应激对高血压大鼠认知障碍的影响及其机制

The Influence of stress on cognitive impairment of hypertensive rats and mechanism.

目的研究应激对高血压大鼠认知障碍的影响及机制。方法62只大鼠被随机分为应激组与非应激组、对照组,前2组用双肾双夹法制作高血压模型大鼠,其中应激组再接受强迫游泳应激。应激10周后以跳台实验测量大鼠的学习记忆能力,然后电镜下观察海马CA3区血管、神经元和突触结构的变化。结果①应激组大鼠血压较非应激组和对照组大鼠升高明显(P<0.05);②学习测验中,应激组跳台实验的错误次数和反应时间均高于非应激组和对照组(P<0.05);记忆测验中,应激组、非应激组和对照组的错误次数递减而潜伏期依次增加,两两差异均有统计学意义(P<0.05)。③应激组的海马C3区突触曲率、活性区长度和突触后膜致密物质厚度较非应激组小(P<0.05)。结论应激可能是血管性认知障碍的危险因素之一。

Objective To study the influence of stress on vascular cognitive impairment in hypertensive rats. Methods Sixty two rats were divided randomly into three groups： stress group, non-stress group and control group. Stress was induced by forcing rats to swim. At the end of 10 weeks after receiving stressor, the cognitive ability were evaluated by the step-down test and the pathological changes were examined under electron microscope. Results ①The blood pressure was much higher in stress group than in non-stress and control groups （P 〈 0.05）. ②The error times and response time were much higher in stress group than in non-stress group and control group （ P 〈 0.05 ）. When memory was test after 24 hours, the error times were higher and latency time was shorter in stress group than in non-stress group and control stress （P 〈 0. 05）. ③The synaptic interface curvature, synaptic active zone length and PSD were lower in stress group than in non-stress group （ P 〈 0. 05 ）. Conclusions Stress may be one of the risk factors for vascular cognitive impairment.