脑缺血再灌流时脑温的动态改变

Dynamic changes of brain temperature in rat during cerebral ischemia and reperfusion

目的了解脑缺血再灌流后脑温的变化,为脑缺血动物的实验研究、以及亚低温脑保护作用机制提供理论依据。方法将SD大鼠分为四动脉阻断、双颈总动脉阻断、单侧颈总动脉阻断以及四动脉阻断10 min、20 min、30 min后再灌流组。用点式测温仪同时测量不同部位脑组织的温度。结果脑组织内存在温度梯度;脑缺血后同一时间点纹状体、海马和颞肌的温度不一致;不同程度脑缺血后脑温的变化不一致,双侧颈总动脉阻断的脑缺血中脑温的改变呈波浪状,单侧颈总动脉阻断的脑缺血中缺血侧脑温低于对照侧;四动脉阻断的全脑缺血中,缺血后不同时间开始再灌流脑温都有回升现象;脑缺血的严重程度和持续时间可影响动物的清醒和脑温的变化。结论本实验的结果说明了在脑缺血实验研究时采用连续监测、并将脑温控制在特定的范围内,避免脑缺血和再灌流期间脑温的波动影响实验结果的准确性。

Objective In order to study the neuroprotective effect of mild hypothermia on cerebral ischemia, brain temperature during cerebral ischemia and reperfusion were investigated. Methods Spra- gue-Dawley （SD） rats were divided into 6 groups： 4-vessels occlusion, bilateral common carotid arteries （CCA） occlusion, lateral CCA occlusion, reperfusion following 4-vessels occlusion at 10min, 20min and 30min intervals. Brain temperature were continuously simultaneously recorded at different brain regions. Results Temperature gradient exists in brain tissue. Brain temperature gradually decreases during cerebral ischemia. Brain temperature in ischemic hemisphere is lower than that in non-ischemic one as cere- bral ischemia is induced by lateral CCA occlusion. Brain temperature elevated transiently at the early stage of reperfusion, then decreased, and gradually returned to baseline as time of anesthesia passed. The severity and duration of cerebral ischemia can affect animal to regain consciousness and its brain tempera- ture. Condusions In order to get the accurately experimental results, it is necessary to continuously moni tor and control brain temperature at given pattern and avoid the fluctuation of brain temperature during cerebral ischemia.