Alzheimer's peptide kills cells in retina in vivo

Alzheimer's disease, the commonest form of dementia, is a progressive, age-dependent disorder characterized by the presence of large numbers of senile plaques and neurofibrillary tangles1. The neuritic plaques consist of an accumulation of amyloid-β peptide (Aβ); this substance, which derives from proteolysis of β-amyloid precursor protein (APP), seems to play a central role in the pathology of the disease. The toxicity of Aβ to neurons has already been demonstrated in vitro. Here we show that the peptide is also cytotoxic in vivo.