Transient middle cerebral artery occlusion model (tMCAO) in the mouse. (A,B) Three coronal sections through the brain in individual animals. (A) A cerebral infarct at 24 hours after 30 minutes of tMCAO and (B,C) after 1 hour of tMCAO as revealed on tissue sections stained for 2,3,4-triphenyltetarzoliumchloride (TTC), a mitochondrial marker. Red areas represent vital brain tissue; white areas indicate cerebral infarctions. With short occlusion times of 30 minutes, infarcts are restricted to the basal ganglia (arrow in A), whereas prolonged occlusion leads to infarction of the entire MCA territory (B). (D) Infarct development can also be assessed in vivo by magnetic resonance imaging (MRI). Infarcts appear white on T2-w or diffusion-weighed MRI (D) and correspond closely to the extent of infarction seen on tissue sections (C). TTC scans were taken from an Epson Perfection 3200 Photo flatbed scanner (Seiko Epson, Nagano, Japan) at 600 dpi and processed using Epson Scan software. MRI was performed on a 17.6-Tesla ultrahigh field MR unit (Biospin; Bruker BioSpin, Ettlingen, Germany) using a custom-made dual channel surface coil designed for the examination of mouse heads (A063HACG; Rapid Biomedical, Würzburg, Germany). The image protocol comprised a coronal diffusion–weighted sequence (slice thickness, 0.5 mm). MR images were transferred to an external workstation (Leonardo; Siemens, Berlin, Germany) for data processing.