THE RELATION BETWEEN SALIVARY IODIDE EXCRETION AND THE PLASMA INORGANIC IODINE CONCENTRATION

Abstract

Plasma inorganic iodine, the salivary iodide clearance and the absolute quantity of iodide excreted in saliva were measured in thirty‐eight subjects, none of whom were receiving iodide supplements. The parotid salivary iodide clearance (mean 5.7±0.50 ml./min.), was greater than the submandibular iodide clearance (mean 3.4±0.50 ml./min.). The absolute amount of iodide excreted in saliva was proportional to the plasma inorganic iodine concentration (PII). No relation was found between the PII and the parotid and submandibular salivary iodide clearance. In the thyroid a homeostatic mechanism exists to control the iodine concentrating mechanism. There is no similar mechanism in the salivary glands to control iodine concentration in the saliva, at least within the physiological range. © 1966 The Physiological Society