Innervation of Rabbit Intrapulmonary Neuroepithelial Bodies. Quantitative and Qualitative Ultrastructural Study After Vagotomy

The purpose of this study was to locate the cell bodies of origin of the intracorpuscular nerve endings of the intrapulmonary neuroepithelial bodies (NEB). Left infra- or supranodosal vagotomy was performed on 35 young rabbits. In control animals, the NEB innervation index (i.e. the ratio of the number of intracorpuscular nerve endings to the number of NEB corpuscular epithelial cells) was 0.3 in both left and right lungs. Left infranodosal vagotomy decreased the NEB innervation index in the left lung to 0.1 by 24 h postoperatively. Degenerating nerve endings displaying neurofilamentous hyperplasia, were found among the few surviving nerve endings. Left supranodosal vagotomy did not influence the innervation of the NEB of the left lung, even at 5 days postoperatively. In the right lungs, neither procedure had significant effects. These findings indicate that the NEB are predominantly innervated by sensory nerve fibers, derived from cell bodies in the nodose ganglion of the vagus nerve. This neuroanatomical argument corroborates our hypothesis that NEB represent intrapulmonary neuroreceptors.