Objective To investigate the effect of ischemic preconditioning on chaperone hsp70 expression and protein aggregation in the CA1 neurons of rats, and to further explore its potential neuroprotective mechanism. Methods...Objective To investigate the effect of ischemic preconditioning on chaperone hsp70 expression and protein aggregation in the CA1 neurons of rats, and to further explore its potential neuroprotective mechanism. Methods Two-vesseloccluded transient global ischemia rat model was used. The rats were divided into sublethal 3-min ischemia group, lethal 10- min ischemia group and ischemic preconditioning group. Neuronal death in the CA1 region was observed by hematoxylineosin staining, and number of live neurons was assessed by cell counting under a light microscope. Immunochemistry and laser scanning confocal microscopy were used to observe the distribution of chaperone hsp70 in the CA1 neurons. Differential centrifuge was used to isolate cytosol, nucleus and protein aggregates fractions. Western blot was used to analyze the quantitative alterations of protein aggregates and inducible chaperone hsp70 in cellular fractions and in protein aggregates under different ischemic conditions. Results Histological examination showed that ischemic preconditioning significantly reduced delayed neuronal death in the hippocampus CA1 region （P 〈 0.01 vs 10-min ischemia group）. Sublethal ischemic preconditioning induced chaperone hsp70 expression in the CA1 neurons after 24 h reperfusion following 10-min ischemia. Induced-hsp70 combined with the abnormal proteins produced during the secondary lethal 10-min ischemia and inhibited the formation of cytotoxic protein aggregates（P〈0.01 vs 10-min ischemia group）.Conelusion Ischemic preconditioning induced chaperone hsp70 expression and inhibited protein aggregates formation in the CA1 neurons when suffered secondary lethal ischemia, which may protect neurons from death.展开更多
目的 :构建人血管内皮生长因子 ( VEGF) c DNA逆转录病毒表达质粒。方法 :采用 PCR方法从 pc DNA- VEGF165质粒中扩增 VEGF165基因 ,在序列两端分别引入 Eco R 和 Bam H 限制性内切酶识别位点 ,并克隆到逆转录病毒表达载体 p LXSN质粒...目的 :构建人血管内皮生长因子 ( VEGF) c DNA逆转录病毒表达质粒。方法 :采用 PCR方法从 pc DNA- VEGF165质粒中扩增 VEGF165基因 ,在序列两端分别引入 Eco R 和 Bam H 限制性内切酶识别位点 ,并克隆到逆转录病毒表达载体 p LXSN质粒中。结果 :酶切鉴定、PCR扩增以及DNA序列分析表明已经将 VEGF165基因全长序列克隆到逆转录病毒表达载体 p LXSN质粒中 ,获得了 p LXSN- VEGF165重组质粒。结论 :成功地构建了人 VEGF c DNA逆转录病毒表达质粒 ,为进一步临床应用 VEGF c展开更多
基金the grants from the Department of Science and Technology of Jilin Province, China (No. 20070721)the Bureau of Science and Technology of Changchun, Jilin Province, China (No. 2007129).
文摘Objective To investigate the effect of ischemic preconditioning on chaperone hsp70 expression and protein aggregation in the CA1 neurons of rats, and to further explore its potential neuroprotective mechanism. Methods Two-vesseloccluded transient global ischemia rat model was used. The rats were divided into sublethal 3-min ischemia group, lethal 10- min ischemia group and ischemic preconditioning group. Neuronal death in the CA1 region was observed by hematoxylineosin staining, and number of live neurons was assessed by cell counting under a light microscope. Immunochemistry and laser scanning confocal microscopy were used to observe the distribution of chaperone hsp70 in the CA1 neurons. Differential centrifuge was used to isolate cytosol, nucleus and protein aggregates fractions. Western blot was used to analyze the quantitative alterations of protein aggregates and inducible chaperone hsp70 in cellular fractions and in protein aggregates under different ischemic conditions. Results Histological examination showed that ischemic preconditioning significantly reduced delayed neuronal death in the hippocampus CA1 region （P 〈 0.01 vs 10-min ischemia group）. Sublethal ischemic preconditioning induced chaperone hsp70 expression in the CA1 neurons after 24 h reperfusion following 10-min ischemia. Induced-hsp70 combined with the abnormal proteins produced during the secondary lethal 10-min ischemia and inhibited the formation of cytotoxic protein aggregates（P〈0.01 vs 10-min ischemia group）.Conelusion Ischemic preconditioning induced chaperone hsp70 expression and inhibited protein aggregates formation in the CA1 neurons when suffered secondary lethal ischemia, which may protect neurons from death.
文摘目的 :构建人血管内皮生长因子 ( VEGF) c DNA逆转录病毒表达质粒。方法 :采用 PCR方法从 pc DNA- VEGF165质粒中扩增 VEGF165基因 ,在序列两端分别引入 Eco R 和 Bam H 限制性内切酶识别位点 ,并克隆到逆转录病毒表达载体 p LXSN质粒中。结果 :酶切鉴定、PCR扩增以及DNA序列分析表明已经将 VEGF165基因全长序列克隆到逆转录病毒表达载体 p LXSN质粒中 ,获得了 p LXSN- VEGF165重组质粒。结论 :成功地构建了人 VEGF c DNA逆转录病毒表达质粒 ,为进一步临床应用 VEGF c
