谷氨酰胺对铜绿假单胞菌所致肺部感染大鼠的防护作用

目的探讨谷氨酰胺在全胃肠外营养（TPN）中对铜绿假单胞菌所致肺部感染大鼠的保护作用。方法SD大鼠40只,随机分为4组,A组大鼠向气管内注入生理盐水0．3ml。B组大鼠向气管内注入0．3ml的铜绿假单胞菌悬浮液,并使细菌直接进入肺内。C组大鼠静脉泵标准的不含N（2）L-丙氨酰-谷氨酰胺（商品名为力肽）的TPN溶液160ml／kg,5d;D组大鼠静脉泵含力肽的TPN溶液160ml／kg,5d;C、D组大鼠第6天向气管内注入0．3ml的铜绿假单胞菌悬浮液,并使细菌直接进入肺内。观察大鼠生命活动。注菌48h后取外周血计数白细胞;行支气管肺泡灌洗,取灌洗液,计数其中的白细胞,测其中的TNFα、IL-1、IL-10水平及总蛋白含量。取肺、肝、回肠小块组织,光镜下观察病理改变。结果（1）实验开始时4组大鼠体重无明显差别,第8天时B、C、D组大鼠体重较A组轻;C组死亡的鼠数多于D、B组。（2）C组大鼠外周血WBC计数、血清中TNFα、IL-1高于D组,而IL-10低于D组。C组大鼠支气管肺泡灌洗液中WBC计数、总蛋白含量、TNFα高于D组,而IL-10低于D组。（3）光镜下见C组大鼠肺、肝、回肠组织病理改变明显重于D、B组,A组基本正常。结论谷氨酰胺可保护TPN大鼠的胃肠道功能,提高肺部抗感染能力,并减轻由严重感染所致其他重要器官的损害。

Protective effect of glutamine on rats with pseudomonas pneumonia

OBJECTIVE: To investigate the protective effect of glutamine in rats with pseudomonas pneumonia receiving total parenteral nutritional (TPN) therapy. METHODS: Forty Sprague-Dawley rats were randomly divided into 4 groups (Group A, B, C and D). Rats in Group A received, by intra-tracheal route, infusion of 0.3 ml normal saline. Rats in Group B received, also by intra-tracheal route, infusion of 0.3 ml pseudomonas aeruginosa soliquoid so that the bacteria entered the lungs directly. A standard TPN solution not containing glutamine was administered intravenously to rats in Group C (160 ml/kg) for 5 days, and a TPN solution containing glutamine was administered intravenously to rats in Group D (160 ml/kg) for 5 days. On day 6, 0.3 ml pseudomonas aeruginosa soliquoid was administered by intra-tracheal route to rats in Group C and D. The weight of rats, their activity and mortality were recorded. 48 h after intratracheal administration, blood and bronchoalveolar lavage fluid (BALF) samples were collected for measurement of white blood cell count, TNFalpha, IL-1, IL-10 and total protein of BALF. Segments of the lung, the liver and the ileum tissues were collected for HE pathological slice. RESULTS: (1) Initially there was no difference in weight between the four groups, but on day 8 the weights of rats in Group B, C, and D were significantly decreased compared with that in Group A (P < 0.05). The mortality of rats in Group C was significantly higher than that in Group B and D (P < 0.05). (2) There were significant differences between Group C and D in white blood cell count, blood TNFalpha and IL-10 level, BALF, and total protein of BALF (P < 0.05). (3) Pathological changes of the lung, the liver and ileum in Group C were more severe than that in Group B and D. Group A was basically normal. CONCLUSION: Glutamine is able to protect gastrointestinal tract function in rats receiving TPN, to improve pulmonary anti-infection ability, and to alleviate injuries of important organs caused by severe infection.