THE SECRETION OF IODIDE IN SALIVA

Iodide accumulation by the dog parotid gland continues during rest as well as during secretion. On stimulation of the gland this iodide appears as a brief transient iodide concentration that merges into a lower steady level. The amount of iodide accumulated depends on the duration of the rest period and reaches a limiting value with a half time of ~ 10 minutes. Both transient and steady state saliva/plasma concentration ratios are readily reduced by increased plasma I′ and by CIO 4 ′. The residual iodide secretion after depression by CIO 4 ′ behaves like iodide secretion by the submaxillary gland. This gland has no iodide concentrating system. Iodide clearance values are high and of the order of the estimated total blood flow. Evidence is presented that iodide is concentrated by the duct system and that the ducts have a very high blood flow.