NOS2 and Alzheimer disease: These findings are in agreement with an in vivo study carried out by Medeiros et al. (2007) in which the i.c.v. injection of Aβ1–40 induced iNOS protein expression in hippocampus and prefrontal cortex of mice that was paralleled by marked deficits of learning and memory, emphasizing the deleterious effects of aberrant expression of NOS isoforms in AD brain (Lüth et al., 2002).