Morphological differences between regenerating salivary glands after salivary gland duct ligation and embryonic salivary glands

Most animals and organs have regenerative capabilities. Whether regeneration is a developmental process or a distinct phenomenon that is independent of development is debatable. We examined the differences between developing and regenerating salivary glands using duct-ligation models. We performed morphological analyses comparing submandibular gland regeneration and development. To reveal the proliferation processes that occur during salivary gland regeneration and development, we counted the number of Ki67-positive cells over time. In addition, we examined the expression of the following markers: aquaporin 5, smooth muscle actin, cytokeratin 7, and tubulin beta 3. The proliferation patterns seen during regeneration differed from those observed during development. Different salivary gland marker expression patterns were seen during development and regeneration. This study showed that regenerating salivary glands do not follow the same growth process as developing salivary glands.