Ischemic penumbra in a model of reversible middle cerebral artery occlusion in the rat.

摘要: It has become increasingly clear that a stroke lesion usually consists of densely ischemic focus and perifocal areas with better upheld flow rates. At least in rats cats, some these (“penumbral”) subsequently recruited the infarction process. The mechanisms may involve an aberrant cellular calcium metabolism enhanced production free radicals. In general, though, metabolic perturbation penumbra requires characterization. objective this article was to define distribution rat model reversible middle cerebral artery (MCA) occlusion, so as allow delineation aberrations responsible for subsequent infarction. We modified intraluminal filament occlusion recently developed by Koizumi et al. (1986), described more detail Nagasawa Kogure (1989), adopting it use both spontaneously breathing artificially ventilated rats. Successful MCA (achieved about 9/10 rats) judged unilateral EEG depression rats, neurological deficits, such circling, ones. CBF ipsilateral hemisphere reduced nearly constant values after 20, 60, 120 min rates being 10% 15–20% control (contralateral side). When left place (permanent occlusion) 2,3,5-triphenyl tetrazolium chloride (TTC) staining histopathology 24 h showed massive infarct on occluded side, extending from caudoputamen overlaying cortex occipital striate cortex. Animals recirculated 60 allowed survive 7 days histopathology, (lateral part or whole nucleus) 5/6 animals selective neuronal necrosis one animal. neocortex either infarcts, necrosis, no damage. There overlap between neocortical which were infarcted those salvaged reperfusion. data recovery studies histopathological endpoint large parts (penumbral) lend themselves events leading