常压低氧下Wistar大鼠脑组织中HIF-1α表达与脑损伤

Expression of HIF-1α and Brain Damage in Wistar Rat under Normobaric Hypoxia Condition

研究了常压低氧条件下Wistar大鼠脑组织中HIF-1α表达及脑损伤。设计了短期和长期低氧两种模式。短期急性低氧模式中,成年Wistar大鼠被随机分为4组:6%、8%、10%低氧组和常压常氧组。各组在上述氧气浓度条件下暴露2h;长期急性低氧在6%氧气浓度下每天低氧2h、连续低氧暴露10d。使用免疫组织化学和蛋白质印迹方法对低氧诱导因子HIF-1α在模型鼠脑组织内表达进行了表征,考察了低氧暴露强度、抗体稀释度对低氧诱导因子HIF-1α表达的影响;并应用HE染色法对脑组织的病理损伤进行了研究。实验结果证实,HIF-1α属于对低氧环境敏感的、低丰度的DNA结合蛋白,表达于脑组织核蛋白提取液中。高的低氧暴露强度和较低的一抗稀释度有利于HIF-1α表征。HE染色表明经6%急性低氧暴露2h处理后,模型鼠脑组织有损伤,海马神经细胞出现散在性单个坏死现象。

To study the expressions of Hypoxia Inducible Factor-1α and brain damage in Wistar rat brain,two different modes,short- and long-term hypoxia,were designed. Under short-term hypoxia mode,adult Wistar rats （160 ～ 180g） were randomly divided into four groups,which named 6% ,8% ,10% hypoxia group and normobaric normoxia group. Rats were exposed to hypoxia for 2h at various concentrations of oxygen. Control rats were exposed for 2h to normobaric normoxia. In long-term hypoxia mode,rats were exposed to hypoxia （6% O2 ） for 2h per day within the period of 10 days. Then effects of hypoxic expose degree and first antibody dilution were studied followed by HIF-1α expression analysis using immunohistochemistry and Western blot method. Brain damage was evaluated by using hematoxylin and eosin stain method. Results showed that HIF-1α,as a hypoxic-sensitive nucleoprotein,is a low-abundance DNA-binding protein. HIF-1α expression in nucleoprotein extraction of Wistar rat brain was observed via immunohistochemistry and Western-blot method. Higher degree of hypoxic exposure and lower dilution of first antibody enhanced the positive expression rates of HIF-1α. There were some necrotic features in rat hippocampal gyrus neuron cells after exposed to acute hypoxia （6% O2 ） for 2h.