[Subarachnoid administration of lidocaine reduces delayed neuronal damage due to forebrain ischemia in rats]

We examined the effect of subarachnoid administration of lidocaine on delayed neuronal damage due to forebrain ischemia in rats. Sixteen rats were divided at random into two groups: lidocaine group rats (n = 8) and control group rats (n = 8) were subarachnoidally administrated lidocaine 5mg.kg-1 and normal saline, respectively, prior to ischemia. Forebrain ischemia was induced by bilateral carotid artery occlusion combined with systemic hypotension for 10 min. Cerebral perfusion-fixation was performed 7 days after ischemia, subsequent to which the brains were sectioned coronally and stained with celestine blue/acid fuchsin. In the neocortex and the hippocampal CA4 region, the lidocaine group showed less ischemic neuronal injuries than the control group. However, in the hippocampal CA1/CA3 regions and the caudoputamen, neuronal injuries in the lidocaine group were not significantly different from those in the control group. We conclude that the pre-ischemic subarachnoid administration of lidocaine reduces the delayed neuronal damage in neocortex and hippocampal CA4 region in the rat with forebrain ischemia.