Abstract

(1) Inhibitory responses to field stimulation have been determined in strip preparations from the thoracic, middle and cervical regions of the trachea and in the tracheal tube preparation. (2) The adrenergic neurone blocking drug guanethidine was found to cause a partial reduction of the amplitudes of the responses in all preparations. (3) The guanethidine-resistant inhibitory responses were resistant to pentolinium but were abolished by tetrodotoxin. The data favours the existence of non-adrenergic inhibitory intramural nerves in the guinea-pig trachea. (4) Inhibitory responses have been determined in the presence and absence of guanethidine at frequencies ranging from 2 to 60 Hz. This has enabled the combined responses to stimulation of both adrenergic and non-adrenergic nerves to be compared with the response to stimulation of non-adrenergic nerves alone at each frequency and in each preparation. (5) The contribution of each innervation to the combined inhibitory response was frequency dependent. The adrenergic innervation was more effective at lower frequencies and the non-adrenaration is discussed. Its origin is considered.

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 call

Disclaimer: 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.