Occurrence of oxidized metabolites of arachidonic acid esterified to phospholipids in murine lung tissue.
Occurrence of oxidized metabolites of arachidonic acid esterified to phospholipids in murine lung tissue.
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DOI：
10.1006/abio.1998.2749
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发表时间：
1998-08
影响因子：
2.9
通讯作者：
Tatsuji Nakamura;Peter M. Henson;Robert C. Murphy
中科院分区：
文献类型：
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作者：
Tatsuji Nakamura;Peter M. Henson;Robert C. Murphy
小鼠肺磷脂的分离和鉴定表明，10种异压二十烷类化合物正常存在，对应于将一个氧原子掺入到酯化为甘油磷脂的花生四烯酸中。取小鼠肺，提取脂类，分离成游离羧酸和磷脂。在分析之前，磷脂被水解以产生游离羧酸。以d8-二十碳四烯酸(D8-HETE)为内标，采用反相高效液相色谱和电喷雾串联质谱法对6个单羟基二十碳四烯酸(HETE)和4个环氧二十碳四烯酸(EET)区域异构体进行了鉴定和定量。气管内注射tBuOOH(36 mg/kg)后，HETEs酯化为磷脂的数量增加，但酯化EETs水平无明显变化。对酯化的15-HETE进行了手性分析，R/S为0.96，表明这种单羟基花生四烯酸磷脂的生成是通过自由基机制进行的，tBuOOH处理小鼠肺后，R/HETE的对映体比为1.10。这些结果与含有花生四烯酸的肺甘油磷脂的氧化自由基机理是一致的。
Isolation and characterization of murine pulmonary phospholipids revealed the normal occurrence of 10 isobaric eicosanoids corresponding to the incorporation of one oxygen atom into the arachidonate esterified to glycerophospholipids. Lungs from mice were removed and lipids were extracted and then separated into free carboxylic acid and phospholipids. Phospholipids were hydrolyzed to yield the free carboxylic acids prior to analysis. Reverse-phase HPLC and electrospray tandem mass spectrometry were used to identify and quantitate six monohydroxyeicosatetraenoic (HETE) and four epoxyeicosatetraenoic (EET) acid regioisomers using d8-HETE as internal standard. HETEs esterified to phospholipids were found to increase following intratracheal administration of tBuOOH (36 mg/kg), but not the levels of esterified EETs. Chiral analysis of esterified 15-HETE revealed an R/S ratio of 0.96, suggesting operation of a free radical mechanism responsible for generation of this monohydroxy arachidonate phospholipid, and this enantiomeric ratio was 1.10 following treatment of the mouse lung with tBuOOH. These results are consistent with a free-radical-based mechanism of oxidation of pulmonary glycerophospholipids containing arachidonate.