Simultaneous flux of potassium into and out of the dog intestine

Abstract

Potassium moves across the intestinal mucosa from the lumenal surface to the blood simultaneously with a stream in the opposite direction from blood to lumen. The net result of these two flows determines the amount of potassium appearing in the intestinal lumen. These two flows were measured across isolated loops of intestine in the dog with the use of radiopotassium. For a 20-cm length of intestine, potassium enters the lumen at 0.8–6.5 µEq/min., and simultaneously leaves the lumen at 0.7–5.2 µEq/min.