Potassium movement across serosal and mucosal surfaces of frog gastric mucosa

¹ Department of Physiology, The University of Michigan, Ann Arbor, Michigan

Frog gastric mucosa was formed into a sac, filled with 1 ml salt solution and incubated in a large volume of identical salt solution containing 3 mm potassium and K⁴². Total potassium and specific activities of tissue and fluid were measured at 5, 10, 20, 40, 80, and 160 min after start of incubation. The measurements were repeated on mucosas formed into sacs with the mucosal side out. Both types of sacs were also incubated in solutions containing 0.1 mm histamine. Results confirm observations of others that there is net movement of potassium from fluid bathing the serosal surface into the tissue and mucosal fluid and that histamine stimulates potassium movement from tissue into mucosal fluid. The data were used to calculate the ratio of the rate of movement of potassium across the serosal and mucosal surfaces, R_s/R_m. The numerical value of 4.72 was obtained without histamine and 7.16 with histamine.

Key Words: tissue potassium • K⁴² • histamine on potassium movement • tissue barriers to potassium movement

Submitted on May 4, 1964