串脉冲致兔隔肌疲劳的动物模型

本实验采用串脉冲刺激兔隔神经法复制了家兔膈肌疲劳模型。测定隔肌张力（Ｔｄｉ）、跨膈压（Ｐｄｉ）及其频率特性（Ｔｄｉ－Ｆ、Ｐｄｉ－Ｆ）、呼吸流速（Ｖ）、肺阻力（ＲＬ）、膈肌肌电图（ＥＭＧｄｉ等作为评价膈肌收缩力量的指标。结果发现：经串脉冲刺激后，Ｐｄｉ－Ｆ曲线在３０、５０和１００Ｈｚ时显著降低，Ｐｄｉ、Ｔｄｉ、Ｖ和跨肺压均显著下降。氨茶碱可增加隔肌收缩力，延缓膈肌疲劳过程。结果提示，用串脉冲刺激兔膈神经法建立的模型是一种灵敏、可靠和稳定的膈肌疲劳动物模型。

A MODEL OF DIAPHRAGMATIC FATIGUE INDUCED BY TRAIN PULSE STIMULATION IN RABBITS

A method for producing diaphragmatic fatigue in anesthetized rabbits by bilateral cervicalphrenic nerve stimulation with train pulse was developed.The diaphragmatic strength was as-sessed from transdiaphragmatic pressure(Pdi),diaphragmatic tension(Tdi),Pdi(orTdi)-stimulus frequency(10,20,30,50 and 100Hz)relationships,electromyography of the dia-phragm and respiratory mechanical functions,e. g.flow rate(V)and lung resistance(R_L),Afterdiaphragmatic fatigue produced by the 15-minute stimulation with train pulse,Pdi-freq uencycurve and Tdi-freq uency curve were significantly reduced at 30,50 and 100 Hz. Pdi,Tdi,V andtranspulmonary pressure were significantly decreased.After aminophylline administration,Pdiand Tdi significantly increased at 30,50 and 100 Hz in dose-dependent manner and the changesof Pdi,Tdi,V and R_L in 15-minute fatigue stimulation were decreased.These suggested thataminophylline could enhance the contractility of diaphragm in rabbits.It is considered that thediaphragmatic fatigue induced by bilateral phrenic stimulation with train pulse is a useful and re-liable model of diaphragmatic fatigue in rabbits for testing the drugs of anti-diaphragmatic fa-tigue.