Transient focal cerebral ischemia was induced in MRP1 deficient (n=20) or FVB mice (n=15) by MCAO. A, MRP1 KO mice presented larger stroke-induced lesion compared to FVB mice after 48h reperfusion (FVB, n=8; MRP1 KO, n=12). B, Protein expression of MRP1 was increased in infarct hemisphere of FVB mice (n=3). C, MRP1 deficient mice contained significantly higher level of GSSG in stroke-affected hemisphere compared to that of FVB mice (n=4). *P<0.05 compared with corresponding contralateral hemisphere; †P<0.05 compared with FVB; §P<0.05 compared with infarct hemisphere of FVB.