Objective To establish a stable and reliable lung injury model caused by severe acute pancreatitis(SAP)in rats, which is helpful to study the acute lung injury (ALI)and acute respiratory distress syndrome (ARDS) induced by SAP.Methods Sixty Sprague-Dawley rats were randomized into ligature group (n=20), traditional group (n=20),and sham operation group (n=20). SAP model was established through retrograde injection of 5% taurocholic acid. After injection, the pancreatic duct of rats was ligated in ligature group, but not in traditional group. The lung damage and edema at 24 h after operaton and natural course of rats were observed.Results The ALI model of rats induced by SAP was established successfully in ligature group. The rats died of acute respiratory failure within 48 h in ligature group, the mortality was significantly higher than that in traditional group (100% vs.20%),P<0.05. Pleural effusion occurred in four rats in ligature group, while no pleural effusion was found in rats in other two groups. The volume of ascites of rats in ligature group was (21.15±5.33) ml, which was more than that in traditional group 〔(7.75±2.66) ml〕,P<0.05, while no ascites was found in rats in sham operation group. The level of serum amylase of rats in ligature group was (2 470.70±399.73) U/L,which was significantly higher than that in traditional group 〔(1 528.40±289.54) U/L〕 and sham operation group 〔(831.10±93.26) U/L〕,P<0.001. The level of serum albumin of rats in ligature group was (6.90±1.66)g/L, which was significantly lower than that in traditional group 〔(13.10±0.99) g/L〕 and sham operation group 〔(16.20±0.92) g/L〕,P<0.001.The lung wet-to-dry weight ratio (W/D) of rats in ligature group was 6.50±0.23, which was greater than that in traditional group (4.92±0.18) and sham operation group (4.61±0.16), P<0.001. The score of lung histopathologic of rats in ligature group was 29.25±1.07, which was significantly higher than that in traditional group (12.65±1.98) and sham operation group (0),P<0.001. The score of pancreas histopathologic of rats in ligature group was 15.95±0.15,which was significantly higher than that in traditional group (13.75±0.66) and sham operation group (0.13±0.29),P<0.001. Under transmission electron microscope, basement membrane of pulmonary capillary of rats in ligation group was destructive, the nuclei was dissolved, endothelial pinocytotic vesicles was functional active, and tight junctions between capillary endothelial cells were blurred and even ruptured. Moreover, tight junctions between alveolar epithelial cells were destructive. Pathological changes of lung ultrastructure of rats in ligation group were more severe than that in traditional group, while no pathological change of lung ultrastructure was observed in rats in sham operation group. Conclusions Injury process and pathogenesis of ALI or ARDS clinically caused by acute gallstone pancreatitis can be reproduced in this animal model, which is suitable to explore the related mechanisms of ALI caused by SAP and provides good animal model for the study of ALI caused by SAP.
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 determine the risk factors for acute lung injury(ALI) early after orthotopic liver transplantation.Methods The perioperative clinical data of all 275 patients who had undergone orthotopic liver transplantation were analysed retrospectively.Several statistically significant risk factors were screened out with univarite analysis,then independent risk factors were determined with multivariate stepwise logistic regression analysis.Results Of the all 275 patients,the morbidity of ALI was 9.8% with a mortality of 22.2%.Univariate analysis showed that the occurrence of ALI was associated with preoperative infection,severe hepatitis,renal dysfunction,massive blood transfusion in operation,long non-hepatic period and long cold ischemic time.Multivarite stepwise logistic regression analysis revealed that the independent risk factors for ALI were massive blood transfusion in operation(OR=12.12,95%CI 0.958-25.364),longer non-hepatic period(OR=1.23,95%CI 1.034-1.410) and longer cold ischemic time(OR=22.35,95%CI 1.266-43.421).Conclusion Massive blood transfusion in operation,long non-hepatic period and long cold ischemic time were independent risk factors for ALI early after orthotopic liver transplantation.
Objective To study the effects of hyperoxia on ventilator-induced lung injury(VILI) in rats.Methods 48 healthy male SD rats were randomly divided into four groups:Group A received conventional mechanical ventilation(VT=8 mL/kg) with room air,Group B received the same tidal volume as group A with 100% O2,Group C received large tidal volume(VT=40 mL/kg) with room air,group D received the same tidal volume as group C with 100% O2.Arterial blood gases were measured every one hour and oxygenation index(PaO2/FiO2) was calculated.The changes of lung histopathology were assessed by HE staining and observed under light microscope.Wet-to-dry weight ratio(W/D) of left lung,neutrophils and white blood cell(WBC) counts in BALF were measured.TNF-α,IL-1β,and MIP-2 levels in BALF,malondialdehyde(MDA),myeloperoxidase(MPO),and superoxide dismutase(SOD) levels in the lung were assayed,respectively.Results Compared with the Group C,the Group D demonstrated more infiltrating neutrophils in the lung and more destructive changes in the alveolar wall.Meanwhile,the oxygenation index decreased,the WBC and neutrophils counts in BALF increased,and the W/D of left lung was higher in the Group D with significant differences compared with the Group C.Moreover,the BALF levels of TNF-α,IL-1β and MIP-2,the lung levels of MDA increased,and the lung levels of SOD decreased significantly in the Group D compared with those in the Group C.There were no statistical significant differences between the Group B and Group A in all parameters except that MDA levels increased and SOD levels decreased significantly in the Group B.Conclusion Hyperoxia can increase lung injury induced in large tidal volume ventilation in rats,but has mininmal effects in conventional mechanical ventilation.
Objective To investigate the effects of mechanical ventilation on lung pathology and concentration of proinflammatory cytokines in rats.Methods Forty-five healthy Sprague-Dawley rats were randomly divided into three groups with 15 rats each group,ie.a control group(No mechanical ventilation),a high tidal volume group(VT 34 mL/kg,RR 30 bpm) and low tidal volume group(VT 8 mL/kg,RR 60 bpm).Results There were enlarged alveolar spaces,interalveolar septum collapse,swollen and spotty hemorrhages,inflammatory cell infiltration in the ventilation groups,which was more serious in the high tidal volume group.Lung wet-to-dry weight ratio of high tidal volume group was significantly higher than that of other groups(both Plt;0.05).The concentrations in both macrophage-inflammatory protein-2(MIP-2)and tumor necrosis factor-α(TNF-α) of bronchoalveolar lavage fluid(BALF) and blood samples was significantly higher in two ventilation groups than the control group(Plt;0.05),which were higer in the high tidal volume group than in the low tidal volume group(Plt;0.05).Conclusions These results indicate that mechanical ventilation can cause lung injury,which is more serious in high tidal volume ventilation.And mechanical ventilation-induced lung injury can cause proinflammatory cytokines release,with different levels in bronchoalveolar lavage fluid and blood samples.
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 study the effects of two different tidal volume mechanical ventilation on lipopolysaccharide( LPS) -induced acute lung injury( ALI) , and explore the effects of glutamine on ALI.Methods Thirty male Sprague-Dawley rats were randomly divided into three groups. After anesthesia and tracheotomy were performed, the rats were challenged with intratracheal LPS ( 5mg/kg) and received ventilation for 4 hours with small animal ventilator. Group A received conventional tidal volume, while groupB received large tidal volume. Group C received large tidal volume as well, with glutamine injected intravenously 1 hour before ventilation. Arterial blood gases were measured every one hour. 4 hours later, the rats were killed by carotid artery bleeding. The total lung wetweightwas measured and lung coefficient ( total lung wet weight /body weight ×100) was counted. WBCs and neutrophils in BALF were counted. Protein concentration, TNF-α, IL-6, and cytokine-induced neutrophil chemoattractant-1 ( CINC-1) levels in BALF,myeloperoxidase ( MPO) , and superoxide dismutase ( SOD) levels in the lung were assayed respectively.Results PaO2 and SOD levels decreased more significantly in group B than those of group A. The lung coefficient, WBCs, neutrophils, protein, TNF-α, IL-6, and CINC-1 levels in BALF, MPO levels in lung increased more significantly in group B than those of group A. PaO2 and SOD levels were significantly higher in group C than those of group B. The lung coefficient, WBCs, neutrophils, protein, TNF-α, IL-6, and CINC-1 levels in BALF,MPO levels in lung were significantly lower in group C than those of group B. Conclusion Large tidal volume mechanical ventilation aggravates LPS-induced ALI, and glutamine has obviouslyprotective effects.
Objective To study the protective effects of ulinastatin( UTI) on lung function after cardiopulmonary bypass( CPB) . Methods 42 Patients, ASA score Ⅱ ~Ⅲ, scheduled for elective cardiac valve replacement, were randomly allocated into three groups, ie. a control group, a low dose UTI group( UTI 8000U/kg) , and a high dose UTI group( UTI 12 000 U/kg) . Inspiratory pressure( PIP) , Plateau pressure ( Pplat) , alveolar-arterial oxygen pressure difference ( AaDO2 ) , static lung compliance ( Cs) and dynamic lung compliance ( Cd) were recorded before operation ( T1 ) and at 1 hour ( T2 ) , 4 hours ( T3 ) , 24 hours ( T4 ) after CPB termination. Results Compared with pre-CPB, postoperative PIP, Pplat and AaDO2 increased, and Cs and Cd decreased significantly in the control group( all P lt; 0. 05) . Compared with the control group at T2 ~T3 , postoperative PIP, Pplat, AaDO2 were significantly lower( P lt;0. 05) , and Cs and Cd were significantly higher in the two UTI groups( P lt;0. 05) . Compared with the low dose UTI group at T2 ~T3 , the PIP, Pplat and AaDO2 were significantly reduced( P lt;0. 05) , and the Cs and Cd were significantly increased in the high dose UTI group( P lt; 0. 05) . Conclusion UTI can alleviate lung injury and improve lung function during valve replacement surgery with CPB in a dose dependent manner.
Objective To determine if mesenchymal stem cells ( MSCs) could be reconstructed as a vehicle for angiopoietin-1 ( Ang1) gene therapy in lung injury. Methods MSCs were obtained from adult male inbred mice and cultured to passage four. The cells were identified by fluorescence-activated cell sorting ( FACS) analysis and cell differentiation detection. Lentiviral vectors contained GFP and Ang1 gene were conducted in 293T cells through three plasmids co-transfection method. Then MSCs were transduced with Ang1 gene efficiently through lentiviral vectors. The mRNA expression of Ang1 in MSCs was detected by RT-PCR before and after transfection. Also fluorescence from MSCs was detected by fluorescence microscope every day after transfection. Two hours after LPS inhalation, mice were infused via jugular veinwith normal saline ( NS group) , lentiviral vector carrying Ang1 ( Ang1 group) , lentiviral vector carrying GFP ( MSCs group) , and lentiviral vector carrying Ang1 /GFP ( MSCs-Ang1 group) , respectively. Kaplan-Meier survival analysis was performed to compare the effects of MSCs-Ang1 on survival. And ectogenic MSCs origined lung cells were investigated in receipt mice. Results After passaged and purification,MSCs were confirmed to have the potential of differentiation. The lentiviral vectors carrying Ang1 and GFP were also identified. After transfection, the mRNA expression of Ang1 in MSCs was enhanced. Through the fluorescence microscope,MSCs get the most green fluorescence expression five days after the transfection when MOI was 20. Kaplan-Meier survival analysis showed that MSCs-Ang1 infusion had improved survival rates of lung injury rats compared with the control, but it did not reach statistical significance ( P = 0. 066) . Cells expressing GFP in lung tissues can be observed after MSCs were transplanted in vivo. Conclusions MSCs expressing Ang1 high can be constructed through lentiviral vector transfer, and MSCs-origined cells can be detected in receipt lungs after transplantation. So MSCs may serve as a vehicle for gene therapy in lung injury.
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.