In thisregard, 192IgG-saporin (SAP), an immunotoxin directed against thelow affinity nerve growth factor receptor p75NTR, mainly expressedin BFCN, represents a powerful tool to specifically eliminate thosecells to mimic the cholinergic degeneration described in AD.15 The intraparenchymal infusion of 192IgG-saporinin the NBM of rats decreases ChAT and acetylcholinesterase (AChE)levels, reduces the density of the high-affinity Ch transporter, andmodifies the activity and cellular distribution of mAChR (see reviewfrom ref (16)). This evidence concerns the gene ACHE and Alzheimer disease.