Unlike other Merkel cell types, the morphology and functions of the Merkel-like basal cells remain
unclear. The aim of the present study was to investigate the ultrastructural features of Merkel-like basal
cells in the nasal septal island (NSI) of dromedaries (Camelus dromedarius) using transmission electron
microscopy and to speculate their potential functions. Ten pairs of nasal septal islands obtained from
ten heads of dromedary camels were used for the current study. Interestingly, these cells have been identified in the basal layer of the neuroepithelium of the dromedary nasal septal island near the sensory
nerve endings. These cells were ovoid to elliptical in shape and rested on the basal lamina. Their surface
had spine like cytoplasmic processes which interwined with the adjacent basal cells. Their nuclei were
large lobulated with 2–3 deep notches. Moreover, numerous dense-core granules surrounded by
electron-lucent halo were aggregated in the basal portion of the cells close to the nerve ending as well
as melanin pigments in the apical portion. The ultrastructural characteristics of the Merkel-like basal
cells of NSI were typical to those of Merkel cells, but with some morphological differences, including their
location, cellular attachments, and connections to other structures. The potential functions were discussed in the light of the cellular context and architecture. The Merkel-like basal cells of the NSI neuroepithelium might play a role in nociception and magnetoreception in dromedaries |
