[Cerebral vasospasm and lipid peroxidation--lipid peroxides in the cerebrospinal fluid after subarachnoid hemorrhage]

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 silylation using GC-MS. Thus the elucidation of positional isomers of HPETEs 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 measuring 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.