One-stage apertura thoracis superior approach for four-vessel occlusion in rats

Abstract

【Abstract】Objective: There are a great number of modified models based on the four-vessel occlusion (4VO) model of Pulsinelli and Brierley which has been used world-wide for brain ischemia research. However, up to now the problems of collateral circulations of 4VO and the difficulty in arranging a surgery to occlude the basilar artery in other models are not satisfactorily solved yet. In this study, an improved 4-vessel occlusion (I4VO) rat model which is easy to handle and able to decrease the effect of collateral circu-lation is reported. Methods: The common carotid arteries and the begin-ning of the subclavical arteries of rats were occluded for different time by one-stage apertura thoracis superior approach. Neurological deficit scores defined by the modi-fied Garcia scoring system and histopathological method were used to evaluate the effects of this model up to 7 days after reperfusion. Results: The neurological scores in the 15-min and 25-min groups decreased significantly at 24, 48 and 72 hours after reperfusion (P<0.05), and the histopathologic study showed that there were stable, symmetrical changes of le-sions in bilateral hippocampus in all the ischemia samples from two ischemia groups compared with sham operated group (P<0.05). Conclusion: This modified model is safe, easy, reliable, stable, mini-invasive as well as time-saving in making bilat-eral hemispheric ischemia, which can effectively decrease collateral circulations and meanwhile lead to stable lesions in hippocampus and cortex. Key words: Collateral circulation; Brain ischemia; Hippocampus; Models, animal