缺氧对15-脂氧酶同工酶在肺动脉中表达的影响

目的比较15-脂氧酶的两种同工酶:15-lipoxygenase-1(15-LO-1),15-lipoxygenase-2(15-LO-2)在正常对照组和慢性缺氧组中肺动脉表达的差异,从而探讨两种同工酶在缺氧性肺血管收缩中的作用。方法18只SD大鼠随机分为两组(n=9),正常对照组和缺氧组。通过动物乏氧箱建立大鼠慢性缺氧模型。分别用免疫组化法、原位杂交法、Western blot法比较两种同工酶在两组中表达的差异。结果①15-LO-1在正常对照组肺动脉有蛋白质的表达,而15-LO-2在正常对照组蛋白质水平不表达。②缺氧时15-LO-1蛋白质表达明显强于在正常对照中的表达(P<0.01)。③缺氧时15-LO-2在蛋白质水平表达,但15-LO-1蛋白质水平表达强于15-LO-2。④15-LO-1,15-LO-2在正常对照组和慢性缺氧组均有mRNA水平的表达,而且在缺氧组中的表达高于对照组。结论缺氧同时诱导15-LO-1,15-LO-2在肺动脉中表达增加,从而使二者在缺氧性肺血管收缩中发挥一定作用。

Expression of 15-Lipoxygenase isoenzymes in the pulmonary arteries during hypoxia

Aim The purpose of this study was to compare the differential expression of 15-lipoxygenase isoenzymes in the pulmonary arteries between normoxia and hypoxia and to explore their roles in the formation of hypoxic pulmomary vasoconstriction. Method Eighteen SD rats were randomly divided into two groups(n=9):the normoxic control group breathing fresh gas and the hypoxic group breeding in animal hypoxic incubator.Immunohistochemical method,in situ hybridization and Western blot were employed to determine certain 15-lipoxygenase isoenzymes which involved in the process of hypoxic pulmonary vasoconstriction.Results ①In normoxic control group,the expression of 15-LO-1 protein was detected in the pulmonary arteries;but the expression of 15-LO-2 protein wasn’t detected.②The expression of 15-LO-1 protein in hypoxic group was much stronger than that in normoxic group (P<0.01).③The expression of 15-LO-2 protein was detected during hypoxia and the expression of 15-LO-1 protein was stronger than that of 15-LO-2 protein.④ Both 15-LO-1 and 15-LO-2 mRNA were expressed in normoxic and hypoxic group.And the expression of them in hypoxic group was much stronger than that in normoxic group.Conclusion Hypoxia upregulates both of the expressionof 15-LO-1 and 15-LO-2 in the pulmonary arteries,which may lead to play a role in hypoxic pulmonary vasoconstriction.