title: Cerebral watershed infarcts may be induced by hemodynamic changes in blood flow.
abstract: OBJECTIVE
  A watershed infarct is defined as an ischemic lesion at the border zones between territories of two major arteries. The pathogenesis of watershed infarcts, specifically whether they are caused by hemodynamic or embolic mechanisms, has long been debated. In this study, we aimed to examine whether watershed infarcts can be induced by altering the hemodynamic conditions in rats.
  
  
  METHODS
  In phase one, to determine the proper clamping duration for a reproducible infarct, 30 rats were equally divided into 5 subgroups and underwent bilateral common carotid artery (CCA) clamping for different durations (0.5, 1.0, 1.5, 2.0, and 3.0 hours). In phase two, to analyze the types of infarcts induced by bilateral CCA clamping, 40 rats were subjected to bilateral CCA clamping for 2 hours. As a control, 8 rats underwent all the operation procedures except bilateral CCA clamping. We performed 7.0T magnetic resonance imaging on the surviving rats on the second day to evaluate the extent of the infarcts. We further identified and examined the infarcts with brain slices stained using 2, 3, 5-triphenyltetrazolium chloride (TTC) on the third day.
  
  
  RESULTS
  After 2 hours of bilateral CCA clamping, cerebral infarction occurred in 42% of surviving rats (13/31). The majority of the ischemic lesions were located in watershed regions of the brain, demonstrated by both MRI and TTC staining.
  
  
  CONCLUSIONS
  Watershed infarcts were induced through changing hemodynamic conditions by bilateral CCA clamping in rats. This method may lead to the development of a reliable rodent model for watershed infarcts.
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.
authors.forename: Jingfei
authors.initials: J
authors.lastname: Shi
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.|b Department of Neurology , Xuanwu Hospital, Capital Medical University , Beijing , China.
authors.forename: Ran
authors.initials: R
authors.lastname: Meng
authors.affiliation: c Department of Neurosurgery , Geisinger Health System , Danville , PA , USA.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Konakondla
authors.affiliation: d Department of Neurosurgery , Wayne State University School of Medicine , Detroit , MI , USA.
authors.forename: Yuchuan
authors.initials: Y
authors.lastname: Ding
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.
authors.forename: Yunxia
authors.initials: Y
authors.lastname: Duan
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.
authors.forename: Di
authors.initials: D
authors.lastname: Wu
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.
authors.forename: Bincheng
authors.initials: B
authors.lastname: Wang
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.
authors.forename: Yinghao
authors.initials: Y
authors.lastname: Luo
authors.affiliation: a China-America Joint Institute for Neuroscience, Xuanwu Hospital, Capital Medical University, Beijing Institute for Brain Disorders , Beijing , China.|e Department of Neurosurgery , Xuanwu Hospital, Capital Medical University , Beijing , China.
authors.forename: Xunming
authors.initials: X
authors.lastname: Ji
mesh_terms: D000818:Animals; D001921:Brain / Q000098:blood supply* / Q000473:pathology; D002339:Carotid Arteries / Q000187:drug effects; D002544:Cerebral Infarction / Q000188:drug therapy / Q000503:physiopathology*; D004195:Disease Models, Animal; D006439:Hemodynamics; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D017207:Rats, Sprague-Dawley; D013778:Tetrazolium Salts / Q000627:therapeutic use
chemical_list: D013778:Tetrazolium Salts; C009591:triphenyltetrazolium
keywords: Rat; bilateral CCA clamping; magnetic resonance imaging; stroke