Article

Photochemically induced cerebral ischemia in a mouse model.

Department of Neurosurgery, Chonnam National University Hospital, Gwangju 501-757, South Korea. <>
Surgical Neurology (impact factor: 1.67). 07/2007; 67(6):620-5; discussion 625. DOI:10.1016/j.surneu.2006.08.077 pp.620-5; discussion 625
Source: PubMed

ABSTRACT MCAO has been widely used to produce ischemic brain lesions. The lesions induced by MCAO tend to be variable in size because of the variance in the collateral blood supply found in the mouse brain.
We modified the rat photothrombosis model for use in mice. Male C57BL/6 mice were subjected to focal cerebral ischemia by photothrombosis of cortical microvessels. Cerebral infarction was produced by intraperitoneal injection of rose bengal, a photosensitive dye, and by focal illumination through the skull. Motor impairment was assessed by the accelerating rotarod and staircase tests. The brain was perfusion fixed for histologic determination of infarct volume 4 weeks after stroke.
The lesion was located in the frontal and parietal cortex and the underlying white matter was partly affected. A relatively constant infarct volume was achieved 1 month after photothrombosis. The presence of the photothrombotic lesion significantly impaired the motor performance as measured by the rotarod and staircase tests. Our findings show that photothrombotic infarction in mice is highly reproducible in size and location.
This procedure can provide a simple model of cerebral infarction for a unilateral motor cortex lesion. In addition, it can provide a suitable model for the study of potential neuroprotective and therapeutic agents in human stroke.

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    Article: Controlling the volume of the focal cerebral ischemic lesion through photothrombosis
    Tiannan Wang, Wenju Cui, Yicheng Xie, Weiping Zhang, Shinghua Ding
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    Am. J. Biomed. Sci. Am. J. Biomed. Sci. 01/2010; 2(2):33-42.
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    Lingfeng Yu, Elaine Nguyen, Gangjun Liu, Bernard Choi, Zhongping Chen
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    ABSTRACT: We report the use of spectral Doppler optical coherence tomography imaging (SDOCTI) for quantitative evaluation of dynamic blood circulation before and after a localized ischemic stroke in a mouse model. Rose Bengal photodynamic therapy (PDT) is used as a noninvasive means for inducing localized ischemia in cortical microvasculature of the mouse. Fast, repeated Doppler optical coherence tomography scans across vessels of interest are performed to record flow dynamic information with high temporal resolution. Doppler-angle-independent flow indices are used to quantify vascular conditions before and after the induced ischemia by the photocoagulation of PDT. The higher (or lower) flow resistive indices are associated with higher (or lower) resistance states that are confirmed by laser speckle flow index maps (of laser speckle imaging). Our in vivo experiments shows that SDOCTI can provide complementary quantified flow information that is an alternative to blood volume measurement, and can be used as a means for cortical microvasculature imaging well suited for small animal studies.
    Journal of Biomedical Optics 15(6):066006. · 3.16 Impact Factor
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Keywords

accelerating rotarod
 
cerebral infarction
 
collateral blood supply
 
constant infarct volume
 
focal cerebral ischemia
 
human stroke
 
infarct volume 4 weeks
 
intraperitoneal injection
 
ischemic brain lesions
 
lesions induced
 
mouse brain
 
parietal cortex
 
photosensitive dye
 
photothrombotic infarction
 
potential neuroprotective
 
rat photothrombosis model
 
simple model
 
suitable model
 
underlying white matter
 
unilateral motor cortex lesion