FACTORS INFLUENCING THE ABSORPTION OF WATER AND CHLORIDES FROM THE INTESTINE

Abstract

The experiments were performed on dogs under the nearest physiological conditions, using colostomies for the study of absorption from the colon, and Thiry Vella loops for the small intestine; also, the amounts of water and chloride secreted by the small intestine were determined and accounted for in determining the absolute amounts of water and chloride actually absorbed. The percentage of chloride and of fluid recovered from a loop of intestine equals that of the fluid introduced at concentrations of 0.5-0.6% for the colon, and 0.6-0.7% for the small intestine. The greatest percentage absorption by the small intestine of both water and chloride, and the greatest absolute absorption of water, is from a solution of about 0.5 percent. The absolute amount of salt absorbed by the small intestine increases with increasing concentrations of salt in introduced fluid up to a concentration of 0.7%. There is no significant increase of salt absorbed above this concentration, until the strongly hypertonic solutions are reached. The percentage of chloride in the absorbed fluid is the same as that in the fluid introduced up to a concentration of 1.2%. More chloride and water are absorbed from solutions containing excess of K ions and considerably more with excess of Ca ions than from 0.9% NaCl or Ringer''s solution. Accacia solution (6%) does not affect the rate of water or chloride absorption, whereas atropine causes increased absorption of both.