Department of Neurology, Southwest Hospital, Third Military Medical University, Shapingba, Chongqing 400038, PR China.
Neuroscience. 2012 Sep 6;219:137-44. doi: 10.1016/j.neuroscience.2012.05.060. Epub 2012 Jun 4.
Carotid artery stenosis appears to be an independent risk factor for cognitive impairment. But the mechanisms of cognitive impairments occurring in patients with asymptomatic carotid stenosis are poorly understood. One important reason is the absence of a good carotid stenosis model. In the present study, after establishing different degrees of carotid stenosis models in aged rats successfully, we investigated their cognitive function. Wistar rat models with carotid artery stenosis were established by ligating the common carotid artery along with various gauges of needle and then removing the needle. The cognitive performance was assessed using Morris water maze (MWM) task. Cholinergic markers like acetylcholine (ACh) were evaluated in hippocampus. Neuronal damage was also studied through morphological changes. Severe carotid stenosis led to impairment in learning ability and memory retrieval, accompanied with a decrease in ACh level and morphological damage in hippocampus. Moderate carotid stenosis rats had a partial cognitive impairment, but there were no changes in ACh level and morphological damage in hippocampus. Meanwhile, mild carotid stenosis rats had no cognitive impairment compared to sham-operated rats. The results of this study suggest that different degrees of carotid stenosis induce different cognitive changes in aged rats.
颈动脉狭窄似乎是认知障碍的一个独立危险因素。但是，无症状性颈动脉狭窄患者发生认知障碍的机制尚不清楚。一个重要原因是缺乏良好的颈动脉狭窄模型。在本研究中，我们成功建立了不同程度的老年大鼠颈动脉狭窄模型，并研究了它们的认知功能。通过用不同规格的针结扎颈总动脉并取出针，建立了大鼠颈动脉狭窄模型。通过 Morris 水迷宫（MWM）任务评估认知表现。在海马中评估胆碱能标志物如乙酰胆碱（ACh）。通过形态变化研究神经元损伤。严重的颈动脉狭窄导致学习能力和记忆检索受损，同时伴随着海马中 ACh 水平和形态损伤的降低。中度颈动脉狭窄大鼠存在部分认知障碍，但海马中 ACh 水平和形态损伤没有变化。同时，与假手术大鼠相比，轻度颈动脉狭窄大鼠没有认知障碍。本研究结果表明，不同程度的颈动脉狭窄会导致老年大鼠产生不同程度的认知变化。
