Related Experiment Videos
Microliths in normal salivary glands of cat investigated by light and electron microscopy
A Triantafyllou1, J D Harrison, J R Garrett
1Department of Oral Pathology, Rayne Institute, King's College School of Medicine and Dentistry, London, UK.
Abstract:
This investigation concerns the natural history of microlith in the salivary glands of cat. Microliths were detected in more sublingual than submandibular glands and were almost absent in the parotid. They were found intraparenchymally, intraluminally and interstitially, and ultrastructurally in phagosomes of acinar, ductal and myoepithelial cells, intermixed with the cytoplasm of degenerate acinar cells, and in intraparenchymal macrophages and a multinuclear giant cell. They appear to form in healthy acinar cells during autophagocytosis, and possibly to be discharged luminally, laterally or basally, and to form in the debris of degenerate cells intraparenchymally and intraluminally. They appear to be removed by expulsion in the saliva, scavenging macrophages, and possible eventual degradation in the parenchymal phagosomes. The greater occurrence of microliths in the sublingual gland may relate to a low level of secretory activity, and the near absence of microliths in the parotid to a low level of calcium. The feline salivary glands were found to be an outstanding model for the investigation of microlithiasis.
Insights
Feline salivary glands are excellent models for studying salivary microliths. These mineral concretions form via autophagocytosis in acinar cells and are cleared through saliva or macrophages.
Area of Science:
- Veterinary Pathology
- Mineral Metabolism
- Cell Biology
Background:
- Salivary microliths, or salivary calculi, are mineralized deposits found within salivary glands.
- Their formation, composition, and clearance mechanisms are not fully understood across all species.
- The feline salivary gland system presents a unique opportunity to study these phenomena.
Purpose of the Study:
- To investigate the natural history and cellular localization of salivary microliths in cats.
- To elucidate the formation and clearance pathways of these mineral concretions.
- To evaluate the feline salivary gland as a model for studying microlithiasis.
Main Methods:
- Histological and ultrastructural examination of feline salivary glands (sublingual, submandibular, parotid).
- Localization of microliths within acinar, ductal, and myoepithelial cells, as well as macrophages.
- Analysis of cellular processes, including autophagocytosis and cell degeneration, in relation to microlith formation.
Main Results:
- Microliths were most prevalent in sublingual glands, less so in submandibular, and rare in parotid glands.
- Ultrastructural analysis revealed microliths within phagosomes, degenerate cells, macrophages, and multinuclear giant cells.
- Formation appears linked to autophagocytosis in healthy acinar cells and degeneration, with clearance via saliva, macrophages, or degradation.
Conclusions:
- Feline salivary glands, particularly the sublingual gland, serve as a valuable model for microlithiasis research.
- Microlith formation involves cellular processes like autophagocytosis and degeneration, with diverse clearance mechanisms.
- Differences in occurrence may relate to gland secretory activity and local calcium levels.