Salivary amylase activity of rats fed a low calcium diet.

Wistar strain rats fed low calcium diets (1, 2, 3, 4, 6 and 8 weeks) exhibited changes in secretory function of whole saliva. In particular, there were changes in salivary flow rate, total salivary protein, amylase enzyme activity, salivary amylase content and the level of cyclic AMP in the parotid gland acinar cell. Although there were no changes for the first 3 weeks, the levels increased at week 4 and decreased at week 6. The wet weight of the parotid gland started to decrease at week 4. These results suggest that when fed low calcium diets for long periods of time, rats develop defective salivary secretion.