Middle Cerebral Artery Occlusion in Rats : Evaluation of the Model With or Without Craniectomy

ABSTRACT

The purpose of our present study was to asses the effectiveness of middle cerebral artery occlusion in producing acute focal cerebral ischemia in rats by use of Bederson's or Longa's method in which occlusion was performed with or without craniectomy respectively. In twenty-nine Sprague-Dawley rats weighing 250-300 gm, right middle cerebral artery occlusion was achieved by use of either Bederson's method or Long's method. After 4 hours of ischemia, neurological evaluation was performed and then brain water content was determined in the central, intermediate, and outer zones of each cortical mantle. in both groups, a significant neurological deficit caused by focal cerebral ischemia was observed. More severe neurological deficit was achieved by Longa's method than by Bederson's method(p<0.001). In Bederson's method group, significant brain edema was observed only in the ischemic central and intermediate zones. However, in Longa's method group, significant brain edema was observed in all of the three ischemic zones. And more severe brain edema was achieved by Long's method in each of three ischemic zones than by Bederson's method(p<0.001, respectively). Theses results incicate that Longa's method is more effective and persistent method in producing acute focal cerebral ischemia than Bederson's method. Longa's method is considered as one of a good, less invasive, and technically easy method to achieve focal cerebral ischemia in rats.