目的:观察不同频率电针预处理"膻中""内关"穴对家兔急性心肌缺血时心脏功能活动的影响,分析其是否对家兔急性心肌缺血有保护作用.方法:通过结扎冠状动脉左前降支复制家兔急性心肌缺血模型,BL-420F生物机能实验系统测量家兔左心室收缩压(LVSP)、左心室舒张末压(LVEDP)及心率.结果:模型对照组家兔左心室收缩压降低、左心室舒张末压升高、心率减慢,与空白对照组比较差异有统计学意义(P<0.05),提示心脏收缩、舒张功能障碍;高频电针组左心室收缩压和左心室舒张末压降低,心率加快,与模型对照组比较差异有统计学意义(P<0.05),中频电针组左心室收缩压和心率加快,与模型对照组比较差异有统计学意义(P<0.05),低频电针组左心室收缩压、左心室舒张末压及心率与模型对照组比较差异无统计学意义(P>0.05).结论:在家兔急性心肌缺血时,高频电针预处理膻中、内关穴能改善心脏收缩和舒张功能状态,中频电针预处理对心脏收缩功能有改善作用,低频电针预处理对心功能影响不明显.

To determine whether the pathological changes caused by injury to the spinal cord can be correlated with values obtained by the Magnetic Motor Evoked Potential (MEPs) technique, we studied spinal cords from 41 adult cats who were divided into 4 groups. The groups ranged from normal cats whose spinal cords were not compressed, to slightly, moderately and severely injured. MEPs were recorded before compression and in 30 minutes, 6 hours, 1 week, 2 week and 4 week after the compression unit was installed. Pathological changes with increased pressure were seen in blood vessels, nerve cells and fibers, Nissl substance and the central canal. A reversal of pathological changes was observed in slight or moderate injury during the 4 weeks of the experiment. Extensive injury, however, caused irreversible changes in the nerve cells with loss of motor function. The latency of MEPs at 30 minutes and 6 hours in the slightly injured group was 0.37 and 0.38 times greater than the baseline and returned to normal levels in 4 weeks. In the moderately injured group, the latency was increased 0.77 and 0.81 times and in the severely injured 1.32 and 1.36 times over the baseline. Recovery in the second group was partial and not at all in the severely injured. Thus, there appears to be good correlation between observed pathological changes, motor functions and MEPs.