Intestinal transport of amino acids in protein-deficient rats and the effect of rehabilitation using a casein diet.
The effects of protein deprivation and subsequent rehabilitation on the intestinal absorption of a mixture of amino acids were studied in albino rats. The absolute amounts of amino acids transported across the intestine were greater in rats fed for 28 days 17% casein diet than those fed 3% maize protein or no-protein diets. The absorption per unit intestinal DNA (termed as absorptive capacity) of amino acids, except L-arginine in males, was more in rats fed the 3% maize protein diet than those fed the casein diet. The changes in the absorptive capacity of two sexes, when fed the protein-free diet, were not similar. The males absorbed L-arginine and L-methionine, and females L-histidine and L-tryptophan at rates faster in the protein-free group than their counterparts in the casein group. The differences between protein-free and casein groups in the absorption of L-tryptophan and L-histidine in males and L-arginine and L-methionine in females were not significant. The augmentation in absorptive capacity of intestinal cells in protein-deficient rats was a temporary adaptation to the condition that resulted in reduced intestinal cell population. Rehabilitation of protein-deficient rats for 32 days on the casein diet, resulted in an increase in intestinal cell population, return of absorptive capacity of intestinal cells to normal, and improvement in net absorption rates.
D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D002364:Caseins / Q000008:administration & dosage; D004247:DNA / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D005502:Food; D007408:Intestinal Absorption / Q000187:drug effects; D007421:Intestine, Small / Q000502:physiology*; D008297:Male; D010940:Plant Proteins / Q000008:administration & dosage; D011488:Protein Deficiency / Q000378:metabolism*; D051381:Rats; D012737:Sex Factors
D000596:Amino Acids; D002364:Caseins; D004044:Dietary Proteins; D010940:Plant Proteins; D004247:DNA