BACKGROUND AND PURPOSE Brain edema is a life-threatening consequence of stroke and leads to an extension of the affected tissue. The space-occupying effect due to brain edema can be quantified in rat stroke models with the use of MRI. The present study was performed to test 2 hypotheses: (1) Can quantification of the space-occupying effect due to brain edema serve as a noninvasive measure for b...

BACKGROUND AND PURPOSE Aquaporin-4(AQP4) is an abundant water channel protein in brain that regulates water transport to maintain homeostasis. Cerebral edema resulting from AQP4 over expression is considered to be one of the major determinants for progressive neuronal insult during cerebral ischemia. Although, both upregulation and downregulation of AQP4 expression is associated with brain path...

Exercise training is a neuroprotective strategy in cerebral ischemic injury, but the underlying mechanisms are not yet clear. In the present study, we investigated the effects of treadmill exercise pretreatment on the expression of mitochondrial dynamic proteins. We examined the expression of OPA1/DLP1/MFF/Mfn1/Mfn2, which regulates mitochondrial fusion and fission, and cytochrome C oxidase sub...

Aquaporin-4 (AQP4) is a family member of water-channel proteins and is dominantly expressed in the foot process of glial cells surrounding capillaries. The predominant expression at the boundaries between cerebral parenchyma and major fluid compartments suggests the function of aquaporin-4 in water transfer into and out of the brain parenchyma. Accumulating evidences have suggested that the dys...

The objective of the present study was to examine the relationship among extravascular pulmonary water, intracranial and cerebral perfusion pressure, hemodynamic parameters (eg, cardiac index, system vascular resistance index), and brain stem function during acute ischemic stroke. The subjects were 17 comatose patients with ischemic stroke who were admitted to an intensive care unit. The result...

BACKGROUND Experimental studies have shown that ischemic postconditioning can reduce neuronal injury in the setting of cerebral ischemia, but the mechanisms are not yet clearly elucidated. This study was conducted to determine whether ischemic postconditioning can alter expression of heat shock protein 70 and reduce acute phase neuronal injury in rats subjected to transient focal cerebral ische...

The effect of niravoline (RU 51599), a kappa opioid receptor agonist with water diuretic properties, was assessed on the resorption of postischemic cerebral edema in the conscious mouse in comparison with U 50488, another kappa opioid receptor agonist, and mannitol. Ischemia was obtained by permanent occlusion of the right middle cerebral artery. Twenty-four hours after occlusion, at a time whe...

We measured brain tissue Po2 in the frontal and occipital cortices, mid-brain and basal ganglia in monkeys for up to 5 hours after 16 min global brain ischemia to gain some insight into those factors responsible for the selective vulnerability of the brain to ischemic anoxia. Brain tissue Po2 measurements were made with gold microelectrodes with tip diameters of 5 to 10 nm. Reoxygenation of the...

BACKGROUND AND PURPOSE Glial cell line-derived neurotrophic factor (GDNF) plays important roles in the survival and recovery of some mature neurons under pathological conditions. However, the effect of GDNF in ameliorating ischemic brain injury has not been well documented. Therefore, we investigated a possible effect of GDNF on the changes of infarct size, brain edema, DNA fragmentation, and i...

Both oxygen free radicals and excitatory amino acids have been implicated as important cellular toxins in ischemic brain. Recent in vitro studies suggest that there may be a mutual interaction between these two mediators. We explored the relation between oxygen free radicals and excitatory amino acids in the development of ischemic brain edema in vivo. Male Sprague-Dawley rats were treated with...