM AUTHOR]