脳血管攣縮と脂質過酸化反応—クモ膜下出血患者の髄液中に発生する脂質過酸化物の分析

CEREBRAL VASOSPASM AND LIPID PEROXIDATION:LIPID PEROXIDES IN THE CEREBROSPINAL FLUID AFTER SUBARACHNOID HEMORRHAGE

　抄録　クモ膜下出血患者より経時的に採取した髄液中の脂質成分を高速液体クロマトグラフィー（HPLC）とガスクロマトグラフィー・マススペクトロメトリー（GC-MS）にて分析し，髄液中での過酸化脂質の生成と脳血管攣縮発生の関連について検討した。経過中に脳血管攣縮の発生が確認された患者から採取した髄液の脂質画分をHPLCにかけ238nmで検出したところ，脳血管攣縮の発生時期に一致して数個のピークの出現が認められた。これらのピークのうち，HPLCにおける相対保持時間がアラキドン酸酸化物標準サンプルと正確に一致するピークを分取し，GC-MSで分析した。その結果，髄液中に5—hydroxy eicosa—tetraenoic acid （5—HETE）が生成されていることが判明した。10例のクモ膜下出血患者から経時的に採取した髄液の脂質画分をHPLC （238nm）で分析し，5—HETEのピーク高を計測して臨床経過と対応させて検討したところ，5—HETEの生成と脳血管攣縮発生に明らかな相関性が認められた。以上の結果は，脂質過酸化反応が脳血管攣縮の発生に関与していることを裏付けるものである。

The relationship between lipid peroxides in cerebrospinal fluid (CSF) and the occurrence of cerebral vasospasm following subarachnoid hemorrhage (SAH) was evaluated by analyzing CSF with high-performance liquid chromatography (HPLC) and gas chromatography mass spectrometry (GC -MS). Hydroperoxy eicosatetraenoic acids (HPETEs) and hydroxy eicosatetraenoic acids (HETEs) were synthesized by the treatment of arachidonic acid with hydrogen peroxide and cupric chloride. The retention time of these HPETEs and HETEs were determined on HPLC. The position of oxydation occurred was determined after methylation, reduction and trimethyl silyla-tion using GC-MS. Thus the elucidation of positional isomers of HI'ETEs and HETEs was made possible by the retention time on HPLC.

The supernant of CSF after SAH was adjusted to pH 3. 0 and then absorbed to octadecyl silyl silica column. The eluted fraction with 15% ethanol-water from octadecyl silyl silica column was analyzed by HPLC detecting at 238 nm. No peak was observed on HPLC at the region of HPETEs and HETEs in the CSF obtained from healthy person. In SAH patients, several peaks were recognized in accordance with the occurrence of cerebral vasospasm. One of the peaks was identified as 5-HETE by HPLC and GC-MS.

In 10 SAH patients, semi-quantitative analysis of 5-HETE in the CSF was performed by mea-suring the height of the peak identified as 5- HETE on HPLC. The close correlation was recognized between the occurrence of cerebral vasospasm and the appearance of 5-HETE in the CSF.

The results of the present study suggest that lipid peroxidation is involved in the pathogenesis of chronic vasospasm after SAH.