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.
【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.
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)
【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.
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.
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 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.