Aftin-4, an amyloid forty-two inducer, activates γ-secretase, promoting the generation of amyloid-β-1-42 (Aβ1-42) from amyloid-β protein precursor. Aftin-4(Aftin4) increased Aβ-1-42, but not Aβ-1-40 in mouse hipppocampus, accompanied by learning deficits and mitochondrial ultrastructural changes similar to those found in the brains of patients with AD. Aftin-4(Aftin4) can thus be used to induce a rapid, acute Alzheimer’s disease-like toxicity in the rodent brain.