Therefore, to clarify the long-term effects of a single icv injection of Aβ25–35 oligomers (oAβ25–35) and to evaluate a potential impact of such short Aβ fragment in the progression of AD, we conducted a study to determine its behavioral, physiological, biochemical and morphological impacts in healthy adult male rats, 6 weeks after a single icv injection, including changes in APP processing, Aβ1–42 generation and Tau hyperphosphorylation. The gene discussed is MAPT; the disease is Alzheimer disease.