兔脑桥中央灰质电刺激和微量注射利多卡因对膈神经放电活动的影响

观察到电刺激兔脑桥中央灰质(CG)对膈神经放电的效应为:吸气相刺激主要引起吸气切断,随后的呼气相缩短;呼气相刺激主要引起呼气相缩短,随后的吸气相提前发生。CG内微量注射利多卡因对膈神经自发放电活动无影响,但使电刺激效应发生可逆性阻断。结果表明:CG参与呼吸活动的调制,但对膈神经放电活动似无紧张性影响。

EFFECTS OF PONTINE CENTRAL GRAY ELECTRIC STIMULATION AND LIDOCAINE MICROINJECTION ON PHRENIC DISCHARGE

Experiments were conducted on 25 rab-bits vagotomized and gal1amine triethiodide-immobillzed. Effects of electric stimulation,electrolytic lesion and lidocaine microinjec-tion of pontine central gray (CG) on phrenicnerve dischage were observed. Thirty-threepoints in CG were stimulated and 294 timesof electric stimulus were performed. Whenthe stimulus was delivered during theinspiratory phase, the main result was aninspiratory off-switch and shortening of theexpiratory phase. When the stimulus wasdelivered during the expiratory phase, thestimulation of the CG mainly resulted inshortening of the expiratory phase and apremature onset of the next inspiratoryphase. After the effective points in CG weredamaged by electrolytic lesion, the samestimulus could no longer induce the effectsmentioned above. Lidocaine micro injectioninto CG could not influence the spontaneousdischarge of the phrenic nerve, but it couldreversely block the effects of the electricstimulation of CG. These experimentssuggest that pontine CG possibly takes partin the modulation of respiration, but itseems to have no tonic effect on thephrenic discharge.