Lipid peroxidation and PAFacetylhydrolase activity of cerebrospinal fluid in patients with subarachnoid hemorrhage

我们试图比较SAH后有和无症状性血管痉挛（SVS）患者的血浆PAF-AH活性和脑脊液（CSF）中脂质过氧化生物标志物的游离形式。用Western blotting法检测CSF中PAF-AH的表达。测定血浆PAF-AH基因第279位的基因型。测定CSF中PAF-AH活性和游离8-iso-PGF_（2α）（游离isoPs）、游离羟基十八碳二烯酸（游离HODE）、游离羟基二十碳四烯酸（游离HETE）水平。CSF中PAF-AH仅为血浆型。血浆PAF-AH基因型在SVS组与非SVS组间无差异。SAH后0-4天和5-9天，无SVS的患者的游离isoPs、游离HODE和游离HETE值较高。SAH后0- 4d和5- 9d无SVS者PAF-AH活性亦明显增高。PAF-AH活性与游离isoPs、游离HODE之间存在显著相关性，SAH时CSF中活性氧自由基产生的脂蛋白和血细胞膜氧化脂质可能是脂质过氧化的主要来源。血浆PAF-AH可水解氧化磷脂，减轻脂质过氧化反应，参与SAH后血管痉挛的防御机制

We attempt to compare plasma PAF-AH activity and free forms of bio-marker of lipid peroxidation in cerebrospinal fluid (CSF) between patients with and without symptomatic vasospasm (SVS) after SAH. The identification of PAF-AH in CSF was performed by Western blotting. The genotype at position 279 of the plasma PAF-AH gene was determined. The activities of PAF-AH and the levels of free 8-iso-PGF_<2α> (free isoPs), free hydroxyoctadecadienoic acid (free HODE), and free hydroxyeicosatetraenoic acid (free HETE) in CSF were measured. The PAF-AH in CSF was confirmed to be only the plasma type. The genotype of the plasma PAF-AH was not different between patients with and without SVS. Free isoPs, free HODE, and free HETE showed higher values in patients without SVS in 0-4 days and 5-9 days after SAH. The PAF-AH activity also showed higher in patients without SVS in 0-4 days and 5-9 days after SAH. The associations between PAF-AH activity and free isoPs, and between PAF-AH activity and free HODE were significant.Oxidized lipids of lipoproteins and blood cell membranes produced by reactive oxygen species in CSF when SAH occurs may be the main source of lipid peroxidation. Plasma PAF-AH can hydrolize oxidized phospholipids, and may attenuate the spreading of lipid peroxidation and participate in defense mechanism against vasospasm after SAH