Effect of alloxan-diabetes on alpha-amylase and sialic acid levels in the parotid and submandibular glands of rats.

The relationship of diabetes to salivary gland metabolism has been investigated by comparing the levels of alpha-amylase, sialic acid and total protein in the parotid and submandibular glands, plasma and kidneys of control and alloxan-diabetic rats. A significant decrease in alpha-amylase activity was found in both the parotid and submandibular glands of the diabetic rats by use of both a chemical and an electrophoretic assay. Plasma and kidney levels of the enzyme were not altered in the diabetic rats. Sialic acid levels were not affected by the alloxan-induced diabetes. Although the total protein concentration was significantly altered only in the kidneys of the alloxan-diabetic rats, the electrophoretic patterns of both the parotid and submandibular gland soluble proteins were markedly different between the control and alloxan-diabetic rats. The electrophoretic data indicate that protein metabolism in general, and the alpha-amylase concentration specifically, are altered in the salivary glands of alloxan-diabetic rats.