Objective To investigate the effect of S-adenosylmethionine (SAM) on mitochondrial injury that was induced by ischemia-reperfusion in rat liver. Methods Fifty-four rats were randomly divided equally into 3 groups: control group, ischemia-reperfusion group (I/R group), and SAM-treated group (SAM group). Hepatic ischemia had been only lasted for 30 min by obstructing the blood stream of hepatic portal vena (the portal vena was only separated but not obstructed in control group). The rats of SAM group received SAM intraperitoneally 2 h prior to ischemia. Blood samples of each group were collected from the inferior cava vena at 0, 1 and 6 h after reperfusion and the serum levels of AST and ALT were detected. Mitochondrial super oxidedismutase (SOD), malondialdehyde (MDA), adenosine triphosphate (ATP) and energy charge (EC) in samples of liver tissue were detected, and the mitochondrial ultrastructure was observed with electronmicroscope. Results The serum levels of AST, ALT and mitochondrial MDA at 0, 1 and 6 h after reperfusion in the I/R group were significantly higher than those in the control group, whereas the levels of mitochondrial SOD, ATP and EC were significantly lower than those in the control group (P<0.01). Except the value of 0 h, when it comes to SAM group, the levels of AST, ALT and mitochondrial MDA were significantly lower (P<0.05) and the levels of mitochondrial SOD, ATP and EC were significantly higher (P<0.05, P<0.01) than those in the I/R group, respectively. The mitochondrial ultrastructure was injured obviously in I/R group when compared with that in control group. The number of mitochondria decreased and the mitochondria swelled, making the crista became obscure and the density of matrix became lower. The above changes in SAM group were less obvious when compared with those in I/R group. Conclusion SAM may protect mitochondrion against hepatic ischemia injury, since it may prevent mitochondrial lipid peroxidation, increase ATP, and eventually improve energy metabolism after ischemia-reperfusion.
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.
Objective To study the effect of dexamethasone to protect flaps from an ischemia-reperfusion injury and elucidate its mechanism of regulating the death course of the neutrophils.Methods The rats were randomly divided into 3 groups.The vein of the rat was clamped for 8 h after the flap had formed. Group A: the normal flap; Group B: the saline control flap; Group C: the treatment flap with dexamethasone. The survival area of the flaps was measured at 7 days; the apoptotic and necrotic neutrophils,tumor necrosis factor α (TNF-α), and interleukin 10 (IL-10) concentrations were measured. Results The flap survival areas in Groups A and C were larger than those in Group B. The apoptotic neutrophils in Group B were fewer than those in Groups A and C on the 1st and 3rd days after operation; however, they were more in number in Group B than in groups A andC on the 6th day. The necrotic cells in Group B were more in number than those in Groups A and C. In Group B, the plasma TNF-α concentration reached the maximum level at 1 h,while the IL-10 level reached the lowest 3 h after the reperfusion. In Group C, the TNF-α concentration was lower than that in Group B and decreased dramatically at 6 h. The IL-10 concentration was the lowest at 1 h, and increased rapidly at 3 h. Thus, ischemia reperfusion could injure the flaps, probably through the abnormal action of the neutrophils, such as the disordered secretion of the cytokines and abnormal death course of the neutrophils. Conclusion Dexamethasone can protect the flap from an ischemia-reperfusion injury by its regulation for the neutrophil function.
Objective To establish a new model on isolated human cadaver testes with ischemiareperfusion (I/R). MethodsThirteen isolated cadaver testes contributed by 13 persons were preserved under 0℃-4℃ hypothermia and then reperfused under 37℃. Histological and histochemical changes were observed. Results4℃ cold ischemia in 12 hours induced only trivial swelling and vascular degeneration of endothelial cells (ECs), obvious pathologic changes occurred after 24 hours, including detachment of ECs, separation between basement membrane and seminiferous epithelium, degeneration and detachment of spermatogenous cell and edema of mesenchyme. Injury was worse along with the prolongation of cold preservation time. Changes of LDH and SDH activities were found by histochemical staining. Reperfusion following 6 hours ischemia induced tissue injury and unusual enzyme activity. All changes were more obvious after reperfusion following 12,18,24 or 36 hours cold ischemia.Conclusion This new model on isolated cadaver testes with ischemiareperfusion is successful, it can substitute other solid organs of human beings for I/R injury study.
Objective To observe the protective effects of diazoxide-preconditioning on myocardial ischemiareperfusion injury of rats and discuss its possible mechanisms. Methods Fourteen healthy SD rats were randomly divided into two groups(7 each group),In diazoxide-preconditioning group diazoxide was injected with the dosage of 12.5mg/kg through the vein,and in control group the media with the same amount was only given before ischemia. The left anterior descending branch was ligated for 2 hours. The heart was quickly excised after 2 hours reperfusion to be used for measurement of the quantity of malondialdehyde(MDA), the activity of superoxide dismutase (SOD), the size of myocardial infarct area, and the cell apoptosis and ultrastructure in ischemic area. Results Compared with the control group, the quantity of MDA,the percentage of the weight of myocardial infarct area/ischemic area, and the rate of cell apoptosis in the diazoxide-preconditioning group were greatly reduced (P〈0.05, 0. 01). The damage of cell uhrastructure was obviously alleviated,Conclusion Diazoxide-preconditioning provides evident cardioprotective effect on the myocardial ischemia-reperfusion injury of rats.
OBJECTIVE: To investigate the injury on isolated testes induced by ischemia/reperfusion(I/R), and the protective effect of Yisheng injection on the injury. METHODS: Twenty-six isolated cadaver testes contributed by 13 persons were preserved with 4 degrees C 250 ml hypertonic citrate alloxuric (HCA) solution and then reperfused with 37 degrees C 500 ml HCA. Solution of experimental group contained 500 micrograms/ml Yisheng injection. In simple cold preservation test, involving in 8 experimental and 8 control testes, a series of time points (6, 12, 18, 24, 36, 48, 60, 72 hours) were set to harvest. 10 testes (1 testis respectively on 6, 12, 18, 24 and 36 hours in experimental and control groups) were reperfused with 37 degrees C HCA for 6 and 12 hours. Histological and histochemical changes were observed. RESULTS: In the experimental testes, 4 degrees C cold preservation in 24 hours could not induce obvious pathologic changes. After 24 hours, changes such as swelling, vacuolar degeneration or detachment of endothelial cells (ECs), separation between basement membrane and seminiferous epithelium, mal-alignment of spermatogenous cell and edema of mesenchyme could be observed. In the testes preserved for 12 hours, the activity of lactic dehydrogenase(LDH) and succinic dehydrogenase (SDH) increased, then fallen after 24 hours. The activity of Nitric oxide synthetase(NOS) decreased after 18 hours. All changes were more obvious after following 37 degrees C reperfusion. In the control testes, swelling and vacuolar degeneration of ECs occurred on 12 hours cold preservation, and injury was worse along with the prolongation of cold preservation time. Pathologic changes of ECs, seminiferous epithelium and mesenchyme were serious after 37 degrees C reperfusion. CONCLUSION: 4 degrees C cold preservation in 24 hours can only cause mild ECs’ injury, and obvious abnormal testes’ histological profile can be observed beyond 24 hours. 37 degrees C reperfusion will make injury worse. Yisheng injection can keep isolated testes histologic structure well in 24 hours cold preservation, and it has protective effect on I/R injury.
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
【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.
【Abstract】Objective To observe the synthesis of TLR2 protein and its mRNA expression in Kupffer cells (KCs) and sinusoidal endothelial cells(SECs).Methods Thirty-two BALB/c mice divided into two groups (operation group and false operation group) were used to prepare the model of partial hepatic ischemia/reperfusion (I/R) injury. After injury KCs and SECs were isolated with twosteps situ perfusion technique. And these cells were dyed by rat anti-mouse TLR2 IgG and anti-rat IgG2b labeled with flurescein isothiocyanate (FITC). The sysnthesis of TLR2 protein were determined by flow cytometric (FCM) analysis and real time reverse transcription polymerase chain reaction (Real-Time RT-PCR) analysis for gene expression.Results As for KCs: TLR2 expression was significant higher in operation group, compared with false operation group 〔protein expression: (9.19±1.07)% vs (1.52±0.21)%, P<0.01; gene expression: 0.54±0.77 vs 2.62±2.19, P<0.05〕. But there were no significant differences with expression in SECs. Conclusion Synthesis of TLR2 protein and its gene expression increased in KCs in the mouse partial hepatic ischemia-reperfusion injury.
Objective To determine whether the different durations and times of the ischemic preconditioning affect the effectiveness of the ischemic preconditioning. Methods Ninety male Wistar rats were randomly divided into the control group and the eight preconditioned groups of 10 rats each. A transverse rectus abdominis musculocutaneous flap (TRAM) was elevated in each rat. The flaps were preconditioned by clamping the pedicle and reperfusing for 5 or 10 minutes per cycle. This was repeated for one or two cycles. The controls were simply perfused for 30 minutes. Each flap was then subjected to 4 hours of the global ischemia. Three rats in each group were killed for anestimate of the water content in the muscle and for observation on the muscularstructure under microscope. The flap surface survival areas of the other rats were calculated on the 7th postoperative day by the computerized video planimetry. Results The water content in the muscle was evidently reduced. The mean survival area of the flap in every preconditioned group increased by2-3 times compared with that of the controls(P<0.001). The different proceduresof the ischemic preconditioning produced different protective effects. Conclusion The ischemic preconditioning is an available means to alleviate an ischemiareperfusion injury to the transverse rectus abdominis musculocutaneous flap in rats. The effect of the ischemic preconditioning is affected by the duration and time of the ischemic preconditioning.