Cytoarchitectural differences of myoepithelial cells among goat major salivary glands

Abstract

Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry, and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion, the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance in the diagnosis of atrophy and pathogenic conditions of these glands.

Characterization of the myoepithelial cells in the major salivary glands of the fruit bat Artibeus jamaicensis

“…These results appear to be consistent with the finding that MECs have a greater number of cytoplasmic projections in mucous‐secreting salivary glands as well as in glands with a larger amount of secretory granules (Hata et al. ; Elewa et al., ,b). We also observe that the SMAα, KRT14 and DES transcripts are differentially expressed in the myoepithelial cells.…”

“…The parotid gland of A. jamaicensis is composed of mucous acini and seromucous tubular structures lacking demilunes; therefore, it is a mixed secretory gland. This characteristic makes this gland different from those of other mammals, such as humans, the European hamster (Banan Khojasteh & Delashoub, 2012), porcupine (Banan Khojasteh & Khajehnasiri, 2011), miniature pig (Zhou et al 2010), armadillo (Estecondo et al 1995), and goat, sheep and mouse (Elewa et al 2010b), in which the secretory portions of this gland are serous acini. The submandibular gland of A. jamaicensis was observed to manifest characteristics of a mucous-secreting gland, with mucous demilunes similar to those found in carnivores (Pinkstaff, 1993a).…”

“…), and goat, sheep and mouse (Elewa et al. ), in which the secretory portions of this gland are serous acini.…”

“…Considering that in addition to contraction, the role of myoepithelial cells is to provide support and protection to the parenchyma (Redman, ; Elewa et al. ,b), the locations of the studied proteins could be related to these functions. Desmin was found in a very low quantity in the parotid gland compared with that in the submandibular and sublingual glands.…”

Comparative analysis of mediastinal fat‐associated lymphoid cluster development and lung cellular infiltration in murine autoimmune disease models and the corresponding normal control strains

“…Immunohistochemical procedures were performed according to our previous report. 29 To detect cell proliferation, bromodeoxyuridine (BrdU) -positive cells were observed within the MFALCs and lungs of the strains studied. The detection of BrdU-positive cells was performed according to our previous report.…”