Influence of Dietary Amino Acids on Pancreatic Enzymes

Abstract

Rats were fed a low casein diet to which was added either single dl-amino acids to make 1% of the diet or supplements of dl essential amino acids equivalent proportionally and in total amount to an extra 8% casein. Glycine was added to substitute for the nonessential acids in casein. In six groups of rats this supplement was lacking in pairs of essential amino acids previously found to stimulate protease and lipase production. The pairs were made up of all possible combinations of the four acids in question. Threonine addition reduced all enzyme activities. Threonine removal increased protease activity. Arginine and histidine additions increased protease and lipase respectively. The complete amino acid supplement reduced protease below the control as did the supplement lacking in methionine and phenylalanine. No activity was increased by any amino acid mixture supplement. Lipase and amylase were unchanged by the mixtures except for an amylase depression in the group receiving a supplement lacking isoleucine and valine.