Figure 1.

NO regulates NFκB activity as determined by electrophoretic mobility shift assays. (A) Cultured glia were incubated with l-NMMA (500 μM), and NFκB-binding activity was measured at 0, 2, 4, 8, 16, and 24 h after treatment. l-NMMA begins to enhance NFκB activity at 4 h, and at 24 h there is a dramatic increase in NFκB-binding activity. Excess l-Arg (5 mM) completely reversed l-NMMA-induced NFκB activation. (B) LPS (60 ng/ml) strongly enhances NFκB activity in glial cultures. LPS enhances NFκB activation at 2 h and continues up to 24 h after treatment with LPS. NOR-3 (100 μM) potently inhibits NFκB activation at all time points. Representative blots are shown for experiments that were performed at least three independent times with similar results.