Through dog models of common bile duct obstruction (BDO), the contents of liver superoxide dismutase (SOD) and malondialdehyde(MDA) were measured 2,3,4 and 5 weeks after BDO. Results indicated that the hepatic MDA content was increased 2 weeks after BDO as compared with control group (Ｐ＜0.01), the hepatic SOD content was decreased 3 weeks after BDO (Ｐ＜0.05). When bile duct obstructing, these changed were more serious. The results suggest that liver has little ability to eliminate the superoxide free radicals after BDO, whereas the lipid peroxidation products increase. It may be one of the mechanisms of liver damage after BDO.
Objective To explore the potential protective effect in vivo of Edaravone, a free radical scavenger on model of acute lung injury in rats with sepsis. Methods Twenty-four male Wistar rats were randomly divided into three groups, ie. a control group( NS group) , a model group( LPS group) , a Edaravone treatment group( ED group) . ALI was induced by injecting LPS intravenously( 10 mg/ kg) in the LPS group and the ED group. Meanwhile the ED group was intravenously injected with Edaravone( 3 mg/ kg) . The NS group was injected with normal saline as control. The lung tissue samples were collected at 6 h after intravenous injection. The wet / dry ( W/D) weight ratio of lung tissue was measured. The levels of myeloperoxidase ( MPO) , malondialdehyde ( MDA ) and superoxide dismutase ( SOD) in lung tissue homogenate were assayed. The pathological changes and expression of nuclear factor-kappa B( NF-κB) in lung tissue were also studied. Results Compared with the NS group, The W/D, pathological scores, NF-κB expression, MPO and MDA levels in the LPS group were significantly higher( all P lt; 0. 01) , and the level of SOD was apparently lower( P lt; 0. 01) . The W/D, pathological scores, NF-κB expression, MPO and MDA levels in the ED group were significantly lower than those in the LPS group( all P lt; 0. 01) and higher than those in the NS group( all P lt; 0. 01) . And the level of SOD in lung tissue of the ED group was higher than that in the LPS group and lower than that in the NS group ( P lt; 0. 01) . Conclusions Edaravone has protective effect on ALI rat model. The mechanismmay be related to its ability of clearing the reactive oxygen species, inhibiting the activation of the signal pathway of NF-κB and inflammatory cascade.
Objective To investigate the protective effects of endotoxin pretreatment on lung injury of rats with endotoxemia. Methods The rat model of acute endotoxemia was established by injecting lipopolysaccharide (LPS) intraperitoneally. Seventy-two male Wistar rats were randomly divided into three groups, ie. a saline control group (N, n=24) , a LPS-treated group (L, n=24) , and a LPS pretreated group ( P, n=24) . Each group was divided into 2 h, 4 h, 6 h, and 12 h subgroups. The rats in group P were firstly administered with introperitoneal injection of 0.25 mg/kg LPS. After 24 hours, they were subjected to the injection of 0.5 mg/kg LPS. The rats in group N and L received injection of equivalent amount of saline. After 72 hours, the rats in group L and P were challenged with intravenous injection of 10 mg/kg LPS, otherwise saline in group N. Six rats were killed at 2, 4, 6 and 12 hours respectively after injection of LPS in group L and P. The lungs were removed for detecting intercellular adhesion molecule-1 ( ICAM-1) , superoxide dismutase ( SOD) , and malondialdehyde (MDA) . Meanwhile the level of tumor necrosis factoralpha ( TNF-α) in serum was measured, and the pathological changes of lung were also examined. Results The contents of ICAM-1, MDA and TNF-α in the LPS-treated 4 h group were 75.07 ±0. 53, ( 3.93 ± 0.42) μmol/g, and (478.62 ±45.58) pg/mL respectively, significantly higher than those in the saline control group. The endotoxin pretreatment reduced the above indexes to 42.40 ±0.44, ( 2.89 ±0.49) μmol / g and ( 376.76 ±43.67) pg/mL respectively (Plt;0.05) . The content of SOD in the LPS-treated 4 h group was ( 6.26 ±0.31) U/mg, significantly lower than that in the saline control group. The endotoxin pretreatment increased SOD to ( 8.79 ±0.35) U/mg. Conclusion Endotoxin pretreatment can suppress the progress of lung injury in rats with endotoxemia and protect the lung tissue by down-regulating the inflammatory response and oxygen free radical production.
Objective To study the effect of various doses of estrogen on tissue injury, blood supply and survival area of skin flap and to investigate its mechanism. Methods Thirty New Zealand white rabbits aged 3-4 months old and weighing 1.5-2.2 kg (male or female) were used. Random pattern skin flap (12 cm × 3 cm in size) taking the central l ine of the rabbit dorsum as axis and with the pedicle attached at the proximal end was prepared, and the flap pedicle division was performed 7 days after operation. The rabbits were divided randomly into three groups (n=10 rabbits per group). At 2, 4, and 6 days after operation, the proximal edge of flap in group A and B received 100 ?g/kg and 50 ?g/kg subcutaneous injection ofestradiol benzoate, respectively, while group C received no further treatment serving as control group. General condition ofthe rabbits was observed after injection, gross observation was performed 3 and 7 days after injection, survival area of the skin flap was measured 7 days after injection, contents of malondialdehyde (MDA) and nitric oxide (NO) were tested 5 days after injection, and the flaps were harvested 4 and 7 days after injection to receive histology and no significant difference was noted between group A and group B (P gt; 0.05). The NEU counts 4 days after injection were (18.20 ±6.24) cells/HP in group A, (21.27 ± 5.34) cells/HP in group B, and (28.78 ± 7.92) cells/HP in group C, and at 7 days after injection, there were (15.16 ± 7.02) cells/HP in group A, (18.12 ± 6.44) cells/HP in group B, and (29.67 ± 9.12) cells/HP in group C. The VEGF score 4 days after injection was (4.02 ± 0.48) points in group A, (4.19 ± 0.66) points in group B and (3.67 ± 0.49) points in group C, and at 7 day after injection, it was (4.96 ± 0.69) points in group A, (5.12 ± 0.77) points in group B, and (3.81 ± 0.54) points in group C. Significant difference was evident between 4 days and 7 days after injection in group A or B in terms of NEU counts and VEGF score (P lt; 0.05), and difference between 4 days and 7 days after injection in group C was not significant (P gt; 0.05), and the differences among 3 groups were significant (P lt; 0.05). Conclusion Estrogen injection can increase VEGF expression and NO content of flap, decrease MDA content and NEU infiltration of flat, and improve survival area of flap.
Objective To explore the effect of oxygen inhalation on the retinae of newborn rats and its mechanism.Methods We mimicked the retinopathy of prematurity(ROP) by putting the newborn rats in high concentrated oxygen. One-day old rats were put into the oxygen box with the oxygen concentration of 80% for continuous 7 days; then in air condition for 7 days. The arterial blood oxygen pressure, retinal superoxide dismutase (SOD), and malondialdehyde (MDA) of the rats (1,2,4,7,8,9,11,14 days old) were examined. The diameter of retinal vessels′main branch and the coverage rate of peripheral vessels were measured in 7- and 14-day-old rats by ink perfusion. The retinal neovascularization of rats (8,9,11, 14 days old) were observed by HE staining. The rats of the same age fed in air condition were in the control group.Results The differential pressures of blood oxygen of rats (1,2,4,7 days old) in study group were significantly higher than those in the control group (P＜0.01), while the differential pressures of blood oxygen of rats (8,9,11,14 days old) in study group were lower than those in the control group (P＞0.05). The contents of SOD of the retinae in the rats ( 1,2,4,7,8 days old) were significantly lower than those in the control group(P＜0.01, P＜0.05 ), while the contents of MDA were significantly higher than those in the control group (P＜0.01,P＜0.05). The diameter of retinal vessels′main branch in 7-day rats was 75% of the control group, and the coverage rate of peripheral vessels was 22% of the control group; and was 61% and 73% respectively in 14-day-old rats. The neovascularization could be seen in 16.7% of the rats in the study group and nought in the control group.Conclusion The damage of free radical of the retina in high concentrated oxygen and hypoxia situation after oxygen supply may be one of the most important mechanism of ROP. (Chin J Ocul Fundus Dis，2003，19：269-332)
Objective To investigate the effect of advanced glycation end products (AGEs) on the catalase activity and the levels of malondialdehyde in cultured bovine retinal capillary pericytes (BRPs), and to investigate the relationship between oxidative stress and diabetic retinopathy. Methods Cultured BRPs were exposed to AGEs (0, 8, 32, 125, 500, 2 000 μg/ml) for four days. Activity and the levels of catalase and malondialdehyde in cultured BRPs were examined by spectrophotometry. Results AGEs decreased the catalase activity, whereas increased the levels of malondialdehyde of cultured BRPs in a dose-dependent manner (r=-0.714, r=0.748, P＜0.01).There were significant differences between BRPs cultured in 32 μg/ml AGEs and in control group (P＜0.01), while no significant differences between BRPs cultured in non-glycated bovine serum albumin and absence of bovine serum albumin were found. Conclusion Oxidative stress may be one of the reasons why the pericyte disappears in diabetic retinopathy. (Chin J Ocul Fundus Dis, 2002, 18: 143-145)
Objective：To observe the histochemical changes of retinal photochemical damage in rats. Methods：The changes of retinal ultrastructure were observed.The concentration of malondaldehyde(MDA) was tested and the activity the histochemical change of cytochrome oxidase (CCO) and (Mg ++ -ATPasw) were evaluated on the retnal photochemical damage in SD rats. Results：At the 6th hour after light exposure,the swelling appwared at the nuclei of photoreceptor,the mitochondria of inner segment.The apical microvilli of RPE disappeared and lysosomes increased in RPE.On the 6th day after light exposure,the changes became more obvious.While on the 14th day after light expose the nuclei of photoreceptors and the inner segments renewed but the arrangement of the disk was lose;and the microvilli appeared of the disk was lose;and the microvilli appeared at the tip of RPE.The Activity of CCO and Mg ++ -ATPase decreased and MDA increased in retina at the 6th hour and on the 6th day and they recovered on the 14th day after light exposure. Conclusion：Lipd peroxidation that broke the cell membrane system of photoreceptor which induced changes of the cell ultrastru cture abd the activity of enzyme might relate to pathogenesis in retinal photochemical damage. (Chin J Ocul Fundus Dis,1998,14:38-40)
PURPOSE: To probe the effect of taurine on lipid peroxidation,surperoxide dismutase(SOD) and glutathione peroxidase(GSH-Px)in retina in vitro. METHODS: The animal eye cups were put into media(divided into four groups:control,model,taurine and beta;-carotene) respectively,and incubated at 37deg;C in a humidified atmosphere of 5% CO2/95% air. After 24h or 48h ,the retinas were taken out from the media and the SOD,GSH-Px ,protein and malondialdehyde(MDA) were examined. RESULTS:Taurine could inhibite lipid peroxidation in retina ,decrease MDA level ,could not protect GSH-Px activity in retina. The effect of taurine on SOD activity in retina was also uncertain. CONCLUSION:Taurine can inhibit lipid peroxidation in retina in vitro,but the mechanism of that has nothing to do with the effect of taurine on SOD activity and GSH-Px activity. （Chin J Ocul Fundus Dis,1996,12: 183-185 ）
【Abstract】 Objective To investigate the protective role of recombinant human growth hormone (rhGH )in ischemic reperfusion injury of rat liver and its mechanism. Methods One hundred Male rats were randomly divided into two groups: the rhGH group and the control group. In the rhGH group, rhGH were injected （0.2U/100g weight） to rats seven days before the ischemic reperfusion injury, and in the control group, normal saline was injected instead. Serum levels of ALT， TNF-α and IL-1α were tested. Hepatic tissue was sectioned for to detect the level of EC and MDA, the expression of NF-κB and ICAM-1 mRNA on SEC. Ultrastructural characteristics histopathological characteristics were determined also. Results Serum levels of ALT, TNF-α, IL-1α and the contents of MDA in the control group were significantly higher than those in the rhGH group （P＜0.05）. Comparied with control group, rhGH also decreased NF-κB activation, and reduced the expression of ICAM-1 mRNA of SEC in the liver cells （P＜0.05）. Electronic microscopic revealed that the hepatic sinusoidal endothelial cells and the hepatocellular mitochondria were injured in the control group. Pretreatment with the rhGH was able to significantly improved the pathological changes. Conclusion rhGH might confer the protection to ischemic reperfusion injury of rat liver through reducing the expression of NF-κB to down-regulate cytokine (IL-1α,TNF-α), MDA and inhibition the expression of ICAM-1 mRNA.
【Abstract】Objective To investigate the protective effects of epidermal growth factor (EGF) on pancreas of rats with acute pancreatitis(AP). Methods Seventytwo male SpragueDawley rats were randomly divided into 3 groups: Control group, AP group and AP-EGF group. Subcutaneously injection of EGF (0.1 μg/g) were given to animals in the AP-EGF group after the establishment of the model of AP. The other two groups of animals received the same volume of saline. At 6 h, 12 h and 24 h after induction of AP, 8 animals in each group were sacrificed respectively， 4 ml of blood sample was withdrawn from heart，2 ml for the analysis of amylase activity and 2 ml for MDA content in serum. Ascites was sucked with dry gauzes and was weighed thereafter. Changes of pancreas morphology were evaluated at every time point. The same part of pancreas was removed for measurement of MDA content, apoptotic index (AI) and histologic changes. Results Histologic injury of the animals in the APEGF group was milder than that in the AP group. Ascites weight in the AP-EGF group decreased significantly compared with that in the AP group at 12 h and 24 h 〔(4.53±1.29) g vs (6.58±1.47) g, (7.64±1.85) g vs (11.96±2.13) g，P＜0.05，P＜0.01〕. Amylase activity in the APEGF group also decreased significantly compared with that in the AP group at 12 h and 24 h 〔(142.0±8.3) U/L vs (187.9±10.4) U/L, (194.3±10.4) U/L vs (253.3±8.6) U/L, P＜0.05，P＜0.01〕. MDA content in plasm 〔(2.34±0.23) μmol/L vs (3.15±0.38) μmol/L, P＜0.05〕 and in pancreas 〔(5.21±1.46) μmol/g vs (7.68±1.63) μmol/g, P＜0.01〕 in the APEGF group decreased significantly compared with those in the AP group at 24 h. AI of pancreas in the APEGF group increased significantly compared withthatintheAPgroupafteroperation〔(16.22±3.53)%〖KG4vs (7.35±1.04)%, (11.67±2.40)% vs (4.81±0.86)%, (6.38±1.42)% vs (1.97±0.21)%, P＜0.01〕. Conclusion EGF may accelerate the restoration of pathologic injury and alleviate the hemorrhage and edema of pancreas. It may also depress MDA content in plasm and in pancreas so that to lessen oxidative damage. EGF may protect pancreas by inducing cellular apoptosis.