Akademik Veri Yönetim Sistemi
Brain Research, cilt.822, sa.1-2, ss.260-264, 1999 (SCI-Expanded)
We examined blood flow changes and histology in the hippocampus induced by occlusion of the middle cerebral artery (MCA) by a filament in Swiss albino and SV-129 mice (n = 67) and in Wistar rats (n = 64). Filling cerebral arteries with carbon black revealed that one or both posterior communicating arteries were hypoplastic in 50% of Swiss mice. Ischemic changes were detected in the ipsilateral hippocampus with 2,3,5-triphenyl tetrazolium chloride or hematoxylin and eosin staining when these mice were subjected to 2-h MCA occlusion and 22-h reperfusion. No such abnormalities were found in SV-129 mice and Wistar rats (except one). The hippocampal blood flow dropped to 60 ± 2.3% of the baseline in mice with a normal circle of Willis but to 37 ± 4.2% in those with an incomplete circle when the MCA was occluded with a 6/0 nylon filament. When an 8/0 filament was used, no flow change in mice with a normal circle but a decrease to 60 ± 2% in those with an incomplete circle was observed. A flow drop to 63 ± 4% was also seen in Wistar rats when a 3/0 filament used. These data demonstrate that occlusion of the MCA by a thick filament may cause flow reduction in the hippocampus, which may be severe enough to lead to infarction if the circle of Willis is anomalous.