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01-Mar-2001
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Arch Hellen Med, 17(5), September-October 2000, 491-505
REVIEW
Inflammatory response after acute stroke
K. HADJIGOGOS
1st Department of Internal Medicine, “G. Gennimatas”
General Hospital, Thessaloniki, Greece
Increasingly, data from animal models of cerebral ischemia and preliminary human
studies show that inflammatory mechanisms play an important role in secondary
neuronal injury after acute cerebral ischemia. Ischemia followed by reperfusion
rapidly leads to the expression of inflammatory cytokines, especially TNF-α
and IL-1β, which stimulate a cascade of events involving local endothelial cells,
neurons, astrocytes, and perivascular cells. This initial release of cytokines
is followed by a secondary release of cytokines such as IL-6 and IL-8, an increase
in components of the coagulation system, and an up-regulation of cell adhesion
molecules. This results in an overabundant recruitment of leucocytes which can
decrease perfusion by blocking vessels directly, releasing vasoconstricting
substances and killing endothelial cells. Leucocytes cross into the brain, where
they degranulate, release cytotoxic enzymes such as myeloperoxidase, and generate
oxygen-derived free radicals. Monoclonal antibodies against leucocyte adhesion
molecules have been shown to reduce infarct volume in animal models of ischemia-reperfusion,
but there are a number of constraints to the application of this therapeutic
approach in human acute cerebral ischemia. It is widely expected that increased
understanding of the inflammatory and immunologic mechanisms relevant to acute
cerebral ischemia will offer more rational and hopeful treatment for acute stroke.
Key words: Αdhesion molecules, Brain ischemia/reperfusion, Cytokines, Inflammation.