Astrocyte activators such as β-amyloid, γ-interferon, and gangliosides can activate NF-κB and increase gene expression of iNOS, and so increase astrocyte NO production.33, 34 It has been reported that PAR activation by proteases, like thrombin and trypsin, on the microglial cells, astrocytes, and C6 glioma cells activates NF-κB and increases NO production. The gene discussed is NOS2; the disease is central nervous system cancer.