title: Focal Ischemic Injury with Complex Middle Cerebral Artery in Stroke-Prone Spontaneously Hypertensive Rats with Loss-Of-Function in NADPH Oxidases.
abstract: By means of introgressing a loss-of-function mutation in the p22phox gene from the Matsumoto Eosinophilia Shinshu (MES) rat to stroke-prone spontaneously hypertensive rats (SHRSP), we constructed the SHRSP-based congenic strain lacking the P22PHOX expression (i.e., lacking NADPH oxidases [NOX] activities) (SHRSP.MES-Cyba(mes)/Izm; hereafter referred to as SP.MES). To examine the effects of Nox activities on the focal ischemic injury or stroke, we performed middle cerebral artery (MCA) occlusion in this new congenic strain; the distal MCA was occluded by 561-nm laser-driven photothrombosis. Resting mean arterial blood pressure was significantly lower in SP.MES when compared with the control PM0/SHRSP (150±11 mmHg vs. 166±11 mmHg). Cerebral blood flow decreased to 37±13% in SP.MES and 35±17% in PM0/SHRSP at 10 min after MCA occlusion (not significant). Infarct volume determined at 24 h after MCA occlusion in SP.MES was 89±39 mm3, which was not significantly different from 83±35 mm3 in PM0/SHRSP. The distal MCA pattern was more complex in SP.MES (median 3, IQR 3-5) than PM0/SHRSP (median 2, IQR 1-3) (p = 0.001). Because more complex distal MCA is known to produce larger infarction after distal MCA occlusion in SHR, we adjusted for the branching pattern in an ANCOVA. The adjusted mean of infarct volume was significantly smaller in SP.MES compared with that in PM0/SHRSP (67 [95% CI 46 to 87] mm3 vs. 100 [95% CI 82 to 118] mm3, p = 0.032). Elimination of the P22PHOX expression induced complex distal MCA, which would suggest the presence of 'loss of complexity' induced by enhanced oxidative stress in SHRSP; infarct size in SP.MES--when adjusted for distal MCA complexity--was significantly attenuated compared with that in PM0/SHRSP. Therefore, the present results suggest that Nox is harmful for ischemic brain tissue.
authors.affiliation: Laboratory for Neurochemistry, National Hospital Organization Hizen Psychiatric Center, Saga, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yao
authors.affiliation: Department of Functional Pathology, Shimane University School of Medicine, Izumo, Japan.
authors.forename: Mohammed Zubaerul
authors.initials: MZ
authors.lastname: Ferdaus
authors.affiliation: Department of Functional Pathology, Shimane University School of Medicine, Izumo, Japan.
authors.forename: Hasan Md
authors.initials: HM
authors.lastname: Zahid
authors.affiliation: Department of Functional Pathology, Shimane University School of Medicine, Izumo, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Ohara
authors.affiliation: Laboratory for Neurochemistry, National Hospital Organization Hizen Psychiatric Center, Saga, Japan.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Nakahara
authors.affiliation: Department of Functional Pathology, Shimane University School of Medicine, Izumo, Japan.
authors.forename: Toru
authors.initials: T
authors.lastname: Nabika
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure; D001835:Body Weight; D001921:Brain / Q000098:blood supply / Q000378:metabolism / Q000473:pathology; D020520:Brain Infarction / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology; D002545:Brain Ischemia / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D002560:Cerebrovascular Circulation; D020244:Infarction, Middle Cerebral Artery / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D020768:Middle Cerebral Artery / Q000378:metabolism* / Q000503:physiopathology; D009154:Mutation; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism*; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D020521:Stroke / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology
chemical_list: D019255:NADPH Oxidases; C515768:Cyba protein, rat