Evidence for a novel neuronal projection from the esophagus to the airways in guinea pigs

Abstract

The aim of the study was to characterize calretinin expressing nerve fibers found to be associated with tracheal parasympathetic ganglia in guinea pigs. Retrograde tracing from the trachea with cholera toxin B identified parasympathetic preganglionic neurons in the nucleus ambiguus and dorsal motor nucleus of the vagus nerve, sensory neurons in the nodose, jugular and dorsal root ganglia, and sympathetic postganglionic neurons in the superior cervical and stellate ganglia. Although some calretinin‐expressing neurons were identified in each of these locations, neurons specifically traced from the airways never expressed calretinin. Calretinin‐immunoreactive nerve fibers disappeared from trach..