慢性阻塞性肺疾病对大鼠膈神经放电和呼吸运动的影响

Effects of chronic obstructive pulmonary disease on the discharges of phrenic nerve and the respiratory motion in rats

目的观察慢性阻塞性肺疾病(COPD)对大鼠膈神经放电和呼吸运动的影响。方法20只W istar大鼠随机均分为对照组和模型组。模型组大鼠采用熏香烟加气管内注入内毒素法复制大鼠COPD模型。分别记录对照组和模型组大鼠膈神经放电及呼吸曲线。测量膈神经放电持续时间、间期、放电幅度,测量吸气相时间、呼气相时间、呼吸频率和幅度。结果模型组与对照组比较,膈神经放电幅度增大,差异具有显著性(P=0.005 7),放电持续时间和间期延长,但差异无显著性;吸气相时间和呼气相时间延长,呼吸幅度增加,呼吸频率减慢,但差异均无显著性;对照组和模型组膈神经放电活动与吸气相均呈正相关(r=0.881及r=0.866;均P<0.05)。结论大鼠COPD发生时膈神经放电活动加强,提示呼吸中枢活动发生改变,呼吸中枢吸气驱动增高。

Objective To observe the effects of chronic obstructive pulmonary disease（COPD） on the discharges of phrenic nerve and the respiratory motion in rats. Methods Twenty Wistar rats were randomly and averagely divided into 2 groups, control group and model group. The chronic obstructive pulmonary disease model was established by passive cigarette smoking plus intratracheal instillation of lipopolysaccharide. The discharges of phrenic nerve and the curve of respiration were recorded. The continual time and pausal time, the area and amplitude of discharges of the phrenic nerve were measured. The inspiratory and expiratory time, the amplitude and frequency of respiration were also measured. Results The amplitude of discharges of the phrenic nerve in model group was significantly increased than that in control group（P= 0. 0057）. The continual time and pausal time of discharges of the phrenic nerve in model group were increased, but the differences were not significant compared with the control group （P〉0. 05）. The inspiratory and expiratory time, the amplitude and frequency of respiration in model group were increased, but the differences were not significant compared with the control group （P〉0. 05）. In both the control and model groups, the discharges of the phrenic nerve were positively related to inspiration（r= 0. 881,r= 0. 866~P〈0. 01）. Conclusion In CPOD rats, the discharge of phrenic nerve strengthens, suggesting that the activity of respiratory center has changed and the inspiratory drive increases.