title: Tight control of mitochondrial membrane potential by cytochrome c oxidase.
abstract: In the present work we have critically examined the use of the KCN-titration technique in the study of the control of the cellular respiration by cytochrome c oxidase (COX) in the presence of the mitochondrial membrane potential (Δψ(mito)) in HepG2 cells. We clearly show that the apparent high inhibition threshold of COX in the presence of maximal Δψ(mito) is due to the KCN-induced decrease of Δψ(mito) and not to a low control of COX on the mitochondrial respiration. The tight control exerted by COX on the Δψ(mito) provides further insights for understanding the pathogenetic mechanisms associated with mitochondrial defects in human neuromuscular degenerative disorders.
authors.affiliation: Department of Medical Biochemistry, Biology and Physics, University of Bari, Bari, Italy.
authors.forename: Consiglia
authors.initials: C
authors.lastname: Pacelli
authors.forename: Dominga
authors.initials: D
authors.lastname: Latorre
authors.forename: Tiziana
authors.initials: T
authors.lastname: Cocco
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Capuano
authors.forename: Christian
authors.initials: C
authors.lastname: Kukat
authors.forename: Peter
authors.initials: P
authors.lastname: Seibel
authors.forename: Gaetano
authors.initials: G
authors.lastname: Villani
mesh_terms: D002460:Cell Line; D003576:Electron Transport Complex IV / Q000502:physiology*; D006801:Humans; D008564:Membrane Potentials; D008928:Mitochondria / Q000502:physiology*; D010101:Oxygen Consumption
chemical_list: D003576:Electron Transport Complex IV