Endothelin-1 levels in plasma and cerebrospinal fluid of patients with cerebral vasospasm after aneurysmal subarachnoid hemorrhage

Abstract

Background Plasma and cerebrospinal fluid (CSF) concentrations of endothelin-1 (ET-1) were measured in patients with subarachnoid hemorrhage (SAH) after aneurysmal rupture and compared with levels of ET-1 in volunteers. We analyze the relationship between levels of ET-1 in both CSF and plasma with the risk of developing cerebral vasospasm (CVS). Methods Cerebrospinal fluid and blood samples were collected from 30 selected patients after SAH and from 10 healthy volunteers who were used as control. All samples were stored at −70°C and the levels of ET-1 in CSF and blood were measured by using enzyme-linked immunosorbent assay and Western blot. All patients were submitted to angiography to confirm vasospasm. Results From the 30 patients admitted at different days of SAH, 18 (60%) developed clinical CVS and 10 (33%) presented angiographic CVS. The levels of ET-1 in the CSF were significantly higher ( P = .0001) in patients (1.618 ± 1.05 fmol/mL) than in controls (0.365 ± 0.328 fmol/mL). There was statistical difference ( P < .05) in CSF levels of ET-1 between each group of the Hunt-Hess scale and controls. The mean plasma concentration of ET-1 was similar ( P > .05) in the control group (1.531 ± 0.753 fmol/mL) and in patients with SAH (1.920 ± 1.15 fmol/mL). Conclusions These findings indicate that a significant rise in ET-1 levels in the CSF, but not in the plasma, occurs in patients who develop CVS after SAH. Our observation suggests that ET-1 might be involved in the pathogenesis of SAH-associated CVS.