Effect of metabolic acidosis on acinar cells of rat submandibular gland.

Metabolic acidosis of the exocrine glands could be an important factor in the pathogenesis of the disease cystic fibrosis, a generalized exocrinopathy. Acidosis was induced in rats by addition of ammonium chloride to the drinking water. X-ray microanalysis of the mucous acinar cells of the submandibular gland showed increased intracellular calcium concentrations, and an increased intracellular potassium to sodium ratio. Transmission electron microscopy showed a swelling of the cells, and an increase in the relative cellular mucus content. The changes in structure and composition of the submandibular gland cells in the acidotic rat resemble those found in cells from cystic fibrosis patients and in pharmacologically induced animal models of the disease.