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目的:测定脓毒症大鼠早期血浆代谢组学指标，寻找不同时间点的脓毒症差异代谢物和相关代谢通路，初步揭示脓毒症大鼠早期的病理生理变化。方法:将15只8周龄雄性SD大鼠按随机数字表法分为假手术组（S组，6只）和脓毒症组(C组，9只)，采用盲肠结扎穿孔术制备脓毒症大鼠模型；S组只游离盲肠，不予以结扎和穿孔。造模后2、6、12 h通过眼眶采血收集血浆，利用气相色谱-质谱（gas chromatography-mass spectrometry，GC-MS）联用技术测定血浆代谢组学，利用NIST数据库和Feihn代谢组学数据库的标准离子片段谱库比对鉴定内源性代谢物。通过MetaboAnalyst 4.0网站进行多元回归分析，包括主成分分析（principal components analysis，PCA）和偏最小二乘法判别分析（partial least squares discriminant analysis，PLS-DA）模式识别各代谢物的变化，筛选相关差异代谢物[n P1.5、变量权重值（variable important in projection, VIP）>1.5]，并进一步通过KEGG分析相关代谢通路。n 结果:PCA和PLS-DA模式识别结果显示，各个时间点的C组和S组代谢物之间表现出聚类型分布，不同时间点的C组代谢物之间也呈现聚类型分布。2、6、12 h时点S组与C组之间分别检测出14个、25个和21个差异代谢物。2 h时差异代谢物相关信号通路涉及淀粉和蔗糖代谢、半乳糖代谢；6 h时差异代谢物相关信号通路涉及淀粉和蔗糖代谢、半乳糖代谢、半胱氨酸和蛋氨酸代谢、精氨酸和脯氨酸代谢、甘氨酸-丝氨酸和苏氨酸代谢、花生四烯酸代谢以及氨酰tRNA生物合成；12 h时差异代谢物相关信号通路涉及半乳糖代谢、精氨酸和脯氨酸代谢、精氨酸生物合成、丙氨酸，天冬氨酸和谷氨酸代谢、D-谷氨酰胺和D-谷氨酸代谢以及维生素B6代谢。结论:脓毒症大鼠早期血浆代谢物水平呈现显著性的动态差异，血浆差异代谢物的改变可能参与脓毒症的病理生理学过程。“,”Objective:To determine plasma metabonomic profiles of rats with early sepsis, to find the differential metabolites and related metabolic pathways of sepsis at different time points, and to reveal the pathophysiological changes of sepsis rats in the early stage.Methods:Fifteen 8-week-old male SD rats were randomly (random number) divided into the sham operation group (S group, n n=6) and sepsis group (C group, n n=9). Sepsis rat model was established by cecal ligation and puncture, and rats in the sham operation group only freed the cecum but without ligation and perforation. Plasma was collected from orbital blood at 2, 6 and 12 h after modeling, and metabonomics was determined by gas chromatography-mass spectrometry (GC-MS). The endogenous metabolites were identified by comparing the standard ion fragment spectrum library of NIST database and Feihn metabonomics database. Multivariate regression analysis was carried out through MetaboAnalyst4.0, including principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) to identify the changes of metabolites, screen the related differential metabolites (n P1.5, VIP >1.5), and then further analyze the related metabolic pathways through KEGG.n Results:The PCA and PLS-DA pattern recognition showed that there was a cluster type distribution between the sepsis group and sham operation group at each time point, as well as between sepsis group at different time points. Fourteen, 25 and 21 differential metabolites were respectively detected between S2 h/C2 h group, S6 h/C6 h group and S12 h/C12 h group. The related signal pathways of differential metabolites were starch and sucrose metabolism and galactose metabolism at 2 h; starch and sucrose metabolism, galactose metabolism, cysteine and methionine metabolism, arginine and proline metabolism, glycine, serine and threonine metabolism, arachidonic acid metabolism and aminoacyl tRNA biosynthesis at 6 h; and galactose metabolism, arginine and proline metabolism, arginine biosynthesis, alanine, aspartic acid and glutamate metabolism, D-glutamine and D-glutamate metabolism, and vitamin B6 metabolism at 12 h.Conclusions:The plasma metabolites of sepsis rats in the early stage show significant dynamic differences, and the changes of plasma metabolites may be involved in the pathophysiological process of sepsis.