Decreased nuclear factor-kappa B DNA binding activity following permanent focal cerebral ischaemia in the rat

Many factors implicated in the pathogenesis of cerebral ischaemia such as g lutamate, tumour necrosis factor and interleukin-1 have a Iso been shown to activate nuclear factor-kappa B (NF-kappa B). In the present study we have investigated NF-kappa B activity at various times following permanent foca l cerebral ischaemia in rats using immunohistochemistry, western blotting a nd electrophoretic mobility sh ift assay (EMSA). Three hours following midd le cerebral artery occlusion nuclear translocation of NF-kappa B was detect ed using immunohistochemical and western blotting techniques. This was refl ected in a trend towards increased NF-kappa B binding activity (EMSA) in th e ischaemic cortex compared to histologically normal tissue. In contrast ho wever, from 6 to 48 h post-occlusion nuclear translocation and NF-kappa B b inding activity was decreased in the ischaemic cortex. Decreased NF-kappa B binding activity detected in degenerating neurones, suggests that decrease d NF-kappa B activity may exacerbate ischaemia induced neuronal cell death. (C) 2000 Elsevier Science Ireland Ltd. Ail rights reserved.