【摘要】 为了进一步阐明高原鼢鼠和高原鼠兔对低氧环境的适应机制,应用分子生物学和免疫组化技术研究低氧环境对高原鼢鼠和高原鼠兔肝脏组织中VEGFxxx剪切体的组成、VEGFxxx剪切体mRNA表达水平以及微血管密度的影响。研究结果表明,低海拔(3 200 m)和高海拔(4 200 m)的高原鼢鼠肝脏组织中VEGF188,VEGF164,VEGF144和VEGF120都有表达,而低海拔的高原鼠兔肝脏组织中表现为VEGF189,VEGF165和VEGF121,高海拔的高原鼠兔肝脏组织中只有VEGF189和VEGF165有表达。随着海拔的升高,高原鼢鼠肝脏组织中VEGF188,VEGF164和VEGF120的表达水平和高原鼠兔肝脏组织中VEGF189和VEGF165的表达水平都没有显著性差异,但是在高海拔的高原鼠兔肝脏组织中VEGF121几乎不表达。随着海拔的升高,高原鼢鼠和高原鼠兔肝脏组织中VEGFxxx剪切体mRNA表达水平没有显著性变化,但是微血管密度有所升高,提示低氧增强VEGF mRNA的稳定性。无论是高海拔环境,还是低海拔环境,高原鼢鼠肝脏组织中VEGF188,VEGF164和VEGF120表达水平和微血管密度都高于高原鼠兔,这表明低氧可以上调VEGFxxx的表达,从而促进组织微血管的生长。更多还原

【Abstract】 To further clarify the adapting mechanisms of the zokor and pika to the hypoxic environments,we have explored the effects of the hypoxic environments on the constitution of VEGFxxxsplice variants,mRNA levels of the splice variants and the microvessel density( MVD) in livers of the zokor and pika by molecular technology and immunohistochemistry methods. The results indicated that VEGF188,VEGF164,VEGF144 and VEGF120expressed in the zokor either at elevation of 3 200 m or4 200 m,while VEGF189,VEGF165 and VEGF121expressed in the pika at elevation of 3 200 m,and VEGF189 and VEGF165expressed in that at elevation of 4 200 m; VEGF188,VEGF164,and VEGF120 expression levels had not significant increase with increasing of elevations in liver of plateau zokor,and VEGF189 and VEGF165expression levels had not significant decrease in liver of pika. However,VEGF121 mRNA was undetectable in the pika liver at elevation of 4 200 m. The mRNA expressionlevels of VEGFxxxsplice variants had no difference,but the microvessel densities in liver of the zokors and pikas increased with elevations. It suggested that hypoxia enhances the stability of VEGF mRNA.In the zokor liver,the MVD and the expression levels of VEGF188,VEGF164,and VEGF120 increased either at elevation of 3 200 m or at elevation of 4 200 m compared with those of pika. Our results indicated hypoxia up- regulated VEGFxxxgene expression and VEGFxxxpromoted microvessel growth.更多还原