Characterizing photothrombotic distal middle cerebral artery occlusion and YAG laser-induced reperfusion model in the Izumo strain of spontaneously hypertensive rats.
No study has systematically studied the relevance of original Izumo strain of spontaneously hypertensive rats (SHR/Izm) as a stroke model. Furthermore, both SHR/Izm and stroke-prone SHR/Izm (SHRSP/Izm) are commercially available, and recent progress in genetic studies allowed us to use several congenic strains of rats constructed with SHR/Izm and SHRSP/Izm as the genetic background strains. A total of 166 male SHR/Izm and 17 male SHRSP/Izm were subjected to photothrombotic middle cerebral artery (MCA) occlusion with or without YAG laser-induced reperfusion. The pattern of distal MCA was recorded. Infarct volumes were determined with 2,3,5-triphenyltetrazolium chloride. At 24 or 48 h after MCA occlusion, infarct volumes in the permanent occlusion and 2-h occlusion groups (88 ± 22 [SD] and 87 ± 25 mm³, respectively) were significantly larger than that in the 1-h occlusion group (45 ± 14 mm³), indicating the presence of sizeable zone of penumbra. Infarct size in SHRSP/Izm determined at 24 h after MCA occlusion was fairly large (124.0 ± 34.8 mm³, n = 10). Infarct volume in SHR/Izm with simple distal MCA was 76 ± 19 mm³, which was significantly smaller than 95 ± 22 mm³ in the other SHR/Izm with more branching MCA. These data suggest that this stroke model in SHR/Izm is useful in the preclinical testing of stroke therapies and elucidating the pathophysiology of cerebral ischemia/reperfusion.
Yao
Hiroshi
H
National Hospital Organization Hizen Psychiatric Center, Saga, Japan. hyao@hizen2.hosp.go.jp
Nabika
Toru
T
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology / Q000528:radiation effects; D004195:Disease Models, Animal; D020244:Infarction, Middle Cerebral Artery / Q000473:pathology* / Q000532:radiotherapy*; D053844:Lasers, Solid-State / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000379:methods; D008297:Male; D020768:Middle Cerebral Artery / Q000503:physiopathology; D051381:Rats; D011918:Rats, Inbred SHR; D015424:Reperfusion / Q000295:instrumentation / Q000379:methods*