Objective To observe the expression of matrix metalloproteinase-9 (MMP-9), its tissue inhibitor of matrix metalloproteinase (TIMP-1), inducible nitric oxide synthase (iNOS) and contents of nitric oxide (NO) in the ocular tissues of Sprague-Dawley (SD) rats with endotoxin induced uveitis（EIU）. Methods Ninety SD rats were randomly divided into experimental (81 rats) and control group (9 rats). The model of EIU was induced in rats in experimental group by injecting with lipoplysaccharide (LPS) 200 μl into the hind feet pads, while the rats in the control group were not injected. Nine rats were executed 0, 6, 12, 18, 24, 48, 72, 96 hours and 7 days, respectively, after injecting with LPS; the NO content and concentration of protein in the aqueous humor in blood plasma, aqueous humor, and uveal tissues were detected. The expressions of MMP-9, TIMP-1 and iNOS in the ocular tissues were detected by immunohistochemistry, and the average absorbance (A) value was evaluated by computer medical image analysis system. Results iNOS, MMP-9 and TIMP-1 expressed in the epithelial cells of iris and ciliary body and exudated inflammatory cells of rats. The concentration of protein in the aqueous humor, the contents of NO in blood plasma, aqueous humor, and uveal tissues, and A value of MMP-9 had obvious relativity with the inflammatory extent, while no positive correlation was found between the inflammatory extent and the A value of iNOS and TIMP-1. Expression of iNOS was found 6 hours after injection, reached the peak after 12 hours, and then dropped gradually. The expression of TIMP-1 could be seen 24 hours after injection, and reached its peak after 72 hours. Conclusion The content of NO and expressions of iNOS, MMP-9 and TIMP-1 changes from the beginning and during the development of EIU, which suggests that NO, iNOS, MMP-9 and TIMP-1 are involved in the pathologic process of EIU. (Chin J Ocul Fundus Dis, 2005, 21: 371-374)
The purpose of this study was to determine the contribution of endotoxin (ET) in ocurrence and progression of acute pancreatitis (AP). The results indicated that correlation of ET changes with multiple organ damage in AP. The degree of ET elevation correlated well with the severty of AP. The level of plasma ET of severe AP patients was much higher than that of mild AP patients (Ｐ＜0.05). The chance of multiple organ damage got greater while the plasma ET level got higher. Moreover, the severety change of severe AP correlated with the change of plasma ET level. In other words, the ET level was reduced while the disease was recovering, elevated while it was becoming worse and maintained high level in dead cases. We think that plasma ET level can be used as a reference for differenciating mild AP with severe AP and a predictor for the prognosis of AP.
PURPOSE: To investigate the influence of transforming growth factor-beta (TGF-beta;) on endotoxin-induced uveitis (EIU). METHODS: TGF- beta; was abstracted from humam platelets using Bio-gel P-60 chromatography. It was introduced either topically(drops) or intraperitoneally into the SD rats after footpad injection of lipopolysaccbaride(LPS). The inflammation in the anterior uvea was clinically evaluated with slitlamp every day. RESULTS :TGF-beta; obtained from Biogel P-60 chromatography displayed single band on SDS-PAGE,showing a molecular weight of 12 500 EIU occurs significantly earlier and more severe in the rats which only received LPS injection than in the TGF-beta; treated rats. The duration of the inflammation was also much longer in the untreated rats than in the treated rats (P＜0. 001). CONCLUSION: TGF-beta; purified from human platelets may partly prevent the development of EIU and effectively reduce the severity of the inflammation induced by LPS injection. （Chin J Ocul Fundus Dis,1996,12: 101-104)
To study the role of endotoxin in acute hemorrhagic necrotizing pancreatitis (AHNP), the change of endotoxin were studied in rats AHNP models by injection of 5% sodium taurocholate 1 ml/kg into pancreatic duct, and the effects of recombinant interleukin-2 (IL-2) in the treatment of AHNP were observed in this experiment. The results indicated that endotoxin involved the aggravation of AHNP and was associated with the increase of serum phospholipas-2 (PLA2), and these mediators were positively correlated with severe degrees of pancreatic damage. The results also suggeste that IL-2 might inhibit the overexpression of endotoxin and PLA2 and mitigate the pancreatic injury and decrease the 72h-mortality rate of AHNP from 66.7% to 26.7% (Ｐ＜0.01). Endotoxin might play a major role in the pathogenesis of AHNP and IL-2 might have a potential role in the treatment of AHNP.
ObjectiveTo explore the effect of endotoxin on insulin secretion from islet βcell of rat pancreas.MethodsAfter the model of endotoxemia was established in rats with intraperitoneal injection of LPS (2 mg/kg),the changes of insulin level in the serum and pancreas were dynamically determined, the expression of inducible nitric oxide synthase (iNOS) by situ hybridization and DNA damage in islet cells were also observed, the effect of sodium nitroprusside (exogenous NO) on synthesis and secretion of insulin from isolated islet βcell of normal rat pancreas under high glucose stimulation was also evaluated.ResultsThe level of glucose and insulin in plasma were significantly increased at 12th and 6th h, respectively and kept on 3 d after injection of LPS,but the insulin level in pancreas was not remarkably altered.The expression of iNOS and DNA damaged significantly enhanced at 6 d after endotoxemia. The high glucosestimulated insulin synthesis and secretion were bly inhibited by exogenous NO.ConclusionThese findings suggest that LPS be stimulate the expression of iNOS and NO product,which inhibites synthesis and secretion of insulin in islet βcells,but it stimulates insulin secretion by another mechanism,and results in dysfunction and destruction of the rat pancreas.
PURPOSE:To investigate and changes of the retina and the chorid induced by lipopolysaccharide (LPS)in Lewis rats and to compare the results obtained on tissue wholemounts and sections. METHODS:Immunohistochemistry was carried out both on wholemounts of the retina and the chorid-sclera complex and on ocular sections from normal Lewis rats and those after LPS injection. RESULTS:It was shown on the tissue wholemounts that monocytes were attached to retinal blood vessels and emigrated into the choroid as early as 4hrs after LPS injection. Severe involvement of the retina and macrophages into whole area of these tissues.Furthermore increasing number of major histocompatibility complex classⅡ(MHC classⅡ)positive cells was observed in the choroid.The results on tissue sections revealed that the retina and the choroid were both involved as videnced by infiltration of these cells at some time points after LPS injection. CONCLUSION:Wholemount technique provides undoubtful evidences to show that the retina and choroid are primarily and severely involuted after LPS injection.The endotoxin induced uveitis is,for the first time,presumed to be model for human generalized uveitis. （Chin J Ocul Fundus Dis,1996,12:33-36）
TO investigate the relationship between endotoxemia and structural change in the pancreatic tissue and therapeutic effects of naltrexone (NTX) on experimental acute hemorrhagic necrotizing pancreatitis in rats. The model of acute hemorrhagic necrotizing pancreatitis (AHNP) of rats was induced by retrograde injection of 5% sodium taurocholate into the pancreatic duct. One hundred and ten Wistar rats were randomly divided into three groups: control group (n=20),AHNP group (n=45) and NTX treatment (n=45) group. The weight of pancreas and plasma levels of amylase and endotoxin were measured as well as changes of the pancreatic histology were examined by light and electric microscope in 6h, 12h, 24h after operation. Results as compared with control groups , amylase and endotoxin in AHNP group were significantly higher in the plasma and the damage to pancreatic tissue was increased in severity as observed with light and electric microscopes in 6h, 12h, 24h after operation. Comparison between NTX treatment groups with AHNP groups demonstrated that amylase and endotoxin were significantly decreased in the plasma, and the damage to pancreatic tissue was reduced in NTX treatment phase. Conclusion these results showed that endotoxemia was induced by AHNP, but NTX decreased the edotoxin level in the plasma and improved the damage of pancreatic tissue. The lethality was significantly lowered and average survival time was prolonged during NTX treatment of AHNP.
Objective To observe the effect of glutamine （Gln） on intestinal permeability after surgery of children, also its influence on the plama level of interleukin-2（IL-2）, endotoxin and synthesize of protein through a random nutrition trial. Methods Twenty children suffered from congenital heart disease were divided into Gln group and control group with random number table, 10 cases in each group. They were all given isonitrogenous and isocaloric total paraenteral nutrition after 24 h postoperatively. In Gln group the Dipeptiven [-N （2）-L-alanyl-Lglutamine] was used with 2 ml/kg · 24h additionly. Before operation, 24h and 96 h after operation, intestinal permeability, serum level of endotoxin, IL-2, C-reaction protein, prealbumine were measured. Results Intestinal permeability increased in 24 h after cardiac surgery in two groups, while the concentration of endotoxin also increased, 96 h after surgery the intestinal permeability recovered, but the endotoxin level did not decrease in control group （P〈0. 01）. Conclusion Utilization of Gln can improve immune suppression, elevate the IL-2 level, decrease the endotoxin concentration, alleviate the infection, but has no effect on the protein synthesis after congenital cardiac operation of children.
Objective To observe the histopathologic features and expression patterns of tumor necrosis factor-alpha; （TNF-alpha;）, interleukin-1beta;（IL-1beta;） and Escherichia coli lipopolysaccharide (LPS) in the rat vitreous with LPS inducedendophthalmitis. Methods Wistar rats were randomly divided into saline control group (SC,136 rats）,endophthalmitis group （EO, 168 rats）and blank control group （BC,12 rats）.EO group received an intravitreal injection of 5 mu;l LPS; SC group received 5 mu;l sterile saline and no intervention for BC group.Six,12,24,48, and 72 hours,5 and 7 days after injection, intraocular inflammation were observed and the eyes and vitreous were collected for histopathological examination and measurement of TNF-alpha;, IL-1beta; and LPS expression. Results Severe inflammatory responses in the eyes were observed in EO group between six and 72 hours after LPS injection，ocular inflammation subsided seven days after LPS injection. In the vitreous, a peak neutrophil count was observed at 24 hours （1224.64plusmn;132.2） cells/eye that rapidly declined at 72 hours （342.25plusmn;47.7） cells/eye. The levels of TNF-alpha; and IL-1beta; in EO group were peaked at 24 hours with （996.18plusmn;89.45） and（5556plusmn;1440）pg/ L, respectively；Persisted at 48 hours and began to decline rapidly thereafter. Seven days after LPS injection, levels of TNF-alpha; and IL-1beta; returned to baseline with （22.16plusmn;5.84）and （73.7plusmn;18.7） pg/L, respectively. LPS concentration in EO group decrease rapidly at 72 hours with （11.03plusmn;3.41） ng and disappear on days 7 with (0.22plusmn;0.08) ng after LPS injection.Conclusions Massive neutrophils infiltration, high levels expression of TNF-alpha; and IL-1beta; and spontaneous elimination of bacterial elements in vitreous cavity were major pathologic characteristics in this experimental model. The expression patterns of TNF-alpha;,IL-1beta; were in accord with LPS clearance process.
Objective To investigate the protective effects of endotoxin pretreatment on lung injury of rats with endotoxemia. Methods The rat model of acute endotoxemia was established by injecting lipopolysaccharide (LPS) intraperitoneally. Seventy-two male Wistar rats were randomly divided into three groups, ie. a saline control group (N, n=24) , a LPS-treated group (L, n=24) , and a LPS pretreated group ( P, n=24) . Each group was divided into 2 h, 4 h, 6 h, and 12 h subgroups. The rats in group P were firstly administered with introperitoneal injection of 0.25 mg/kg LPS. After 24 hours, they were subjected to the injection of 0.5 mg/kg LPS. The rats in group N and L received injection of equivalent amount of saline. After 72 hours, the rats in group L and P were challenged with intravenous injection of 10 mg/kg LPS, otherwise saline in group N. Six rats were killed at 2, 4, 6 and 12 hours respectively after injection of LPS in group L and P. The lungs were removed for detecting intercellular adhesion molecule-1 ( ICAM-1) , superoxide dismutase ( SOD) , and malondialdehyde (MDA) . Meanwhile the level of tumor necrosis factoralpha ( TNF-α) in serum was measured, and the pathological changes of lung were also examined. Results The contents of ICAM-1, MDA and TNF-α in the LPS-treated 4 h group were 75.07 ±0. 53, ( 3.93 ± 0.42) μmol/g, and (478.62 ±45.58) pg/mL respectively, significantly higher than those in the saline control group. The endotoxin pretreatment reduced the above indexes to 42.40 ±0.44, ( 2.89 ±0.49) μmol / g and ( 376.76 ±43.67) pg/mL respectively (Plt;0.05) . The content of SOD in the LPS-treated 4 h group was ( 6.26 ±0.31) U/mg, significantly lower than that in the saline control group. The endotoxin pretreatment increased SOD to ( 8.79 ±0.35) U/mg. Conclusion Endotoxin pretreatment can suppress the progress of lung injury in rats with endotoxemia and protect the lung tissue by down-regulating the inflammatory response and oxygen free radical production.