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ObjectiveTo determine the levels of type Ⅳ collagen and matrix metalloproteinase-9 ( MMP-9 ) in the serum and kidney of rats with the multiple organ dysfunction syndrome ( MODS ) and investigate the mechanism of extracellular matrix damage in renal failure of MODS.MethodsForty adult male Sprague- Dawley (SD) rats were randomly (ramdom number) divided into two groups,namely the normal control group ( n =8 ) and the MODS model group ( n =32 ).The rats of model group were further divided into four sub-groups as per different intervals,6 h,12 h,24 h and 48 h,after modeling (n =8 in each).The animal models of MODS were established by two hits,the left eyeball of each model rat was removed to bleed to 2 ml bloocd/100 g body weight and lipopolysaccharide ( LPS,5 mg/kg) was injected into intraperitoneal cavity of model rats four hours later. The same volume of saline instead was injected intraperitoneally into rats of control group.All rats were sacrificed at different intervals.Creatinine (Cr)and blood urea nitrogen (BUN) were determined by using a Hitachi Automatic Biochemical Analyzer.The histological changes in renal tissue were observed under light microscope and transmission electronic microscope.The levels of serum type Ⅳ collagen and MMP - 9 protein were measured by using enzyme linked immunosorbent assay (ELISA).Type Ⅳ collagen and MMP- 9 protein levels in renal tissue were detected by western blot.One - way ANOVA was used for comparison among multiple groups.Results Compared with the control group,Cr and BUN were significantly higher in MODS group ( P ＜0.05 ).There were no histopathological changes in kidney of rats in control group,and the renal injury was serious in rats with MODS.The remarkable edema of basement membrane and defect of collagen fibers in renal tissue were observed in MODS group.Compared with the control group,the levels of MMP-9 in serum increased 6-48 hours after modeling and peaking at interval of 12 hours after modeling ( P ＜ 0.05 ).The protein levels of type Ⅳ collagen increased not significantly in 6 h group and 12 h group in comparison with control group (P ＞ 0.05 ),while those in 24 h group and 48 h group significantly increased ( P ＜ 0.01 ).The levels of MMP -9 in renal tissue of rats with MODS increased in 6 h group and 12 h group (P＜0.05),peaked in 24 h group ( P ＜ 0.05 ),and decreased in 48 hours.However,the level of Ⅳ collagen in serum of rats with MODS decreased significantly 6-48 hours after modeling (P ＜ 0.05 ) Conclusions The injury of extracellular matrix is an important factor to the kidney damage in MODS and it may he used for early diagnose and as a treatment target for kidney injury in MODS.
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Objective To determine the level of toll-like receptor4 (TLR4) in the kidney of rats with the Multiple Organ Dysfunction Syndrome (MODS),and to investigate the early phase of kidney damage in MODS.Methods The experiment was done at experimental center of medical college of Three Gorges University.Forty Adult male Sprague-Dawley (SD) rats were randomly (random number) divided into two groups,namely the normal control group and the MODS model group.The rats of model group were further divided into four sub-groups as per different intervals (6 h,12 h,24 h and 48 h),and there were 8 rats in each groups.The animal models of MODS were established by two hits,the left eyeball of each model rat was removed to bleed to 2 mL/100 g,and four hours later,Lipopolysaccharide ( LPS,5 mg/kg) was injected into intraperitoneal cavity of model rats.The same volume of saline was injected intraperitoneally into rats of control group.All rats were sacrificed at various intervals.The histological changes in the kidney tissue were observed by naked eye and under light microscope.The lever of TLR4 proteins in serum and kidney tissue were detected by using flow cytometry (FCM).One-way ANOVA was used for comparison among multiple groups.Results (1) There were no histopatholagical changes in kidney of rats in control group,and the kidney injury was serious in rats with MODS.(2) Compared with the rots of control group,the level of TLR4 in kidney tissue of rats with MODS increased at 6 hours and reached peak 12 hours later ( P ＜ 0.01 ),and then decreased 24 hours ( P ＜ 0.01 ).There was no significant difference in levd of TLR4 between two groups 6 and 48 hours.Compared with the rats of control group,the level of TLR4 in peripheral blood leucocyte of rats with MODS increased significantly 6 ～ 48 hours after LPS ( P ＜ 0.01 ).The concentrations of serum and kidney tissue TLR4 proteins were positively correlated with each other ( r =0.893,P ＜ 0.05 ).Conclusions The level of TLR4 markedly increased in the kidney tissue at early stage of MODS,and the TLR4 may play an important role in the pathogenesis of kidney injury in MODS.
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Objective To explore the effect of panaxadiols saponin (PDS) on the oxidative damage in lung tissue in hemorrhage-lipopolysaccharides (LPS) two hits rats. Methods Forty Wistar rats were divided randomly into 4 groups: sham operational group(S group); two hits groups with hemorrhage-LPS(HL group);dexamethasone preventive therapy group (HLD group) ;panaxadiol saponins preventive therapy group(HLP group). The rats were made first-hit by hemorrhagic shock,LPS were administered intraperitoneally to make endotoxic shock and induce two hits in rats,then the model of acute lung injury (ALI) induced by two hits had been built up successfully. NO-2/NO-3,MDA content and NOS,iNOS,SOD activities were measured by 722S spectrophotometer. Results The results of pathological observation showed that there was obvious inflammatory reaction in lung tissues after two-hits,and the structure was destroied.Compared with HL group,the inflammatory reaction was reduced in HLD group and HLD group.NOS,iNOS activities and NO-2/NO-3,MDA contents were increased significantly,and SOD activity was significantly lower in HL group compared with S group(P
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Objective To investigate the alteration of aquaporin 1(AQP1) expression in lung tissues in hemorrhage-lipopolysaccharide(LPS) two-hits rats and the effects of panaxadiols(PDS)and dexamthasone(Dex) on it.Methods The rat model of acute lung injury was built with hemorrhage-LPS two hits.The experiment was divided into control group(S),two-hits model group(HL),DEX group(HLD),and PDS group(HLP).The pathological changes of lung tissue were examined by HE staining.The expression of AQP1 was analyzed by RT-PCR,Western blotting and immunohistochemical staining.Results ① Significant inflammatory changes in pulmonary interstitial of rats in HL group were observed.However,in HLD group and HLP group,the pulmonary pathologic changes were much slighter.② AQP1 mRNA and protein expressions in lung tissues in HL group were significantly decreased compared with others groups(P
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Objective To investigate the effects of radix salviae militiorrhizae (RSM) on acute lung injury induced by"two hits"and to study its probable mechanism.Method Thirty Wister rats were randomly divided into three groups:namely normal control group,model group and RSM treatment group.The model was created by"two-hits"in which 0.2 ml/kg oleic acid was injected into tail vein first,and then 2 mg/kg lipopolysaccharide was administered four hours later.After model rats sacrificed,the pathological changes of lung were observed,and lung wet/dry weight ratio,protein content,and the ratio of neutrophiles in brochoalveolar lavage fluid (BALF) were calculated.In addition,the expression of Fas,FasL protein and apoptosis were evaluated by immunohistochemical studies and TUNEL technique.Results The acute lung injury rat model was successfully induced by"two hits".The gross and micrographic injury of lung was milder in RSM treatment rats than in model rats.The W/D ratio,protein contents and the ratio of neutrophiles in BALF were also markedly reduced in comparison with model rats,while the expression of Fas and Fasl,and the apoptosis index in model rats were significantly increased compared with other two groups.Furthermore,it showed a positive correlation between the expression of Fas,FasL,and the number of cell with apoptosis.Conclusions RSM shows a protective effect on ALT rats caused by"two hits"likely reaulted from inhibiting the expressions of Fas and Fasl,which are associated with the cell apoptosis of lung tissue.