I.Intestinal absorption of an amino-acid mixture in normal subjects

Summary

• 1. Absorption of an enzymatic hydrolysate of casein from the upper jejunum was studied in normal human beings by the Miller-Abbott technique of intestinal intubation.

• 2. In open loops, with the upper jejunum and gastro-intestinal region in continuity, the test mixture at the end of a half hour was always diluted to a nitrogen concentration of 2 rag. per cc. regardless of the amount of nitrogen originally present in the test material. In closed loops, however, this physiological adjustment did not occur with any regularity.

• 3. In open loops, the amount of nitrogen absorbed varied with the amount originally introduced in the 5% to 15% mixtures while the percentage of absorption decreased from 98% to 72%, respectively. In closed loops, however, absorption from 15% mixtures showed very little increase over the 10% group.

• 4. Absorption of substances giving the tyrosine-tryptophane reaction usually paralleled the nitrogen absorption.

• 5. The technique used, while not adaptable to precise interpretation in terms of grams absorbed per hour per unit area, can be kept constant, and lends itself to use in similar studies in pathological states.