A study on cisternal CSF levels of arachidonic acid metabolites after aneurysmal subarachnoid hemorrhage

Abstract

Arachidonic acid (AA) metabolites may play an important role in the pathogenesis of cerebral vasospasm which complicate subarachnoid hemorrhage. Authors have studied levels of 4 major AA metabolites in lumbar CSF samples and in CSF collected from perianeurismatic cisterns of 40 patients admitted with diagnosis of subarachnoid hemorrhage. Lumbar levels of AA metabolites are significantly higher in SAH patients than in control cases; moreover, cisternal CSF levels of PGD 2, TxB 2 and LTC 4 are significantly higher than lumbar levels. Cisternal CSF levels (expressed in pg/ml ± SEM) are in the “spasm” group: PGD 2: 1129.62 ± 146.33; 6-keto-PGF 1 α : 214.2 ± 19.96; TxB 2: 4350.25 ± 656.87; LTC 4: 2582.19 ± 381.83. In the “no spasm” group: PGD 2 460.1 ± 55.89; 6-keto-PGF 1 α : 306.37 ± 88.74; TxB 2: 5752.5 ± 899.25; LTC 4: 812.92 ± 142.06. Statistical analysis (paired t-test) shows values significantly higher for cisternal levels of PGD 2 ( P < 0.005) and LTC 4 ( P < 0.005) in patients presenting vasospasm. This suggests the importance of the subarachnoidal clot as a source of vasoactive compounds. Higher levels of leukotriene C 4 in patients presenting vasospasm suggest a role for the compound in the genesis of local inflammatory processes and morphological changes of the arterial wall.