Figure 6. Small stroke model of barrel cortex ischemia in rodents.

A. Focal ischemic insult to the barrel cortex is induced by permanent occlusion of the distal branches of the right or left middle cerebral artery combined with transient ligations of bilateral common carotid arteries. The barrel cortex is identified by the optical imaging in responding to whisker stimulation. B. Ischemia-induced barrel cortex infarct formation and cell death. Middle cerebral artery branch ligations induced a focal ischemic infarct and cell death in the barrel cortex. Selective damage occurred to the right barrel cortex region shown as a negative (white) area in triphenyl tetrazolium staining (red) 24 hrs after ischemia. The pink area between the normal cortex and ischemic core represents the bordering penumbra area. C. In the immunohistochemical image, Glut-1 staining (red) shows vascular endothelial cells in the penumbra and normal brain tissues. NeuN (blue) indicates neurons. Ischemic core shows the autofluorescence associated with damaged tissue. D and E. Cytochrome oxidase staining revealed the barrel column structures in the context of a normal cortex (D) and undergone ischemic damage (E). The lowercase letters “a”–”e” in image D illustrate the characteristic pattern of barrel distribution in the cortex. Fourteen days after ischemia, most of the barrel column structures disappear except a few barrel-like clumps (arrowhead) preserved in the peripheral region of the barrel cortex (E).