Fig. 4.

Microglia isolated from iNOS-deficient mice failed to produce NO and induce toxicity to preOLs. Microglia were isolated from iNOS-deficient and wild-type mice and cocultured with preOLs. The cocultures were treated with and without 5 μg/ml LPS for 24 h. (A and B) Expression of iNOS and generation of NO were demonstrated by Western blot (A) and the Greiss reaction (B), respectively. (C) Surviving preOLs were counted based on immunostaining for O4. ***, P < 0.0001 wild-type cultures with LPS treatment compared with wild type without LPS treatment; ns, not significant. Results are representative of three independent experiments.