不同间歇低氧方式对内皮细胞c-fos mRNA表达水平的影响

【摘要】目的 测定不同程度、频率间歇低氧（IH）条件下，人脐静脉内皮细胞即刻早期基因c-fos mRNA的表达水平。方法在自制细胞培养舱中程控产生预制的IH/ROX（再氧和）暴露环境，将内皮细胞暴露于该环境共60次循环，分为A、B、C组，每组包括5个小组。A组分正常氧组、标准孵箱对照组、持续低氧（CH）组、1.5%O2 IH组、10%O2 IH组。B、C组分别为1.5%O2，10%O2的不同IH频率组，低氧时间均为15s，循环次数均为60次，ROX时间不同，总循环时间不同，分别为1.5h组、3h组、5h组、6.5h组、9.5h共5个小组。采用Real-time PCR方法测定c-fos mRNA的表达水平。结果正常氧组与CH组的c-fos mRNA表达水平差异无统计学意义。1.5%O2 IH组、10%O2 IH组c-fos mRNA表达水平均高于正常氧组，且1.5%O2 IH组高于10%O2 IH组（P<0.01）。IH程度相同，随着ROX时间延长，c-fos mRNA表达水平均呈现先逐渐增加，后逐渐下降的规律，5h组c-fos mRNA表达水平明显高于其余各组（P<0.01）。结论 IH/ROX暴露可诱导内皮细胞即刻早期基因c-fos mRNA表达，这一过程与IH程度及频率密切相关。

Changes of c-fos mRNA in Endothelial Cells Exposed to Various Intermittent Hypoxia

Abstract]Objective To measure the mRNA expression of immediate-early gene c-fos in endothelial cells by theuse of different intermittent hypoxia (IH) protocols.MethodsA gas control delivery system was homemade, which produced IH/ re-oxygenation(ROX) environmental exposure. The endothelial cells were exposed to IH/ROX cycles, and were divided into three groups (A, B and C). There were five sub-groups in each group. Group A included intermittent normoxia group, standard incubator control group, continuous hypoxia group (CH),1.5%O2 IH group and10%O2 IH group. There were different frequency IH of1.5%O2 and10%O2sub-groups in group B and group C. Hypoxia time was15s. The intermittent hypoxia cycle was60and the ROX time was different. The total cycle time was different, including1.5h group,3h group,5h group,6.5h group and9.5h group. The mRNA expression of immediate-early gene c-fos was measured by real-time PCR.ResultsThere was no significant difference in the level of c-fos mRNA between intermittent normoxia group and CH group. The expression of c-fos mRNA was significantly higher in1.5%O2 IH group and10%O2 IH group than that of intermittent normoxia group, and there was a higher expression level of c-fos mRNA in 1.5%O2 IH group than that of 10%O2 IHgroup (P<0.01). It was found that the mRNA expression of c-fos increased gradually at first, and then gradually decreased. The expression of c-fos mRNA was significantly higher in5h group than that of other groups (P<0.01).ConclusionThe mRNA expression of immediate-early gene c-fos is increased after exposing to IH/ROX in endothelial cells, which isclosely related with IH extents and frequencies.