Morphology of the intralobular duct of the submandibular gland in rats in case of experimental diabetes mellitus

The objective of study is to study the peculiarities of morphological changes in different subdivisions of the intralobular duct of the submandibular gland (SMG) in rats in case of experimental diabetes mellitus (DM). The study included sexually mature male Wistar rats. Experimental DM was induced by streptozotocin. Electron microscopic study of subdivisions of the intralobular duct of the SMG was carried out on the 14th, 28th, 42nd, 56th, and 70th days of the experiment. In early stages of experimental DM the intercalated ducts are characterized by a relatively unchanged structure, and in late stages vacuolization of the cytoplasm of their epithelial cells is observed. Since the 14th day vacuolization of mitochondria is observed in epithelial cells of the granular ducts being the most pronounced on the 28th day and not apparent over the subsequent periods. The degree of filling with granules reduces till 56th day, however, it increases sligthly on the last day of the experiment. On the 28th–70th days vacuolization of the cytoplasm is observed in epithelial cells of the striated ducts. In addition, on the 14th day the mitochondrial matrix of these cells condenses; over the next periods it becomes enlightened and mitochondrial cristae are clearly visualized and disorganized. Conclusion: In the intralobular duct of the SMG in experimental DM dystrophic changes of different intensity occur in the granular and striated ducts on the 14th day and in the intercalated ducts only since the 42nd day of the experiment.