(Stroke. 2000;31:2245.)
© 2000 American Heart Association, Inc.
Original Contributions |
A New Model of Cerebral Microthrombosis in Rats and the Neuroprotective Effect of a Rho-Kinase Inhibitor
From Laboratory for Pharmacology, Asahi Chemical Industry, Shizuoka, Japan.
Correspondence to Yoshinori Toshima, MS, Laboratory for Pharmacology, Asahi Chemical Industry, 632–1, Mifuku, Ohito-cho, Tagata-gun, Shizuoka 410-2321, Japan. E-mail a9187022{at}ut.asahi-kasei.co.jp
Background and Purpose—The aim of this study was to develop a new model of stroke based on endothelial damage and thrombotic occlusion in a perforating artery, leading to small cerebral infarcts and neurological deficits in rats. Moreover, the neuroprotective efficacy of fasudil, a rho-kinase inhibitor, was investigated in this model.
Methods—Fifty-six male Sprague-Dawley rats were used in the present study. Rats were anesthetized with sodium pentobarbital, and 100 µg of sodium laurate was injected into the left internal carotid artery on days 1 and 3. The thrombus induction and consequent of ischemic brain damage were examined by histopathological analyses and neurological deficit scoring in a posture reflex test. To investigate the neuroprotective effects of fasudil, 1 or 10 mg/kg was administered intraperitoneally 5 minutes after the first injection of sodium laurate and once daily thereafter on the following 2 days.
Results—One hour after the injection of sodium laurate, microscopic examination of phosphotungstic acid hematoxylin–stained sections (n=5) revealed that microthrombi containing fibrin strands obstructed the perforating arteries in the ipsilateral hemisphere. Under a transmission electron microscope (n=6), endothelial cells appeared exfoliated and the vascular lumen was obstructed by a thrombus composed of degranulated platelets, fibrin, leukocytes, and erythrocytes. No evidence of endothelial cell damage or thrombus could be found in the ipsilateral side of the pial artery (middle cerebral artery). Twenty-four hours after the second injection of sodium laurate (day 4), 13 of 15 rats (86.6%) showed mild to severe neurological deficits. Multiple small cerebral infarcts were observed in the hippocampus, cortex, and thalamus. Treatment with fasudil (1 and 10 mg/kg, n=15 each) resulted in a significant improvement in neurological deficits. Fasudil also significantly reduced the area of cerebral infarction.
Conclusions—We present a new model of stroke in rats, in which the perforating arteries are selectively occluded by microthrombi. This model is useful to investigate the pathophysiology and treatment of small cerebral infarction, which is caused by perforating arterial occlusive diseases such as lacunar infarcts. Fasudil may be beneficial in the treatment of acute ischemic stroke.
Editorial Comment
Department of Neurological Surgery, University of Miami School of Medicine, Miami, Florida
This article has been cited by other articles:
 |
|
 |
|
  E. L. Bailey, J. McCulloch, C. Sudlow, and J. M. Wardlaw Potential Animal Models of Lacunar Stroke: A Systematic Review Stroke, June 1, 2009; 40(6): e451 - e458. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H.-W. Wang, P.-Y. Liu, N. Oyama, Y. Rikitake, S. Kitamoto, J. Gitlin, J. K. Liao, and W. A. Boisvert Deficiency of ROCK1 in bone marrow-derived cells protects against atherosclerosis in LDLR-/- mice FASEB J, October 1, 2008; 22(10): 3561 - 3570. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Yin, K.-i. Morishige, T. Takahashi, K. Hashimoto, S. Ogata, S. Tsutsumi, K. Takata, T. Ohta, J. Kawagoe, K. Takahashi, et al. Fasudil inhibits vascular endothelial growth factor-induced angiogenesis in vitro and in vivo Mol. Cancer Ther., May 1, 2007; 6(5): 1517 - 1525. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Noma, N. Oyama, and J. K. Liao Physiological role of ROCKs in the cardiovascular system Am J Physiol Cell Physiol, March 1, 2006; 290(3): C661 - C668. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Shimokawa and A. Takeshita Rho-Kinase Is an Important Therapeutic Target in Cardiovascular Medicine Arterioscler Thromb Vasc Biol, September 1, 2005; 25(9): 1767 - 1775. [Abstract] [Full Text] [PDF]
|
|