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.
To investigate the effect of intracellular glycogen on liver ischemia-reperfusion and its mechanism, histomorphological and enzymological changes, histic ATP contents, the activity of Ca2+-ATPase on cytoplasmic membrane and intracellular free Ca2+concentration were observed during the ischemia-reperfusion of three groups of rabbit livers with different glycogen content. We found that the more vigorous energy metabolism, the higher activity of Ca2+-ATPase, the lower concentration of intracellular free Ca2+ and the slighter injury of histic structure and function appeared in the liver with the more abundant glycogen. The results suggest that intracellular abundant glycogen may reduce liver ischemiareperfusion injury.
ObjectiveTo review the recent research progress about the pathogenesis and prevention of reactive oxygen species (ROS) in the hepatic ischemia-reperfusion injury (HIRI). MethodsSearched the related literatures in recent years from the databases such as CNKI, PubMed and so on, summarized the recent research progress about the generation mechanism of ROS, the damage mechanism of ROS, and the prevention method of ROS. ResultsA mass of ROS originated from polymorphonuclear leukocytes, Kupffer cells, mitochondria, and the enzymes in hepatic tissue in HIRI. It mainly destroyed sugar molecules of oligosaccharide chains on the cell membrane, unsaturated fatty acid, protein molecules, mitochondrial, and genetic material. This mechanism lead to cell injuried or even death. The main method of prevention and cure to HIRI is eliminating ROS by using enzymes, vitamins, Chinese herbal medicines etc. ConclusionsThe research about ROS in HIRI has advanced. Aiming at the damage resulted from ROS in the liver, Scholars have came up with a variety of control methods which is feasible. However, many issues need to be further investigated.
【Abstract】Objective To study the protective effects of anisodamine on liver ischemia-reperfusion injury in rats. Methods One hundred and sixty male Wistar rats were randomly divided into the normal control (n=10), ischemiareperfusion (n=50), normal saline (n=50) and anisodamine (n=50, 2.0 mg/kg) groups. The animals were killed 1, 3, 6, 12, 24 hours after ischemia induced for 60 minutes and followed by reperfusion. Plasma endothelin-1 (ET-1), hyaluronic acid (HA), glutamic-pyruvic transaminase enzyme (ALT) were measured, and the hepatic histopathologic alterations were also observed. Results The plasma ET-1, HA and ALT concentrations were markedly increased after liver ischemiareperfusion.The hepatic congestion was significantly obvious. An intravenous injection of anisodamine before ischemiareperfusion could decrease the plasma HA and ALT concentrations and relieve the hepatic congestion. Conclusion Anisodamine can improve hepatic microcirculatory disturbances after reperfusion and have hepatoprotictive effects on rat liver ischemia-reperfusion injury.
【Abstract】 Objective To study the effects of ischemic preconditioning (IP) on the activity of nuclear factor-κB （NF-κB） and the expressions of TNF-α and intercellular adhesion molecule-1 (ICAM-1) during early reperfusion following liver transplantation in rats. Methods The models of rat orthotopic liver transplantation were established. The donor livers were stored for 2 hours in Ringers solution at 4 ℃ before transplantation. All rats were randomly divided into sham operation group （SO group）， control group and IP group. IP group was achieved by clamping the portal vein and hepatic artery of donor liver for 10 minutes followed by reperfusion for 10 minutes before harvesting. The activity of NF-κB and expressions of TNF-α and ICAM-1 at 1 h, 2 h, 4 h and 6 h after reperfusion were measured. Serum ALT, LDH were also determined. Results The liver function of recipients with IP were significantly improved. Compared with SO group， the graft NF-κB activity increased after transplantation in control group and IP group (P＜0.05), while compared with control group that was significantly attenuated at 1 h and 2 h in IP group. Similarly, hepatic levels of TNF-α and ICAM-1 were significantly elevated in control group and were reduced in IP group. Conclusion IP might down-regulated TNF-α and ICAM-1 expression in the grafts after orthotopic liver transplantation through depressed NF-κB activation， and attenuate neutrophil infiltration in the grafts after reperfusion.
【Abstract】ObjectiveOn the basis of traditional transplantation model, a successful model of pancreaticoduodenal transplantation (PDT) were established in rats, which is the foundation of basic and clinical transplantation research. Methods We improved the technique of microoperation on donor and harvested high-quality graft. The dual cuff technique was applied to end-to-end anastomose proximal part of abdominal aorta and portal vein with left renal aorta and vein of recipient, and distal part of abdominal aorta was connected with Y-tube. External secretion was performed by duodenum stoma. The PDT model was finished without blocking systemic circulation and portal vein system. Random blood glucose levels and drainage were monitored postoperatively to evaluate the function of endocrine and ectocrine. Results Thirty operations were done. The total procedure of transplantation lasted 2 hours. Moreover the operation on recipient and the reconstruction of vessels took only (26±5) and (25±5) minutes, respectively. The success rate was elevated to 100%. The ectocrine function was restored within 2 hours after operation. Except for 3 cases of non-function graft because of thrombosis in cannula, the glucose level of the remaining recipients was reduced to normal level 6 h or 24 h after transplantation. The survival rate of graft function was 90% (27/30). Conclusion This model is finished without special equipment and can recover the endocrine function in advance. It is a simple and stable model, which might be used in research of the theoretical problems involved in clinical pancreas transplantation.
Objective To study the effect of p38MAPK activity on tumor necrosis factor-α （TNF-α） mRNA and intercellular adhesion molecule 1 （ICAM1） mRNA expressions of isolated rabbit liver during early stage of cold preservation and reperfusion period. Methods Based on the cold preservation and reperfusion model of isolated rabbit liver, the animals were divided into inhibition group （n=12） with 3 μmol/L SB202190 (p38MAPK specificity inhibitor) in perfusate and control group （n=12） with no SB202190 in perfusate. Liver tissue samples were harvested at the time points of before resection, end of cold preservation, and different reperfusion period (10, 30, 60 and 120 min). Protein expression and activity of p38MAPK were detected by Western blot and immunoprecipitation respectively, expression of TNF-α mRNA was detected by RT-PCR, and expression of ICAM1 mRNA was detected by in situ hybridization. Results There was no obvious change of expression of p38MAPK protein in liver tissue both in two groups during the total period （P＞0.05）， and there was no statistically significant difference between two groups （P＞0.05）. At time points of end of cold preservation, 10, 30 and 60 min of reperfusion, the activity of p38MAPK in control group was significantly higher than that at the time points of before resection and 120 min of reperfusion (P＜0.01), and was also significantly higher than that in inhibition group at the same time points (P＜0.01). There was no significant difference in activity of p38MAPK among all time points in inhibition group (P＞0.05). The expressions of TNF-α mRNA and ICAM1 mRNA at the time points of before resection, end of cold preservation, and 10 and 30 min of reperfusion were significantly lower than those in 60 and 120 min of reperfusion in both two groups (P＜0.05, P＜0.01); The expressions of TNF-α mRNA and ICAM1 mRNA in inhibition group were significantly lower than those in control group at the time points of 60 and 120 min of reperfusion (P＜0.01). The activity of p38MAPK of liver tissue during cold preservation and reperfusion period was significantly correlated with the level of TNF-α mRNA and level of ICAM1 mRNA expression （r=0.996, P＜0.01； r=0.985, P＜0.01）. Conclusions These results suggest that p38MAPK pathway may regulate the expressions of TNF-α and ICAM1 at the level of transcription and the activation of p38MAPK can up-regulate TNF-α and ICAM1 expressions, which may be one of the important mechanisms to cause ischemia-reperfusion injury of isolated liver during cold preservation and reperfusion period.
Adenosine triphophate (ATP), substantially liberated from the injured cells, activates the inflammatory cells to secrete various inflammatory factors, thus triggering uncontrolled systemic inflammatory response and thrombosis with aggravating the degree of damage. Metabolic pathway of adenosine consists of adenosine (Ado) synthase CD39-CD73, nucleoside transporters (NTs) and termination system of adenosine deaminase (ADA) and adenosine kinase (ADK). As a " switch” of the inflammatory response, the metabolic pathway converts ATP (the pro-inflammatory cytokines) to Ado (the anti-inflammatory mediators), maintaining the homeostasis between pro-inflammatory and anti-inflammatory as well as affecting the outcome of the injury. This review focused on the recent progress of adenosine metabolic pathway in cell injury.
Objective To investigate the effects of adenosine 2A receptor (A2AR) activation on oxidative stress in small-forsize liver transplantation. Methods A rat orthotopic liver transplantation model was performed using 40% graft, 18 recipients were given intravenously saline (control group), CGS21680 (A2AR agonist, CGS21680 group) or ZM241385 (A2AR antagonist, CGS21680+ZM241385 group) randomly. Aspartate aminotransferase (AST), enzymatic antioxidants 〔superoxide dismutase (SOD); catalase (CAT); glutathione peroxidase (GSH-Px)〕, non-enzymatic antioxidants 〔ascorbic acid (AA); glutathione (GSH); α-tocopherol (TOC)〕 and lipid oxidant metabolites malondialdehyde (MDA) were measured and analyzed at 6 h after reperfusion. Results Compared with the control group and CGS21680+ZM241385 group, A2AR activation increased the activities of SOD and GSHPx (Plt;0.05), reduced the productions of AST and MDA (Plt;0.05), increased the levels of AA, GSH and TOC (Plt;0.05) in CGS21680 group. But there was no significant change in CAT activity (Pgt;0.05) among 3 groups. Conclusions A2AR activation improves the antioxidant enzyme activities, promotes the production of antioxidants, and slowes down the increase in MDA level, depresses of the increase in AST activity. A2AR activation suppresses oxidative damage and increases the antioxidant capacity which in turn minimizes their harmful effects of ischemia-reperfusion in small-for-size liver transplantation.
Objective To investigate the protective effects of liposome prostaglandin E1（Lipo-PGE1） on myocardial ischemia-reperfusion injury （MIRI） during cardiopulmonary bypass （CPB）. Methods Thirty-two patients with clearly diagnosed heart valve disease and congenital heart disease such as atria septal defect （ASD） and ventricular septal defect （VSD） were selected in our hospital. The patients were randomly divided into two groups （16 patients in each group）, Lipo-PGE1 group： Lipo-PGE1（2ng/kg·min） was continuously pumped before starting of CPB until 2 h after ascending aortic off-clamping; control group： using the same volume of normal saline, arterial blood samples were taken before CPB, at 1, 2, 6 and 24 h after the ascending aortic off-clamping. The value of cardiac troponin I （cTnI）, creatine kinase MBmass （CK-MB）, interleukin-6 （IL-6）, tumour necrosis factor-α （TNF-α）, intercellular adhesion molecule-l（sICAM-1） were measured. Results cTnI, CK-MB, IL-6, TNF-α and sICAM-1 showed no significant difference in the two groups before CPB （P〉0. 05）. At 1,2, 6 and 24h after ascending aortic off-clamping, those values rose significantly than before CPB（P〈0. 01）, but Lipo-PGE1 group＇s values were lower than those in the control group （P〈0. 05）. Conclusions Lipo-PGE1 （2ng/kg·min） continuously pumped from before CPB to 2h after ascending aortic off-clamping can inhibit effectively the production of IL-6, TNF-α, and reduce the expression of sICAM-1, attenuate the process of inflammation, lighten the injuries of myocardial cells, and effectively protect the MIRI during CPB open heart surgeries.