Radiation Effects on Mouse Submandibular Gland

¹ Loyola University School of Dentistry, Chicago College of Dental Surgery, Chicago, Illinois

Twenty-four, 100-day-old, male, CAF-1 mice were used in this study. The normal morphology of the submandibular glands of 12 mice, those used as littermate controls, was studied histologically using hematoxylin and eosin and the periodic acid-Schiff method to stain mucopolysaccharides, the Brachet method for ribonucleic acid, the Feulgen method to localize nuclear desoxyribonucleic acid, DDD for alcohol-insoluble sulfhydryl groups, and silver-impregnation and Mallory trichrome stain to define collagen fibers.

Six mice were irradiated for a total of 100 days with 12 roentgens of gamma radiation daily for a total accumulative dose of 1,200 roentgens. This represented daily radiation for one-half the life-span of these mice. Six additional mice were irradiated for 200 days with the same dosage for a total accumulative dose of 2,400 roentgens. This was two-thirds of the life-span of this group of mice. The purpose was to investigate the effects of chronic, low-grade gamma radiation of the submandibular glands.

The histology of the submandibular gland of the male mouse was similar in many respects to that described in other rodents.

There was additional evidence that radiation of biologic systems was accumulative.

No histopathologic or histochemical changes were observed in the submandibular glands following 12 roentgens of daily gamma radiation for a period of 100 days.

Moderate-to-severe histopathologic and histochemical alterations were seen after 200 days of gamma radiation at the rate of 12 roentgens per day. The mouse submandibular gland showed functional changes, namely, a reduction in numbers and chemistry of the secretary granules. The structural alterations were characterized as degenerative and necrotic changes of both the intralobular-duct cells and the acini.