title: Spatial and temporal MRI profile of ischemic tissue after the acute stages of a permanent mouse model of stroke.
abstract: OBJECTIVE
  To characterize the progression of injured tissue resulting from a permanent focal cerebral ischemia after the acute phase, Magnetic Resonance Imaging (MRI) monitoring was performed on adult male C57BL/6J mice in the subacute stages, and correlated to histological analyses.
  
  
  METHODS
  Lesions were induced by electrocoagulation of the middle cerebral artery. Serial MRI measurements and weighted-images (T2, T1, T2* and Diffusion Tensor Imaging) were performed on a 9.4T scanner. Histological data (Cresyl-Violet staining and laminin-, Iba1- and GFAP-immunostainings) were obtained 1 and 2 weeks after the stroke.
  
  
  RESULTS
  Two days after stroke, tissues assumed to correspond to the infarct core, were detected as a hyperintensity signal area in T2-weighted images. One week later, low-intensity signal areas appeared. Longitudinal MRI study showed that these areas remained present over the following week, and was mainly linked to a drop of the T2 relaxation time value in the corresponding tissues. Correlation with histological data and immuno-histochemistry showed that these areas corresponded to microglial cells.
  
  
  CONCLUSIONS
  The present data provide, for the first time detailed MRI parameters of microglial cells dynamics, allowing its non-invasive monitoring during the chronic stages of a stroke. This could be particularly interesting in regards to emerging anti-inflammatory stroke therapies.
authors: University Orsay Paris-sud, IR4M, UMR 8081, Bat 220, Orsay, F-91405, France ; CNRS, Orsay, F-91405, France.
authors: A
authors: A
authors: Bogaert-Buchmann
authors: M
authors: M
authors: Poittevin
authors: C
authors: C
authors: Po
authors: D
authors: D
authors: Dupont
authors: C
authors: C
authors: Sebrié
authors: Y
authors: Y
authors: Tomita
authors: A
authors: A
authors: Trandinh
authors: J
authors: J
authors: Seylaz
authors: E
authors: E
authors: Pinard
authors: P
authors: P
authors: Méric
authors: N
authors: N
authors: Kubis
authors: B
authors: B
authors: Gillet
keywords: Mouse; NMR Imaging.; microglia; permanent cerebral ischemia; stroke