This study was aimed to investigate the effects of glutamate ( Glu) on intestinal energy metabolism in the lipopolysaccharide ( LPS)⁃challenged weaned piglets. Twenty⁃four weaned pigs were assigned to four groups as control group, LPS group, LPS+1.0% Glu group and LPS+2.0% Glu group with 6 replicates each and 1 pig in per replicate. On the 28th day of the trial, the piglets in the experimental groups were injected with 100 μg/kg BW LPS, and the piglets in the control group were injected with the same amount of 0.9% NaCl solution. At 4 h post⁃injection, pigs were slaughtered and intestinal samples were collected for further analysis. The results showed as follows: 1 ) LPS challenge significantly decreased ATP and total adenine nucleotide (TAN) contents and energy charge (P<0.05), but significantly increased the ratio of AMP to ATP (P<0.05) in jejunum compared with the control group; LPS+2.0% Glu group significantly increased the contents of ATP, ADP and TAN ( P<0. 05) in jejunum compared with LPS group. 2) Compared with the control group, LPS challenge had a tendency to decrease the alpha⁃oxoglutarate dehydrogenase complex activity ( P=0.092) in jejunum and extremely significantly decreased the activities of citrate synthase and alpha⁃oxoglutarate dehydrogenase complex ( P<0.01) in ileum; compared with LPS group, Glu had no significant effects on the activities of tricarboxylic acid cycle key enzymes ( P>0.05) in jejunum and ileum, except for the citrate syn⁃thase activity in ileum was significantly reduced in LPS+1.0% Glu group (P<0.05). 3) LPS challenge ex⁃tremely significantly decreased the mRNA expressions of peroxisome proliferator⁃activated receptor gamma co⁃activator⁃1α ( PGC1α) in jejunum and silent information regulator 1 ( Sirt1) and PGC1α in ileum ( P<0.01) compared with the control group;compared with LPS group, LPS+2.0% Glu group had a tendency to increase the mRNA expressions of PGC1α in jejunum ( P=0.067) and Sirt1 in ileum ( P=0.053) , while LPS+1.0%Glu group had a tendency to increase the Sirt1 mRNA expression in ileum ( P=0.070) . These results indicate that dietary supplementation of Glu can improve energy loss status in LPS injured intestine.%本试验旨在研究谷氨酸（ Glu）对脂多糖（ LPS）刺激断奶仔猪肠道能量代谢的影响。选择24头断奶仔猪分为4个组，分别为对照组、LPS组、LPS＋1．0％ Glu组和LPS＋2．0％ Glu组，每组6个重复，每个重复1头猪。于试验第28天，试验组猪注射100μg／kg BW LPS，对照组注射等量的生理盐水，4 h后屠宰，取肠道样品待测。结果表明：1）与对照组相比，LPS刺激导致断奶仔猪空肠三磷酸腺苷（ATP）、腺苷酸池（TAN）含量和能荷（EC）显著降低（P＜0．05），一磷酸腺苷（ AMP）／ATP值显著升高（ P＜0．05）；与LPS组相比，LPS＋2．0％ Glu组显著提高了空肠ATP、二磷酸腺苷（ ADP）和TAN含量（ P＜0．05）。2）与对照组相比，LPS刺激导致断奶仔猪回肠柠檬酸合成酶和α－酮戊二酸脱氢酶系活性极显著降低（ P＜0．01），空肠α－酮戊二酸脱氢酶系活性有降低趋势（ P＝0．092）；与LPS组相比，除LPS＋1．0％ Glu组回肠柠檬酸合成酶活性显著降低（ P＜0．05）外，Glu对空肠和回肠三羧酸循环关键酶活性无显著影响（ P＞0．05）。3）与对照组相比， LPS刺激导致空肠过氧化物酶体增殖物激活受体γ辅激活因子1α（ PGC1α）及回肠沉默信号调控因子1（Sirt1）和PGC1α的mRNA表达量极显著降低（P＜0．01）；与LPS组相比，LPS＋2．0％Glu组有提高空肠PGC1α（P＝0．067）和回肠Sirt1（P＝0．053）mRNA表达量的趋势，LPS＋1．0％Glu组有提高回肠Sirt1 mRNA表达量的趋势（ P＝0．070）。由此可见，Glu可以改善LPS刺激导致的肠道能量损耗状态。
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