Fox A D, Kripke S A, De Paula J, Berman J M, Settle R G, Rombeau J L
Department of Surgery, University of Pennsylvania, Philadelphia 19104.
JPEN J Parenter Enteral Nutr. 1988 Jul-Aug;12(4):325-31. doi: 10.1177/0148607188012004325.
Administration of an elemental diet to rats given methotrexate (MTX), 20 mg/kg intraperitoneally (ip), results in 100% mortality from severe enterocolitis. Previous studies indicate that glutamine (GLN), which is not present in elemental diets, is the preferred oxidative substrate for the gut and may facilitate intestinal recovery after injury. This study investigated the effects of a glutamine-supplemented elemental diet (GLN-ED) on nutritional status, intestinal morphometry, bacterial translocation and survival in this lethal model of intestinal injury. Three experiments were performed. In the first experiment, rats received an intragastric elemental diet supplemented with either 2% GLN or an equivalent amount of glycine (Control). After 4 days animals received either MTX, 20 mg/kg ip, or saline ip and were killed 3 days later. The GLN-ED resulted in significantly decreased weight loss, improved nitrogen retention, and increased mucosal weight, protein, and DNA content of the jejunum and colon. In the second experiment rats were assigned to diet as in the first experiment, but all animals received MTX. Control diet animals died within 120 hrs of MTX administration. The GLN-ED group had significantly longer survival time and decreased mortality. In the third experiment animals were assigned to diet and MTX as in the first experiment. Ninety-six hrs later aortic blood cultures revealed enteric bacteremia in animals administered MTX. GLN-ED resulted in a significant reduction in the incidence of bacteremia. These experiments showed that a GLN-ED significantly improved nutritional status, decreased intestinal injury, decreased bacterial translocation, and resulted in improved survival in a lethal model of enterocolitis.
给腹腔注射20mg/kg甲氨蝶呤（MTX）的大鼠喂食要素饮食，会导致严重小肠结肠炎造成100%的死亡率。先前的研究表明，要素饮食中不存在的谷氨酰胺（GLN）是肠道首选的氧化底物，可能有助于损伤后肠道的恢复。本研究调查了补充谷氨酰胺的要素饮食（GLN-ED）对这种致死性肠损伤模型中营养状况、肠道形态学、细菌移位和存活率的影响。进行了三项实验。在第一个实验中，大鼠接受胃内给予的补充2%GLN或等量甘氨酸的要素饮食（对照）。4天后，动物接受腹腔注射20mg/kg MTX或生理盐水，3天后处死。GLN-ED导致体重减轻显著减少、氮潴留改善，空肠和结肠的黏膜重量、蛋白质和DNA含量增加。在第二个实验中，大鼠的饮食分配与第一个实验相同，但所有动物都接受MTX。对照饮食组动物在给予MTX后120小时内死亡。GLN-ED组的存活时间显著延长，死亡率降低。在第三个实验中，动物的饮食和MTX分配与第一个实验相同。96小时后，主动脉血培养显示接受MTX的动物出现肠源性菌血症。GLN-ED导致菌血症发生率显著降低。这些实验表明，GLN-ED显著改善了营养状况，减轻了肠道损伤，减少了细菌移位，并提高了致死性小肠结肠炎模型的存活率。
