Relationship between Nitric Oxide Synthase and Neuronal Damage at the Subacute Stage of Focal Cerebral Ischemia

Objective To study the expression of three isoforms of nitric oxide synthase(NOS) and it's relation with neuronal damage at the subacute stage of focal cerebral ischemia in rat. Methods In a model of middle cerebral artery occlusion(MCAO) through monofilament nylon suture. Three kinds of NOS polyclone antibody\|SP immunochemisty technique were used to detected the expression of neuronal NOS(nNOS), inducible NOS(iNOS) and endothelial NOS(eNOS) after 24 h focal cerebral ischemia. \{Results\} 24 h after permanent focal cerebral ischemia, plenty of iNOS immunoreactivite glial cell were seen in the core and the periphery of the ischemic lesion, but the expression of nNOS and eNOS were downregulated in the infarct region. Conclusion The upregulated expression of iNOS in glial cells at the subacute stage of focal cerebral ischemia may be related to delayed neuronal cell death. It suggests that the use of selective iNOS inhibitors could be beneficial to reduce the neuronal ischemic damage.\;