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)
Objective The effects of endotoxin, cytokines, nitric oxide were reviewed in the development of hyperdynamic circulatory syndrome in portal hypertension. Methods Liceratures of overseas main studies in hyperdynamic circulatory syndrome of portal hypertension in recent 10 years were reviewed. Results The hyperdynamic circulatory syndrome was found in 30%-50% of patients with cirrhosis and in all animal models of portal hypertension. The research results of the effects of endotoxin, cytokines, nitric oxide in the development of hyperdynamic circulatory syndrome were different. Conclusion Hyperdynamic circulatory syndrome contribute to the maintenance and aggregation of portal hypertension. Endotoxin, cytokines, nitric oxide may play a role in the development of hyperdynamic circulatory syndrome. Nitric oxide is a more important factor. The effect of other factors is probably mediated by nitric oxide.
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.
Objective To compare the vasoactive effects of norepinephrine( NE) and dopamine of different doses on isolated rabbit pulmonary and systemic arteries in septic shock. Methods Six paired pulmonary and systemic arterial rings were prepared fromsix rabbits, and matched randomly assigned into a normal group and a LPS group. The assigned groups were intervened by different doses of NE. Another six paired pulmonary and systemic arterial rings were prepared from another six rabbits. They were assigned to different groups as above and intervened by different doses of dopamine. The LPS groups were pre-incubated in RPMI mediumsupplemented with4 μg/mL LPS to simulate septic shock. The tension of arterial rings was measured and its response to NE and dopamine were studied. Results ( 1) In the normal groups, the contraction of the systemic arteries was ber than the pulmonary arteries in response to low,middle dose of NE, and high dose of dopamine ( all P lt; 0. 05) , and which was weaker in response to middle dose of dopamine and similar in response to high dose of NE( P gt;0. 05) . Both the pulmonary and systemic arteriesrelaxed in response to low dose of dopamine. ( 2) After LPS pre-incubation, the contraction of the systemic arteries was weaker than the pulmonary arteries in response to low dose of dopamine ( P lt;0. 05) , and which was similar in response to low,middle and high dose of NE, and middle, high dose of dopamine. ( 3) Comparing the LPS groups with the normal groups, the contraction in response to middle dose of dopamine increased in the systemic arteries and dreased in the pulmonary arteries ( P lt;0. 05) . Conclusions In septic shock, the vasoactive effect of different doses of NE is not different between pulmonary and systemic arteries. But middle dose of dopamine can increase the contraction of systemic arteries and decrease the contraction of pulmonary arteries.
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.
【Abstract】ObjectiveThere are two main functions of gastrointestinal tract, digestion and absorption, and barrier function. The latter has an important defensive effect, which keeps the body away from the invading and damaging of bacteria and endotoxin. It maintains the systemic homeostasis. Intestinal dysfunction would happen when body suffers from diseases or harmful stimulations. The more serious intestinal disorders would harm the intestinal protective mechanism, or intestinal barrier function, and bacterial/endotoxin translocation, of intestinal failure (IF) would ensue. This article provides a critical review of the evidence indicating that an increase in bacterial translocation is associated with sepsis, and even the multiple organ failure syndrome in critically ill patients. The intransit microorganisms play an essential role in the homeostasis of local and systemic immunity. MethodsAll studies published from 2000 to June 2005 about intestinal permeability, bacterial translocation, and systemic inflammatory response syndrome were located by search of PubMed. ResultsClinical and experimental studies investigating the correlation between bacterial translocation and systemic inflammatory response syndrome, associated with the damage of the gut barrier function . To keep the mucosal barrier function intact is one of the main issues in the prevention of bacterial translocation. This could be achieved by the adequate delivery of oxygen and nutrient supplementation to the gut. Enteral nutrition, probiotic can be a good choice. ConclusionWith a better understanding of the bacteriahost interactions in health and the alterations induced by critical illness, new therapies that improve the environment of both may lead to better recovery rates in intensive care unit patients.
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)
ObjectiveTo investigate the regulatory roles and changes of M3 receptor subtype in lipopolysaccharide (LPS)-preincubated rabbit pulmonary arteries, and assess the mechanism of altered vascular reactivity in septic shock. MethodsPulmonary arteries with intact endothelium were isolated from 26 male New ealand white rabbits weighing 2.0 to 2.5kg. he isolated pulmonary arteries were randomized into two grouops, including a normal group with normal saline and darifenacin adminstration, and an endotoxin group with LPS-preincubation and darifenacin adminstration.he response of arteries to phenylephrine (100μmol/L) and acetylcholine(ACH)(1μmol/L, 10μmol/L, 100μmol/L)were measured in normal and darifenacin-preincubated circumstances. ResultsThe percentages of ralaxation to ACH (1μmol/L, 10μmol/L, 100μmol/L) were (0.095±0.034)%, (0.150±0.036)%, and (0.445±0.090)% in the normal group, and (0.044±0.016)%, (0.093±0.029)%, (0.311±0.028)% in the endotoxin (LPS 4μg/mL, 4h) group. After pretreatment with M3 receptor antagonist darifenacin on different concentrations, the EC50 values responding to ACH (1μmol/L, 10μmol/L, 100μmol/L) were 1.483, 2.757, 2.958 in the normal group, and 6.015, 6.242, 6.411 in the endotoxin group. After pretreatment with M3 receptor antagonist darifenacin on different concentrations, the inherent activity of a value to ACH (1μmol/L, 10μmol/L, 100μmol/L) were 0.0146, 0.0323, 0.0825 in the normal group, and 0.0124, 0.0245, 0.0556 in the endotoxin group. ConclusionsLPS pre-incubation can reduce the relaxation response to ACH, and M3 receptor subtypes mediated this relaxation response. LPS also reduce the M3 receptor subtype intrinsic activity, which may be one of the mechanisms of decreased relaxation response to ACH in pulmonary arteris after LPS pretreatment, and also one of the mechanisms of pulmonary hypertension in septic shock.
Objective To examine the role of recombinant interleukin-10 (IL-10) and the therapeutic effect of endotoxin-induced uveitis (EIU) in rats.Methods Fifty-six male Wistar rats were randomized into three groups. IL-10 treatment group and positive control group had 24 rats respectively, and the normal control group had eight rats. Endotoxin-induced uveitis (EIU) is an established animal model of acute ocular inflammation induced by LPS intravenous injection (1 mu;g/kg). The onset times and signs were observed and the clinical scores were recorded. The blood samples and the aqueous humor samples of right eye were collected separately before the rats were sacrificed at fourth hour, 24th hour and third day after LPS injection. The enzyme-linked immunosorbent assay was used to measure tumor necrosis factor (TNF) alpha;,IL-6, and IL-10 levels in the serum and aqueous humor. The left eyes were used for pathological examination and pathological grading. Results The symptoms of uveitis were appeared in all 24 rats in the positive group. The average onset time was (3.81plusmn;1.05) hours, the average clinical score was 3.67plusmn;1.97. The mild manifestations of uveitis were also appeared in all of the rats in treatment group. The average onset time was (5.63plusmn;1.02) hours, the average clinical score was 2.00plusmn;1.25. The average onset time in treatment group was postponed compared with the rats of positive group (t=4.95, P=0.000). The clinical scores (t=3.50, P=0.00) and the pathological grades (t=3.28, P=0.00) in treatment group were lower than those of positive group. There were not signs or pathologic changes in all the eight rats in the negative control group. The serum and aqueous humor levels of TNF-alpha; and IL-6 in the rats of positive group were higher than those of the treatment group and control group (F=15.34, 57.65, 67.59, 8.42; P=0.00). The serum and aqueous humor levels of IL-10 in the rats of treatment group were higher than those of the positive group and the control group (F=17.84,7.76; P=0.00). There were positive correlations between the level of aqueous humor TNF-alpha;, serum and aqueous humor levels of IL-6 and the disease severity (reye＝0.58, 0.31,0.81, rpath＝0.56, 0.31, 0.74; P＜0.05). The negative correlations were presented between the serum levels of IL-10 with the disease severity (r=-0.54,-0.55; P=0.00). There were negative correlations between the serum and aqueous humor levels of TNF-alpha; and IL-6 and the onset time of the disease (r＝-0.47,-0.59,-0.77,-0.36; P＜0.05) as well. Conclusions These findings bly suggest that suppressive IL-10 is a potent candidate for the prevention of TNF-alpha; and IL-6 in uveitis and could be applied as a novel immunoregulatory agent to control EIU.
Objective To observe the expression of GdCl3 on Toll-like receptors （TLRs） of RAW264.7 from murine macrophage cell line induced by lipopolysaccharide (LPS) stimulation. Methods Cells were divided into 3 groups: blank group, LPS group and GdCl3 group. And these cells dyed by goat anti-mouse TLR2/4 poly-antibody and anti-goat IgG labelled with fluorescein isothiocyanate (FITC). The synthesis of TLR2/4 protein were determined by flow cytometry (FCM) analysis and reverse transcription polymerase chain reaction (RT-PCR) analyzed their gene expression. Cell supernatants were taken to measure TNF-α production following the ELISA (enzyme-linked immunosorbent assay) protocol. Results The expressions of TLR2/4 protein and mRNA in GdCl3 group under action of different concentration of GdCl3〔TLR2/4 protein, 200 μmol/L: (70.2±1.28）％/(66.7±2.59)％, 400 μmol/L: (64.9±1.43)％/(60.4±1.25)％, 2 000 μmol/L: (47.4±0.98)％/(32.1±0.74)％; TLR2/4 mRNA (the value of absorbance), 200 μmol/L: (76.42±2.76)/(101.72±3.14), 400 μmol/L: (75.60±3.76)/(89.65±5.17), 2 000 μmol/L: (64.22±4.67)/(78.44±4.88)〕 were significantly lower than those of in LPS group 〔TLR2/4 protein: (94.4±1.76)％/(95.7±0.87)％, P＜0.01; TLR2/4 mRNA: (127.64±3.25)/(119.82±5.59), P＜0.05, P＜0.01〕. The expression of TNF-α in GdCl3 group under action of different concentration of GdCl3〔200 μmol/L: (2 540±77) pg/ml, 400 μmol/L: (2 041±106) pg/ml, 2 000 μmol/L: (1 020±220) pg/ml〕 was also significantly lower that that of in LPS group 〔(4 688±127) pg/ml, P＜0.01)〕. Conclusion GdCl3 significantly inhibits TLR expression and secretion of TNF-α under the condition of LPS stimulation in vivo.