Abstract
F1F0 ATP-synthase (complex V) deficiencies in Alzheimer's disease are reported. Tissue specimens from the hippocampus of brains from patients with Alzheimer's disease were screened by blue native electrophoresis for alterations of the proteins of oxidative phosphorylation. Ubiquinol:cytochrome-c reductase (complex III) and cytochrome-c oxidase (complex IV) were found to be present at almost normal concentrations, however, complex V was substantially reduced in most cases studied. The specific reduction of complex V and the absence of electrophoretically detectable degradation products do not exclude a secondary defect of complex V, but should stimulate the search for genetic defects related to protein subunits of complex V.