Composition of Human Saliva, Parotid Gland Secretory Rate, and Electrolyte Concentration in Mentally Subnormal Persons

The parotid gland secretory rate and the electrolyte concentration were determined in twenty-eight Mongoloid and thirty-two non-Mongoloid mentally subnormal persons. Parotid saliva was collected using a metal parotid cup. Citric acid (2.0 per cent) was applied to the tongue at a constant rate of four swabs per minute. Analysis of the fluid obtained revealed a significant rise in pH and concentration of sodium, calcium, and bicarbonate in the Mongoloid group. 634 The secretion rates, potassium, chloride, and phosphorus levels for the two groups were not statistically different. The results of this investigation suggest that an alteration exists in the metabolism of the parotid glands in Mongolism. The precise relationship of salivary gland physiology and the low caries incidence in Mongolism requires additional investigation.