Summary: | 碩士 === 臺北醫學大學 === 保健營養學系 === 91 === This study investigated the effects of parenterally infused glutamine (GLN) or arginine (Arg) on hormone secretion, nutrient metabolism and immune response in rats with gastroectomy. Male Wistar rats weighting 230-250 g were used in this study. Experiment 1: rats with internal jugular catheters were assigned to GLN and Control groups. Both groups received isonitrogenous total parenteral nutrition (TPN) with 6.84g nitrogen/L. The calorie density of the TPN solution is 1 kcal/mL, and the ratio of nitrogen/calorie is 1:145. The glutamine group replaced 25% of the total amino acid nitrogen as GLN. After receiving TPN for 3 days, one third of the rats in each experimental group were sacrificed as baseline group, after then the remaining rats underwent partial gastrectomy and were sacrificed 24 and 72 h, respectively, after surgery. Plasma, peritoneal lavage fluid (PLF), organs and urine samples were collected for further analysis. Experiment 2: Rats were assigned to Arg and Control groups. The Arg content in the Arg group replaced 23% of the amino acid nitrogen in TPN solution. The experimental procedure was identical with the experiment 1. The results of experiment 1 showed that compared with Control group, GLN group had lower nitrogen loss at 1st and 2nd d after surgery, also, higher plasma insulin and insulin like growth factor- I concentration at 1st postoperative day were observed. The phagocytic activity of peritoneal macrophage is higher in GLN group than Control group 1 day after surgery. No significant differences of IL-1β, IL-6 levels in plasma, PLF and stimulated splenocyte were observed among the groups at various time schedule. The TNF-α concentration in PLF is higher in Control group than GLN group 3 d after surgery. Experiment 2 showed that there were no significant differences in nitrogen balance and plasma hormone concentrations between the 2 groups at each time point. The IL-1β secreted by splenocyte was higher in the Arg group 1 d after surgery, whereas TNF-α concentration is higher in Control group 3 d after surgery. Malondialdehyde concentration in liver is higher in the Control group than the Arg group 1 d after surgery. These findings suggest that TPN supplemented with GLN enhanced phagocytic activity of peritoneal macrophage. Also, plasma insulin and IGF-I concentration were increased, which may consequently improve nitrogen balance after surgery. We observed that Arg supplementation reduced the secretion of TNF-α in PLF, and the peroxidation products in liver were also decreased. However, Arg administration had no effect on peritoneal macrophage and blood neutrophil phagocytic activity, and the effect of Arg on improving nitrogen balance was not obvious.
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