Formation of saliva and potassium transport in the perfused cat submandibular gland

Abstract

1. In the cat submandibular gland perfused with modified Locke solutions, salivary secretion during acetylcholine (ACh) infusion and K uptake from the perfusion fluid after the ACh-induced K loss were measured.2. Strophanthin G (10(-5)M) abolished K uptake, whereas salivary secretion was unaffected.3. Ethacrynic acid (10(-4)-2 x 10(-4)M) hardly affected K uptake whereas salivary secretion was severely inhibited.4. During perfusion with Ca-free solution K uptake was unaffected, whereas salivary secretion was severely reduced.5. The presence or absence of CO(2)/HCO(3) in the perfusion fluid was of no importance for the secretory process and the K uptake. Acetazolamide (2 x 10(-4)-10(-3)M) did not inhibit these transport processes.6. It is suggested that two kinds of Na transport occur in the acinar cells of the salivary glands: a Na extrusion coupled with K uptake, responsible for the maintenance of the concentration gradients across the cell membrane; and a Na transport coupled with Cl transport into the acinar lumen, responsible for the formation of the primary secretion.