目的探讨Rho激酶抑制剂Y-27623对心肌缺血再灌注损伤(MIRI)中细胞凋亡的影响,以及对丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)和凋亡相关蛋白表达水平的变化和意义.方法成年雄性SD大鼠60只,应用随机数字表法分为4组,...目的探讨Rho激酶抑制剂Y-27623对心肌缺血再灌注损伤(MIRI)中细胞凋亡的影响,以及对丝裂原活化蛋白激酶(mitogen-activated protein kinase,MAPK)和凋亡相关蛋白表达水平的变化和意义.方法成年雄性SD大鼠60只,应用随机数字表法分为4组,每组15只:正常对照组(Sham组)、缺血再灌注组(ischemia-reperfusion,I/R组)、Dil组(Diltiazem,地尔硫卓组)和Y-27632组.Dil组每日给予地尔硫卓(10 mg/kg)灌胃,Y-27632组每日给予Y-27632(5 mg/kg),其余两组给予等体积清水.给药5天后Sham组只穿线,不结扎冠状动脉左前降支,I/R组、Dil组和Y-27632组均建立MIRI模型.TUNEL法检测各组心肌凋亡,计算心肌细胞凋亡指数(AI),western blotting法检测心肌组织中MAPK信号传导途径相关蛋白(p-JNK/ERK/P38)和凋亡相关蛋白(Bcl-2、Bax、Caspase-3和Caspase-9)的表达.结果相对于Sham组,I/R组AI明显增加(35.15±3.12比1.15±0.12,P<0.01),MAPK信号传导途径(p-JNK:0.792±0.071比0.344±0.055;p-ERK:0.809±0.087比0.273±0.055;p-P38:0.781±0.049比0.158±0.071)和心肌促凋亡相关蛋白(Bax:1.127±0.060比0.47±0.054;Caspase-3:0.843±0.092比0.289±0.068;Caspase-9:0.831±0.068比0.273±0.048)表达显著增加(P均<0.05),心肌抗凋亡蛋白Bcl-2表达显著减少(0.255±0.060比0.809±0.056,P<0.05);相对于I/R组,Y-27632治疗组AI明显下降(20.05±1.75比35.15±3.12,P<0.01),与Dil治疗组差异无统计学意义(20.05±1.75比22.12±2.01,P>0.05),Y-27632治疗组MAPK信号传导途径相关蛋白(p-JNK:0.443±0.027比0.792±0.344;p-ERK:0.284±0.038比0.809±0.087;p-P38:0.301±0.049比0.781±0.049)和Bax(0.807±0.072比1.127±0.060)、Caspase-3(0.329±0.040比0.843±0.092)和Caspase-9(0.454±0.048比0.831±0.068)表达均显著降低(P<0.05),Bcl-2表达显著增加(0.582±0.048比0.255±0.060,P<0.05),与Dil治疗组差异无统计学意义(p-JNK:0.443±0.027比0.552±0.044;p-ERK:0.284±0.038比0.273±0.049;p-P38:0.301±0.049比0.339±0.038;Bax:0.807±0.072比0.645±0.108;Caspase-3:0.329±0.040比0.378±0.096;Caspase-9:0.454±0.048比0.434±0.032;Bcl-2:0.582±0.048比0.614±0.06,P均>0.05).结论Y-27632通过抑制JNK/ERK/P38的磷酸化,抑制Bax、Caspase-3和Caspase-9的表达,加强Bcl-2的表达,减少心肌细胞的凋亡,从而减轻心肌缺血再灌注损伤.展开更多
A facile preparation of nitrogen-doped β-TiO2（N-doped β-TiO2） nanobelts and their visible-light photocatalytic activity were reported.The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange betwe...A facile preparation of nitrogen-doped β-TiO2（N-doped β-TiO2） nanobelts and their visible-light photocatalytic activity were reported.The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange between layered sodium titanate nanobelts and NH 4 ＋ in aqueous solution at room temperature and subsequent calcination in air.Such a calcination treatment is beneficial to the formation of monoclinic N-doped β-TiO2 nanobelts.Various measurement results indicate that not only were the nitrogen atoms doped into the lattice of β-TiO2 nanobelts resulting in a strong visible-light absorption,but also a large number of defects were caused by them in the lattice,increasing the stability of β-TiO2.The photocatalysis enhancement of N-doped β-TiO2 nanobelts for the photodegradation of Rhodamine B was demonstrated.展开更多
基金Supported by the National Basic Research Program of China(No.2006CB932605)the National Natural Science Foundation of China(No.20876002)the Fund of Beijing Technology and Business University for the Talent,China
文摘A facile preparation of nitrogen-doped β-TiO2（N-doped β-TiO2） nanobelts and their visible-light photocatalytic activity were reported.The preparation of N-doped β-TiO2 nanobelts consisted of cation-exchange between layered sodium titanate nanobelts and NH 4 ＋ in aqueous solution at room temperature and subsequent calcination in air.Such a calcination treatment is beneficial to the formation of monoclinic N-doped β-TiO2 nanobelts.Various measurement results indicate that not only were the nitrogen atoms doped into the lattice of β-TiO2 nanobelts resulting in a strong visible-light absorption,but also a large number of defects were caused by them in the lattice,increasing the stability of β-TiO2.The photocatalysis enhancement of N-doped β-TiO2 nanobelts for the photodegradation of Rhodamine B was demonstrated.
