冬眠动物达乌尔黄鼠离体心脏对缺灌和再灌损伤的耐受性

秋季未入眠之达乌尔黄鼠离体心脏用Ｌａｎｇｅｎｄｏｒｆ方法灌流，平衡１０ｍｉｎ，全心缺灌１５ｍｉｎ，然后再灌１０ｍｉｎ。于缺灌期和再灌期分别定时收集心脏冠脉流出液，测定流份中肌酸激酶（ＣＫ）的活性（Ｕ·Ｌ－１），同时记录心电图和心脏收缩力。此外，用恒温动物大鼠作为冬眠动物黄鼠的实验对照，经受完全相同的实验处理。缺灌１５ｍｉｎ期内，两种动物心脏皆有大量ＣＫ释放，释放量与缺灌时间呈线性关系。但黄鼠各采样点ＣＫ释放值都低于大鼠，提示黄鼠心脏对缺灌损伤的耐受性强于大鼠。再灌期大鼠心脏有两个ＣＫ释放峰，而黄鼠仅有第Ⅰ峰，且其活性值（１７９±３２Ｕ·Ｌ－１）显著低于大鼠（２５５±１７Ｕ·Ｌ－１，Ｐ＜０．０５）。再灌期黄鼠室颤和室速发生率以及心脏收缩幅度下降百分率皆显著低于大鼠（Ｐ＜０．０１）。上述结果证明，与大鼠相比较。

mito K_(ATP)和κ-阿片受体介导肢体缺血后处理对抗大鼠脑缺血/复灌损伤

目的:观察肢体缺血后处理(LIPC)在大鼠局灶性脑缺血/复灌损伤中的神经保护作用及其作用机制。方法:将大鼠随机分为6组:空白对照组,单侧LIPC组,双侧LIPC组(bLIPC),bLIPC+mito KATP阻断剂5-hydroxyde-canoate(5-HD)预处理组,bLIPC+κ-阿片受体拮抗剂nor-binaltorphimine(nor-BNI)预处理组,bLIPC+双侧后肢体外循环组。采用线栓法建立大鼠大脑中动脉栓塞(MCAO)模型,术后进行神经系统症状评分,血浆强啡肽和脑啡肽水平测定,大脑梗死面积测定。结果:单侧LIPC能改善大鼠局灶性脑缺血/复灌损伤后的神经系统功能评分(P<0.05),并减少大脑梗死面积(P<0.01);而双侧LIPC能显著提高大鼠局灶性脑缺血/复灌损伤后的神经系统功能评分,并显著减少大脑梗死面积(P<0.01),比单侧LIPC的作用更为明显(P<0.05)。双侧LIPC后5、15、30min,1和2h这五个时间点,血浆强啡肽水平显著增高(P<0.01),12和24h这两个时间点恢复至正常水平;而血浆脑啡肽水平的改变与双侧LIPC前比较无显著差异(P>0.05)。nor-BNI预处理(25nmol)和5-HD预处理(10mg/kg)均消除了双侧LIPC所致的神经系统功能评分增加和大脑梗死面积减少(P<0.01)。结论:LIPC在大鼠局灶性脑缺血/复灌损伤中具有显著的神经保护作用,其作用可能与LIPC诱导内源性阿片激动剂释放和激活mitoKATP有关。

缺血预适应对大鼠乳鼠心肌细胞缺血/再灌损伤的保护作用

目的探讨缺血预适应对乳鼠心肌细胞缺血/再灌损伤的保护作用。方法复制大鼠乳鼠心肌细胞培养模型,试验分为四组:正常对照组:正常培养乳鼠心肌细胞;缺血再灌注组:缺血3h,再灌注9h;预适应组:先缺血90min,再灌注60min,再缺血3h,再灌注9h;预适应加caffeine组:缺血90min,再灌注20min后加入caffeine继续缺血40min后,再缺血3h,再灌注9h。分别测定乳鼠心肌细胞培养液中乳酸脱氢酶(LDH)、丙二醛(MDA)、超氧化物歧化酶(SOD)水平;HE检测各组心肌细胞损伤情况。结果检测乳鼠心肌细胞培养液中LDH活力、MDA水平和SOD活力时发现,缺血再灌注组和预适应加caffeine组的培养液中LDH活力、MDA水平与对照组相比明显增加,而SOD活力与对照组相比则是降低。培养的乳鼠心肌细胞的HE染色可见缺血再灌注组细胞体积变小,胞核浓缩,胞质嗜酸性增强,其病理学改变比预适应组和预适应加caffeine组严重。结论缺血预适应对大鼠乳鼠心肌细胞缺血/再灌损伤有保护作用。

Protective Effects of Tea Polyphenol on Cerebral Ischemia-Reperfusion Injury in Rats and Its Scavenging Oxy-radical and Anticerebral Lipid Peroxidation Effects

AIM To study the protective effects of tea polyphenol (TP) on cerebral ischemia reperfusion injury in rats and its scavenging oxygen free radical(OFR) activities and antilipid peroxidation in vitro . METHODS Cerebral ischemia reperfusion injury was produced by bilateral ligation of the common carotid arteries with vagus nerves and reperfusion for 45 min. The mitochondrial lipid peroxidation of rat brain induced by oxygen free radical was measured by thiobarbituric acid spectrophotometry. Superoxide anion (O 2) from xanthine xanthine oxidase system and hydroxyl radical (·OH) from Fe 2+ -H 2O 2 system were determined with spectrophotometry. RESULTS During Cerebral ischemia reperfusion,TP improved the activities of superoxide dismutase ( P 【0 05), GSH peroxidase( P 【0 01) and catalase( P 【0 01), while decreasing the maiondialdchyde content in the brain( P 【0 05) and brain water content ( P 【0 01). Tea polyphenol possessed significantly scavenging effects on ·OH produced by Fenton reaction and O 2 produced by xanthine xanthine oxidase system (the IC 50 were 2 2 mmol·L -1 and 1 9 mmol·L -1 respectively). Tea polyphenol could significant inhibit the lipid peroxidation of cerbral mitochondrial membrane induced by ·OH in a concentration dependent manner. CONCLUSION The results indicate that tea polyphenol could protect the injury on cerebral ischemia reperfusion in rats for OFR, these effects may be related to its scavenging effects on oxygen free radicals and antilipid peroxidant.

EFFECTS OF ELECTROACUPUNCTURE ON EXPRESSION OF INTERCELLULAR ADHESION MOLECULE-1 IN THE RAT OF LOCAL CEREBRAL ISCHEMIA-REPERFUSION

Objective To investigate effects of electroacupuncture （EA） on expression of intercellular adhesion molecule-1 （ICAM-1） in the rat of local cerebral ischemia-reperfusion. Methods Eighty SD rats were randomly divided into a normal control group, a sham operation group, a model group and an EA treatment group, 20 rats in each group. The thread-obstruction method was used for preparation of ischemia-reperfusion model. Zea-Longa rating criteria were used for evaluation of nervous function disorder; Immunohistochemical SABC method was used for detection of ICAM-1 expression in the microvascular endothelial cell of the ischemic brain region, and ELISA method for the soluble ICAM-1 （slCAM-1） content in peripheral blood. Re. suits After cerebral ischemia-reperfusion, both ICAM-1 expression level in the microvascular endethelium cell of the ischemic brain region and slCAM-1 content in the peripheral blood significantly increased in the model group as compared with the normal group and the sham operation group （P〈0.01）; After EA treatment, the ICAM-1 expression level in the microvascular endothelial cell of the ischemic brain region and slCAM-1 content in the peripheral blood were significantly down-regulated in the EA treatment group as com- pared with the model group （P〈 0.05）. Conclusion After cerebral ischemia-reperfusion, the microvascular endothelial cell of the ischemic brain region releases ICAM-1, which induces inflammatory injury of cerebral tissues; EA treatment can decease the expression of ICAM-1, so as to prevent the brain from the injury.

Protective Effects of Zingiberis and Acniti Praeparatae Decoction on Myocardial IschemiaReperfusion Injury in Rats

This study aimed to investigate the protective effects of zin-giberis and acniti praeparatae decoction on oxidative stress injury induced by my-ocardial ischemia reperfusion in rats. [Method] Myocardial ischemia-reperfusion was performed by ligation of the left anterior descending coronary artery for 30 min, fol-lowed by reperfusion for 60 min. The effects of zingiberis and acniti praeparatae decoction on ECG ST segment, myocardial infarction percentage, malondialdehyde （MDA） content in the serum, superoxide dismutase （SOD） activity and other indica-tors were observed. [Result] Zingiberis and acniti praeparatae decoction could effec-tively inhibit ECG ST segment elevation caused by myocardial ischemia-reperfusion injuries, reduce the percentage of myocardial infarction, decline the content of MDA in the serum, and increase the activity of SOD. [Conclusion] Zingiberis and acniti praeparatae decoction exhibits protective effects on oxidative injuries caused by my-ocardial ischemia-reperfusion injuries in rats, which may be involved in reducing the formation of myocardial free radicals and enhancing antioxidant capacity of my-ocardium.

Effect of nuclear factor kappa B on intercellular adhesion molecule-1 expression and neutrophil infiltration in lung injury induced by intestinal ischemia/reperfusion in rats

AIM： To investigate the role of nuclear factor kappa B （NF-κB） in the pathogenesis of lung injury induced by intestinal ischemia/reperfusion （I/R）, and its effect on intercellular adhesion molecule-1 （ICAM-1） expression and neutrophil infiltration. METHODS： Twenty-four Wistar rats were divided randomly into control, I/R and pyrrolidine dithiocarbamate （PDTC） treatment groups, n = 8 in each. I/R group and PDTC treatment group received superior mysenteric artery （SMA） occluding for 1 h and reperfusion for 2 h. PDTC group was administrated with intraperitoneal injection of 2% 100 mg/kg PDTC 1 h before surgery. Lung histology and bronchia alveolus lung fluid （BALF） protein were assayed. Serum IL-6, lung malondialdehyde （MDA） and myeloperoxidase （MPO） as well as the expression level of NF-κB and ICAM-1 were measured.RESULTS： Lung injury induced by intestinal I/R, was characterized by edema, hemorrhage and neutrophil infiltration as well as by the significant rising of BALF protein. Compared to control group, the levels of serum IL-6 and lung MDA and MPO increased significantly in I/R group （P=0.001）. Strong positive expression of NF-κB p65 and ICAM-1 was observed. After the administration of PDTC, the level of serum IL-6, lung MDA and MPO as well as NF-κB and ICAM-1 decreased significantly （P〈 0.05） when compared to I/R group.CONCLUSION： The activation of NF-κB plays an important role in the pathogenesis of lung injury induced by intestinal I/R through upregulating the neutrophil infiltration and lung ICAM-1 expression. PDTC as an inhibitor of NF-κB can prevent lung injury induced by intestinal I/R through inhibiting the activity of NF-κB.

Effects of Ca^(2+) channel blockers on store-operated Ca^(2+) channel currents of Kupffer cells after hepatic ischemia/reperfusion injury in rats

AIM： To study the effects of hepatic ischemia/ reperfusion （I/R） injury on store-operated calcium channel （SOC） currents （Isoc） in freshly isolated rat Kupffer cells, and the effects of Ca^2＋ channel blockers, 2-aminoethoxydiphenyl borate （2-APB）, SK＆F96365, econazole and miconazole, on Isoc in isolated rat Kupffer cells after hepatic I/R injury.METHODS： The model of rat hepatic I/R injury was established. Whole-cell patch-clamp techniques were performed to investigate the effects of 2-APB, SK＆F96365, econazole and miconazole on Isoc in isolated rat Kupffer cells after hepatic I/R injury.RESULTS： I/R injury significantly increased Isoc from -80.4±25.2pA to -159.5±34.5pA （^bp 〈 0.01, n = 30）. 2-APB （20, 40, 60, 80, 100 pmol/L）, SK＆F96365 （5, 10, 20, 40, 50 pmol/L）, econazole （0.1, 0.3, 1, 3, 10 μmol/L） and miconazole （0.1, 0.3, 1, 3, 10 μmol/L） inhibited Isoc in a concentration-dependent manner with IC50 of 37.41 μmol/L （n = 8）, 5.89 μmol/L （n = 11）, 0.21 μmol/L （n = 13）, and 0.28 μmol/L （n = 10）. The peak value of Isoc in the I-V relationship was decreased by the blockers in different concentrations, but the reverse potential of Isoc was not transformed. CONCLUSION： SOC is the main channel for the influx of Ca^2＋ during hepatic I/R injuries. Calcium channel blockers, 2-APB, SK＆F96365, econazole and miconazole,have obviously protective effects on I/R injury, probably by inhibiting Isoc in Kupffer cells and preventing the activation of Kupffer cells.

The role and modulation of autophagy in experimental models of myocardial ischemia-reperfusion injury

A physiological sequence called autophagy qualitatively determines cellular viability by removing protein aggregates and damaged cyto-plasmic constituents, and contributes significantly to the degree of myocardial ischemia-reperfusion （I/R） injury. This tightly orchestrated cata-bolic cellular‘housekeeping’ process provides cells with a new source of energy to adapt to stressful conditions. This process was first described as a pro-survival mechanism, but increasing evidence suggests that it can also lead to the demise of the cell. Autophagy has been implicated in the pathogenesis of multiple cardiac conditions including myocardial I/R injury. However, a debate persists as to whether autophagy acts as a protec-tive mechanism or contributes to the injurious effects of I/R injury in the heart. This controversy may stem from several factors including the va-riability in the experimental models and species, and the methodology used to assess autophagy. This review provides updated knowledge on the modulation and role of autophagy in isolated cardiac cells subjected to I/R, and the growing interest towards manipulating autophagy to increase the survival of cardiac myocytes under conditions of stress-most notably being I/R injury. Perturbation of this evolutionarily conserved intracellular cleansing autophagy mechanism, by targeted modulation through, among others, mammalian target of rapamycin （mTOR） inhibitors, adenosine monophosphate-activated protein kinase （AMPK） modulators, calcium lowering agents, resveratrol, longevinex, sirtuin activators, the proapoptotic gene Bnip3, IP3 and lysosome inhibitors, may confer resistance to heart cells against I/R induced cell death. Thus, therapeutic ma-nipulation of autophagy in the challenged myocardium may benefit post-infarction cardiac healing and remodeling.

Nigella sativa relieves the deleterious effects of ischemia reperfusion injury on liver

AIM: To determine whether Nigella sativa prevents hepatic ischemia-reperfusion injury to the liver. METHODS: Thirty rats were divided into three groups as sham (Group 1), control (Group 2), and Nigella sati-va (NS) treatment group (Group 3). All rats underwent hepatic ischemia for 45 min followed by 60 min period of reperfusion. Rats were intraperitoneally infused with only 0.9% saline solution in group 2. Rats in group 3 received NS (0.2 mL/kg) intraperitoneally, before isch-emia and before reperfusion. Blood samples and liver tissues were harvested from the rats, and then the rats were sacrifi ced. Serum aspartate aminotransfera-se (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) levels were determined. Total antioxidant capacity (TAC), catalase (CAT), total oxida-tive status (TOS), oxidative stress index (OSI) and my-eloperoxidase (MPO) in hepatic tissue were measured. Also liver tissue histopathology was evaluated by light microscopy. RESULTS: The levels of liver enzymes in group 3 weresignifi cantly lower than those in the group 2. TAC in liver tissue was significantly higher in group 3 than in group 2. TOS, OSI and MPO in hepatic tissue were signifi cantly lower in group 3 than the group 2. Histo-logical tissue damage was milder in the NS treatment group than that in the control group. CONCLUSION: Our results suggest that Nigella sa-tiva treatment protects the rat liver against to hepatic ischemia-reperfusion injury.

Gender differences in hepatic ischemic reperfusion injury in rats are associated with endothelial cell nitric oxide synthase-derived nitric oxide

AIM: This study was designed to examine the hypothesis that gender differences in I/R injury are associated withendothelial cell nitric oxide synthase (eNOS)-derived nitric oxide (NO).METHODS: Wistar rats were randomized into seven experimental groups (12 animals per group). Except for the sham operated groups, all rats were subjected to total liver ischemia for 40 min followed by reperfusion. All experimental groups received different treatments 45 min before the laparotomy. For each group, half of the animals (six) were used to investigate the survival; blood samples and liver tissues were obtained in the remaining six animals after 3 h of reperfusion to assess serum NO, alanine aminotransferase (ALT) and TNF-α levels, liver tissuemalondialdehyde (MDA) content, and severity of hepatic I/R injury.RESULTS: Basal serum NO levels in female sham operated (FS) group were nearly 1.5-fold of male sham operated (MS) group (66.7±11.0 μmol/L vs 45.3±10.1μmol/L, P＜0.01). Although serum NO levels decreased significantly after hepatic I/R (P＜0.01, vs sham operated groups), they were still significantly higher in female rat (F) group than in male rat (M) group (47.8±8.6 μmol/L vs 23.8±4.7 μmol/L, P＜0.01). Serum ALT and TNF-α levels, and liver tissue MDA content were significantly lower in F group than in M group (370.5±46.4 U/L, 0.99±0.11 μg/L and 0.57±0.10 μmol/g vs668.7±78.7 U/L, 1.71±0.18 μg/Land 0.86±0.11 μmol/g, respectively, P＜0.01). I/R induced significant injury to the liver both in M and F groups (P＜0.01 vs sham operated groups). But the degree of hepatocyte injury was significantly milder in F group than in M group (P＜0.05 and P＜0.01). The median survival time was six days in F group and one day in M group. The overall survival rate was significantly higher in F group than in M group (P＜0.05). When compared with male rats pretreated with saline (M group), pretreatment of male rats with 17-β- estradiol (E2) (M+E2 group) significantly increased serum NO levels and significantly decreased serum ALT and TNF-α levels, and liver tissue MDA content after I/R (P＜0.01).The degree of hepatocyte injury was significantly decreased and the overall survival rate was significantly improved in M+E2 group than in M group (P＜0.01 and P＜0.05). TheNOS inhibitor Nw-nitro-L-arginine methyl ester (L-NAME) treatment could completely abolish the protective effects of estrogen in both male and female rats. CONCLUSION: The protective effects afforded to female rats subjected to hepatic I/R are associated with eNOSderived NO.

Reduction of ischemia reperfusion injury after liver resection and hepatic inflow occlusion by α-lipoic acid in humans

AIM： To evaluate the protective effects of preconditioning by α-lipoic acid （LA） in patients undergoing hepatic resection under inflow occlusion of the liver. METHODS： Twenty-four patients undergoing liver resection for various reasons either received 600 mg LA or NaCI 15 min before transection performed under inflow occlusion of the liver. Blood samples and liver wedge biopsy samples were obtained after opening of the abdomen immediately after inflow occlusion of the liver, and 30 min after the end of inflow occlusion of the liver. RESULTS： Serum levels of aspartate transferase and alanine transferase were reduced at all time points in patients who received LA in comparison to those who received NaCL. This was accompanied by reduced histomorphological features of oncosis. We observed TUNEL-positive hepatocytes in the livers of the untreated patients, especially after 30 min of ischemia. LA attenuated this increase of TUNEL-positive hepatocytes. Under preconditioning with LA, ATP content was significantly enhanced after 30 min of ischemia and after 30 min of reperfusion. CONCLUSION： This is the first report on the potential for LA reducing ischemia/reperfusion injury （IRI） of the liver in humans who were undergoing liver surgery. Beside its simple and rapid application, side effects did not occur. LA might therefore represent a new strategy against hepatic IRI in humans.

Identification of differentially expressed genes after partial rat liver ischemia/reperfusion by suppression subtractive hybridization

AIM: To identify potential diagnostic target genes in early reperfusion periods following warm liver ischemia before irreversible liver damage occurs. METHODS: We used two strategies (SSH suppression subtractive hybridization and hybridization of cDNA arrays) to determine early changes in gene expression profiles in a rat model of partial WI/R, comparing postischemic and adjacent nonischemic liver lobes. Differential gene expression was verified (WI/R; 1 h/2 h) and analyzed in more detail after warm ischemia (1 h) in a reperfusion time kinetics (0, 1, 2 and 6 h) and compared to untreated livers by Northern blot hybridizations. Protein expression was examined on Western blots and by immunohistochemistry for four differentially expressed target genes (Hsp70, Hsp27, Gadd45a and IL-1rI). RESULTS: Thirty-two individual WI/R target genes showing altered RNA levels after confirmation by Northern blot analyzes were identified. Among them, six functionally uncharacteristic expressed sequences and 26 known genes (12 induced in postischemic liver lobes, 14 with higher transcriptional expression in adjacent nonischemic liver lobes). Functional categories of the verified marker genes indicate on the one hand cellular stress and tissue damage but otherwise activation of protective cellular reactions (AP-1 transcription factors, apoptosis related genes, heat shock genes). In order to assign the transcriptional status to the biological relevant protein level we demonstrated that Hsp70, Hsp27, Gadd45a and IL-1rI were clearly up-regulated comparing postischemic and untreated rat livers, suggesting their involvement in the WI/R context. CONCLUSION: This study unveils a WI/R response gene set that will help to explore molecular pathways involved in the tissue damage after WI/R. In addition, these genes especially Hsp70 and Gadd45a might represent promising new candidates indicating WI/R liver damage.

Apoptosis induction with polo-like kinase-1 antisense phosph-orothioate oligodeoxynucleotide of colon cancer cell line SW480

AIM： To investigate the effects of polo-like kinase-1 （PLK1） antisense phosphorothioate oligodeoxynucleotide （ASODN） on apoptosis and cell cycle of human colon cancer cell line SW480. METHODS： After SW480 colon cancer cells were transfected with PLK1 ASODN, Northern and Western blot analyses were used to examine PLK1 gene expression in cancer cells. We studied apoptosis using terminal uridine deoxynucleotidyl nick end labeling. Apoptosis and cell cycle of SW480 cells were examined by fluorescence-activated cell sorter scan. RESULTS： The levels of PLK1 mRNA and protein were greatly inhibited by PLK1 ASODN in SW480 cancer cells transfected with PLK1 ASODN. Apoptosis index （AI） induced PLK1 ASODN in a time- and dose-dependent manner. Results from FLM showed that sub-2N DNA content of transfected cancer cells was significantly increased and arrested at G2/M compared with control groups. CONCLUSION： PLK1 ASODN can induce apoptosis of human colon cancer cell line SW480.

Effect of shenfu injection on gastrointestinal microcirculation in rabbits after myocardial ischemia-reperfusion injury

AIM： To investigate the effect of shenfu injection on gastrointestinal microcirculation after myocardial ischemic-reperfusion （IR） injury in rabbits and probe into the mechanism. METHODS： Forty healthy flap-eared white rabbits were randomly divided into 4 groups： IR injury control group （group Ⅰ ）, shenfu injection 5 mL/kg per h group （group Ⅱ）, shenfu injection 10 mL/kg per h group （group Ⅲ） and shenfu injection 20 mL/kg per h group （group Ⅳ）. The four groups were treated with Lactated Ringer＇s solution, shenfu injection 5, 10, and 20 mL/ kg per h were infused intravenously 30 min before experiment respectively. The values of hemodynamics [mean arterial pressure （MAP）, heart rate （HR）, gastric intramucosal partial pressure of carbon dioxide （PCO2）, blood gas analysis and pH] were measured and compared with those before myocardial ischemia, 60 min after myocardial ischemia and 60, 90, and 180 rain after reperfusion. RESULTS： The MAP, HR and gastric intramucosal pH were （70.50 ± 4.50） kPa, （165 ± 14） beats per rain, 7.032 ± 0.024 in group Ⅰ 60 min after myocardial ischemia, which were significantly decreased compared with those before myocardial ischemia （88.50 ± 9.75 kPa, 217 ± 18 beats per rain, 7.112 ± 0.035, P 〈 0.05）. The MAP, HR and gastric intramucosal pH were significantly decreased in group Ⅰ 60, 90, and 180 min after reperfusion （61.50 ± 5.25 kPa, 133 ± 31 beats per rain, 6.997 ± 0.025） compared with those before reperfusion respectively （P 〈 0.05）, whereas the values were insignificantly different in groups Ⅱ, Ⅲ or Ⅳ after reperfusion, compared with those before reperfusion, and there were no significant differences between groups Ⅱ, Ⅲ, and Ⅳ after reperfusion. CONCLUSION： Pre-infusion of shenfu injection has a protective effect on gastrointestinal microcirculation after myocardial IR injury in rabbits, in a dose independent manner.

Reduced antioxidant level and increased oxidative damage in intact liver lobes during ischaemia-reperfusion

AIM： To determine whether increased blood flow of the liver can cause oxidative stress and hepatocyte damage, and to elaborate methods suitable for measuring the antioxidant defence during hepatic surgery on rat model.METHODS： In nembutal narcosis, the left lateral and the medial lobes of the liver were clipped for 45 rain to make the total blood supply flow through the other lobes. Total antioxidant status, glutathione peroxidase and superoxide dysmutase activity, as well as the concentrations of diene conjugates and free sulphydril groups, H-donating ability and reducing power of the liver samples were determined. Chemiluminescent intensity of the liver was also measured. Metal ions （Al, Ca, Cu, Fe, Mg, Mn, Zn） and P and S concentrations of the liver were determined with an inductively coupled plasma optical emission spectrometer and Se content was measured by cathodic stripping voltammetry.RESULTS： Glutathione peroxidase and superoxide dysmutase activities of the liver decreased significantly in the hyperemia group compared to those observed in the sham operated group. The level of total antioxidant status was also significantly lower in the hyperemia group. H-donating ability, reducing power and free sulphydril group concentration showed the same tendency. A significant correlation （P〈0.05） was found between the changes in non-specific antioxidant activities. This pointed to simultaneous activity of the antioxidant defence system. Al, Cu, Mn, Zn, and S were lower in the hyperemia group than in the sham operated group when the levels of Ca, Fe, Mg, Se and P ions were higher during hyperemia.CONCLUSION： Oxidative stress is one of the main factors for the injury of intact liver lobes during ischaemia-reperfusion.

Effect of intestinal ischemia-reperfusion injury on protein levels of leptin and orexin-A in peripheral blood and central secretory tissues

AIM: To explore the effect of intestinal ischemia-reperfusion injury on protein levels of leptin and orexin-A in peripheral blood and their central secretory tissues and to find out the role leptin and orexin-A play in acute inflammatory responses.METHODS: An intestinal ischemia-reperfusion (I/R)injury model of rats was established and rats were divided randomly into six groups: sham-operation group, 60 min ischemia/30 min reperfusion group (I60'R30'), I60'R90',I60'R150', I60'R240' and I60'R360', 9 rats each group.Two highly-sensitive radioimmunoassays for leptin and orexin-A were established and used to check the change of their concentrations in peripheral blood and central secretory tissues before and after intestinal I/R injury.RESULTS: Compared with the serum leptin level before injury, it decreased significantly in I60'R30' group and increased significantly in I60'R360' group; compared to sham-operation group after injury, serum leptin level increased significantly in I60'R360' group; compared to sham-operation group after injury, adipose leptin levels decreased significantly in I60'R30' and I60'R90' groups,while increased significantly in I60'R360' group. There was no significant difference between the expression levels of orexin-A before and after I/R injury.CONCLUSION: Leptin has a time-dependent response and orexin-A has a delayed response to acute inflammatory stimuli such as intestinal I/R injury and they may participate in metabolic disorders in injury as inflammatory cytokines.

The effects of Shuxuetong on the pathology of cerebral ischemia-reperfusion injury and GABA and TNF-α expression in gerbil models

Objective To study the protective effect and mechanism of Shuxuetong on gerbil brain tissue from the area of ischemia-reperfusion. Methods Cerebral ischemia-reperfusion animal model by transient clipping bilateral common carotid arteries in gerbils. Pathological changes in the hippocampal tissue were observed at different reperfusion time （12 h, 3 d, 7 d）. The expression levels of GABA and TNF-α in the hippocampal CA1 subfield were observed using immunohistochemitry at 12 h, 3 d after reperfusion. The difference of above indices among false operation group, ischemia-reperfusion group and treatment group were compared. Results The injuries of pathology to hippocampal area in ischemia-reperfusion group were more serious than treatment group. The expression levels of GABA in treatment group were significantly increased compared with ischemia-reperfusion group, but the expression levels of TNF-α between the two groups have no difference. Conclusion Shuxuetong has protective effect on brain tissue of ischemia-reperfusion by enhancing the expression of GABA in the hippocampal tissue.

Acid fibroblast growth factor reduces rat intestinal mucosal damage caused by ischemia-reperfusion insult

AIM： To detect the effects of acid fibroblast growth factor （aFGF） on apoptosis and proliferation of intestinal epithelial cells in differentiation or proliferation status to explore the protective mechanisms of aFGF. METHODS： Wistar rats were randomly divided into sham-operated control group （C, n = 6）, intestinal ischemia group （I, n = 6）, aFGF treatment group （A, n =48） and intestinal ischemia-reperfusion group （R, n =48）. Apoptosis of intestinal mucosal cells was determined with terminal deoxynucleotidyl transferasemediated dUTP-biotin nick-end labeling （TUNEL） technique. Proliferating cell nuclear antigen （PCNA） protein expression and distribution were detected with immunohistochemical method. Plasma levels of D-lactate were determined with modified Brandts method. RESULTS： In A group, administration of exogenous aFGF could improve intestinal histological structure and decrease plasma D-lactate levels at 2-12 h after the reperfusion compared with R group. The apoptotic rates and PCNA protein expressions were not increased until 2 h after reperfusion and were maximal at 12 h. After reperfusion for 2-12 h, the apoptotic rates were gradually augmented along the length of jejunal crypt-villus units. Administration of aFGF could significantly reduce the apoptotic response at 2-12 h after reperfusion （P〈0.05）. Apoptosis rates in villus and crypt epithelial cells in A group at 12 h after reperfusion were （62.5±5.5）% and （73.2±18.6）% of those in R group, respectively. Treatment of aFGF could apparently induce protein expression of PCNA in intestinal mucosal cells of A group compared with R group during 2-22 h after reperfusion （P〈0.05）. There were approximately 1.3- and 1.5-times increments of PCNA expression levels in villus and crypt cells in A group at 12 h after reperfusion compared with R group, respectively. CONCLUSION： Intestinal I/R insult could lead to histological structure change and apoptotic rate increment. The protective effects of aFGF against ischernia/reperfusion in rat intestinal rnucosa might be partially due to its ability to inhibit ischernia/reperfusioninduced apoptosis and to promote cell proliferation of crypt cells and villus epithelial cells.

Mild hypothermia protects liver against ischemia and reperfusion injury

AIM: To determine whether mild hypothermia could protect liver against ischemia and reperfusion injury in pigs. METHODS: Twenty-four healthy pigs were randomly divided into normothermia, mild hypothermia and normal control groups. The experimental procedure consisted of temporary interruption of blood flow to total hepatic lobe for different lengths of time and subsequent reperfusion. Hepatic tissue oxygen pressure (PtiO2) and aspartate aminotransferase (AST) values were evaluated, and ultrastructural analysis was carried out for all samples. RESULTS: Serum AST was significantly lower, and hepatic PtiO2 values were significantly higher in the mild hypothermia group than in the normothermia group during liver ischemia-reperfusion periods (P= 0.032, P= 0.028). Meanwhile, the histopathologic injury of liver induced by ischemia-reperfusion was significantly improved in the mild hypothermia group, compared with that in the normothermia group. CONCLUSION: Mild hypothermia can protect the liver from ischemia-reperfusion injury in pigs.