Histological location of core and penumbra of cortex and striatum underwent focal cerebral is-chemia and reperf usion

Objective To observe the pathological changes of cerebral ischemia and locate the histologicl positions of microdialytic probe i n core and penumbra of cortex and striatum.Methods The rat model of local cere bral ischemia by occluding middle cerebral artery was used.The rats underwent 1or2h of ischemia and then reperfusion for23h or22h,rspectively.The is c hemic damage was observed by HE staining and analyzed quanititatively by image a nalysis.Results The cores in the groups of1h or2h ischemia were dis tributed in the areas supplied by middle cerebral artery and the penumbra was lo cated on the surround ing areas of cores.The core displayed tissure necrosis completely while the penum bra dis played selective neu ron death.The volumes of cores in cortex and striatum,and hemisphere dam age in the groups of2h ischemia were s ignificantly larger than that in the group of1h ischemia(P0.02?0.01 ?0.01and0.05,respectively),but the volumes of penumbras were no sta tistical difference.Accord ing to the stereotaxic atlas of the rat brain,we d etermined the locations of microdialytic probes in core and penum bra in cortex and striatum underwent 2h and1h ischemia.Conclusion The degree of is chemic d amdge is related to the duration of ischemia and penumbra is existed in cortex a nd striatum dur ing local cerebral ischemia.The positions of microdia lytic pro bes in core and penumbra of cortex or stria tum will provide the evidence to uti lize the cerebral microdialysis to explore the mechanisms of cerebral is chemi a,especialy the late brain damage.