氯化镧对烫伤鼠肠道细菌移位的防治研究

目的　探讨氯化镧对烫伤鼠肠道细菌移位的作用及其机制。　方法　SD大鼠分为正常对照组 (A)、烧伤对照组 (B)及烧伤治疗组 (C) ,每组 30只。采用PUC19质粒转染大肠杆菌示踪加限制性内切酶指纹图谱分析法 ,对肠道菌向肠系膜淋巴结 (MLN)及血液中的播散进行示踪及定量研究。　结果　阳性菌落经酶切图谱分析后 ,证实B、C组MLN匀浆及血液培养生长细菌与灌胃的细菌具有完全相同的酶切图谱 ;C组MLN菌量在伤后 3、5d低于B组 (P <0 .0 5 )。C组血细菌阳性率在伤后 3d低于B组 (P <0 .0 5 )。C组血ET、NO及NOS量在伤后 1、3、5d均低于B组 (P <0 0 1)。C组肠组织MDA量在伤后 1、3、5d低于B组 (P <0 .0 1) ,C组肠组织SOD量在伤后 1、3d高于B组 (P<0 .0 5 )。　结论　血和MLN培养出的细菌由肠道细菌移位而来 ;氯化镧能有效防治肠道细菌移位 ;氯化镧通过抗菌、降低血中的ET、抑制NOS的活性减少NO的生成、提高SOD的活性并使MDA的产生下降等途径减少肠道细菌移位。

An exploration of the preventive effect of lanthanum chloride on enteral bacterial translocation in scalded rats

OBJECTIVE: To explore the preventive effect of lanthanum chloride on enteral bacterial translocation in scalded rats. METHODS: Ninety Sprague-Dawley (SD) rats were employed in the study and randomly divided into three groups, i.e. normal control (A), burn control (B) and treatment (C) groups. Plasmid PUC19 labelled by JM109 was transfected to Escherichia coli (E. coli), so that restriction endonuclease finger - print image spectrum analysis could be applied to the tracing and quantification of the translocation of E. coli from intestine to mesenteric lymph nodes (MLNs) and blood. The intestinal tissue contents of endotoxin (ET), nitric oxide (NO), nitric oxide synthase (NOS), malondialdehyde (MDA) and superoxide dismutase (SOD) were determined. RESULTS: It was identified that the bacteria in MLNs and blood exhibited the same gene map with those from gastric gavage in B and C groups. But the bacterial quantity in MLNs in C group on 3 postburn day (PBD) was much lower than that in B group (P < 0.05). The intestinal MDA content in C group on 1 and 3 PBDs was obviously higher than that in B group (P < 0.05). CONCLUSION: Bacteria (E. coli) could be translocated from gut to MLNs and blood, which could be evidently alleviated by lanthanum chloride by means of its bactericidal property, inhibition of NOS activity, so that NO production decreased, and its ability to increase SOD activity leading to less production of MDA.