NGF and Alzheimer disease: In AD, pro-NGF is increased in frontal and occipital cortex (Crutcher et al.1993; Fahnestock et al.2001; Hellweg et al.1998; Peng et al.2004) and in hippocampus (Hock et al.2000a; Narisawa-Saito et al.1996; Scott et al.1995), while a loss is observed in the basal forebrain (Mufson et al.1995; Scott et al.1995).