ALTERED BRAIN AND MUSCLE AMINO-ACID LEVELS DUE TO REMOTE INJURY DURING GLUTAMINE SUPPLEMENTATION

Glutamine (GLN) has aroused considerable interest among clinicians and nutritionists after studies demonstrated conclusively profound GLN de pletion during critical illness. Although the brain plays an important role in GLN metabolism, little is known concerning changes in cerebra l handling of GLN following injury. We have evaluated in a rat trauma (bilateral femur fractures) model, the nutritional efficacy of GLN-ric h diet and the remote injury-induced changes in amino-acid (AA) conten ts of brain and muscle tissues. Both control and traumatised rats were starved for 2 days and then pair-fed for 4 days, either a basic liqui d diet (BioServ # F1259) or an isonitrogenous test diet which containe d the same basic diet from which 10% nitrogen (N) was replaced by GLN- N. Protein efficiency ratio as well as plasma levels of anabolic growt h hormone and insulin did not change due to GLN-enriched diet. Remote injury-induced changes in GLN and glutamic acid (GLU) during GLN-rich diet were minimal in brain tissues; whereas GLN levels were decreased in plasma and muscle, GLU levels were increased in plasma and decrease d in muscle tissues. The AA levels of brain tissues, in general, were maintained within narrow limits during GLN supplementation in control and injured rats. An increased influx of tryptophan and increased synt hesis of the neurotransmitter serotonin were suggested due to GLN-enri ched diet.