Background Research determined that hypoxia inducible factor-1(HIF-1)is associated with the hypoxia response in normal organ,and it plays an important role during the embryon development.It is also proved that the expression of vascular endothelial growth factor(VEGF)is upregulated in embryon retina.But,whether the action of HIF-1 and VEGF is correlated is unclear. Objective The aim of this study was to investigate the dynamic change of expression of HIF-1α and VEGF in retina during embryonic development and explore the role of HIF-1α and VEGF along with retinal evolvement.Methods The different embryon ages of SD rats were obtained from 30 clean pregnant SD rats by cesarean surgery.The retinas were isolated from embryon 10一day,12一day,14-day,16-day and 20-day rats respectively.The expressions of HIF-1 α and VEGF protein in retina were semi-quantitatively and qualitatively determined by immunochemistry,and the expressions of HIF-l α and VEGF mRNA in retina with different-embryon-phase and adult rats were detected by RT-PCR. Results The hishly level of expression of HIF-1 α and VEGF protein were found in the cellular nuclei and cytoplasm of retina in embryon 10一and 12-day rats.With the increase of embryon age.the expression of HIF-1α and VEGF protein in retina lowed(F=56.70,P<0.01；F=60.78.P<0.01).Compared with the adult rats,the expressions of HIF-1α and VEGF protein in retina were higher from embryon 0-day through 20-day rats(all P<0.01).The significantly positive correlation was found in the expression level between HIF-1α and VEGF protein throughout the experimental duration(r=0.96,P=0.00).Followed the same pattern,the expression levels of HIF-1α and VEGF mRNA in retinas were also enhanced in the embryon 10- and 12-day rats.Identically,a gradually weakened trend was seen in the expressions of HIF-1 α and VEGF mRNA in retinas as the increase of gestational age of rats(F=68.84,P<0.01；F=96.49,P<0.01),and the exDressions of HIF-1 α and VEGF mRNA decreased in the adult rats compared with different embryon-phase rats,showing a statistically significant difference between them(all P<0.01). Conclusion The expressions of HIF-1 αand VEGF in retina appear a dynamic alteration from hish to low during the embryonic development of rat retina,indicating that HIF-1α/VEGF pathway might participate in the process of embryo development of rat retina.%背景 研究发现低氧诱导因子-1(HIF-1)与机体缺氧的生理反应有关,并在胚胎发育过程中发挥作用.此外人视网膜胚胎发育过程中血管内皮生长因子(VEGF)呈高表达.但二者在胚胎期缺氧环境中的作用及相互关系仍有待研究.目的 观察大鼠视网膜胚胎发育过程中HIF-1α和VEGF的表达变化,探讨HIF-1a和VEGF在视网膜胚胎发育过程中的作用和相互关系.方法 30只清洁级SD孕鼠剖腹取出胚胎10、12、14、16、20 d鼠,每组取5只孕鼠,每只孕鼠随机选取2只胎鼠进行观察.摘除胎鼠一侧眼球,分离视网膜并制备切片,用免疫组织化学法检测视网膜组织中HIF-1α、VEGF蛋白的阳性表达,采用逆转录聚合酶链反应(RT-PCR)法分别检测不同胎龄大鼠及成年大鼠视网膜组织中HIF-1a mRNA及VEGF mRNA的表达.结果 免疫组织化学染色表明,在大鼠视网膜胚胎早期(10～12 d)即可检测到HIF0-α和VEGF蛋白均呈高表达,二者的表达强度均随胎龄的增加而减弱(F=56.70,P＜0.01;F=60.78,P＜0.01),各胎龄组视网膜中HIF-1a和VEGF蛋白的表达量均明显高于成年鼠,差异均有统计学意义(P＜0.01),随胎龄的增加HIF-1α蛋白在视网膜中的表达变化与VEGF蛋白表达呈正相关(r=0.96,P=0.00).RT-PCR检测结果表明,大鼠胚胎早期(10～12 d)即可检测到HIF-1a mRNA和VEGF mRNA在视网膜中均呈高表达,二者的表达均随胎龄的增加而减弱(F=68.84,P＜0.01;F=96.49,P＜0.01),各胎龄组视网膜中HIF-1α和VEGF蛋白的表达量均明显高于成年鼠,差异均有统计学意义(P＜0.01).结论大鼠视网膜胚胎发育过程中HIF-1α及VEGF的表达随着胎龄的增加均呈先高后低的动态变化趋势,提示HIF-1a/VEGF通路参与大鼠视网膜的胚胎发育过程.
展开▼
