[Experimental studies on pharmacologic protection of the brain against focal ischemia. 1. Focal brain ischemia model in rats].
Occlusion of the middle cerebral artery (MCA) in rats is being used increasingly widely as an experimental model of focal brain ischemia. However, the incidence of infarction or the size of infarction is variable. As a preliminary study we examined the anatomical variations of branching of the middle cerebral artery (MCA) and the incidence and extent of infarction and the time course of neurologic deficits following occlusion of the MCA at various sites in Sprague-Dawley (SD) rats and spontaneously hypertensive rats (SHR). Variations of branching of the MCA were closely observed in 91 rats (49 SD rats and 42 SHR). In two-thirds, the olfactory branch was single and arose from the MCA proximal to the medial border of the olfactory tract. In a small number of rats, the olfactory branch was single, but it arose at or near the lateral border of the olfactory tract, or two olfactory branches arose at both medial and lateral borders of the olfactory tract. The lateral or the tandem occlusion group caused infarction of the pallium in only one of 7 rats. Neurologic deficit was also minimal and transient and the size of infarction was small in the lateral occlusion group. In the tandem occlusion group, neurologic deficit was more severe, but it was still transient. The branch occlusion group and the ICV group caused large infarction of the pallium with moderate neurologic deficits in 5 of 8, and 6 of 8 rats, respectively. The medial occlusion group caused infarction in the pallium and/or basal ganglia in 5 of 6 rats, and neurologic deficits were severe and persistent.(ABSTRACT TRUNCATED AT 250 WORDS)
Shiino
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D000818:Animals; D002545:Brain Ischemia / Q000473:pathology* / Q000503:physiopathology; D002536:Cerebral Arteries / Q000033:anatomy & histology / Q000473:pathology; D004195:Disease Models, Animal; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains