The biological processes underlying stroke are complex, and patients have a narrow repertoire of therapeutic opportunities. After the National Institutes of Health (NIH) convened the Stroke Progress Review Group in 2001, stroke research shifted from having a purely neurocentric focus to adopting a more integrated view wherein dynamic interactions between all cell types contribute to function and dysfunction in the brain. This so-called “neurovascular unit” provides a conceptual framework that emphasizes cell–cell interactions between neuronal, glial, and vascular elements. Under normal conditions, signaling within the neurovascular unit helps maintain homeostasis. After stroke, cell–cell signaling is disturbed, leading to pathophysiology. More recently, emerging data now suggest that these cell–cell signaling mechanisms may also mediate parallel processes of neurovascular remodeling during stroke recovery. Because plasticity is a signature feature of the young and developing brain, these concepts may have special relevance to how the pediatric brain responds after stroke.
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