ObjectiveTo study the changes of levels of α subunits of stimulatory (Gsα) and inhibitory guanine nucleotide binding protein (Giα) in newborn guinea pig (0 2 days old) myocardium undergoing global ischemic reperfusion, and influences on the changes by St.Thomas Ⅱ and cold blood cardioplegic solution.MethodsThirty newborn guinea pigs were randomly assigned to three groups. GroupⅠ ( n = 10): the newborn hearts suffered by hypothermic global ischemia; group Ⅱ( n =10): the newborn hearts arrested by St. Thomas Ⅱ , and group Ⅲ ( n = 10): the newborn hearts arrested by cold blood cardioplegic solution. Levels of Gsα and Giα were investigated with Western blot analysis.ResultsNo differences of levels of Gsα and Giα were found in three groups before ischemia ( P gt;0.05). The level of Gsα after ischemia was significantly decreased than before ischemia in groupⅠand group Ⅱ ( P lt; 0 01), whereas no pronounced changes in group Ⅲ ( P gt;0.05) were noted after ischemia. The level of Gsα in group Ⅲ was not significantly changed after reperfusion compared with before ischemia( P gt;0 05), and it was much higher than those in groupⅠand group Ⅱ ( P lt; 0 01). Level of Giα was found not markedly changed in group Ⅲ after reperfusion compared with that before ischemia, but was notable higher in groupⅠand group Ⅱ( P lt;0.01). ConclusionsSignificant decrease of level of Gsα, whereas marked increase of level of Giα are found in myocardium of newborn guinea pig undergoing hypothermic (20℃) ischemic reperfusion. No impact of St. Thomas Ⅱ on these changes is verified, but recovery to the level of Gsα and Giα before ischemia is achieved by cold blood cardioplegic solution after ischemia and reperfusion. Unbalance between Gsα and Giα is the one of the mechanisms of ischemic reperfusion injury for immature myocardium.
目的 探讨异氟醚通过抑制细胞间黏附分子（ICAM-1）表达参与减轻肝脏缺血-再灌注（IR）损伤的可能调节机制。 方法 32只雌性SD大鼠分为4组。A组大鼠行腹腔注射1%戊巴比妥钠40 mg/kg麻醉，进行手术但不阻断入肝血流；B组1%戊巴比妥钠麻醉后行部分肝脏IR；C组大鼠仅接受1.0 MAC异氟醚吸入麻醉，不阻断血流；D组采用1.0 MAC异氟醚麻醉，建立肝脏IR模型。肝脏缺血60 min，再灌注3 h后取肝组织和血液标本，检测血清丙氨酸转氨酶（ALT）和天冬门氨酸转氨酶（AST）、肝组织ICAM-1和肝组织还原型谷胱甘肽（GSH）、脂质过氧化物丙二醛（MDA）和超氧化物歧化酶（SOD）含量。 结果 与戊巴比妥钠麻醉比较，采用异氟醚处理后明显降低血清ALT和AST的水平，再灌注肝组织内GSH、SOD含量明显高于而MDA含量降低，同时抑制肝组织ICAM-1的表达。 结论 异氟醚麻醉能够有效减轻肝脏IR损伤，抑制氧自由基的生成和释放，具体机制可能与抑制ICAM-1表达致使细胞内GSH含量增加密切相关。
ObjectiveTo summarize the research progress of severed limb preservation by perfusion and to analyze difference in effect of severed limb preservation by different perfusate. MethodsThe domestic and foreign related literature about severed limb preservation by perfusion was extensively reviewed and analyzed. ResultsCurrently the main perfusate includes organ perfusate,free radical scavengers,energy mixture,blood substitutes,and whole blood.They can reduce the skeletal muscle's ischemia-reperfusion injury in different degrees. ConclusionDifferent perfusate can reduce the skeletal muscle's ischemia-reperfusion injury in different degrees,but the best effect of perfusate and personalized preservation method need further study.
Objective To study the mechanisms and treatment of ischemia /reperfusion injury, expression of intracellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) were measured, the effect on suppression of ICAM-1 and VCAM-1 by the pyrrolidine dithiocarbamate (PDTC) were investigated. Methods Endothelial cells were divided into 3 groups, hypoxia group: endothelial cells were exposed in hypoxia condition, then returned to reoxygenation condition; the PDTC group: PDTC was added to the endothelial cells in the culture media before exposing to hypoxia condition; control group: endothelial cells underwent treatment. Confocal microscopy was used to detect expression of ICAM-1 and VCAM-1. Results ICAM-1 and VCAM-1 expression were low in endothelial cells of control group, and increased in hypoxia group . ICAM-1 and VCAM-1 expression of endothelial cells in PDTC group werelower than those in hypoxia group , but higher than those in control group. Conclusions It seems that hypoxia/ reoxygenation can activate the endothelial cells and increase the expression of cell adhesion molecules. PDTC can decrease the expression of ICAM-1 and VCAM-1. PDTC may prove benificial in the treatment of ischemia /reperfusion injury.
ObjectiveTo study the protective effects of ischemia preconditioning (IPC) on cryopreservation injury of rat liver.MethodsThe model of isolated nonrecirculated perfusion rat liver was established. The grafts were treated with IPC in different time (ischemia preconditioning time in IPC1 group was 5 min; the time in IPC2 group was 10 min; while the time in IPC3 group was 15 min). The cryopreservation injury of the grafts in each group was determined and compared. ResultsThe levels of aspartate transaminase (AST) and alanine transaminase (ALT) in the effluent solutions in IPC1 group were (40.1±6.3) U/L and （17.1±0.5） U/L respectively, and IPC2 group (53.6±3.7) U/L, （19.7±0.5） U/L, which were much lower than those of nonpreconditioning (NPC) group 〔(64.5±8.2) U/L, （23.8±3.9） U/L〕 (P＜0.05). Those in IPC1 group was much lower than those in IPC2 group and IPC3 group 〔(63.8±7.2) U/L,（22.8±2.5） U/L〕 (P＜0.05). The level of lactic acid dehydrogenase (LDH) in NPC group (104.3±20.6) U/L, IPC1 group (84.1±19.7) U/L, IPC2 group (90.5±21.1) U/L, and IPC3 group (103.1±18.5) U/L were of no significant difference (Pgt;0.05). The contents of bile product and the hepatocellular contents of ATP in IPC1 group were (53.5±10.2) μl and (6.15±0.65) μmol/g respectively, and IPC2 group (41.5±8.1) μl, (4.77±0.21) μmol/g, which were much higher than those NPC group 〔(22.8±9.7) μl, (2.62±0.34) μmol/g〕 (P＜0.05). Those in IPC1 group were much higher than those in IPC2 group and IPC3 group 〔(27.5±2.8) μl, (2.61±0.29) μmol/g〕 (P＜0.05). The contents of malondialdehyde (MDA) in liver tissue in IPC1 group was (4.36±0.26) nmol/gand IPC2 group (5.51±0.13)
Objective To investigate the maximum tolerance limit of rats to hepatic inflow occlusion with portal vein blood bypss (PBB) in normothermia. Methods First. A new animal model was established, the animal survival rate were calculated following 7 days of reperfusion after hepatic inflow occlusion of 30, 60, 90, 100, 110, 120 min or portal triad clamping (PTC) of 30 min. And then, the hepatic energy metabolism (RCR, P/O, ATP, AKBR) was studied following 30, 90, 120 min of ischemia or 1, 6, and 24 hours of reperfusion after the ischemia. According to the reversibility of the hepatic motochondrial function injury and maximum as long as a period of liver warm ischemia of all animal postoperative 7 days survial, the safe limit of rat to hepatic inflow occlusion was evaluated. Results The survival rate on postoperative 7 days was one hundred percent subjected to 30, 60 and 90 min of hepatic inflow occlusion, and 50, 30, 20 percent in 100, 110, 120 min, respectively, the survival rate in rats with 30 min of portal triad champing was about 40 percent. The parameters of hepatic motochondrial function reflecting the degree of liver damage to ischemia showed significantly different as compared to sham group. The functional lesion was exacerbated during inital reperfusion, then was restored progressively in PBB-30 min and PBB-90 min groups, but was maintained low level in PBB-120 min and PTC-30 min groups.Conclusion The 90 minutes is the maximum limit of rats to hepatic inflow occlusion in normothermia.
【Abstract】Objective The injury induced by hepatic artery ischemia (HAI) in the liver transplantation procedure and the protective effects of using hepatic artery bridge-conduit (HABC) technique were studied. Methods Thirtytwo dogs were randomly divided into 4 groups: control, HAI 30 min, HAI 2 h and HABC groups. We observed the pathological changes of hepatocytes and biliary tract tissues and the microstructure of chondriosome, which were based on the model of auto-orthotopic liver transplantation in dogs. Biochemical and spectrophotometric methodswere used to evaluate the content of MDA and SOD, SDH activities in the graft liver tissue respectively. Results The pathologic and electrical microscopic changes of hepatocytes and epithelial cells of bile ducts were found in HAI 30 min and HAI 2 h groups,while the content of MDA increased to （1.652±0.222） nmol/mg prot and (2.379±0.526) nmol/mg prot, and SOD activity decreased to (11.15±3.9) U/mg prot and (9.47±3.4) U/mg prot. At the same time, SDH activity was also down-regulated to 0.362±0.019 and 0.281±0.029. Compared with control group, the differences were significant (Plt;0.05, Plt;0.01). But these changes of functional index caused by HAI injury were not significant in HABC group. Conclusion The HABC technique can not only avoid HAI injury during operation but also alleviate the occurrence of complication after transplantation, especially the biliary tract complication.
【 Abstract 】 Objective To investigate the protective effect of peroxisome proliferator-activated receptor γ (PPAR γ ) activator 15-deoxyprostaglandin J2 (15d-PGJ2) in rat hepatic ischemia-reperfusion injury and its mechanism. Methods The models of 70% warm ischemia-reperfusion injury were established in SD rats, rats were randomly divided into 4 groups: sham operation group, ischemia-reperfusion group, 15d-PGJ2 group and 15d-PGJ2+GW9662 group. After reperfusion, serum AST and ALT levels were determined; the liver tissues were removed for measurement of activity of NF-κB and myeloperoxidase (MPO), TNF-α content and expression of ICAM-1. Results Compared with sham operation group, the serum levels of ALT and AST, and the activities of MPO and NF- κ B, TNF- α content and expression of ICAM-1 in ischemia-reperfusion group, 15d-PGJ2 group and 15d-PGJ2+GW9662 group were greatly improved (P ＜ 0.05). Compared with ischemia-reperfusion group, the serum levels of ALT and AST and the activities of MPO and NF- κ B, TNF- α content and expression of ICAM-1 in 15d-PGJ2 group were significantly decreased (P ＜ 0.05). Compared with 15d-PGJ2 group, the serum levels of ALT and AST, and the activities of MPO and NF- κ B, TNF- α content and the expression of ICAM-1 in 15d-PGJ2+GW9662 group were obviously increased (P ＜ 0.05). Conclusion PPAR γ activator 15d-PGJ2 could protect against ischemia-reperfusion injury in rats, with its possible mechanism of inhibiting NF-κB activation and down-regulating TNF-α content and ICAM-1 expression in a PPARγ dependent fashion.
【Abstract】ObjectiveTo investigate the effect of ischemia-reperfusion （I/R） injury on apoptosis of pancreatic cells in rats with acute pancreatitis(AP). MethodsFifty-four SD rats were randomized into 3 groups: pancreatitis group (n=24), I/R-injury group (n=24) and control group (n=6). The animal model of AP was induced by retrograde injection of 3% sodium taurocholate into biliopancreatic duct in rats. Pancreatic I/R was caused by blocking the inferior splenic artery and removing the clamp after AP induction. At 1 h, 3 h, 6 h and 12 h, groups of rats were sacrificed. A terminal deoxynucleotidyl transferase-mediated dUTP-biotion nick end labeling (TUNEL) was used to detect pancreatic apoptosis, and histological changes of the pancreas were observed. ResultsPancreatic hemorrhage, necrosis were respectively observed in the pancreatitis rats at 6 h and the I/R-injury rats at 1 h. Histological changes of the pancreatitis rats at 1 h and 3 h were only congestion and edema. Apoptoic acinar cells increased after AP induction, the peak respectively appeared at 6 h in the pancreatitis rats and at 3 h in the I/R-injury rats. Compared with the pancreatitis rats, apoptosis index (AI) of the I/Rinjury rats was significantly higher at 1 h and 3 h (P＜0.01, P＜0.05, respectively), but lower at 6 h and 12 h (P＜0.05, P＜0.01, respectively). ConclusionI/R injury can induce conversion of edematous pancreatitis to hemorrhagic necrotizing pancreatitis and apoptosis of acinar cells. Apoptosis may be a beneficial response to pancreatic injury in AP.
Objective To examine the effect of endothelial progenitor cell (EPC) on lung ischemia-reperfusion injury (LIRI). Methods Twenty-four recipients were randomized into 3 groups including a sham group, a LIRI group, and an EPC group. Rats in the sham group only received anesthesia. Rats in the LIRI and EPC groups received left lung transplantation and received saline or EPC immediately after reperfusion. The partial pressure of oxygen to fraction of inspiratory oxygen (PaO2/FiO2) ratio, wet-to-dry weight ratio and protein levels in the transplanted lung and inflammation-related factors levels in serum were examined. Histological change of transplanted lung were analyzed. The nuclear factor (NF)-κB in the transplanted lung was detected. Results Compared with the LIRI group, the PaO2/FiO2 ratio dramaticly increased, and the wet-to-dry weight ratio and protein level significantly decreased by EPC after reperfusion. The lung histological injury was attenuated by EPC. The pro-inflammatory factors in serum were down-regulated, whereas IL-10 was up-regulated in the EPC group. The expression of NF-κB was decreased by EPC. Conclusion EPC ameliorated LIRI after lung transplantation. The protection of EPC partly associated with anti-inflammation.