BACKGROUND AND PURPOSE Arterial hypoxia mediates cerebral arteriolar dilation primarily via mechanisms involving activation of ATP-sensitive K+ channels (K[ATP]), which we have shown to be sensitive to ischemic stress. In this study, we determined whether ischemia/reperfusion alters cerebral arteriolar responses to arterial hypoxia in anesthetized piglets. Since adenosine plays an important rol...

Failure of glutamate uptake during ischemia can lead to neurotoxic accumulations of glutamate in brain extracellular space. Hypoxia and acidosis are metabolic consequences of ischemia that may individually or in combination impair glutamate uptake. We used primary rat astrocyte cultures to study the effects of acidosis, chemical hypoxia, and the combination of acidosis plus chemical hypoxia on ...

Myocardial ischemia/reperfusion (I/R) injury could lead to severe cardiovascular ischemic disease, including myocardial infarction and contractile dysfunction. Remifentanil demonstrated protective effect on I/R injury. The underlying pathophysiological mechanism was then investigated in this study. In the current study, primary cardiomyocytes were isolated from rats, preconditioned with remifen...

An effective treatment for brain ischemia is a pressing medical need. Research on brain ischemia has largely focused on understanding the mechanisms of neuron death as a way of identifying targets for therapy. An attractive alternative approach is to identify the survival strategies of hypoxia-tolerant neurons. The adaptation of vertebrate neurons to hypoxia occurs in at least three major ways:...

BACKGROUND Preconditioning phenomena provide evidence for adaptive responses to ischemia that have important implications for treatment/prevention of myocardial infarction. Hypoxia-inducible factor 1 (HIF-1) mediates adaptive transcriptional responses to hypoxia/ischemia. METHODS AND RESULTS Exposure of wild-type mice to intermittent hypoxia resulted in protection of isolated hearts against i...

Perinatal insults and subsequent neuroinflammation are the major mechanisms of neonatal brain injury, but there have been only scarce reports on the associations between hypoxic preconditioning and glial activation. Here we use neonatal hypoxia-ischemia brain injury model in 7-day-old rats and in vitro hypoxia model with primary mixed glial culture and the BV-2 microglial cell line to assess th...

An excessive intracellular accumulation of calcium (Ca2+) in neurons and glia has been proposed to represent a major 'final common pathway' for cell death arising from hypoxia-ischemia. To clarify the role of altered calcium flux into the perinatal brain undergoing hypoxic-ischemic damage, 7-day postnatal rats underwent unilateral common carotid artery ligation followed by systemic hypoxia with...

Acute renal failure resulting from hypoperfusion and hypoxia is a significant clinical problem. Hypoxia activates the heterodimeric transcription factor hypoxia inducible factor (HIF), leading to changes in gene expression that promote tissue adaptation and survival. To determine whether HIF may protect the kidney from ischemia-reperfusion injury, we subjected hif1a(+/-) and hif2a(+/-) mice to ...