Accession Number : AD0710698

Title :   RESEARCH OF THE MECHANISMS AND METABOLISM OF PROTEINS AND RELATED COMPOUNDS,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE DEPT OF NUTRITION AND FOOD SCIENCE

Personal Author(s) : Gray,Seymour J.

Report Date : JUN 1970

Pagination or Media Count : 75

Abstract : When equimolar mixtures of eight essential L-amino acids at varying concentrations (1-20mM) were perfused into the jejunum of man a characteristic sequence of amino acid absorption was constant for each of the amino acids. A characteristic sequence of absorption was also observed following the perfusion of equimolar mixtures of 18 L-amino acids at concentrations of 1-8 mM. With the intestinal perfusion of isonitrogenous amino acid mixtures simulating egg and corn protein, the percentage of each amino acid absorbed was similar for the two food mixtures. The absolute amount of each amino acid absorbed, however, depended upon its molar concentration in the food mixtures and its absorption rate. During a 6-day period of complete starvation the weight loss of the small intestine of albino rats was out of proportion to body weight loss. The intestinal cell population was diminished, and there was a decrease in the RNA protein and water content of the individual cells. In man the uptake of C14-L-valine by the jejunal mucosa obtained by peroral biopsy was greater in the obese than in the normal. The kinetic constants, Km, and Vmax, were increased significantly in the obese. Total tissue water, extracellular water space, tissue nitrogen, and DNA were not altered. (Author)

Descriptors :   (*PROTEINS, *METABOLISM), AMINO ACIDS, ABSORPTION(BIOLOGICAL), FOOD, EGGS, BODY WEIGHT, INTESTINES, TISSUES(BIOLOGY), WATER, CELLS(BIOLOGY), NITROGEN, DEOXYRIBONUCLEIC ACIDS, MICE

Subject Categories : Biochemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE