(A, B) Animals subjected to 2-hour MCAo and 24 hours reperfusion showed marked increased expression of c-Fos, an immediate early gene associated with neuronal stress or injury. Animals pre-injected with mismatch RNA showed greater expression of c-Fos compared to animals pre-injected with PAR-1 shRNA. (C) Par-1 knockdown significantly reduced the total area of c-Fos expression in ischemic animals, measured with planimetry from stained sections, Mean ± SE (n=7). ***P<0.001, Students t-test for independent samples. (D, E) Cells counted in 20× magnification high power fields showed essentially no co-localization of PAR-1 shRNA positive GFP cells with c-Fos positive cells. Scale bars (A, B) 200μm (inset: 100μm); (E) 20μm.