Histology of the Carotid Body

Abstract

The histological study of the carotid bodies of human cadavers was performed using light microscopy and hematoxylin and eosin staining technique. We found good criteria to distinguish the cell types of this structure. The carotid body is a small neurovascular structure situated at the bifurcation of the common carotid artery. It is divided into 6-8 lobules, each of which consists of groups of cells and several sinusoids with large diameters surrounded by a thin capsule with small nerve bundles lying close to it. There are 4 cell types in each group, the glomus type I cell, the glomus type II cell, the ganglion cell and the fibroblast. The glomus type I cell are the principal cells which have oval or round nuclei function. The glomus type II cells have round nuclei with deeply staining and acidophilic cytoplasm indicating that they are in a resting atage. The ganglion cells, either separated or a group of few cells, are situated at the periphery of each group and near the blood sinusoids. The hypothesis that the glomus type I cell and the glomus type endocrine gland and the cells gradually differentiate from a resting into the active stage. Further studies are needed to confirm whether the type I cells are in APUD series and this will be done by only transmission electron microscopy.