Relationship between endothelin-1 and nitron oxygen changes in cerebral spinal fluid and cerebral vasospasm following subarachnoid hemorrhage

Objective To investigate the relationship between endothelin-1(ET-1)and NO in cerebral spinal fluid(CSF) and cerebral vasospasm(CVS) following experimental subarachnoid hemorrhage(SAH).Methods An experimental CVS model was achieved by twice injections of fresh autologous arterial blood into the cisterna magna of each animal. The contents of ET-1 and NO in CSF were measured by radioimmunological analysis and activated cadmium reduction method respectively.The degrees of CVS were analyzed through cerebral angiography(%reduction of basilar artery diamiter,%RBAD). Results The contents of ET-1 in CSF increased significantly than that before injection after SAH(P 0.05) and decreased gradually after reaching the highest level of 215± 36 μg/L on 7 th day. Mean while,the contents of NO in CSF decreased significantly than that before injection (P 0.05) and increased gradually after reaching the lowest level of 5.8± 1.35 μmol/L on 7th day.The degrees of CVS became serious after SAH and relieved gradually after reaching the most serious degree of 48±10 on 7th day.Conclusions CVS degrees make a close correlation with ET-1 and NO content changes in CSF on differrent stage as well as on the levels. ET-1 and NO in CSF may be involved in the process of CVS following experimental SAH.