Objective To investigate the role of endothelin(ET) in lung injury during cardiopulmonary bypass (CPB) and study the possible mechanism of ET-mediated lung injury and the protective effect of ferulic acid(FA) during the procedure. Methods Twelve dogs were randomly divided into 2 groups and models of CPB with pulmonary perfusion were established by perfusion of 4 C FA solution through proximal pulmonary artery in the experiment group while control group only received 4 C crystal cardiac arrest solution without pulmonary perfusion. Changes in the content of ET, NO, malonaldehyde (MDA), dry to wet (D/W) in lung tissue and lung function- related indices PaO2/FiO2, airway pressure (AWP), pulmonary vascular resistance (PVR), lung compliance before and after CPB in both groups were measured respectively. Results ET content increased after CPB in control group (P〈0. 05) ,while experiment group had a lower level of ET than that of control group (P〈0.05); D/W, MDA levels in experiment group decreased (P〈0. 05), but NO content increased (P〈0. 05) as compared with control group. After pulmonary perfusion with FA, PaO2/FiO2 and lung compliance values in experiment group were higher than those of control group (P〈0.05),AWP, PVR values lowered accordingly(P〈0. 05). Lung injury was less severe in the experiment group. Conclusion ET is involved in pathogenesis of lung injury during CPB, FA can effectively reduce lung injury and improve lung function thus having a good protective effect on the lung.
【Abstract】Objective To investigate the role of interleukin-10(IL-10) and interleukin-18 (IL-18) in the pathogenesis of acute lung injury in experimental severe acute pancreatitis.Methods Forty-eight SD rats were divided into control group and SAP group by the random data table. The model of experimental severe acute pancreatitis was established by injection of 3.5% sodium taurocholate into the bili-pancreatic duct. Lung wet weight index, ascities and level of serum amylase, IL-10 and IL-18 were quantitatively measured in different time. Intrapulmonary expressions of IL-10 mRNA and IL-18 mRNA were detected by semiquantitative RTPCR. The histopathology of pancreas and lung were observed under the light microscope.Results Lung wet weight index, ascities, level of serum amylase, IL-10 and IL-18, intrapulmonary expressions of IL-10 mRNA and IL-18 mRNA were significantly increased in SAP group (P<0.01). The level of serum IL-18 and intrapulmonary expression of IL-18mRNA are positively correlated with lung wet weight index (r=0.68,P<0.01; r=0.72,P<0.01) and lung injury score (r=0.74,P<0.01; r=0.79,P<0.01) respectively, whereas the level of serum IL-10 and intrapulmonary expression of IL-10 mRNA are negatively correlated with lung wet weight index(r=-0.62,P<0.01; r=-0.69,P<0.01) and lung injury score(r=-0.66,P<0.01; r=-0.60,P<0.01). Conclusion IL-18 may play a key role in the pathogenesis of acute lung injury in experimental severe acute pancreatitis, and IL-10 exerts the protection role in this process.
Objective Observing the expressions of inducible nitric oxide synthase (iNOS) and endothelial nitric oxide synthase (eNOS) mRNA in lung tissues of rats with acute necrotizing pancreatitis (ANP) to explore the role of NOS in ANP associated-lung injury. Methods Forty Wistar rats were assigned into ANP group (n=30) and sham-operation group (SO group, n=10). ANP model was induced by retrograde injection of 5% sodium taurocholate into the bili-pancreatic duct. Pathological changes of the lung tissue were observed under light microscope at 3 h, 6 h and 12 h after the ANP-model operation, and the expressions of iNOS mRNA and eNOS mRNA in lung tissue were assayed by RT-PCR. Results Different degrees of pathological changes of the lung tissue, such as hyperemia, edema, inflammatory cells infiltration, hemorrhage and necrosis, were found in the ANP group. The pathologic injury scores of lung tissue in ANP group were higher than that in SO group (Plt;0.05), and gradually increased with the duration extension of ANP (Plt;0.05). Compared with the SO group, the expressions of iNOS and eNOS mRNA in ANP group were all higher at 3 h, 6 h, and 12 h (Plt;0.05). Conclusions The overexpressions of iNOS and eNOS mRNA may play important roles in lung injury of ANP. This provides us a theory basis that lung injury of ANP could be relieved by inhibiting the expressions of iNOS and eNOS mRNA.
ObjectiveTo summarize the changes and interaction of the cytokine in severe acute pancreatitis associated lung injury. MethodsThe published literatures at domestic and aboard in recent years about severe acute pancreatitis associated lung injury were collected and reviewed. ResultsThe cytokines had a chain effect, and influenced each other when severe acute pancreatitis with lung injury attacked. ConclusionsRelated cytokines play important roles in severe acute pancreatitis associated lung injury. Researching the related cytokines will contribute to the diagnosis and treatment for severe acute pancreatitis with lung injury.
Objective To explore the effects of exogenous ubiquitin on lung injury and serum nitric oxide ( NO) level of mice in the early stage of sepsis induced by cecal ligation and perforation ( CLP) . Methods Seventy-seven mice were devided randomly into three groups, ie. CLP Group ( n =28) , SHAM Group ( n =28) and UB Group( n = 21) . Six hours after operation, seven mice of both Group CLP and SHAM were sacrificed for lung and blood sampling. Meanwhile all mice of Group UB were injected intravenously with exogenous ubiquitin of 10 mg/kg body weight. Seven mice of each group were sacrificed at seven, eight and nine hours after operation. Lung water content and serum level of nitrate /nitrite ( NO2 /NO3 , the stable end-products of NO) , were determined. Pathological changes of lung were compared among the groups. Results Lung water content of Group UB was lower than that of Group CLP at each observational time point. Futhermore, there was a significant differentce in lung water content between Group UB and CLP at 9 hours. Pathological examination revealed that inflammatory hyperemia and infiltration of pulmonary parenchyma reduced in Group UB, compared with Group CLP. Serum NO levels of Group CLP and UB were similar at each time point. Conclusions In the early stage of murine sepsis induced by CLP, a single introvenous bolus of exogenous ubiquitin significantly decreases lung capillary vascular permeability, and probably makes a temporal reduction of acute lung injury while it has no obvious effects on serumNO level.
Objective To investgate the expression of p38 mitogen-activated protein kinase (p38MAPK) in lung tissue of rats with severe acute pancreatitis (SAP), and to explore the relationship between p38MAPK and pulmonary capillary barrier injury. Methods Forty male and healthy Sprague-Dawley (SD) rats were randomly (random number method) divided into sham operation (SO) group and SAP group, then rats of SAP group were sub-divided into 3, 6, 12, and 24 h group, each group enrolled 8 rats, respectively. SAP model rats were established by injecting 5% sodium taurocholate solution retrograde into the biliopancreatic duct. ELISA method was used to test the serum tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), and pathological changes in lung and pancreas tissues were observed by HE staining. Immunohischemistry method was used to detect phosphorylated p38 (p-p38) protein and aquaporin 1 (AQP1) protein of lung tissues. The expression level of AQP1 mRNA was measured by quantitative real-time PCR. Results Hyperemia, edema, and inflammatory cell infiltration were observed in lung tissues, abundance of necrosis, part gland structure fuzzy or even disappear were observed in pancreas tissues of all 4 time point groups. Compared with SO group, levels of serum TNF-α and IL-1β were significantly higher in 4 time point groups (P<0.05). Lower expression level of p-p38 protein was detected in lung tissues of SO group, while in the early stage of SAP (SAP 3 h group), the expression level of p-p38 protein significantly increased, which peaked in 6 h group and was still higher than SO group in 24 h group (P<0.05). Compared with SO group, the expression levels of AQP1 mRNA and protein were significantly lower in all 4 time point groups (P<0.05), which had negative correlation with the levels of serum TNF-α,IL-1β, and the expression level of p-p38 protein (r=-0.87, P<0.05;r=-0.88, P<0.05;r=-0.78, P<0.05). Conclusion The decrease of AQP1 protein in lung tissue is one of the vital causes for pulmonary capillary barrier injury in SAP, which probably works by the activation of p38MAPK and the excessive release of inflammatory cytokines.
Objective To observe the effects of melatonin on lung injury and NDRG2 ( N-myc downstream-regulated gene 2) expression after intestinal ischemia-reperfusion ( I/R) .Methods 40 healthy SD rats were randomly assigned to a sham group, an I/R group, a high-dose melatonin group ( 10 mg/kg) , and a low-dose melatonin group ( l mg/kg) . The model of lung injury was established by superior mesenteric artery clamping/unclamping. 30 minutes before clamping, melatonin was administered intraperitoneally to the rats in two melatonin groups, and normal saline in same volume was administered to the rats in the I/R group and the shamgroup. Then superior mesenteric arteries of the rats in the I/R group and two melatonin groups were clamped for 60 minutes. 45 minutes after unclamping, right lung tissues were sampled for pathological examination and wet/dry ( W/D) ratio measurement. The rats in the sham group underwent sham operation without clamping. The expression of NDRG2 protein in the lung tissue was detected by immunohistochemistry and Western-blot. Results Compared with the sham group, hemorrhage and inflammation of lung tissues were observed. The W/D was obviously increased and the NDRG2 expression was significantly decreased in the I/R group. Compared with the I/R group, mild hemorrhage and inflammation changes of lung tissues were observed and the W/D was decreased while the NDRG2 protein expression was increased significantly in two melatonin groups. There was no significant difference between two melatonin groups. Conclusion Melatonin may relieve lung injury after intestinal ischemia-reperfusion through up-regulating NDRG2 expression.
The contents of lipid peroxides(LPO)and vitamin E(V.E)and some functional index and histologic changes in the lungs from the the rabbit models of acute cholangitis of severe type(ACST)were measured dynamically.The results revealed that the V.E content decreased strikingly from 6 hours and the LPO level increased progressivelg from 12 hours in the lungs.Simultanuosly,the congestion and neutrophil infiltreation in the lung mesenchyme,and the endothelial cell damage and thrombosis in the lung blood capillaries had been observed.These suggest that acute lung injury induced by ACST is referable to the lipid peroxidation damage to the lung blood capillaries which is due to increased LPO and decreased antioxidants including V.E.
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.
Objective To investigate the effects of recombinant human erythropoietin ( rHuEPO) on expressions of Bax and Bcl-2 proteins in hyperoxia-induced lung injury of adult rats. Methods Fortyeight healthy male SD adult rats were randomly divided into six groups. The control group ( 0 h) breathed with room air. The rHuEPO intervention group was put into oxygen chamber and breathed with 100% O2 for 96 h plus intraperitoneal injection of rHuEPO (1000 U/kg) daily. Other four groups were put into oxygen chamber and breathed with 100% O2 for 24, 48, 72 and 96 h respectively. Arterial blood gases were measured to calculate oxygenation index. Wet-to-dry weight ratios of left lung were measured. The contents of TNF-α and IL-1β in bronchoalveolar lavage fluid (BALF) were assayed with radioimmunoassay. The expressions of Bax and Bcl-2 proteins in the lung were determined withWestern blot and immunohistochemisty. The changes of lung histopathology were assessed by hematoxylin and eosin stain and observed under light microscope. Results After breathing 100% O2 , the oxygenation index decreased gradually and reached minimal value at 96 h. The wet-to-dry weight ratio of left lung increased gradually and reached maximal value at 96 h. The contents of TNF-α and IL-1β in BALF reached maximal value at 48 h and then decreased gradually. The expression of Bax protein increased, but the expression of Bcl-2 protein decreased gradually in the lung. Compared with the 96 h group, the oxygenation index was higher, wet-to-dry weight ratio and contents of TNF-α and IL-1β in BALF decreased, the expression of Bax protein decreased, and the expression of Bcl-2 protein increased in the lung of the rHuEPO group. Conclusion rHuEPO can attenuate hyperoxia-induced lung injury of adult rats by down-regulating expression of Bax protein and up-regulating expression of Bcl-2 protein.