改善颈动脉狭窄所致认知功能障碍的实验研究

Removal of carotid artery stenosis improves stenosis-induced cognitive impairment in rat

目的研究解除颈动脉不完全狭窄后是否对不同程度颈动脉狭窄后所致认知功能障碍有治疗作用。方法用SD大鼠制作不同程度颈动脉狭窄模型,2周后将颈动脉狭窄解除,分别在解除2周、4周后各组进行水迷宫行为学检测、P300检测,同时取颈动脉狭窄处比较狭窄解除前后颈动脉横截面积狭窄率的变化。结果解除狭窄2、4周后对照组大鼠P300潜伏期、水迷宫实验逃避潜伏期均比假手术组大鼠明显延长,狭窄解除组大鼠的颈动脉面积狭窄率同对照组比较明显减少,并且P300潜伏期、水迷宫实验逃避潜伏期明显缩短。结论颈动脉狭窄可以导致认知功能障碍,同时认知功能障碍的程度与颈动脉狭窄程度呈正相关,并且解除颈动脉狭窄对轻度认知功能障碍有显著的治疗作用,并且随着解除时间延长认知功能障碍改善更加明显。

Objective To observe the effect of removing carotid artery stenosis on improving cognitive impairment induced by carotid artery stenosis of different degree in rats. Methods The animal model of carotid artery stenosis was established in 48 SD rats, 24 of severe stenosis and 24 of moderate stenosis （ the diameter of the carotid artery is respectively 0.45 mm and 0.6 mm）, and another rats underwent sham operation as normal control. Two weeks later, the removal of carotid artery stenosis was performed in half rats of severe stenosis and half of moderate stenosis, the left rat models as controls. In 2, 4 weeks after removal of stenosis, the change of cross section area of stenosis part was analyzed by calculating the value of [ 1 - Sstenosis/Snormal] , P300 event-related potential was detected and Morris water maze was performed. Results Two, four weeks after removal of stenosis, the P300 latency and the escape latency of Morris water maze in the control rats of severe and moderate stenosis was longer than that of sham operation group （ P 〈 0.01 ）, the value of [ 1 - Sstenosis/Snormal ] in the stenosis removal rats was less than the control of severe and moderate stenosis, with significantly less P300 latency and escape latency （P 〈0.01 ）. Conclusion Cognitive impairment is induced by carotid artery stenosis. The severer carotid artery stenosis is, the more the cognitive impairment is. Stenosis removal can improve mild cognitive impairment, and the effect is better on the 4^th week after stenosis removal than the 2^nd week.