Accession Number : AD0427201


Title :   METABOLIC STUDIES OF AN AMINO ACID IMBALANCE IN COLD EXPOSED RATS,


Corporate Author : ARCTIC AEROMEDICAL LAB FORT WAINWRIGHT ALASKA


Personal Author(s) : Klain,G J ; Winders,R L


Report Date : Aug 1963


Pagination or Media Count : 11


Abstract : Young rats fed an amino acid-imbalanced diet based on 6% fibrin, and supplemented with 0.4% DL-methionine and 0.6% DL-phenylalanine had increased activities of liver arginine synthetase and arginase, and increased plasma levels of a number of amino acids. However, the activities and levels of these metabolites were decreased in a comparable group of animals exposed to 7 C. The activity of the expired CO2, originating from intraperitoneally administered 2 microcuries each of carbon labeled methionine, phenylalanine or alanine, indicated that the rats kept at room temperature could not effectively oxidize the two imbalancing amino acids to maintain a proper balance in the amino acid pool for the protein synthesis. In contrast, the cold-exposed animals were able to catabolize the excessive levels of methionine and phenylalanine and utilize them for energy purposes. The remaining balanced portion of the amino acid pool was then apparently used for the formation of new tissues, as also indicated by greater gains in body weight. In another experiment it was shown that proteindepleted rats exposed to 3 C for 27 hours readily consumed the imbalanced diet, while the food intake of a comparable group of rats kept at 25 C fell off sharply 18 hours after the animals had been given the diets. (Author)


Descriptors :   DIET , CARBON DIOXIDE , RATS , BIOSYNTHESIS , BODY WEIGHT , TEMPERATURE


Distribution Statement : APPROVED FOR PUBLIC RELEASE