Immunohistochemical analysis of protein expression after middle cerebral artery occlusion in mice

The effect of transient focal cerebral ischemia on protein regulation was studied in mice using multiparametric immunohistochemistry. Injury was characterized by measurements of blood flow, regional protein synthesis and terminal transferase biotinylated-dUTP nick end labeling (TUNEL). The proteins studied were selected from a previously established list of differentially regulated proteins and included the GTPases dynamin, RhoB, CAS and Ran BP-1, the transcription factors Nurr1 and p-Stat 6, the protein kinase MAPK p49, the splicing factors SRPK1 and hPrp16, the cell cycle control proteins cyclin B1 and Nek2, the inflammatory proteins FKBP12 and Rag2, the cell adhesion protein paxillin and the folding protein TCP-1. Regulation patterns were diverse and comprised ipsi- and/or contralateral up- and down-regulation with or without topical association to impeding cell death. Some proteins (SRPK1, TCP-1 and Nurr1) also exhibited post-ischemic translocation from the nucleus to the cytosol. Our observations stress the importance of regional analysis for the interpretation of proteomic data, and contribute to the identification of new pathways that may be involved in the evolution of post-ischemic brain injury.