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.
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.
Objective To study the efect of IH764-3 on ischemia-reperfusion (I/R) injury in rat liver. Methods Rats were divided into 3 groups, the control group was not subjected to ischemia and no treatment was given. I/R injury group was subjected to 40 minutes ischemia followed by reperfusion for 120 minutes. The IH7643 group (40mg/kg) was administred at ischemia and reperfusion. Results In the IH764-3 group, sereum levels of ALT, AST, AKP and γ-GT were significantly lower than those in the I/R group. Energy charge level recovery was significantly higher with IH7643 (P＜0.05), hepatic ultrastructure was better preserved with IH764-3. Conclusion IH764-3 may be useful in the treatment of hepatic ischemia reperfusion injury
Objective To observe the protective role of the ectogenesis zinc on the cells in rat flap with ischemia reperfusion injury and study the mechanisms. Methods A right low abdominal island flap was created in Wistar rats. Fortyeight rats were randomly divded into 3 groups (n=16):the control group, the ischemia reperfusion group and adding zinc ischemia reperfusion group.The content of malondialdehyde(MDA) and the activity of myeloperoxidase(MPO) were measured by thiobarbituric acid methods and colorimetry. The location of expression of MT was observed,and the image analysis was performed. The quantity of MT was represented by the integratial optical density. The ultrastructure changes of skin flap with ischemia reperfusion injury and the flap viability were observed. Results In the ischemia reperfusion injury flaps, the content of MDA and MPO show no statistically significant difference among the control group,IR group and the adding-zinc-IR group (P＞0.05). Compared with the control group at 1 h and 24 h of reperfusion, the level of MDA increased 62.2% and 136.4%(P＜0.01) in the IR group, which increased 11.3% and 33.2%(P＜0.01) in the adding-zinc-IR group. The activity of MPO increased 238.4% and 503.4%(P＜0.01)in the IR group when compared with the control group, and increased 17.9%and 24.1%(P＜0.05) when compared with the adding-zinc-IR group. In the ischemia reperfusion injury falps, the content of MT in the control group and the IR group is too minimal to measure. While the content ofMT in the adding-zinc-IR group is 45.30±7.60. At 1 h and 24 h of reperfusiion, the content of MT in the adding-zinc-IR group increased 41.5% and 44.9% (P＜0.01) compared with the IR group, and increased 119.9% and 234.6% (P＜0.01) compared with the control group. The flap viability is 100% in the control group, 19.65%±4.38% in the IR group, and 24.99%±5.12% in the adding-zinc-IR group, which increased 27.2% (P＜0.05) compared with IR group. Conclusion Many kinds of cells in skin flap with ischemiareperfusion injury can be protected by ectogenesis zinc and the flap viability increases significantly.
目的 探讨大鼠离体肝脏保存再灌注后肝脏组织中细胞间黏附分子-1（ICAM-1） mRNA的表达变化及丹参对其表达的影响。 方法 选取健康Wistar雄性大鼠54只，用完全随机方法选6只大鼠作为正常组，切除肝脏后立即灌注；随机选24只大鼠作为对照组，切除肝脏后置入4 ℃UW液中分别保存8、16、24、32h后再行肝脏循环再灌注；余下的24只作为实验组，切除肝脏后置入含丹参的4 ℃UW液中分别保存8、16、24、32h后再行肝脏循环再灌注。应用 RT-PCR方法检测各组大鼠离体肝脏保存再灌注后肝脏组织中ICAM-1mRNA表达。 结果 正常组肝脏中的ICAM-1mRNA表达为3.61±1.56，对照组和实验组8、16、24、32h时肝脏中ICAM-1mRNA表达分别为15.71±1.78、33.70±3.35、45.83±4.37、66.98±5.89和11.69±1.25、16.55±1.37、24.73±2.74、32.65±3.39，对照组和实验组各时相均分别明显低于正常组（P＜0.05），且均随保存时间延长，ICAM-1mRNA 表达逐渐增加（P＜0.05），实验组16h后ICAM-1mRNA 表达均分别明显低于对照组相应时相（P＜0.05）。结论 丹参能够降低离体肝脏保存再灌注后肝脏组织中ICAM-1mRNA表达，对肝脏保存再灌注损伤可能具有防护作用。
【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.
To investigate the protective effect of propofol on ischemia/reperfusion induced spinal cord injury in rabbits and its influence on excitatory amino acid (EAA). Methods Sixty New Zealand white rabbits weighing 2.0-2.5 kg, half males and half females, were selected. The infrarenal circumaortic clamping model was used. And 6 mL/kg different fluids were continuously infused through a catheter into the aorta distal to the clamping site at a speed of 12 mL/(kg•h) during the 30 minutes ischemia period. According to the different infusing l iquids, the rabbits were randomized into 6 groups(n=10 per group): group A, normal sal ine; group B, 10% intral ipid; group C, propofol 30 mg/kg; group D, propofol 40 mg/kg; group E, propofol 50 mg/kg; group F, propofol 60 mg/kg. At 0, 6, 24, and 48 hours after reperfusion, neurologic outcomes were scored on a Tarlov scale system. At 48 hours after reperfusion, the number of normal neurons in the anterior spinal cord was counted, and concentration of EAA in the lumbar spinal cord was measured by high performance l iquid chromatography. Results The neuroethological score was better in groups C, D, E and F than that of groups A and B (P lt; 0.05), the score of group E was the highest (P lt; 0.05), and there was no significant difference between group A and group B (P gt; 0.05). The number of normal neurons in the anterior spinal cord of groups C, D, E and F was greater than that of groups A and B (P lt; 0.05), and group E was greater than groups C, D and F (P lt; 0.05). The concentration of EAA in groups A, B, C, D, E and F was greater than that of normal tissue, the group E was the lowest (P lt; 0.05), the groups A and B were the highest (P lt; 0.05), and there was no significant difference between group A and group B (P gt; 0.05). Concentrations of glutamate and aspartic acid were negatively correlated to normal neuron numbers in the anterior spinal cord and neuroethological scores 48 hours after reperfusion, and the corresponding correlation coefficient was — 0.613, — 0.536, — 0.874 and — 0.813, respectively (P lt; 0.01). Conclusion Propofol can significantly inhibit the accumulation of EAA in spinal cord and provide a protective effect against the ischemia/reperfusion injury induced spinal cord in rabbits.
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.
ObjectiveTo investigate the protective effects of glycine on rat sinusoidal endothelial cells (SECs) after hepatic warm ischemiareperfusion and its mechanism.MethodsSeventytwo male SD rats were randomly divided into the normal control,ischemiareperfusion,glycine plus strychnine treated and glycine treated groups. The changes of endothelin (ET),hyaluronic acid (HA),tumor necrosis factorα (TNFα) content and alanine aminotransterase (ALT), superoxide dismutase (SOD) activity as well as morphology of SECs under light microscope were observed at the time point 1,3,24 h after hepatic reperfusion. The effects of glycine on the above parameters were also observed. ResultsThe group using glycine treated, the abnormal changes of all above parameters were improved remarkably (P＜0.01 or P＜0.05). Strychnine can antagonize these effects partly.ConclusionGlycine can prevent the injury to rat SECs after hepatic warm ischemiareperfusion.It most likely acts through glycine receptor on SECs and Kupffer cells.
ObjectiveTo summarize recent researches on mechanism of the hepatic ischemic preconditioning (IPC) and its clinical applications on hepatectomy and liver transplantation. MethodsRelevant references about basic and clinical researches of hepatic IPC were collected and reviewed. ResultsRecent experimental researches indicated that IPC could relieve hepatic ischemiareperfusion injury (IRI) by remaining and improving energy metabolism of liver, regulating microcirculation disorder, decreasing the production of lipid peroxidation and oxyradical. It could also inhibit the activation of inflammatory cells and the release of cytokine, suppress cell apoptosis and induce the release of endogenous protective substance. Till now, most of the clinical researches had confirmed the protective function of hepatic IPC, but there were still some references with opposite opinions. ConclusionHepatic IPC could relieve liver IRI, but its clinical application value on hepatectomy and liver transplantation still need more researches to prove.