title: Assessment of Blood-Brain Barrier Permeability by Dynamic Contrast-Enhanced MRI in Transient Middle Cerebral Artery Occlusion Model after Localized Brain Cooling in Rats.
abstract: The purpose of this study was to evaluate the effects of localized brain cooling on blood-brain barrier (BBB) permeability following transient middle cerebral artery occlusion (tMCAO) in rats, by using dynamic contrast-enhanced (DCE)-MRI.
  
  
  
  Thirty rats were divided into 3 groups of 10 rats each: control group, localized cold-saline (20℃) infusion group, and localized warm-saline (37℃) infusion group. The left middle cerebral artery (MCA) was occluded for 1 hour in anesthetized rats, followed by 3 hours of reperfusion. In the localized saline infusion group, 6 mL of cold or warm saline was infused through the hollow filament for 10 minutes after MCA occlusion. DCE-MRI investigations were performed after 3 hours and 24 hours of reperfusion. Pharmacokinetic parameters of the extended Tofts-Kety model were calculated for each DCE-MRI. In addition, rotarod testing was performed before tMCAO, and on days 1-9 after tMCAO. Myeloperoxidase (MPO) immunohisto-chemistry was performed to identify infiltrating neutrophils associated with the inflammatory response in the rat brain.
  
  
  
  Permeability parameters showed no statistical significance between cold and warm saline infusion groups after 3-hour reperfusion 0.09 ± 0.01 min(-1) vs. 0.07 ± 0.02 min(-1), p = 0.661 for K(trans); 0.30 ± 0.05 min(-1) vs. 0.37 ± 0.11 min(-1), p = 0.394 for kep, respectively. Behavioral testing revealed no significant difference among the three groups. However, the percentage of MPO-positive cells in the cold-saline group was significantly lower than those in the control and warm-saline groups (p < 0.05).
  
  
  
  Localized brain cooling (20℃) does not confer a benefit to inhibit the increase in BBB permeability that follows transient cerebral ischemia and reperfusion in an animal model, as compared with localized warm-saline (37℃) infusion group.
authors: Department of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang 14068, Korea.
authors: Eun Soo
authors: ES
authors: Kim
authors: Department of Radiology, Yonsei University College of Medicine, Seoul 03722, Korea.
authors: Seung-Koo
authors: SK
authors: Lee
authors: Department of Pathology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang 14068, Korea.
authors: Mi Jung
authors: MJ
authors: Kwon
authors: Department of Neurology, Yonsei University College of Medicine, Seoul 03722, Korea.
authors: Phil Hye
authors: PH
authors: Lee
authors: Department of Industrial Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang 14068, Korea.
authors: Young-Su
authors: YS
authors: Ju
authors: Department of Radiology, Hallym University Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul 05355, Korea.
authors: Dae Young
authors: DY
authors: Yoon
authors: Department of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul 07441, Korea.
authors: Hye Jeong
authors: HJ
authors: Kim
authors: Department of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang 14068, Korea.
authors: Kwan Seop
authors: KS
authors: Lee
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000502:physiology*; D001921:Brain / Q000000981:diagnostic imaging; D004195:Disease Models, Animal; D007036:Hypothermia, Induced / Q000379:methods*; D020244:Infarction, Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology*; D002546:Ischemic Attack, Transient / Q000000981:diagnostic imaging / Q000503:physiopathology; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D010539:Permeability; D017207:Rats, Sprague-Dawley; D015427:Reperfusion Injury / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000517:prevention & control; D012965:Sodium Chloride
chemical_list: D012965:Sodium Chloride
keywords: Blood-brain barrier; Brain; DCE-MRI; Dynamic contrast-enhanced-MRI; Ischemia; Middle cerebral artery; Permeability