Irradiation of rabbit submandibular glands. Histology and morphometry after 15 Gy

Irradiation of rabbit submandibular glands with a single absorbed dose of 15 Gy caused tissue damage which persisted 4 and 10 months later. The injuries were studied by histology, measurement of gland weights and histomorphometry. Reduction of gland weight due to hypoplasia and missed weight gain were seen and the proportions of the three major intralobular compartments of the glands were altered being dependent on the interval between radiation exposure and observation time. The size of the lobules was reduced and extralobular fibrosis in the hilar region increased. The seromucous acini were partly atrophied, with successively changed architecture and reduced size of the granules. The serous tubules showed pronounced reduction of the granules at 4 months and a remarkable adenomatous regeneration at 10 months post irradiation. The striated ducts were almost unaffected during the observation time. Arteriolar changes were slight to moderate, and there was scarcely any capillary damage. The numbers of intra- and extralobular plasma cells were increased.