AIM: Peroxynitrite (ONOO-) is a powerful oxidant shown to damage membranes. In the present study, the effect of taurine on changes of liver plasma membrane Na+, K+-ATPase induced by ONOO- was investigated. METHODS: Li...AIM: Peroxynitrite (ONOO-) is a powerful oxidant shown to damage membranes. In the present study, the effect of taurine on changes of liver plasma membrane Na+, K+-ATPase induced by ONOO- was investigated. METHODS: Liver plasma membrane was exposed toONOO-with or without taurine. Na+, K+-ATPase activity and lipid peroxidation as thiobarbituric acid reactive substances (TBARS) levels were measured.RESULTS: Different concentrations of ONOO- (100, 200,500, and 1 000 μmol/L) were found to decrease liver plasma membrane Na+, K+-ATPase activity significantly. The depletion of enzyme activity was not concentration dependent. Effects of different concentrations of taurine on liver plasma membrane Na+, K+-ATPase activity were also measured. Taurine did not cause any increase in enzyme activity. When plasma membranes were treated with 200 μmol/L ONOO- with different concentrations of taurine, a restoring effect of taurine on enzyme activity was observed. TBARS levels were also measured and taurine was found to decrease the elevated values. CONCLUSION: Taurine is observed to act as an antioxidant of ONOO-to decrease lipid peroxidation and thus affect liver plasma membrane Na+, K+-ATPase by restoring its activity.展开更多
AIM:To explore a simple method to create intestinal autotransplantation in rats and growing pigs and to investigate the effect of L-arginine supplementation on serum nitric oxide (NO), nitric oxide synthase (NOS) and ...AIM:To explore a simple method to create intestinal autotransplantation in rats and growing pigs and to investigate the effect of L-arginine supplementation on serum nitric oxide (NO), nitric oxide synthase (NOS) and intestinal mucosal NOS and Na+-K+-ATPase activity during cold ischemia-reperfusion (IR) in growing pigs. METHODS: In adult Wistar rat models of small bowel autotransplantation, a fine tube was inserted into mesenteric artery via the abdominal aorta. The superior mesenteric artery and vein were occluded. Isolated terminal ileum segment was irrigated with Ringer's solution at 4℃ and preserved in the same solution at 0-4℃ for 60 min. Then, the tube was removed and reperfusion was established. In growing pig models, a terminal ileum segment, 50 cm in length, was isolated and its mesenteric artery was irrigated via a needle with lactated Ringer's solution at 4℃. The method and period of cold preservation and reperfusion were described above. Ten white outbred pigs were randomly divided into control group and experimental group. L-arginine (150 mg/kg) was continuously infused for 15 min before reperfusion and for 30 min after reperfusion in the experimental group. One, 24, 48, and 72 h after reperfusion, peripheral vein blood was respectively collected for NO and NOS determination. At the same time point, intestinal mucosae were also obtained for NOS and Na+-K+-ATPase activity measurement. RESULTS: In adult rat models, 16 of 20 rats sustained the procedure, three died of hemorrhage shock and one of deep anesthesia. In growing pig models, the viability of small bowel graft remained for 72 h after cold IR in eight of 10 pigs. In experimental group, serum NO level at 1 and 24 h after reperfusion increased significantly when compared with control group at the same time point (152.2±61.4μmol/L /s60.8±31.6μmol/L, t=2.802, P=0.02<0.05; 82.2±24.0μmol/L vs 54.0±24.3μmol/L, t=2.490, P=0.04<0.05). Serum NO level increased significantly at 1 h post-reperfusion when compared with the same group before cold IR, 24 and 48 h post-reperfusion (152.2±61.4μmol/L vs 75.6±16.2μmol/L,t=2.820, P=0.02<0.05,82.2±24.0μmol/L,t=2.760, P= 0.03<0.05, 74.2±21.9μmol/L, t=2.822, P= 0.02<0.05). Serum NOS activity at each time point had no significant difference between two groups. In experimental group, intestinal mucosal NOS activity at 1 h post-reperfusion reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.46±0.12 U/mg, t = 3.460, P= 0.009<0.01). Mucosal NOS activity at 24, 48, and 72 h post-reperfusion also reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.57±0.14 U/mg, t= 2.380, P=0.04 <0.05, 0.61±0.11 U/mg, t= 2.309, P = 0.04<0.05, 0.63±0.12U/mg, t = 2.307, P= 0.04<0.05). In control group, mucosal NOS activity at 1 and 24 h post-reperfusion was significantly lower than that in pre-cold IR (0.72±0.12 U/mg vs 0.60±0.07 U/mg, t= 2.320, P= 0.04<0.05, 0.58±0.18 U/mg, t=2.310, P= 0.04<0.05). When compared to the normal value, Na+-K+-ATPase activity increased significantly at 48 and 72 h post-reperfusion in experimental group (2.48±0.59μmol/mg vs 3.89±1.43μmol/mg, t=3.202, P= 0.04<0.05, 3.96±0.86μmol/mg, t=3.401, P= 0.009 <0.01) and control group (2.48±0.59μmol/mg vs 3.58±0.76 μmol/mg, t=2.489, P= 0.04<0.05, 3.67±0.81μmol/mg, t= 2.542, P= 0.03<0.05). CONCLUSION: This novel technique for intestinal autotransplantation provides a potentially consistent and practical model for experimental studies of graft cold preservation. L-arginine supplementation during cold IR may act as a useful adjunct to preserve the grafted intestine.展开更多
目的探讨精氨酸抗利尿激素(AVP)对急性肺损伤肺水肿液清除作用。方法 48只健康成年的雄性SD大鼠随机分为对照组、模型组(ALI组)、AVP组,观察各组肺组织病理形态学、肺水含量、肺泡上皮通透性及肺泡液体清除率(AFC)变化,测定肺泡上皮钠通...目的探讨精氨酸抗利尿激素(AVP)对急性肺损伤肺水肿液清除作用。方法 48只健康成年的雄性SD大鼠随机分为对照组、模型组(ALI组)、AVP组,观察各组肺组织病理形态学、肺水含量、肺泡上皮通透性及肺泡液体清除率(AFC)变化,测定肺泡上皮钠通道(ENa C)和钠/钾ATP酶(Na+,K+-ATPase)表达情况。结果经AVP治疗后,模型组肺泡上皮通透性(0.27±0.15 vs0.59±0.19)及肺水含量(5.01±1.59 vs 8.67±1.79)减轻,AFC增加(23.56±4.51 vs 8.28±3.57),α-ENa C(1.296±0.322 vs 0.349±0.141)和α1-Na+,K+-ATPase表达增加(1.421±0.389 vs 0.338±0.186),均有显著差异(P<0.05)。结论 AVP能促进AFC,其作用途径可能是上调α-ENa C和α1-Na+,K+-ATPase通道蛋白实现的。展开更多
基金Supported by the Istanbul University Research Foundation,No.BYP-247/20082003
文摘AIM: Peroxynitrite (ONOO-) is a powerful oxidant shown to damage membranes. In the present study, the effect of taurine on changes of liver plasma membrane Na+, K+-ATPase induced by ONOO- was investigated. METHODS: Liver plasma membrane was exposed toONOO-with or without taurine. Na+, K+-ATPase activity and lipid peroxidation as thiobarbituric acid reactive substances (TBARS) levels were measured.RESULTS: Different concentrations of ONOO- (100, 200,500, and 1 000 μmol/L) were found to decrease liver plasma membrane Na+, K+-ATPase activity significantly. The depletion of enzyme activity was not concentration dependent. Effects of different concentrations of taurine on liver plasma membrane Na+, K+-ATPase activity were also measured. Taurine did not cause any increase in enzyme activity. When plasma membranes were treated with 200 μmol/L ONOO- with different concentrations of taurine, a restoring effect of taurine on enzyme activity was observed. TBARS levels were also measured and taurine was found to decrease the elevated values. CONCLUSION: Taurine is observed to act as an antioxidant of ONOO-to decrease lipid peroxidation and thus affect liver plasma membrane Na+, K+-ATPase by restoring its activity.
基金Supported by the Natural Scientific Foundation of Shandong Province,No.Q99C13
文摘AIM:To explore a simple method to create intestinal autotransplantation in rats and growing pigs and to investigate the effect of L-arginine supplementation on serum nitric oxide (NO), nitric oxide synthase (NOS) and intestinal mucosal NOS and Na+-K+-ATPase activity during cold ischemia-reperfusion (IR) in growing pigs. METHODS: In adult Wistar rat models of small bowel autotransplantation, a fine tube was inserted into mesenteric artery via the abdominal aorta. The superior mesenteric artery and vein were occluded. Isolated terminal ileum segment was irrigated with Ringer's solution at 4℃ and preserved in the same solution at 0-4℃ for 60 min. Then, the tube was removed and reperfusion was established. In growing pig models, a terminal ileum segment, 50 cm in length, was isolated and its mesenteric artery was irrigated via a needle with lactated Ringer's solution at 4℃. The method and period of cold preservation and reperfusion were described above. Ten white outbred pigs were randomly divided into control group and experimental group. L-arginine (150 mg/kg) was continuously infused for 15 min before reperfusion and for 30 min after reperfusion in the experimental group. One, 24, 48, and 72 h after reperfusion, peripheral vein blood was respectively collected for NO and NOS determination. At the same time point, intestinal mucosae were also obtained for NOS and Na+-K+-ATPase activity measurement. RESULTS: In adult rat models, 16 of 20 rats sustained the procedure, three died of hemorrhage shock and one of deep anesthesia. In growing pig models, the viability of small bowel graft remained for 72 h after cold IR in eight of 10 pigs. In experimental group, serum NO level at 1 and 24 h after reperfusion increased significantly when compared with control group at the same time point (152.2±61.4μmol/L /s60.8±31.6μmol/L, t=2.802, P=0.02<0.05; 82.2±24.0μmol/L vs 54.0±24.3μmol/L, t=2.490, P=0.04<0.05). Serum NO level increased significantly at 1 h post-reperfusion when compared with the same group before cold IR, 24 and 48 h post-reperfusion (152.2±61.4μmol/L vs 75.6±16.2μmol/L,t=2.820, P=0.02<0.05,82.2±24.0μmol/L,t=2.760, P= 0.03<0.05, 74.2±21.9μmol/L, t=2.822, P= 0.02<0.05). Serum NOS activity at each time point had no significant difference between two groups. In experimental group, intestinal mucosal NOS activity at 1 h post-reperfusion reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.46±0.12 U/mg, t = 3.460, P= 0.009<0.01). Mucosal NOS activity at 24, 48, and 72 h post-reperfusion also reduced significantly when compared with pre-cold IR (0.79±0.04 U/mg vs 0.57±0.14 U/mg, t= 2.380, P=0.04 <0.05, 0.61±0.11 U/mg, t= 2.309, P = 0.04<0.05, 0.63±0.12U/mg, t = 2.307, P= 0.04<0.05). In control group, mucosal NOS activity at 1 and 24 h post-reperfusion was significantly lower than that in pre-cold IR (0.72±0.12 U/mg vs 0.60±0.07 U/mg, t= 2.320, P= 0.04<0.05, 0.58±0.18 U/mg, t=2.310, P= 0.04<0.05). When compared to the normal value, Na+-K+-ATPase activity increased significantly at 48 and 72 h post-reperfusion in experimental group (2.48±0.59μmol/mg vs 3.89±1.43μmol/mg, t=3.202, P= 0.04<0.05, 3.96±0.86μmol/mg, t=3.401, P= 0.009 <0.01) and control group (2.48±0.59μmol/mg vs 3.58±0.76 μmol/mg, t=2.489, P= 0.04<0.05, 3.67±0.81μmol/mg, t= 2.542, P= 0.03<0.05). CONCLUSION: This novel technique for intestinal autotransplantation provides a potentially consistent and practical model for experimental studies of graft cold preservation. L-arginine supplementation during cold IR may act as a useful adjunct to preserve the grafted intestine.
文摘目的探讨精氨酸抗利尿激素(AVP)对急性肺损伤肺水肿液清除作用。方法 48只健康成年的雄性SD大鼠随机分为对照组、模型组(ALI组)、AVP组,观察各组肺组织病理形态学、肺水含量、肺泡上皮通透性及肺泡液体清除率(AFC)变化,测定肺泡上皮钠通道(ENa C)和钠/钾ATP酶(Na+,K+-ATPase)表达情况。结果经AVP治疗后,模型组肺泡上皮通透性(0.27±0.15 vs0.59±0.19)及肺水含量(5.01±1.59 vs 8.67±1.79)减轻,AFC增加(23.56±4.51 vs 8.28±3.57),α-ENa C(1.296±0.322 vs 0.349±0.141)和α1-Na+,K+-ATPase表达增加(1.421±0.389 vs 0.338±0.186),均有显著差异(P<0.05)。结论 AVP能促进AFC,其作用途径可能是上调α-ENa C和α1-Na+,K+-ATPase通道蛋白实现的。
