Descending input from the pneumotaxic system to the lateral respiratory nucleus of the medulla. An anatomical study with the horseradish peroxidase technique

Abstract

Horseradish peroxidase (HRP) was injected stereotaxically with control recordings in the lateral respiratory nucleus (nucleus ambiguus (AMB) and nucleus retroambigualis) of the cat. The enzyme was transported retrogradely to neurons of the pons, located mainly in the ipsilateral pneumotaxic system (nucleus parabrachialis medialis (NPBM), Kölliker-Fuse nucleus (KF)). The functional importance of this projection is discussed with regard to a possible control by the pontine network on bulbar respiratory network.