Abstract: Objective This study aimed to improve the experimental setup for investigating factors influencing respiratory motor regulation. The objective was to achieve real-time synchronous recording of phrenic nerve discharge, diaphragmatic muscle discharge, and respiratory movement in rabbits, and to calculate the time difference between phrenic nerve discharge and diaphragmatic muscle discharge (ΔT1) , as well as the time difference between diaphragmatic muscle discharge and the start of the respiratory curve ( ΔT2 ) . Method The phrenic nerve and diaphragmatic muscle of rabbits were isolated, and tracheal intubation was performed. The BL-420I information-integrated signal acquisition and processing system was used to simultaneously record the curves of phrenic nerve discharge, diaphragmatic muscle discharge, and respiratory movements under normal physiological state and different interventions ( increasing the null lumen, increasing the concentration of CO2 , intravenous injection of lactic acid solution at the ear margin, cutting the vagus nerve and stimulating the vagus nerve at the central end) . ΔT1 and ΔT2 were calculated, and 30 respiratory cycles were statistically analyzed. Result The synchronization curves of phrenic nerve discharge, diaphragmatic discharge and respiratory movement were recorded simultaneously under normal physiological state and various intervention conditions by applying BL-420I. Under normal physiological state, ΔT1 = ( 32. 95±5. 34) ms, ΔT2 = ( 0. 366±0. 028) s; after increasing the null lumen, ΔT1 = (28. 63±5. 72)ms, ΔT2 = (0. 295±0. 020) s; after inhalation of CO2 , ΔT1 = ( 20. 72 ± 5. 51) ms,ΔT2 = ( 0. 250 ± 0. 016 ) s; After intravenous injection of lactate, the ΔT1 = ( 27. 76 ± 8. 90) ms, ΔT2 = (0. 317± 0. 013 ) s; compared with the normal conditions, all three intervention conditions showed significant difference ( P < 0. 01 ) , indicating statistical significance. Conclusion The method of real-time synchronous recording of phrenic nerve discharge, diaphragm discharge and respiratory movement in rabbits was successfully established, and the calculation method for ΔT was determined, which is beneficial for students’ better understanding of the regulatory role of the respiratory center in respiratory movements. Objective This study aimed to improve the experimental setup for investigating factors influencing respiratory motor regulation. The objective was to achieve real-time synchronous recording of phrenic nerve discharge, diaphragmatic muscle discharge, and respiratory movement in rabbits, and to calculate the time difference between phrenic nerve discharge and diaphragmatic muscle discharge (ΔT1) , as well as the time difference between diaphragmatic muscle discharge and the start of the respiratory curve ( ΔT2 ) . Method The phrenic nerve and diaphragmatic muscle of rabbits were isolated, and tracheal intubation was performed. The BL-420I information-integrated signal acquisition and processing system was used to simultaneously record the curves of phrenic nerve discharge, diaphragmatic muscle discharge, and respiratory movements under normal physiological state and different interventions ( increasing the null lumen, increasing the concentration of CO2 , intravenous injection of lactic acid solution at the ear margin, cutting the vagus nerve and stimulating the vagus nerve at the central end) . ΔT1 and ΔT2 were calculated, and 30 respiratory cycles were statistically analyzed. Result The synchronization curves of phrenic nerve discharge, diaphragmatic discharge and respiratory movement were recorded simultaneously under normal physiological state and various intervention conditions by applying BL-420I. Under normal physiological state, ΔT1 = ( 32. 95±5. 34) ms, ΔT2 = ( 0. 366±0. 028) s; after increasing the null lumen, ΔT1 = (28. 63±5. 72)ms, ΔT2 = (0. 295±0. 020) s; after inhalation of CO2 , ΔT1 = ( 20. 72 ± 5. 51) ms,ΔT2 = ( 0. 250 ± 0. 016 ) s; After intravenous injection of lactate, the ΔT1 = ( 27. 76 ± 8. 90) ms, ΔT2 = (0. 317± 0. 013 ) s; compared with the normal conditions, all three intervention conditions showed significant difference ( P < 0. 01 ) , indicating statistical significance. Conclusion The method of real-time synchronous recording of phrenic nerve discharge, diaphragm discharge and respiratory movement in rabbits was successfully established, and the calculation method for ΔT was determined, which is beneficial for students’ better understanding of the regulatory role of the respiratory center in respiratory movements. 

Key words: respiratory movements, phrenic nerve discharge, diaphragm discharge, synchronized recording

摘要： 目的 对呼吸运动调节影响因素实验进行改进,实现家兔膈神经放电、膈肌放电和呼吸运动的实时同步记 录,计算出膈神经放电和膈肌放电的时间差 ΔT1、膈肌放电和呼吸曲线开始的时间差 ΔT2。 方法 分离家兔膈神 经、膈肌,进行气管插管,应用 BL-420I 信息化集成化信号采集与处理系统,同时记录正常生理状态下和不同因素干 预(增加无效腔、增加 CO2 浓度、耳缘静脉注射乳酸溶液、剪断迷走神经、刺激迷走神经中枢端)家兔膈神经放电、膈肌放电和呼吸运动的曲线,并计算出 ΔT1、ΔT2,累计统计 30 个呼吸周期,进行统计学分析。 结果 应用 BL-420I 同 时记录正常生理状态下及各种干预条件下膈神经放电、膈肌放电和呼吸运动的同步曲线。 正常生理状态下,ΔT1 = (32. 95±5. 34) ms、ΔT2 = (0. 366±0. 028) s;增加无效腔后,ΔT1 = (28. 63±5. 72) ms、ΔT2 = ( 0. 295±0. 020) s;吸入 CO2 后,ΔT1 = ( 20. 72 ± 5. 51) ms、ΔT2 = ( 0. 250 ± 0. 016) s;耳 缘 静 脉 注 射 乳 酸 溶 液 后,ΔT1 = ( 27. 76 ± 8. 90) ms、ΔT2 = (0. 317±0. 013) s;三种干预条件与正常生理状态相比,差异均具有统计学意义( P<0. 01) 。 结论 成功构建家兔膈 神经放电、膈肌放电和呼吸运动的实时同步记录方法,并确定了 ΔT 的计算方法,有利于学生更好的理解呼吸中枢 对呼吸运动的调节作用。 

关键词: 呼吸运动, 膈神经放电, 膈肌放电, 同步记录