Distinct Organization of Upper Airway Nodose and Jugular Vagal Circuits in the Brain: Evidence from Conditional Anterograde Transneuronal Tracing and Physiology

Abstract

Irritations of the airways evoke brainstem‐mediated reflex changes in breathing and complex sensorimotor responses dependent upon ascending inputs to higher brain centers. Airway vagal afferents terminate in the nucleus of the solitary tract (Sol) and the paratrigeminal nucleus (Pa5) however, whether these nuclei are comparable in terms of afferent inputs, central ascending projections or physiological function is unknown. In Sprague‐Dawley rats (n=4) retrograde tracing with fluorescently tagged cholera toxin B revealed neurons in the jugular vagal ganglia project predominately to the Pa5, while nodose vagal ganglia neurons terminate in the Sol. Electrical stimulation of the trachea in ureth..