Abstract
An investigation was carried out in anesthetized cats to ascertain whether self-excitation of phrenic motoneurons is a specific or generalized reflex mechanism for motoneurons allied to respiration. Whereas stimulation of only caudal intercostal nerves evoked discharge of phrenic motoneurons (intercostal-to-phrenic reflex), stimulation of all intercostal nerves elicited discharges in the recurrent laryngeal nerve (intercostal-to-recurrent laryngeal reflex). Weak superior laryngeal nerve stimulation provoked short-latency discharges in the recurrent laryngeal nerve but inhibited on-going inspiratory activity in phrenic and external intercostal motoneurons. In the presence of self-excitation of phrenic motoneurons (phrenophrenic system), there was concomitant excitation of laryngeal motoneurons. In contrast, when self-excitation of laryngeal motoneurons occurred (laryngolaryngeal system) there was concomitant inhibition of inspiratory activity (phrenic and external intercostal motoneurons). Paired shocks delivered to superior laryngeal and intercostal nerves while recording from phrenic, recurrent laryngeal, and intercostal nerves failed to reveal convergent interaction. It is concluded that self-excitation is a generalized reflex mechanism for certain motoneurons allied to respiration.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
