EFFECTS OF POSTOPERATIVE PERIODS ON GLUCOSE-ABSORPTION AND ELECTROLYTE SECRETION IN THE INTESTINAL LOOP OF SHEEP

This study was designed to determine the effect of postoperative perio ds on intestinal absorptive and secretory functions in the jejunal Thi ry-Vella loop of sheep. The lumen was perfused with isotonic saline so lution for 120 min at 1 ml/min. The secretory function was assessed by measuring the secretory response of water and electrolytes to PGE, wh ich was applied intraluminally at 100 mu M during the second 30 min pe riod. To measure glucose absorption, 10 mM isotonic glucose solution w ith its osmolality adjusted by adding NaCl was perfused. Measurements were taken at 1 week intervals for 3 months after surgery. Under basal conditions, water, sodium and chloride were absorbed, while potassium and bicarbonate were secreted. These net basal movements did not chan ge throughout. the 3 month period. PGE, reversed the net absorptions o f water, sodium and chloride to the net secretions, and significantly augmented bicarbonate secretion. Potassium secretion was not changed s ignificantly by PGE,. These responses to PGE(2) were not affected by t he postoperative periods. Glucose absorption decreased gradually for 8 weeks after construction of the jejunal loop with a significant negat ive correlation to the postoperative period, and subsequently remained at a steady state of nearly 65% of the first week. This decrease in g lucose absorption was prevented by regular perfusion of glucose. The r esults show that the Thiry-Vella loop of the ovine jejunum can be used to measure secretory function for 3 months or more after its construc tion, but it is essential to regularly perfuse the loop with glucose s olution when this loop is used for absorptive experiments of glucose f or a long time.