Neuronal Necrosis After Middle Cerebral Artery Occlusion in Wistar Rats Progresses at Different Time Intervals in the Caudoputamen and the Cortex

摘要: Background and Purpose Most brain lesions that develop after an artery is occluded evolve from initial stage of “ischemic injury” (probably reversible) to infarct or area where most neurons become necrotic. There scant information on the time must elapse arterial occlusion for undergo irreversible injury. The objective these experiments was chart course topographic distribution neuronal necrosis follows a large cerebral artery. Methods One hundred fifty-one adult rats (including 15 controls) were used in this study. forty-seven had right middle variable periods ranging 30 minutes 7 days. After processing brains histology, meticulous structural evaluation each specimen, including quantitation necrotic neurons, followed by detailed statistical analysis counts. Results Few isolated sites showed morphological signs during 4 hours; first significant increase percentage (15%) observed within territory 6 hours ( P <.05); 12 (65%) <.0001). Pannecrosis involving glial cells, blood vessels at 72 96 hours. However, even pannecrosis involved only preoptic lateral putamen; few intact remained visible cortex, scattered could be identified beyond edges “area pallor,” which does not clearly demarcated until 5 days occlusion. Conclusions predictable progression development permanent occlusion. Irreversible changes appear caudoputamen then spread cortex. causes lesion are known; however, therapeutic interventions start 1 2 may alter histopathologic responses form It remains determined whether extent neurological deficit induced correlates with number neurons.