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Objective To investigate the effect of intratracheal injection of c-Jun N-terminal kinase ( JNK) siRNA plasmid on ischemia-reperfusion ( I∕R) injury in a rat model of lung transplantation. Meth-ods ExperimentⅠ Thirty-two male Wistar rats, weighing 250-280 g, were divided into 2 groups ( n=16 each) using a random number table method: control group ( group C) and JNK siRNA group. JNK siR-NA plasmid 2 mg∕kg ( diluted to 0. 2 ml in sterile phosphate buffer solution) was intratracheally injected in JNK siRNA group. Scrambled siRNA plasmid 2 mg∕kg ( diluted to 0. 2 ml in sterile phosphate buffer solu-tion) was intratracheally injected in group C. Six rats in each group were sacrificed at 48 h of administra-tion, and left lung tissues were removed for determination of the expression of JNK and JNK mRNA ( by Western blot and real-time polymerase chain reaction, respectively) . The other 10 rats left in each group were used for left lung transplantation. Experiment Ⅱ Thirty male Wistar rats, weighing 250-280 g, were divided into 3 groups ( n=10 each ) using a random number table method: sham operation group ( group S) , transplanted lung I∕R group ( group I∕R) and transplanted lung I∕R+JNK siRNA group ( group I∕R+JNK siRNA) . In group I∕R and group I∕R+JNK siRNA, the left lung transplantation was performed, and the donor lungs were obtained from the living donors in group C and group JNK siRNA, respectively. At 15 min of mechanical ventilation and 30, 60, 90 and 120 min of reperfusion, arterial blood samples were obtained for blood gas analysis, PaO2 was recorded, and the oxygenation index ( PaO2 ÷ FiO2 ) was calculated. Arterial blood samples were obtained at 120 min of reperfusion in transplanted lungs for determi-nation of concentrations of interleukin-8 (IL-8), tumor necrosis factor-alpha (TNF-α) and interferon-γ( IFN-γ) in serum ( using enzyme-linked immunosorbent assay) , and the rats were sacrificed and left lung tissues were removed for microscopic examination of the pathological changes which were scored and for de-termination of wet∕dry lung weight ratio ( W∕D ratio) , and nuclear factor kappa B ( NF-κB) and activator protein-1 ( AP-1) activities ( using enzyme-linked immunosorbent assay) . Results ExperimentⅠ Com-pared with group C, the expression of JNK and JNK mRNA was significantly down-regulated in group JNK siRNA (P<0. 05). ExperimentⅡ Compared with group S, the oxygenation index was significantly de-creased, and the concentrations of serum IL-8, TNF-α and IFN-γ, W∕D ratio, lung injury score and ac-tivities of NF-κB and AP-1 were increased in I∕R and I∕R+JNK siRNA groups ( P<0. 05) . Compared with group I∕R, the oxygenation index of receptors were significantly increased, and the concentrations of serum IL-8, TNF-α and IFN-γ, W∕D ratio, lung injury score and activities of NF-κB and AP-1 were decreased in group I∕R+JNK siRNA ( P<0. 05) . Conclusion Intratracheal injection of JNK siRNA can reduce trans-planted lung I∕R injury, and the mechanism may be related to inhibiting inflammatory responses of rats.
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Objective Using small interfering RNA (siRNA) against p38 and simulated lung transplantation model,we discussed the effect of p38 siRNA on hypoxia/reoxygenation injury of pulmonary microvascular endothelial cells (PMVECs) after lung transplantation.Methods We transfected the PMVECs with p38 siRNA or non-targeting (NT) siRNA.After 48 h,these cells were exposed to simulated ischemia-reperfusion.At 2 h and 4 h of reperfusion,we detected lactate dehydrofenase (LDH) leakage rate,malondialdehyde (MDA) levels,superoxide dismutase (SOD) activity,cell apoptosis,and the serum levels of interleukin (IL)-1,IL-6 and tumor necrosis factor (TNF)-α.Protein levels of p38,NF-κB and AP-1 were detected.Untreated PMVECs served as the negative control.Results As compared with NT siRNA,p38 siRNA reduced LDH leakage rate (22.3 ± 5.7 vs.45.1 ± 6.2 and 46.3 ± 7.3 vs.75.6 ± 12.4),decreased MDA levels (4.1 ± 2.2 vs.7.1 ± 2.1 and 3.9 ± 0.5 vs.6.1 ± 1.2),increased SOD activity (12.8 ± 3.2 vs.9.4 ± 1.1 and 10.8 ± 1.2 vs.7.0 ± 1.1),and inhibited apoptosis (2.8 ± 0.6 vs.4.1 ± 1.4 and 3.1 ± 1.1 vs.5.8 ± 1.3).p38 siRNA reduced the levels of IL-1 (288 ± 89 vs.592 ± 95 and 380 ± 94 vs.775 ± 175) and IL-6 (38 ± 5 vs.70 ± 12 and 80 ± 20 vs.118-± 17),however,had no influence on TNF-α level.Silencing p38 gene decreased phosphorylation of p65 and inhibitor of nuclear factor kappa-B kinase β,and increased inhibitor of nuclear factor kappa-B expression.However,p38 siRNA had no effect on the phosphorylation of c-Jun and c-Fos.Conclusion Through inhibiting the NF-κB classic activation pathway,p38 siRNA reduced oxidative stress,inflammation and apoptosis of rat PMVECs,protected membrane integrity,and reduced hypoxia/reoxygenation injury.
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Objective To explore the effect of ultrasound-guided stellate ganglion block (SGB) in the incidence of postoperative headache, nausea and vomiting in conventional thyroidectomy. Methods Ninety patients undergoing conventional thyroidectomy were randomly allocated to three groups with 30 patients in each group. In group L, SGB was performed with 5 ml 0.5% lidocaine; in group N, SGB was performed with 5 ml 0.9% sodium chloride; and in group C, no prior block was performed. Postoperatively, during the 48 h after surgery, every episode of postoperative headache and postoperative nausea and vomiting was recorded and a safety assessment was performed. In group L and group N, the hemodynamic status of the vertebral artery and carotid artery was recorded before and after the SGB was performed. In group C, the hemodynamic status of the vertebral artery and carotid artery was recorded before and after the neck was in the full extension position. Results One patient of group N and one patient of group C was discharged. During the 48 h after surgery, headache occured in 5 patients (16.7%) of group L, 8 patients (27.6%) of group N, and 17 patients (58.6%) of group C, and the headache rate in group C was significantly higher than that in group L (P=0.0007). The headache mostly occurred at 2 h and 4 h after operation. During the 48 h after surgery, nausea and vomiting occured in 8 patients (26.7%) of group L, 11 patients (37.9%) of group N, and 20 patients (60.9%) of group C, and the nausea and vomiting rate in group C was significantly higher than that in group L (P=0.0017) and group N (P=0.0343). The nausea and vomiting mostly occurred at 2 h and 4 h after operation.In group L and group N, and the inner diameters of the vertebral and carotid arteries after SGB were wider than those before SGB (P<0.05). In group C, the inner diameters of the vertebral and carotid arteries after the neck extension position were narrower than prostration position (P<0.05). No side effects were observed during or after SGB. Conclusions Preoperative SGB performed with 5 ml 0.5%lidocaine is an effective technique for reducing postoperative headache and nausea and vomiting after thyroidectomy.
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Objective To evaluate the protective effect of therapeutic hypercapnia on the lung during one-lung ventilation (OLV) in the patients undergoing pulmonary lobectomy.Methods Fifty patients of both sexes,aged 20-60 yr,with body mass index 18-30 kg/m2,of American Society of Anesthesiologists physical status Ⅱ,scheduled for elective pulmonary lobectomy,were randomly divided into 2 groups (n=25 each) using a random number table:control group (group C) and therapeutic hypercapnia group (group H).After induction of general anesthesia,the patients were endotracheally intubated and mechanically ventilated in volume-controlled mode.The ventilator settings were adjusted during two-lung ventilation to maintain the end-tidal pressure of carbon dioxide (PETCO2) at 25-35 mmHg.Group H inhaled the mixture of CO2 (3％-6％) and O2 (70％-82％) during OLV to maintain PETCO2 at 50-60 mmHg.Group C inhaled O2 (70％-88％) during OLV to maintain PETCO2 at 25-35 mmHg.Anesthesia was maintained with inhalation of sevoflurane and intravenous infusion of remifentanil.Immediately before OLV and at 30 min after restoration of two-lung ventilation,the airway peak pressure,airway plateau pressure and lung compliance were recorded,arterial blood samples were collected for blood gas analysis,and broncho-alveolar lavage fluid (BALF) from the collapsed lung and venous blood samples were collected for determination of tumor necrosis factor-alpha (TNF-α),interleukin-1beta (IL-1β),IL-6,IL-8 and IL-10 concentrations in BALF and serum by enzyme-linked immunosorbent assay.Oxygenation index was calculated.Results Compared with group C,the airway peak pressure and airway plateau pressure were significantly decreased,the lung compliance was significantly increased,the concentrations of TNF-α,IL-1β,IL-6 and IL-8 in BALF were significantly decreased,and the concentrations of IL-10 in BALF were significantly increased at 30 min after restoration of two-lung ventilation (P＜0.05),and no significant change was found in the oxygenation index and concentrations of inflammatory factors in serum in group H (P ＞ 0.05).Conclusion Therapeutic hypercapnia can improve pneumodynamics and attenuate inflammatory responses,and has no significant difference clinically in improving oxygenation during OLV in the patients undergoing pulmonary lobectomy.
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Objective To investigate the role of protein kinase C (PKC) in reduction of hepatic ischemiareperfusion injury by CO2 preconditioning in rats.Methods Forty-eight male Wistar rats,aged 8-10 weeks,weighing 230-270 g,were randomly divided into 3 groups (n =16 each):hepatic ischemia-reperfusion injury group (group HIRI),CO2 preconditioning group (group P),and c helerythrine (CHE,a specific inhibitor of PKC) group (group CHE).The portal vein,hepatic artery and bile duct of the left lateral and median lobes of the liver were occluded for 1 h,followed by 4 h reperfusion in anesthetized rats.The rats inhaled 50％ O2-50％ N2 for 1 h during mechanical ventilation in group HIRI.In P group,the rats inhaled 50％ O2-45％ N2-5％ CO2 for 1 h during mechanical ventilation and then inhaled 50％ O2-50％ N2 and the hepatic ischemia-reperfusion injury was performed 15 min later.In group CHE,CHE 5 mg/kg was injected intraperitoneally at 10 min before mechanical ventilation,and the other procedures were similar to those previously described in P group.Before mechanical ventilation,immediately before ischemia,and at 0,1,2,3 and 4 h of reperfusion,mean arterial pressure (MAP) was recorded and arterial blood samples were obtained for blood gas analysis.At 4 h of reperfusion,the serum aspartate amino transferase (AST) and alanine amino-transferase (ALT) activities and tumor necrosis factor-α (TNF-α) concentration (by ELISA) were determined and hepatic specimens were obtained for detection of malondialdehyde (MDA) content and superoxide dismutase (SOD) activity (by spectrophotometry),and the expression of activated caspase-3 (by immuno-histochemistry) and PKC (by Western blot) in hepatic tissues.Apoptosis index was calculated by using TUNEL.Results Compared with group HIRI,MAP,PaO2 and PaCO2were significantly increased immediately before ischemia and during reperfusion in group P,MAP and PaCO2 were increased during reperfusion and PaO2 was increased immediately before ischemia and during reperfusion in group CHE,the serum ALT and AST activities,TNF-α concentrations,MDA content and apoptosis index were decreased,and the expression of activated caspase-3 was down-regulated in P and CHE groups,and the SOD activity was increased,and the expression of PKC was up-regulated in group P (P ＜ 0.05 or 0.01),and no significant changes were found in the SOD activity and PKC expression in CHE group (P ＞ 0.05).Compared with group P,MAP was significantly increased immediately after onset of reperfusion,while decreased at 1-4 h of reperfusion,PaO2 was decreased immediately before ischemia and during reperfusion,PaCO2 was decreased at 3 h of reperfusion,the serum ALT and AST activities,TNF-α concentrations,MDA content and apoptosis index were increased,and the expression of activated caspase-3 was up-regulated,and the expression of PKC was downregulated in group CHE (P ＜ 0.05).Conclusion PKC is involved in reduction of hepatic ischemia-reperfusion injury by CO2 preconditioning in rats.
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Objective To investigate the effects of dextran sulfate on lung ischemia-reperfusion injury after lung transplantation in rats.Method A total of 32 male Wistar rats were subjected to unilateral left lung orthotopic transplantation.They were randomly divided two groups (n =16 each):DXS group [DXS (10 mg/kg) was given prior to the reperfusion],and the control group (the same volume of normal saline was given).After animals were sacrificed,the lung graft was harvested 2 h after reperfusion.Oxygenation indexes,wet/dry ratio (W/D),myeloperoxidase (MPO) activity,malondialdehyde (MDA) and endothelin 1 (ET-1) in the transplanted lung,and tumor necrosis factor a (TNF-α) and interleukin 8 (IL-8) in serum were measured.The lung injury scores were evaluated and complement deposition was observed.Result After 2-h reperfusion,compared to the control group,oxygenation indexes were improved significantly in DXS group (P＜0.05),but there were no significant differences in W/D between two groups.In DXS group,the activity of MPO was significantly reduced,and the contents of MDA and ET-1 in the lung tissue were significantly reduced as compared with the control group.DXS reduced the level of TNF-α and IL-8 markedly in serum (P ＜0.05).There was no significant difference in lung injury score between two groups (4.53 ± 0.46 vs.5.28 ±0.49,P＞0.05).Compared to the control group,DXS reduced the deposition of C3c (0.8 ±0.2vs1.5±0.3) andC6 (1.2±0.4vs.2.4±0.5) (P＜0.05).Conclusion Administration of DXS attenuated ischemia-reperfusion injury after lung transplantation by inhibiting complement deposition,and improved the oxygenation of the transplanted lung.This protection was associated with inhibition of inflammation and oxidation and endothelial cytoprotection.
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Objective To investigate the effects of therapeutic hypercapnia on acute pulmonary allograft rejection induced by macrophages in rats.Methods Twenty-four adult male Wistar rats and 12 adult male Sprague-Dawley rats,weighing 250-280 g,were used in this study.The recipient rats were randomly divided into 3 groups using a random number table (n =6 each):syngraft group (group S),allograft group (group A) and therapeutic hypercapnia group (group H).In group S,Wistar rats served as donors and recipients,while in A and H groups,Sprague-Dawley rats served as donors and Wistar rats served as recipients.Orthotopic left lung transplantation was performed using the cuff technique.After transplantation,the rats inhaled 50％ N2-50％ O2 for 90 min during reperfusion in S and A groups,while in group H the rats inhaled N2-O2-CO2 for 90 min during reperfusion and PaCO2 was maintained at 80-100 mm Hg and O2 concentration in inspired air at 48％-50％ by adjusting the concentrations of the three gases.At 7 days after operation,the arterial blood sample was collected for blood gas analysis and for determination of serum concentrations of tumor necrosis factor α (TNF-α) and interferon γ (IFN-γ)by ELISA.The oxygenation index was calculated.Then the rats were sacrificed,and the transplanted lungs were removed for microscopic examination and for detection of infiltration of macrophages (by immunohistochemistry)and cell apoptosis (by using TUNEL) in lung tissues.The rejection was scored and apoptotic index was calculated.Results Compared with group S,PaCO2,serum concentrations of TNF-α and IFN-γ,rejection score,the number of macrophages and apoptotic index were significantly increased,and oxygenation index was decreased in group A (P ＜ 0.05).Compared with group A,pH value and oxygenation index were significantly increased,and serum concentrations of TNF-α and IFN-γ,rejection score,the number of macrophages and apoptotic index were decreased in group H (P ＜ 0.05).Conclusion Therapeutic hypercapnia can reduce macrophage-induced acute pulmonary allograft rejection possibly through inhibiting the inflammatory responses and cell apoptosis.
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ObjectiveTo investigate the effect of therapeutic hypercapnia on hepatic ischemia-reperfusion (I/R) injury in rat liver transplantation.MethodsMale specific pathogen-free adult Wistar rats aged 6 weeks weighing 220-280 g were used in this study.Sixteen rats in which liver transplantation was successfully performed were randomly divided into 2 groups ( n =8 each): liver transplantation group (group LT) and therapeutic hypercapnia group (group TH).In group TH,PaCO2 was maintained at 80-100 mm Hg by inhalation of CO2 for 1 h at the begining of reperfusion.MAP,PaO2 and PaCO2 was recorded during reperfusion.Blood samples were obtained at 2 h of reperfusion for determination of serum ALT,AST,TNF-α,IL-1 and IL-6 levels,and then the rats were sacrificed and transplanted liver was immediately removed for determination of NF-κB activity and apoptosis and microscopic examination.The apoptotic index was calculated.ResultsMAP,PaO2 and PaCO2 were higher,and serum ALT,AST,TNF-α,IL-1 and IL-6 levels,NF-κB activity and apoptotic index lower in group TH than in group LT ( P ＜ 0.05).The histopathologic damage was ameliorated in group TH as compared with group LT.Conclusion Therapeutic hypercapnia can attenuate hepatic I/R injury in rat liver transplantation by inhibiting inflammatory response and apoptosis.
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Objective To investigate the effects of therapeutic hypercapnia on type Ⅱ alveolar cells (ATⅡ ) in the transplanted lung in rats.Methods Twenty-eight pathogen free adult male Wistar rats weighing 180-220 g were randomly divided into 2 groups (n= 14 each) : control group (group C) and therapeutic hypercapnia group (group T). The animals were anesthetized with intraperitoneal 3% pentobarbital 30 mg/kg, tracheostomized and mechanically ventilated with 50% O2-50% N2 (VT 10 ml/kg, RR 60 bpm, I∶ E1∶1). Left lung transplantation was performed. In group T starting from the beginning of reperiusion of the transplanted lung, the animals were ventilated with a mixture of 50% O2-N2 and C02(in appropriate concentrations) to keep PaCO2 between 80-100 mm Hg. After 90 min of reperfusion of the transplanted lung, blood samples were collected from pulmonary vein of the transplanted lung and blood gas analysis was performed. Oxygenation index was calculated.AT II cells were isolated from the transplanted lung and purified and examined with electronic microscope. The apoptosis rate of AT Ⅱ cells was detected by flow cytometry. Results Oxygenation index was significantly higher, the apoptotic rate of ATⅡ cells lower, the damage to ATⅡ cells was less in group T than in group C.Conclusion Therapeutic hypercapnia can protect the AT Ⅱ cells in the transplanted lung and improve the function of the trans planted lung.
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Objectlve To investigate the effects of different ventilation modes on the efficacy of exogenous pulmonary surfactant(PS)for the treatment of rats with ventilator-induced lung injury(VILI).Methods Forty-two male Wistar rats weighing 310-356 g were randomly divided into 6 groups(n=7 each):group CVT6,group SVT6,group CVT10,group SVT10,group CVT14 and group SVT14.The tidal volume(VT)was set at 6,10 and 14 ml/kg respectively and the respiratory rate(RR) was 75,45 and 32 bpm respectively.The animals were anesthetized with intraperitoneal 3% Pentobarbital 50 mg/kg,then tracheostomized and intubated.VILI model was induced by high-pressure ventilation (HPV) with peak inspimtory pressure (PIP) 40 cm H2O and without positive end-expiratory pressure (PEEP).The air was injected into the trachea via the airway at the end ofexpiration before HPV (T0,baseline value) and 15-25 min of HPV,the airway pressure monitored and the lung compliance(C) calculated.When C was decreased to half of the baseline value,PEEP was increased to 7.5 cm H20.After the tracheal edema fluid was removed,the PS 100 mg/kg was immediately injected into the trachea in group SVT6,SVT10 and SVT14.The equal volume of air was injected into the trachea in group CVT6,CVT10 and CVr14 instead of PS.Then the rats in different groups were ventilated with the corresponding ventilation modes.MAP was monitored and blood samples were token from femoral artery for blood gas analysis at T0, 5 min after HPV (T1 ), and 15, 30, 60, 90, 120 min (T2-6) after administration of PS. The tracheal edema fluid was collected at T1 and T6.The rats were killed at T6 and the lung tissues taken for microscopic examination. Results With the same ventilation mode, the VILI was significantly alleviated after administration of PS. With different ventilation modes,the lung injury was significantly reduced in group SVT 10 compared with the other groups. Conclusion The efficacy of PS for the treatment of rats with VILI is good using the ventilation strategy with VT of 10 ml/kg and RR of 45 bpm.
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Objective To investigate the effect of sodium citrate on the efficacy of oral midazolam premedication in children with congenital heart disease. Methods Forty ASA Ⅱ or Ⅲ children, aged 2-6 yr, weighing 12-20 kg, undergoing cardiac surgery, were randomly divided into 2 groups (n = 20 each): control group (gronp C) and sodium citrate group (group S). Group S received oral mixture of midazolam 0.12 ml/kg (0.6 my/kg), ketamine 0.12 ml/kg (6 my/kg), glucose 0.12 ml/kg (60 mg/kg) and sodium citrate 0.12 ml/kg (3 mg/kg), total volume 0.48 ml/kg. Group C received oral mixture of midazolam 0.12 ml/kg, ketamine 0.12 ml/kg and glucose 0.24 ml/kg, total volume 0.48 ml/kg. Hydrochloric acid (pH value 1.75) was mixed with the mixtures in the two groups and pH values were measured. Preoperative anxiety scale and the onset time,sedation score and parental separation score after receiving oral drugs were recorded in preparation room for anesthesia. After entering the operating room, HR, MAP and SpO2 were monitored, and the response to venepuncture in children and the adverse effects associated with oral drugs were also observed and recorded. Results The pH value was 1.97 in group C and 4.52 in group S. The parental separation score, sedation score and response score were significantly lower and the onset time was significantly shorter in group S than in group C. HR, MAP and SpO2 were in the normal range after entering the operating room. There was no obvious adverse effect after administration of oral drugs in the two groups. Conclusion Application of sodium citrate in the oral premedication in children with congenital heart disease can raise the pH value, shorten the onset time of midazolam, and enhance the sedative efficacy.
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Objective T Iymphocytes were considered to be activated and involved in the ischemia-reperfusion injury during lung transplantation.Carbon dioxide pneumoperitoneum was shown to have inhibitory activity on the immune system.This study was designed to_investigate the effects of the effects of the therapeutic hypercapnia on the T Iymphocytes of rats in which ischemia-reperfusion injury occurred during lung transplantation.Melhods Sixteen Wismr rats weighed 300 to 400 g were randomized into control group(8 rats) or therapeutic group (8 ras)after transplantaion.Animals in both grotups were Oven inluded nitrogen(50%)and oxygen N2+(50%) at baseline. Animats in the control groap were given irked nitrogen (50%)and oxygen(50%)throughout the experiment ,and that in the thera-peutic group were given mixed gas which was composed of nitroged(40%),oxygen(60%)and carbon dioxide in appropriate concentra-tion to keep arterial partial pressure of carbon dioxide (PaCO2)at 80-100 mm Hg and FiO2 at 50%after reperfusion.All of the ani-mals were observed for 90 minutes after reperfusion.Mean arterial pressure(MAP) and arterila partial pressure of oxygen(PaO2) were recorded at baseline and every 15 minutes during the period of reperfusion.The expression of CD3,CD4 and CD28 in the peripheral blood was,examined,and the concentrations of Ifn-у,IL-2,IL-4 and IL-1O in the homogenate were measured after the experiment. Histological analysis of samples from transplanted lungs was performed.Resykts After reoerfysion,MAP and PaO2 in the therapeutic group were higher signitleantly than that in the group(P<O.05).The expression of CD3,CD4 and CI)28 in the perioheral blood,mid the concentrations of IL-2 and IFN-y in the homogenate higher sinificantly in the group than that in the thera- peutic group (for all comparisons,P<O.05).IL-4 was decreased in the control group as compared with the therapeutic group(P<0.05).No sigllificant difference for IL-IO was observed between two groups.Histological study revealed that the haemorrhage and edema were obviously alleviated in the therapeutic group.Conclusion Therapeutic lypercapnia may have inhibitory effects on the T Iymppho- cytes in rats receiving lung transplantation.This treatment decreaseed the number of T lymphocytes in the peripheral blood and the expres-sion of CD28,as well as IL-2 and IFN-y secreted by the Thl cells,and facukutated IL-4 production by Th2 cells.
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Objective To investigate the effect of therapeutic hypercapnia on the inflammatory response in the rat lung transplantation. Methods Male pathogen free Wistar rats weighing 300-400 g were used in this study. The animals were anesthetized with 3% pentobarbital sodium 30 mg/kg, tracheostomized and mechanically ventilated (V_T 10 ml/kg, RR 50 bpm, FiO_2 50%). Carotid artery and femoral vein were cannulated for BP monitoring, blood sampling and fluid and drug administration. Left lung transplantation was performed using modified cuff technique. Forty-eight animals in which lung transplantation was successfully performed were randomized into 2 groups ( n = 24 each) : model group (M) and hypercapnia group (H) . In group H, PaCO_2 was maintained at 80-100 mm Hg by inhalation of CO_2.Arterial blood samples were obtained before lung transplantation (To , baseline) and at 1, 2, 4 h (T_(1-3)) of reperfusion for determination of blood TNF-α, IL-1 and IL-8 concentrations. The animals were then killed and the transplanted lungs were removed for microscopic examination and calculation of wet/dry lung weight ratio. Results The MAP and PaO_2 were significantly higher in group H than in group M. The blood IL-8 and TNF-α concentrations were significantly lower at T_(1-3) in group H than in group M, but there was no significant difference in blood IL-1 concentration between the 2 groups. The elastase content in the lung tissue was significantly lower at T_2 and T_3 in group H than in group M. Microscopic examination showed that the alveolar hemorrhage, the infiltration of the lung by macrophages and neutrophils and lung edema were significantly less in group H than in group M. Conclusion Therapeutic hypercapnia can obviously inhibit the inflammatory response in the rat lung transplantation.
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This paper reviewed the classification of hemp,distinction between industrial hemp and marijuana hemp,and the use value of industrial hemp.Some research problems and future research trends were also discussed.
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Objective To investigate the effects of lung lavage on respiratory function of experimental silicosis.Methods Thirty rats were randomly divided into three group: A, B and C. An intratracheal injection of 50 mg silica in 1 ml of sterile saline was given in group A and B, and in group C the same amount of normal saline was injected into trachea following the anesthesia with ether. Fifteen days later, the animals were anesthetized with an intraperitoneal injection of pentobarbital sodium 30 mg/kg. After endotracheal intubation through a trachotomy, three animals were connected in parallel to a pressure controlled ventilator. The respiratory frequency was set at 28 bpm with a 50% inspiration time, and 100% oxygen was used as the inspiratory gas. Throughout the experiment, the peak inspiratory pressure (PIP) was fixed at 2.45 kPa (25 cm H 2O) and the end expiratory pressure (PEEP) at 0.69 kPa (7.0 cm H 2O). Group A and C was lavaged 10 times respectively and group B was lavaged 20 times. Arterial blood gases, tidal volume, pressure volume and lung lavage fluid constituents were assessed. Results Arterial partial pressure of oxygen (PaO 2 ) in group C was higher than that in group A and B before lavage, increased significantly in group A and decreased significantly in group B and C after lavage, but arterial partial pressure of carbon dioxide (PaCO 2 ) rose gradually in group B and C . The vary amount of PaO 2 and PaCO 2 of group C was more significant than of group B. Tidal volume in group C was higher than that in group A and B before lavage, decreased significantly after lavage in group B and C. There were significant differences among three groups in pressure volume ratio. Protein concentrations in lung lavage fluid of group A and B were much higher than of group C, but phospholipid concentrations in lung lavage fluid had no different.Conclusions Lung lavage can improve respiratory function of early experimental silicosis. Unsuitable lavage may cause respiratory dysfunction.