Ganglionic neurons in vagal and laryngeal nerves projecting to larynx, and their peptidergic features in the cat.

The distribution of cell clusters in the cervical vagal nerve (CVN), superior laryngeal nerve (SLN) and recurrent laryngeal nerve (RLN), and the peptidergic features of their ganglionic neurons projecting to the larynx, were investigated in the cat using a combination of retrograde tracing by wheat germ agglutinin (WGA) and immunocytochemistry. In the CVN, a few medium sized cell clusters at a level caudal to the nodose ganglion, and some small cell clusters along the course of the vagus, were found. In the SLN and RLN, some medium sized ganglia were located close to the laryngeal framework and a few small groups of cells occupied more rostral parts. Some neurons of the cell clusters in the CVN and most of the ganglionic cells in the SLN and RLN exhibited WGA-immunoreactive (IR) cells, which projected to the larynx. In these WGA-positive ganglionic neurons, many cells showed vasoactive intestinal polypeptide-IR neurons, some neuropeptide Y-IR, and a few substance P-IR and calcitonin gene-related peptide-IR cells were also identified. The present findings indicate that neurons of the cell clusters in the laryngeal nerves, particularly those in the vicinity of the laryngeal framework, project to the larynx and may be autonomic.

Pubmed ID: 7504864 RIS Download