Pulmonary neuro-epithelial bodies—ultrastructure, surface morphology and effects of pharmaca in vitro

Abstract

Recently, intraepithelial innervated corpuscles, referred to as neuro-epithelial bodies (NEB) have been identified within the airway mucosa of human and animal lungs. The specialized cells of NEB share certain features of APUD (Amine Precursor Uptake and Decarboxylation) endocrine cells, such as argyrophilia, amine contents and presence of cytoplasmic dense core vesicles (DCV). Although the precise function of NEB in lung remains still unknown, it has been suggested that NEB may represent intrapulmonary receptors or alternatively may have an endocrine function.In this study, NEB in lungs of near-term rabbit fetuses (29 days gestation) were examined by transmission (TEM) and scanning electron microscopy (SEM), prior to and following short term organ culture. The ultrastructure and surface morphology of NEB in control animals was compared with a) NEB in rabbit fetal lung explants maintained in vitro for 7-10 days; b) lung explants incubated with reserpine, (an amine releasing agent) or Ca++ ionophore A-23186 (compound used for studies of calcium mediated secretion).