FIG. 3.

Neuroblast emigration towards the ischemic striatum after MCAO stroke. The location of the middle cerebral artery occlusion lesion is shown in purple. Red arrows show direction of neuroblast emigration. Ischemic stroke lead to a robust inflammatory response in the infarct area, with accumulation of large numbers of reactive astrocytes (green cells) and activated microglia/macrophages (pink cells). Inflammatory cells release various chemokines and chemoattractants such as stromal-derived factor 1 alpha (SDF-1α) and monocyte chemoattractant factor 1 (MCP-1). Neuroblasts from the SVZ migrate up chemotactic gradients along blood vessels and astrocytic processes towards the injury. Relatively little is known about the changes in the SVZ neurogenic niche which may facilitate the exit of neuroblasts out of their normal migratory pathway into the striatum. (To see this illustration in color the reader is referred to the web version of this article at www.liebertonline.com/ars).