大白鼠抗胃食管返流机制研究

Investigation of Anti-reflux Mechanism of Gastroesophageal Reflux in Rats

目的:为了探讨胃食管返流的拮抗机制。方法:对33只大白鼠进行食管测压.观测呼吸过程中胸腹内压力变化及其压力差,描记食管压力曲线图并了解其解剖结构。结果:大白鼠腹段食管相对较长,呼吸过程中腹内压力始终高于胸内压力。压力曲线图上可见食管下端括约肌压力(LESP)和隔肌脚对食管的关闭压力(DPP),前者呈平台状,为食管下段括约肌形成的高压带,后者呈波浪形,波动频率与呼吸频率一致,两者间的距离等于腹段食管长度,为膈肌收缩挤压食管所致。本组实验动物中同时存在 LESP 和 DPP 者占48.5%,仅见 LESP 或 DPP 者占18.2%和33.3%。LESP 和 DPP 的压力均值为2.32±1.133kPa(17.4±8.5mmHg)和2.24±1.04kPa(16.8±7.8mmHg),高于隔肌两侧压力差。结论:食管下段括约肌膈肌脚的收缩对胃食管返流均有拮抗作用。大白鼠腹段食管较长,是研究胃食管返流的理想模型。

Objective:To investigate the anti-reflux mechanism of gastroesophageal reflux. Methords:Thirty-three rats were studied by the pull-through pattern manometry of the esopha- gus,including pressures in the thorax and abdomen segments,and the pressure profile during the respiratory circles the pressure gradiant.Results:The length of the intra-abdominal segment (LIAS)of the esophagus in rats appeared longer than that in human being,the permanent positive pressure gradiant existing between the throax and abdomen and the double-plateau pattern(LESP and DPP)were recorded in the pressure profiles.LESP(lower esophageal sphincter pressure)was detected as a wide flat form wave.DPP(diaphragmatic pinch-cock pressure)consisted of a group of rapid positive oscillation waves with a frequency in accordance with the respiratory rates.The distance of LESP-to-DPP had the same length as LIAS,it is caused by diaphragmatic pinch-cock pressure.In 16/33(48.5%)rats,both the LESP and the DPP were recorded,whereas in 6/33 (18.2%)rats the LESP was recorded,and in 11/33(33.3%)rats only the DPP was recorded. The pressures of LESP and DPP were 2.32±1.133kPa and 2.24±1.04kPa respectively,both were much higher than the positive pressure existing between both sides of the diaphragm.Con- clusions:Not only the lower esophageal segment(LES)plays an important role in anti-reflux,but also diaphragmatic crural slings do.Because the LIAS is longer in rats,so one can make a better model with rats for the study of gastroesophageal reflux.