ABSTRACT
<p><b>AIM</b>To determine the protective effect of ONO-1078, a leukotriene receptor antagonist, on focal cerebral ischemia induced by endothelin-1 in rats.</p><p><b>METHODS</b>Slow microinjection of endothelin-1 (120 pmol in 6 microL, for > 6 min) into the region near the middle cerebral artery was used to induce focal cerebral ischemia. ONO-1078 (0.1 mg.kg-1) was i.p. injected 1 h before endothelin-1 injection. Neurological symptoms, brain edema, brain infarction size, and the survival neurons in cortex and striatum were observed 24 h after ischemia.</p><p><b>RESULTS</b>Intracerebral microinjection of endothelin-1 induced remarkable neurological symptoms, brain infarction, brain edema, and decrease of survival neurons in the cortex and striatum. In rats pretreated with ONO-1078, endothelin-1-induced brain edema and brain infarction size were decreased. The numbers of survival neurons in striatum and cortex were increased significantly. The neurological symptoms were improved but not significantly.</p><p><b>CONCLUSION</b>ONO-1078 possesses neuroprotective effect against cerebral ischemic injury induced by endothelin-1, therefore, leukotrienes may play a role in the injury of cerebral ischemia.</p>