Effect of cardiopulmonary bypass for 30 min on structure and mechanical properties of erythrocyte membrane surface

AIM: To observe and analyze the effect of cardiopulmonary bypass(CPB) for 30 min on surface ultra-structure and mechanical properties of the erythrocyte membrane by atomic force microscopy(AFM).METHODS: Ten cases of elective patients in cardiac surgery were selected in the study and divided into control(CON) group and CPB group. The central venous blood(2 mL) before surgery and 30 min after CPB was collected with heparin anticoagulation. The non-circular red blood cells were counted under a stand fluorescence microscope. AFM was used to examine the ultrastructure of the membrane surface and measure the force curve of the erythrocytes.RESULTS: The percentage of non-circular red blood cells in CPB group showed no statistically significant differences as compared with CON group. AFM images showed that the significant differences of membrane surface concave and convex, evenness, particle distribution, the surface average roughness(Ra), the surface root mean square roughness(Rq) and cell membrane adhesion between CPB group and CON group were observed. However, the membrane deformation resilience and curve slope had no significant difference between the 2 groups.CONCLUSION: Cardiopulmonary bypass for 30 min changes the morphology and ultrastructure of the erythrocyte membrane surface, and increases the adhesion between cells.     

The application of atomic force microscope in clinic diagnosis of erythrocytes

AIM: To investigate the application of atomic force microscope (AFM) in clinic diagnosis. METHODS: Topographic images and some parameters of large range field and microstructures of erythrocytes in the blood of normal subjects, lung cancer and myelodisplastic syndrome (MDS) patients were examined by atomic force microscope. RESULTS: Many clear topographic images of many erythrocytes, single erythrocyte, and microstructure of erythrocyte membrane surface were obtained. Many erythrocytes in lung cancer patients were found to change into echinocytes. One erythrocyte had 10-20 protuberances, most of which, with a mean width of 589. 0 nm and a length of 646. 7 nm, were on the edge of cells. The protuberances on the center of echinocytes are lodged and embedded. The erythrocytes of MDS patients were biconcave in shape. Many apertures with different diameters of tens to hundreds nanometer appeared on the surface of cell membrane. CONCLUSIONS: AFM can be widely applied in clinic pathological inspection, including quantification of cells, obtainment and comparison of many parameters (such as diameter, thickness, volume, surface, surface area/volume ratio), observation of topograph of single cell, and observation and comparison of membrane surface microstructure of cells, and so on.     

Emodin inhibits proliferation and blocks cell cycle of human breast cancer MCF-7 cells

AIM：To investigate the effects of emodin on the proliferation of human breast cancer MCF-7 cells and its mechanisms. METHODS：MTT assay was used to observe the viability of MCF-7 cells. The cell cycle distribution and apoptosis of MCF-7 cells was analyzed by flow cytometry. The membrane surface morphology and three-dimensional ultrastructure of MCF-7 cells were observed under atomic force microscope (AFM). RESULTS：MTT assay showed that emodin could inhibit MCF-7 cell proliferation in a dose-dependent manner. Flow cytometric analysis demonstrated that emodin induced cell cycle arrest at G0/G1 phase. Annexin V/PI double staining confirmed that emodin had no effect on cell apoptosis. AFM images revealed that the cell nuclear area was full and the surface of cell membrane was flat and smooth in control group. Compared with control group, the cell nuclear area collapsed and shrank in emodin group at 48 h. The cell membrane ultrastructure showed that the particles in emo-din group had an intensive distribution. The height of cell nuclear area was decreased, and the surface average roughness (Ra) and root mean square roughness (Rq) were elevated in emo-din group compared with control group. CONCLUSION: Emodin has cytotoxicity on MCF-7 cells via cell cycle arrest at G0/G1 phase and ultrastructural changes.     

Effects of artesunate on membrane surface morphology of human gastric cancer SGC-7901 cells observed under atomic force microscope

AIM: To detect the membrane surface morphology of cancer cells treated with artesunate (ART) under atomic force microscope (AFM). METHODS: Human gastric cancer SGC-7901 cells were cultured and treated with different concentrations of ART for 24 h. The membrane surface morphology, three-dimensional structures and ultrastructural changes of SGC-7901 cells were observed under AFM. The apoptosis of SGC-7901 cells was detected by flow cytometry. RESULTS: The AFM images revealed that the cell nuclear area was full and the surface of cell membrane was flat and smooth in control group. Compared with control group, the cell nuclear area collapsed and suffered atrophy, and the membrane surface had more pores in ART treatment groups. More pores were observed and the diameter of the pores was increased with the increase in ART concentration. The cell membrane ultrastructure showed that the particles in control group had an intensive distribution, some were cord-shaped and some gathered into a mass. The particles in ART treatment groups were fewer and distributed sparsely. Moreover, there were obvious lacunae in the surface of cell membrane. Quantitive measurement found that the height of cell nucleus area was decreased, and the surface root mean square roughness (Rq) and the surface average roughness (Ra) became smaller in ART treatment groups compared with control group. The apoptotic rates of the cells in ART treatment groups were increased with the increase in ART concentration, and were all significantly higher than that in control group. CONCLUSION: Our findings emphasize the significance of AFM in exploring the changes of the membrane surface morphology at nano-scale resolution following the treatment with anticancer drugs, which could not only identify the specific characteristics of morphological changes of the tumor cells, but also provide micromorphological references to reveal the mechanisms of anticancer drugs.     

矮化苹果负载量对氮素吸收、分配及利用的影响

以5年生‘烟富3’/M26/平邑甜茶为试材,采用~(15)N同位素示踪技术,研究不同负载量对氮素吸收、分配及利用的影响。结果表明:与高负载量[对照,单株留果量(120±8)个]相比,中负载量(2/3负载量)和低负载量(1/3负载量)植株的叶面积、叶绿素含量、叶片总氮量和单果质量显著增加,平均单果质量分别增加了19.02%和37.38%,但其平均单株产量却显著降低。3个处理各器官的Ndff值表现一致,果实的Ndff值最大,其次是一年生枝、叶片和根;随着负载量的增加,果实的Ndff值增大,一年生枝、叶片及根的Ndff值减小。高负载量、2/3负载量和1/3负载量单株总氮量和~(15)N利用率分别为65.85 g和19.59%、70.96 g和22.01%、92.67 g和26.13%;高负载量、2/3负载量和1/3负载量果实15N分配率分别为35.32%、18.18%和8.40%,一年生枝、叶片和根的~(15)N分配率则随着负载量的增加而减小。疏果(2/3负载量和1/3负载量)虽然降低单株产量但显著改善果实品质,显著提高氮肥利用率,综合效益,以2/3负载量,即单株留果量为(80±7)个最好。     

Effects of hypoxia exposure for different time on structure and function of red blood cells in rats

AIM: To investigate the effects of hypoxia exposure on the structure and function of erythrocytes in rats at different time. METHODS: Male SD rats (n=40) were randomly divided into 5 groups, normal control group, 1-week hypoxia group, 2-week hypoxia group, 3-week hypoxia group and 4-week hypoxia group, with 8 rats per group. The rats in hypoxia groups were placed in the simulated 5 800 m of high altitude in a hypobaric chamber for different time. The values of detected blood, erythrocyte deformation index, erythrocyte osmotic fragility, erythrocyte oxygen dissociation, erythrocyte apoptosis and bone marrow biopsy were determined. RESULTS: Compared with normal control group, the red blood cell count, hemoglobin content, mean corpuscular volume and mean corpuscular hemoglobin significantly increased (P<0.01). Eversion rate of phosphatidylserine of erythrocytes increased. Oxygen half-saturation of hemoglobin increased (P<0.05). Bone marrow erythroid proliferation increased. The erythrocyte deformation index and erythrocyte osmotic fragility decreased significantly (P<0.01). In addition, oxygen dissociation curves shifted to the right. CONCLUSION: In the early stage of hypoxia, compared with normal control group, the changes of erythrocyte structure and function increase the oxygen supply to the tissue and are conducive to adapting to the plateau. However, with the extension of hypoxia, excessive erythrocytosis results in thrombosis, microcirculation disturbance and aggravating tissue hypoxia.     

An oxidative injury model of human kidney epithelial cells

AIM: To establish an injured cell model using human kidney proximal tubule epithelial cell line (HKC) to mimic the oxidative injury by hydrogen peroxide (H₂O₂). METHODS: The cell viability, the content of malondialdehyde (MDA) in the culture supernatant and the activity of intracellular superoxide dismutase (SOD) were detected to investigate the degree of cell injury. Osteopontin (OPN) expressed on the cell membrane surface were observed by laser confocal microscopy before and after cell injury. The changes of cellular morphology and the ultrastructure of membrane surface were observed under scanning electronic microscope. RESULTS: After HKC cells were treated with H₂O₂ at the concentration of 1 mmol/L for different time, the cell viability and the activity of SOD decreased and the content of MDA increased. The expression level of OPN significantly increased and reached to maximae at 1 h. The injured cells appeared shriveled and rough surface, and the shedding of most flagellae was also observed. CONCLUSION: H₂O₂ induces severer injury in HKC cells, including not only the cell viability and membrane surface ultrastructure, but also the OPN expression on the membrane, which could bind calcium oxalate crystal. Therefore, treatment with H₂O₂ at the concentration of 1 mmol/L for 1 h can be used to establish an oxidative injury model in HKC cells.     

Effects of DSF/Cu on surface ultrastructures and mechanical properties of human breast cancer and normal breast epithelial cells

AIM: To study the effects of disulfiram/copper complex (DSF/Cu) on ultrastructures and mechanical properties of human breast cancer and normal breast epithelial cells by atomic force microscopy (AFM) based on the nanoscale resolution and piconewton force measurement level. METHODS: The change of cell cycle and apoptotic rate of MCF-7 cells and MCF-10A cells induced by DSF/Cu were compared by flow cytometry. The cell surface morphology, ultrastructure, height, width and roughness were detected by AFM. The effects of DSF/Cu on the hardness (Young's modulus) of the 2 kinds of cells were determined by AFM with indentation technique. RESULTS: DSF/Cu significantly induced apoptosis of the MCF-7 cells in a dose-dependent manner, whereas had little effect on the MCF-10A cells. The cell cycle analysis showed that DSF/Cu induced G₂/M arrest in the MCF-7 cells, but led to G₀/G₁ arrest in the MCF-10A cells. The AFM images showed that the MCF-7 cells shrank and showed smaller and smoother morphology, and the filopodia were retracted obviously, even some became into lamellipodia, or disappeared completely after treated with DSF/Cu at concentrations of 400 and 800 nmol/L. The quantitative analysis indicated that the MCF-7 cells showed smaller width and larger height, and the root mean square roughness and average roughness were decreased significantly in a dose-dependent manner after treated with DSF/Cu at concentrations of 400 and 800 nmol/L. However, little effect in the MCF-10A cells was observed. The biomechanics test at a single cell level demonstrated that the Young's modulus of the MCF-7 cells and MCF-10A cells were both increased, yet the proportion increased in the MCF-7 cells was much higher than that in the MCF-10A cells after treated with DSF/Cu at concentrations of 400 and 800 nmol/L. CONCLUSION: DSF/Cu has strong antitumor effect on breast cancer with high efficiency and low toxicity by changing the properties of the biomechanics specifically.     

Observation of molecular interaction between gold nanoparticle and VEGF165 with atomic force microscope

AIM: To investigate the molecular interaction between gold nanoparticles (GNP) and vascular endothelial growth factor 165(VEGF₁₆₅) under atomic force microscope (AFM). METHODS: Before and after incubation with VEGF₁₆₅, GNP were screened by integrated tools including AFM, ultraviolet-visible absorption spectroscopy and particle size analysis under near-physiological condition. In addition, GNP at different concentrations were incubated with VEGF₁₆₅, then added to starved human umbilical vein endothelial cells(HUVECs). The ultrastructural changes of HUVECs surface were examined by AFM. The effects of GNP on the growth of HUVECs were assessed by MTT assay. RESULTS: After treated with VEGF₁₆₅, the GNP absorption peak revealed a slight red shift, and the size distribution of GNP was increased from 20 nm to 30 nm. By AFM imaging, the diameter of GNP was (22.05±1.52) nm in average while the average diameter of GNP-VEGF₁₆₅ was (33.91±2.61) nm. Binding of GNP and VEGF₁₆₅, and the formation of GNP-VEGF₁₆₅ core-shell complex were indicated by the AFM imaging. AFM screening showed the changes of ultrastructure on HUVECs surface. The group of VEGF₁₆₅ displayed the signs of cell proliferation. Granulation of cell surface, increase in cell-to-cell contact, formation of pseudopodia and appearance of membranes pores were all observed. The proliferation of HUVECs was inhibited by GNP with MTT assay. CONCLUSION: GNP bind to VEGF₁₆₅ through chemical bonds to block or inactivate the receptor binding sites of VEGF₁₆₅. Therefore, GNP inhibit VEGF₁₆₅-induced proliferation of HUVECs.     

Effects of prenatal stress on neurons and neuronal ultrastructure of developing hippocampus in rats

AIM:To investigate the effects of prenatal stress (PS) on neurons and neuronal ultrastructure of hippocampus in offspring rats, and to explore the role of the overproduction of oxidants. METHODS:One month male offspring rats were obtained to observe the neuronal number, neuronal ultrastructure and the number of nNOS -positive cell in hippocampus. RESULTS:The neuronal number of CA1 and CA4 subregions in late gestation stress (LS) offspring decreases significantly. The neuronal ultrastructure of CA1 subregion in MS (stress in 7-13 days of gestation) and LS offspring appeared bulgy mitochondria, unclear membrane and irregular electron density. Lipofuscin pigments increased; The number of nNOS-positive cell in CA1, CA2, CA3 subregions and DG of MS group and the whole hippocampus of LS group increased significantly. CONCLUSION:PS damaged the neurons and neuronal ultrastructure of hippocampus of offspring rats. The damages were associated with the overproduction of oxidants.     

Effects of nicotine on ultrastructure and cytokine secretion of human periodontal ligamental fibroblasts

［ABSTRACT］AIM: To explore the effects of nicotine on surface morphology, ultrastructure, proliferation, cell cycle and cytokine secretion of human periodontal ligamental fibroblasts (PDLFs). METHODS: Before and after treatment with nicotine, the surface morphology and ultrastructure of PDLFs were observed under atomic force microscope and transmission electron microscope. The cell proliferation was examined by MTT assay. The cell cycle and apoptotic rate were determined by flow cytometry. The levels of basic fibroblast growth factor (bFGF), insulin-like growth factor I (IGF-I), transforming growth factor β1 (TGF-β1), intercellular adhesion molecule 1(ICAM-1), vascular cell adhesion molecule 1 (VCAM-1) and vasculr endothelial growth factor (VEGF) were detected by ELISA. RESULTS: After treatment with nicotine, pycnosis, vacuolation in the cytoplasm, and karyorrhexis were observed in the PDLFs. The rough endoplasmic reticulum expanded and mitochondria swelled. Cell proliferation was inhibited in a time- and dose-dependent manner. The cell number in G0/G1 phase increased while that in G2 phase and S phase decreased. The apoptotic rate and the rate of cycle arrest were increased with the increase in nicotine concentration. After treatment with nicotine, the secretion levels of bFGF and IGF-I declined, while the levels of ICAM-1, VCAM-1, TGF-β1 and VEGF increased. CONCLUSION: Nicotine changes the surface morphology and ultrastructure of PDLFs to apoptosis-like characters and inhibits the proliferation of the cells. Nicotine may affect the repairment of PDLFs by regulating the levels of cytokine secretion.     

Ultrastructure and function of human bone marrow mesenchymal stem cells

AIM: To study the cytoskeleton of mesenchymal stem cells (MSCs), the ultrastructure and function relationship by using atomic force microscope (AFM). METHODS: The ultrastructures and morphological feature of MSCs cultured for 1 d and 5 d were studied by AFM. RESULTS: The special structures that possess peculiar morphological characteristic of MSCs such as cytoskeleton, pseudopod, microfilament etc were identified by AFM, and these special structures are difficult to observe under electronic microscopy or other conventional optical microscopy. CONCLUSIONS: AFM is a powerful tool to study ultrastructures, morphological features, and cytoskeleton of stem cells in near physiological conditions. Its application prospect in cellular biology is extensive. The special cytoskeleton and other structures of MSCs observed above may represent the structural base of multi-differentiation potential of MSCs.     

Effect of hypertonic saline solution on the geometry of erythrocyte in rats subjected to hemorrhagic shock

AIM:To study the effect of hypertonic saline solution on the geometry of erythrocyte in hemorrhage-shocked rats,using micropippette aspiration technique. METHODS:Wistar rats were randomized into three groups of 0.9% NaCl(NS),7.5% NaCl(HS) and 5% NaCl-3.5% NaAc(HSA). The animals were bled to reach a mean arterial pressure of 5.3 kPa in 10 minutes and maintained in shock for 90 minutes. 4 mL/kg NS,HS or HSA was given intravenously and respectively in 5 minutes following hemorrhagic shock. The blood was collected to determine the geometry of erythrocyte at baseline,after shock and treatment. RESULTS:There were no significant difference in surface area/volume ratio and spherical index between baseline and shock.The diameter of erythrocyte were decreased obviously following hemorrhagic shock. The surface area/volume ratio was significantly lower in HS group than that in NS and HSA group after treatment. HS and HSA raised spherical index of erythrocyte remarkbly compared with NS.Otherwise,the spherical index of erythrocyte was reduced significantly in HSA group compared to HS group. Both HS and HSA decreased diameter of erythrocyte notably compared with NS. CONCLUSION:Both HS and HSA have deleterious effects on the geometry of erythrocyte in rats subjected to hemorrhagic shock.Whereas, HSA could decrease the side effect compared with HS.     

Mixed culture of human iPSCs with rabbit corneal endothelial cells induces differentiation of iPSCs

AIM:To investigate the morphology and protein expression of human induced pluripotent stem cells(iPSCs) in the mixed-culture environment with rabbit corneal endothelial cells(CECs) and to provide the experimental basis and the mechanism of iPSC differentiation into CECs. METHODS:Primary rabbit CECs were isolated with trypsin and subcultured. The human iPSCs were cultured and amplified by a feeder-free method and their characteristics were evaluated by Western blotting. iPSCs labeled with quantum dots of appropriate concentration were used to establish mixed-culture model with rabbit CECs. The morphology of iPSCs was evaluated by atomic force microscopy(AFM) and inverted microscopy. The protein expression of CD31, CD34, CD133 and aquaporin 1(AQP1) in iPSCs was tested by the method of immunofluorescence. RESULTS:The rabbit CECs were hexagonal and showed a typical cobblestone appearance. iPSCs grew in the cloning form, and 3 pluripotent proteins Oct4, Nanog and Sox2 were expressed positively. 1/4 suspension of iPSCs labeled with 10 nmol/L quantum dots and 60% confluence of rabbit CECs made best mixed culture for each other. Under AFM and inverted microscope, the volume of iPSC became bigger and the nuclear-cytoplasm ratio was decreased after 7 days of mixed culture. Some granular protrusions of the membrane were observed and the surface roughness of the cell membrane increased. The protein expression of CD31, CD34, CD133 and AQP1 in iPSCs was negative, while AQP1 was detected after mixed culture for 2 weeks. CONCLUSION:iPSCs morphologically change to endothelial-like cells after mixed culture with rabbit CECs and express the marker protein AQP1 of CECs at the same time.     

Study of experimental varicocele on cell apoptosis of epididymis in adolescent rats

AIM: To study the cell apoptosis and the change of microstructure and ultrastructure in epididymis with experimental varicocele (EVC) in rats. METHODS: Experimental varicocele model was induced by partial ligation of the left renal vein in adolescent Sprague-Dawley Wistar rats. Apoptotic cells were detected by in situ terminal deoxynucleotityl transferase-mediated dTUP nick end labeling (TUNEL) technique. The corpus epididymis of the rats was prepared for light and electron microscopic observation. The microstructure and ultrastructure of the epididymis were studied. RESULTS: There was certain proportion of apoptosis cells in epididymis cells in control rats. The incidence of apoptosis increased remarkably in experimental group than that in control group (P<0.01). Under light microscope, the main changes observed were epididymis’s duct shrinked and the blebbing appeared in the epithelial cells. With electron microscope, numerous large lysosomes, increased residual bodies, expanded the endoplasmic reticulum, clouding the mitochondrion’s spinal, the vacuole in the Golgi complex, and defected main cellular organelles were also observed. Beside nuclear membrane, nuclear chromatin dense, lump, the microvilli of the columnar epithelial cells were sparse and showed local defects. CONCLUSIONS: The experimental varicocele in adolescent rats lead to an increase in cell apoptosis, microstructure and ultrastructure lesions in the epididymis, which may be another important reason of infertility resulting from varicocele.     

Influence of Tangshen formula on endothelial function and hemorheology in diabetic nephropathy rats

ATM: To explore the influence of Tangshen formula (TS) on endothelial function and blood rheology in diabetic nephropathy (DN) rats. METHODS: The DN rat model was established by intravenous injection of low-dose (30 mg/kg) streptozotocin (STZ) after having the high-fat/high-glucose diets for one month. The animals were divi-ded into DN model group, TS group and valsartan group. Fasting blood glucose (FBG), serum total cholesterol (TC), serum triglyceride (TG), renal cortex blood flow and hemorheology were monitored. The content of von Willebrand's factor (vWF) and plasminogen activator inhibitor-1 (PAI-1) in the serum was determined by ELISA. RESULTS: Compared with normal group, FBG,TC,TG, vWF and PAI-1 were increased in DN model group (P<0.05), and no significant difference of FBG was observed. Compared with normal group, plasma viscosity, Casson viscosity, whole blood high/medium/low-shear viscosity, erythrocyte aggregation index, erythrocyte rigidity index and erythrocyte electrophoresis time were increased, and erythrocyte deformation index was decreased in DN model group (P<0.01). Compared with DN model group, plasma viscosity, Casson viscosity, whole blood high/medium/low-shear viscosity, erythrocyte aggregation index, erythrocyte rigidity index and erythrocyte electrophoresis time were decreased (P<0.05), but there was no significant difference for erythrocyte deformation index in TS group. Compared with normal group, the renal cortex microcirculation blood flow in DN model group was significantly decreased. Compared with DN model group, the renal cortex microcirculation blood flow was significantly increased in TS group (P<0.05), and no significant change in valsartan group was found.CONCLUSION: Tangshen formula plays a protective role in the kidney of diabetic rats by improving the blood rheology and endothelial function, thus ameliorating the renal cortex microcirculation blood flow in experimental diabetic rats.     

Effects of obstructive jaundice on enterocyte chloridion secretion in rats

AIM: To investigate the effects of obstructive jaundice (OJ) on enterocyte chloridion secretion in rats. METHODS: The OJ model of rats was set up. The rats were divided into OJ1 group and OJ2 group randomly. The animals in OJ1 group were sacrificed by exsanguination 7 days after operation and the rats in OJ2 group were sacrificed 14 days after operation. The Cl^- concentration in peripheral blood was detected. The epithelial cells in the terminal ileum mucosas were cultured in vitro. The concentration of intracellular Cl^- was detected by fluorospectrophotometry. The Cl^- current was measured by whole-cell patch clamp experiments. Western blotting was used to examine the change of voltage-gated Cl^- channel 2 protein (ClC-2) and the images were analyzed by image analysis system and statistical software quantitatively. RESULTS: The serum Cl^- concentration in OJ1 group and OJ2 group were obviously lower than that in control group . The intracellular Cl^- relative concentrations in OJ1 group and OJ2 group were higher than that in control group (3.14±0.38 and 3.55±0.47 vs 2.69±0.41,both P<0.05). The Cl^- current of normal epithelial cells displayed outward rectification, and transformed negative value into positive value following cell membrane depolarization. The Cl^- current was (-15.45±7.56) pA/pF and (5.85±0.81) pA/pF when voltage was -80 mV and 80 mV. The ranges of upgrade of absolute values of average electric current density in OJ groups were lower than those in control group (all P<0.05). Western blotting analysis showed that the ClC-2 protein generated a broad band about 90 kD. The average gradations of Western blotting images were lower in OJ groups than that in control group (0.20±0.04 and 0.19±0.06 vs 0.27±0.06, both P<0.05). However, no difference between the 2 OJ groups was observed (P>0.05). CONCLUSION: The chloridion secretion of intestinal epithelium is restrained in rats with OJ. The concentration gradient between exterior and interior of epithelial cells is decreased, and the Cl^- outward current is reduced. All of above are concerned with downregulation of ClC-2 protein in cell membrane.     

Effects of prostaglandin I2 on mesenteric microcirculation and property of hemorheology in rabbits with renal ischemia/reperfusion injury

AIM: To explore the effects of prostaglandin I2 (PGI2) on mesenteric microcirculation and hemorheology during renal ischemia/reperfusion (IR) injury. METHODS: 36 rabbits were randomly distributed into the sham operated group (sham group)， renal ischemia/reperfusion injury group (IR group) and PGI2+IR group（PGI2 group）. IR group received clamping for 60 min followed by 120 min of reperfusion. A microcircular microscope image analysis system was used to study the changes of mesenteric microcirculation and hemorheology at 60 min of ischemia and 120 min of reperfusion, respectively， while the blood samples were obtained for the measurement of hemorheological indexes. RESULTS: ① In IR group during the period of renal IR， the number of adhesive leukocytes and microthrombus， hemorrhage and hemorheological indexes such as blood viscosity， plasma viscosity， blood reduction viscosity， hematocrit， erythrocyte aggregation index， erythrocyte sedimentation rate， erythrocyte sedimentation rate K and plasma fibrinogen were significantly higher， while microvascular diameters， blood flow velocity and erythrocyte deformation index were significantly lower compared with sham group (P＜0.01 or P＜0.05). ② PGI2 5-40 ng·kg-1·min-1) affected the indexes of mesenteric microcirculation and hemorheology to different extent. In 10 ng·kg-1·min-1 PGI2 group， the diameters of arteriole and venule， blood flow velocity， the number of adhesive leukocytes， microthrombus， hemorrhage and hemorheological indexes significantly changed， compared with IR group (P＜0.01 or P＜0.05). Except that microvascular diameters increased remarkably （P＜0.01）， others showed no significant difference compared to sham group （P＞0.05）. CONCLUSIONS: PGI2 ameliorates the disturbance of mesenteric microcirculation and hemorheology caused by renal IR injury with the best effect at 10 ng·kg-1·min-1.