大鼠局灶性脑缺血对自主神经系统的影响

目的：研究心脏自主神经功能在急性局灶性脑缺血及再灌注后的变化情况。方法：通过线栓法建立大鼠局灶性脑缺血再灌注模型，连续记录大鼠局灶性脑缺血再灌注不同时间段的动脉血压、心电图信号以及心率．比较分析缺血组缺血后各时段与假手术组相应时段缺血前后以及再灌注前后的动脉血压、心率以及心率变异性的变化。结果：急性脑缺血组动脉血压、心率较假手术组均显著升高，心率变异性的能量有较大的变化；再灌注后，动脉血压、心率及心率变异性均有不同程度的恢复。而且缺血时间越短，恢复越快。结论：在急性脑缺血后，心脏自主神经活动减弱．而交感神经活动相对增强或者迷走神经活动减弱。

Changes in Autonomic Nervous System following Focal Cerebral Ischemia in SD Rats

Objective: To investigate the changes in autonomic nervous system following focal cerebral ischemia in rats. Methods: Focal cerebral ischemia/reperfusion in SD rats was induced by intraluminal occlusion of middle cerebral artery. Arterial blood pressure (ABP), electrocardiogram (ECG) and heart rate (HR) were collected (PowerLab, AD Instruments) and estimated. The heart rate variability (HRV) sequences were measured by power spectral analysis through the Fast Fourier Transform (FFT). Paired t-tests were performed for all of groups. Results: ABP and HR were obviously increased after ischemia vs sham-operation. After reperfusion, ABP and HR as well as HRV were recovered to different extent and the longer the ischemia period, the slower the speed of recovery. Conclusion: It is suggested that the autonomic nervous activity should be weakened, however, the sympathetic nerve activity be relatively greater than the vagal activity after acute focal cerebral ischemia.