用频谱技术研究慢性传输型便秘的电生理信号

目的:探讨便秘模型中大鼠的结肠慢波变化 ,阐明体现肌电图与胃肠平滑肌电活动的相关性并为临床合理应用肌电图鉴别慢性便秘提供实验依据。通过传统生理记录仪记录及观测肌电和运动信号 ,不仅工作量大 ,而且不易对信号进行深入分析。本试验旨在研究利用计算机技术及频谱方法分析探讨大鼠的肌电活动和机械运动之间的关系。方法 :Wistar大鼠 4 0 (雌雄不限 ,每组 4 0只 )。以临床上常用的接触性泻剂大黄建立大鼠的“泻剂结肠”模型。利用体表电极、体内胃肠电极和压力传器 ,通过计算机分别同时记录正常对照组和便秘组大鼠体表胃电体内平滑肌慢波和胃平滑肌运动信号 ,并运用频谱方法进行数据处理和统计学分析。结果 :便秘组大鼠的结肠慢波的主功率 ,中心频率 ,平均频率和正常慢波的百分比均明显降低。P <0 .0 5 ;不稳定系数明显增加。体内慢波、结肠平滑肌的平均振幅相关性良好。结论 :结肠平滑肌的慢波振幅 ,频率降低是导致便秘的原因之一。体内慢波在一定程度能够反映肠道活动 ,提示其生理和病理规律 ,有可能应用于临床 ,作为胃肠动力性疾病的诊断和疗效判定的客观标准。计算机和频谱是电信号分析中的有效手段之一。

EXPERIMENTAL STUDY ON COLONIC ELECTROPHYSIOLOGY AND MOTILITY OF CATHARTIC COLON IN RATS

Objective:To find an appropriate interpretation of the EM (Gelectromyogram) prower changes in the patients suffered from constipation and demonstrate the ability of an adaptive spectral analysis method in detecting gastric dysrhythmic events from the EMG.Methods:To investigate the motility and electromyogram of cathartic colon,we fed the rats with rhubarb and phenolphthalein for 3 months.Simultaneous serosal and cutaneous recordings of gastric myoelectrical activity were made in 40 rats who were on examined the intestinal transit function and colonic electromyogram in different conditions in detecting gastric dysrhythmic events from the EMG.The dominant frequency and corresponding power of the recording were computed using the power spectral analysis method.Results:It was found that the freauency and amplitude of slow waves of colon in vivo decreased while lability coefficient increased.Statistical analysis demonstrated that the dominant power change from the EMG was correlated with that observed in the serosal recording (r=0.757, P =0.007).Conclusions:The change of the slow_wave amplitude is an important contributing factor of Slow Transit Constipation (STC).The adaptive spectral analysis approach has several advantages:narrow frequency peaks permitting more precise frequency indentificantion,determination of changes in frequency components at any time point,and enhanced interpretation of cutaneous EMG recordings.