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 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】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.
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 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.
To investigate the effect of propofol intra-aortic and intravenous infusion on the concentration of propofol for an ischemia-reperfusion spinal cord injury in rabbits. Methods Forty-six healthy adult New Zealand white rabbits were randomly divided into 3 groups: sal ine infusion group (group N, n=10), propofol intra-aortic infusion group (group A, n=16) and propofol intravenous infusion group (group V, n=16). The infrarenal abdominal aorta was occluded for 30 min during which propofol 50 mg/kg was infused continuously intra-aortic or intravenous with a pump in group A and V. In group N, the same volume of normal sal ine was infused in the same way and at the same rate as in group A. Upon reperfusion, propofol concentration of the spinal segments of L4-6 and T6-8 was examined in group A and V. At 48 hoursafter reperfusion, the neurological outcomes were recorded in each group. Results Mean blood pressure in group V from the time of 5 minutes after occlusion decreased more than in group N (P lt; 0.05) and than in group A from the time of 10 minutes after occlusion(P lt; 0.05). The mean blood pressure in group N increased more than in group A from 15 minutes after occlusion (P lt; 0.05). The heart rate increased more in group V from 10 minutes after occlusion than in group N and A (P lt; 0.05) in which no difference was observed. The propofol concentration in L4-6 of group A (26 950.5 ± 30 242.3) ng/g was higher than that in T6-8 of group A (3 587.4 ± 2 479.3) ng/g and both L4-6 (3 045.9 ± 2 252.9) ng/g and T6-8 (3 181.1 ± 1 720.9) ng/g of group V(P lt; 0.05). The paraplegia incidence was lower (30%) and the median of normal neurons was higher (8.4) in group A than in group N (80%, 2.2) and group V(100%, 1.9), (P lt; 0.05). There was no significant difference in group N and V in paraplegia incidenceand the median of normal neurons (P gt; 0.05). Conclusion Intra-aortic infusion shows a better neurological outcome than intravenous infusion and could contribute to higher concentration of propofol in the ischemia spinal cord.
Objective Isoflurane has an acute preconditioning effectiveness against ischemia in kidney, but this beneficial effectiveness can only last for 2-3 hours. To investigate whether isoflurane produces delayed preconditioningagainst renal ischemia/reperfusion (I/R) injury, and whether this process is mediated by hypoxia inducible factor 1α(HIF- 1α). Methods A total of 52 male C57BL/6 mice were randomly assigned to 4 groups (n=13 in each group): the controlgroup (group A), PBS/isoflurane treated group (group B), scrambled small interference RNA (siRNA)/isoflurane treated group (group C), and HIF-1α siRNA/isoflurane treated group (group D). In groups C and D, 1 mL RNase-free PBS containing 50 μg scrambled siRNA or HIF-1α siRNA was administered via tail vein 24 hours before gas exposure, respectively. Equivalent RNasefree PBS was given in groups A and B. Then the mice in groups B, C, and D were exposed to 1.5% isoflurne and 25%O2 for 2 hours; while the mice in group A received 25%O2 for 2 hours. After 24 hours, 5 mice in each group were sacrificed to assesse the expressions of HIF-1α and erythropoietin (EPO) in renal cortex by Western blot. Renal I/R injury was induced with bilateral renal pedicle occlusion for 25 minutes followed by 24 hours reperfusion on the other 8 mice. At the end of reperfusion, the serum creatinine (SCr), the blood urea nitrogen (BUN), and the histological grading were measured. Results The expressions of HIF-1α and EPO in groups B and C were significantly higher than those in group A (P lt; 0.01). The concentrations of SCr and BUN in groups B and C were significantly lower than those in group A, as well as the scores of tubules (P lt; 0.01), and the injury of kidney was amel iorated noticeably in groups B and C. The expressions of HIF-1α and the concentrations of SCr and BUN in group D were significantly lower than those in group A (P lt; 0.01). Compared with groups B and C, the expression of HIF- 1α and EPO in group D decreased markedly (P lt; 0.01), the concentrations of SCr and BUN were increased obviously, as well asthe scores of tubules (P lt; 0.01), and the renal injury was aggratived significantly. Conclusion Isoflurane produces delayed preconditioning against renal I/R injury, and this beneficial effectiveness may be mediated by HIF-1α.
【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.
Objective To investigate the effects of ischemic postconditioning （IPO） on inflammatory response inischemia-reperfusion （IR） injury of rat lungs in vivo. Methods Forty SD rats were randomly divided into 5 groups inclu-ding a sham surgery group （S group），a 30-minute IR group （I/R-30 group），a 120-minute IR group（IR-120 group），a 30-minute IPO group （IPO-30 group），and a 120-minute IPO group （IPO-120 group）. There were 8 rats in each group. All therats received left thoracotomy after anesthesia. In the sham surgery group，a line was only placed around the left hilum butnot fastened. In the I/R-30 group and I/R-120 group，a line was fastened to block the blood flow of the left lung for 1 hour，then loosened for reperfusion for 30 minutes and 120 minutes respectively. In the IPO-30 group and IPO-120 group，afterblocking the blood flow of the left lung for 1 hour，the left hilum was fastened for 10 seconds and loosened for 10 seconds（repeating 3 times for 1 minute），then the line was loosened for 30 minutes and 120 minutes respectively. The levels of interleukin-10 （IL-10） in lung tissues and soluble intercellular adhesion molecule-1 （sICAM-1） in plasma were measured. Histopathological changes of lung tissues were observed and diffuse alveolar damage （DAD） scores was calculated.Results The levels of plasma sICAM-1 in the I/R-30 group and I/R-120 group were significantly higher than that of S group ［（2.140±0.250）μg/L vs. （0.944±0.188）μg/L，P=0.003；（2.191±0.230）μg/L vs. （0.944±0.188）μg/L，P=0.003］. IL-10levels in lung tissues in the I/R-30group and I/R-120 group were also significantly higher than that of S group［（15.922±0.606）pg/mg pro vs. （7.261±0.877）pg/mg pro，P=0.037；（17.421±1.232）pg/mg pro vs. （7.261±0.877）pg/mg pro，P=0.042］. Pathologic lesions of lung tissues in the I/R-30 group and I/R-120 group were more severe than that of S group. After IPO, plasma sICAM-1 levels in the IPO-30 group and IPO-120 group were significantly lower than those in the I/R-30group and I/R-120 group respectively ［（1.501±0.188）μg/L vs.（2.140±0.250）μg/L，P=0.038；（1.350±0.295）μg/L vs.（2.191±0.230）μg/L，P=0.005］. IL-10 levels in lung tissues in the IPO-30 group and IPO-120 group were significantly higherthan those in the I/R-30 group and I/R-120 group respectively ［（20.950±1.673）pg/mg pro vs.（15.922±0.606）pg/mgpro，P=0.008；（25.334±1.173）pg/mg pro vs.（17.421±1.232）pg/mg pro，P=0.006］. DAD scores in the IPO-30 group andIPO-120 group were significantly lower than those in the I/R-30 group and I/R-120 group respectively ［6.8±1.4 vs. 11.5±1.9，P=0.007；7.5±1.6 vs. 13.2±1.7，P=0.005］. Pathological lesions of the lung tissues of IPO groups were less severe than those of I/R groups. Conclusion IPO can attenuate IR injury by inhibiting inflammatory response in rat lungs.
【Abstract】 Objective To investigate the effect of verapamil on apoptosis, calcium and expressions of bcl-2 and c-myc of pancreatic cells in ischemia-reperfusion rat model. Methods Wistar rats were randomly divided into three groups: control group （n=10）; ischemia-reperfusion group （n=10）; verapamil treatment group （n=10）. The anterior mesenteric artery and the celiac artery of rats in both ischemia-reperfusion group and verapamil treatment group were occluded for 15 min followed by 12-hour reperfusion. Verapamil （1 mg／kg） was injected via caudal vein to the rats in verapamil treatment group 15 min before occlusion and 1 hour after the initiation of reperfusion, respectively; and ischemia-reperfusion group was given the same volume of salient twice intravenously. Pancreatic tissues were collected from the dead rats after twelve hours since the reperfusion. The pathologic characters of pancreatic tissue were observed under light microscope; The level of calcium in the tissue was measured by atomic absorption spectrometer; TUNEL was used to detect apoptosis of pancreatic cells; and the expressions of c-myc and bcl-2 in the cells were also analyzed by immunohistochemistry technique and flow cytometry. Results The pathologic change in verapamil treatment group was less conspicuous than that of ischemia-reperfusion group. Both the calcium level and the number of apoptotic cells in verapamil treatment group were less than those of ischemia-reperfusion group 〔（411.1±55.8） μg/g dry weight vs （470.9±31.9） μg/g dry weight, P＜0.05 and （9.5±2.9）% vs （18.4±3.1）% 〕, P＜0.05. After taking verapamil, the number of apoptotic cells decreased, whereas the expressions of bcl-2 and c-myc increased. The fluorescent indexes of bcl-2 and c-myc in verapamil treatment group were significantly higher than those of ischemia-reperfusion group (1.72±0.11 vs 1.41±0.07, P＜0.05; 1.76±0.19 vs 1.55±0.13, P＜0.05. Conclusion Ischemia-reperfusion injury can induce apoptosis of pancreatic cells. Verapamil could protect the injured pancreatic tissue by reducing the level of calcium, stimulating the expressions of bcl-2 and c-myc and inhibiting apoptosis of pancreatic cells.