Effect of hypercalcemia on salivary secretion in the dog

¹ Department of Physiology, School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania

An attempt was made to ascertain the effects of an elevated serum calcium level on the rate of secretion and on the movement of sodium, potassium, chloride, bicarbonate, and calcium ions across gland cell membranes in the parotid and mixed glands of three chronic fistulous dogs. Pilocarpine HCl (.36 mg/kg) was injected intravenously to prime secretion and 45 min after the injection of pilocarpine, in the experimental studies, 5–10 ml of calcium gluconate was injected intravenously. Saliva was collected at 15-min intervals for 45 min after the calcium gluconate injection. An increase in the volume secreted, outputs, and concentrations of the ions were noted for the mixed glands during the first 15-min postcalcium injection. During the second 15-min postcalcium, the volumes secreted were significantly below control levels for both the parotid and the mixed gland preparations. Calcium output during the second 15-min postcalcium was decreased in comparison to control values for the parotid glands.