Effect of leukotriene antagonist on experimental delayed cerebral vasospasm.

Experimental delayed cerebral vasospasm was produced in 16 adult mongrel dogs by the "two-hemorrhage" method of intracisternal injections of autologous arterial blood. Group 1 was a control group. Group 2 was a treatment group that received an intravenous injection of ONO-1078, a novel potent leukotriene antagonist, once a day for 7 days just after the first cisternal injection of the blood. Angiography was performed on Days 0 and 7, and the cerebrospinal fluid levels of leukotriene C4 (LTC4) were measured on Days 0, 3, and 7. The cisternal levels of LTC4 increased after subarachnoid hemorrhage in both groups. But the cerebrospinal fluid levels of LTC4 in the treatment group were significantly lower than those in the control group (P less than 0.05). The angiographic vasospasm after subarachnoid hemorrhage was partially prevented with the treatment of intravenous injections of ONO-1078 (P less than 0.001). These results suggest that LTC4 may play a role in the pathogenesis of delayed cerebral vasospasm, directly or indirectly, and ONO-1078 may have a therapeutic effect on the prevention of the development of delayed cerebral vasospasm.