Neurotoxicity of Glia Activated by Gram-Positive Bacterial Products Depends on Nitric Oxide Production

摘要: The present study examined the mechanism by which bacterial cell walls from two gram-positive meningeal pathogens, Streptococcus pneumoniae and group B streptococcus, induced neuronal injury in primary cultures of rat brain cells. Cell both organisms produced cellular to similar degrees pure astrocyte but not cultures. also nitric oxide production astrocytes or microglia. When neurons were cultured together with microglia, became toxic neurons. L-NAME, a synthase inhibitor, protected wall-induced toxicity mixed glia, as did dexamethasone. In contrast, an excitatory amino acid antagonist (MK801) had no effect. Low concentrations either pathogen added glutamate resulted synergistic neurotoxicity that was inhibited L-NAME. induction independent presence serum, whereas endotoxin exhibited these effects only serum. We conclude can cause inducing