Increased microglial activation and (microglial/neuronal) NO production in Alzheimer disease (AD) cortex tissue. A: Statistically significant increase in CD40 protein (p< 0.001) in AD samples indicates microglial activation. B: The expression of inducible nitric oxide synthase (iNOS) is elevated in AD compared to control brain tissue (p< 0.05). Quantification of the immunoreactive bands was determined by densitometry of the films using MCID program; pixel values were normalized to ß-III tubulin values for each sample (n=7 for each group)