title: Cerebral Hemodynamics and Vascular Reactivity in Mild and Severe Ischemic Rodent Middle Cerebral Artery Occlusion Stroke Models.
abstract: Ischemia can cause decreased cerebral neurovascular coupling, leading to a failure in the autoregulation of cerebral blood flow. This study aims to investigate the effect of varying degrees of ischemia on cerebral hemodynamic reactivity using in vivo real-time optical imaging. We utilized direct cortical stimulation to elicit hyper-excitable neuronal activation, which leads to induced hemodynamic changes in both the normal and middle cerebral artery occlusion (MCAO) ischemic stroke groups. Hemodynamic measurements from optical imaging accurately predict the severity of occlusion in mild and severe MCAO animals. There is neither an increase in cerebral blood volume nor in vessel reactivity in the ipsilateral hemisphere (I.H) of animals with severe MCAO. The pial artery in the contralateral hemisphere (C.H) of the severe MCAO group reacted more slowly than both hemispheres in the normal and mild MCAO groups. In addition, the arterial reactivity of the I.H in the mild MCAO animals was faster than the normal animals. Furthermore, artery reactivity is tightly correlated with histological and behavioral results in the MCAO ischemic group. Thus, in vivo optical imaging may offer a simple and useful tool to assess the degree of ischemia and to understand how cerebral hemodynamics and vascular reactivity are affected by ischemia.
authors.affiliation: Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon 16419, Korea.
authors.forename: Jeongeun
authors.initials: J
authors.lastname: Sim
authors.affiliation: Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon 16419, Korea.
authors.forename: Areum
authors.initials: A
authors.lastname: Jo
authors.affiliation: Department of Biomedical Engineering, Sungkyunkwan University, Suwon 16419, Korea.
authors.forename: Bok-Man
authors.initials: BM
authors.lastname: Kang
authors.affiliation: Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon 16419, Korea.
authors.forename: Sohee
authors.initials: S
authors.lastname: Lee
authors.affiliation: Department of Neurology, Neuroscience Center, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea.; Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul 06351, Korea.
authors.forename: Oh Young
authors.initials: OY
authors.lastname: Bang
authors.affiliation: Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon 16419, Korea.
authors.forename: Chaejeong
authors.initials: C
authors.lastname: Heo
authors.affiliation: Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.
authors.forename: Gil-Ja
authors.initials: GJ
authors.lastname: Jhon
authors.affiliation: Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Korea.
authors.forename: Youngmi
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Center for Neuroscience Imaging Research (CNIR), Institute for Basic Science (IBS), Suwon 16419, Korea.; Department of Biomedical Engineering, Sungkyunkwan University, Suwon 16419, Korea.; Department of Health Sciences and Technology, SAIHST, Sungkyunkwan University, Seoul 06351, Korea.
authors.forename: Minah
authors.initials: M
authors.lastname: Suh
keywords: Arterial reactivity; Hemodynamics; MCAO model; Optical intrinsic signal imaging; Stroke