Abstract

The inorganic components of submandibular saliva were determined in 35 patients with cystic fibrosis and in 28 controls. No differences due to flow rate were apparent between the two groups. At comparable flow rates, cystic fibrosis submandibular saliva had higher concentrations of calcium, sodium, and chloride, and similar concentrations of magnesium, inorganic phosphate, potassium, copper, and zinc. The insoluble, turbid fraction of the cystic fibrosis submandibular saliva contained both calcium and phosphate, and these were precipitated in a ratio which was consistent with hydroxyapatite. The secretory granules are postulated as the source of the excess calcium in cystic fibrosis submandibular saliva.