EFFECTS OF ESSENTIAL PHOSPHOLIPIDS ON THE AMINO-ACID-METABOLISM IN WHOLE-BODY IRRADIATED RATS

Ionizing radiation induces injury to cell membranes resulting in an in crease of plasma amino acids concentration and catabolic response of t he body. Essential phospholipids (EPL) administered before radiation p rotect the cell structures and can be used for their renewal. For this reason EPL are expected to have some effect on amino acid metabolism in radiation sickness. The adult male Wistar rats were injected with E PL in a dose of 125 mg EPL/kg b.w. (Essentiale(R)) or saline solution. Three h later whole-body gamma irradiation with a single dose of 10 G y was performed. Untreated pair-fed rats served as control. The rats w ere sacrificed 2 days after irradiation. In irradiated rats as decreas e in body weight, increased concentrations of plasma amino acids, high er oxidation of branched chain keto acids in liver mitochondria, highe r incorporation of leucine into liver proteins and decreased leucine i ncorporation into proteins of small intestine were observed. In EPL pr etreated rats a longer survival time, a higher body weight, lower leve ls of plasma amino acids and higher protein synthesis in small intesti ne and in liver when compared with irradiated, saline treated rats wer e found. No significant changes were observed in branched chain amino acid oxidation measured by means of labeled ketoisocaproate in liver m itochondria.