title: [Participation of SH-groups in regulating oxidative phosphorylation by malate and palmitate-uncoupled respiration in liver mitochondria].
abstract: The effect of malate on respiration in liver mitochondria has been studied during oxidation of succinate in the presence of rotenone both in state 3 and after palmitate addition. Malate was shown to stimulate the rate of mitochondrial respiration in the both respiratory states, its effect being increased in the presence of the NAD-dependent substrates of oxidation-glutamate and pyruvate or thiols (cysteine and thiourea) Preincubation of mitochondria for 5 min in the absence of respiratory substrates eliminated the stimulating effect of malate. However, this effect was manifested in the conditions when the NAD-dependent respiratory substrates or thiols were added after preincubation of mitochondria. p-Chloromercuribenzoate eliminated the stimulating effect of malate. Carboxyatractyloside and ATP inhibited mitochondrial respiration in the presence of palmitate. Malate did not influence the action of the first effector but eliminated that of the second effector. It is concluded that malate can regulate oxidative phosphorylation and palmitate-uncoupled respiration by affecting the adenine nucleotide transported. The SH-groups localized outside the mitochondria in the hydrophilic region play an important role in the realization of malate effects.
authors.forename: V N
authors.initials: VN
authors.lastname: Samartsev
authors.forename: I P
authors.initials: IP
authors.lastname: Zeldi
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001278:Atractyloside / Q000031:analogs & derivatives / Q000494:pharmacology; D004579:Electron Transport / Q000187:drug effects; D008293:Malates / Q000494:pharmacology*; D008930:Mitochondria, Liver / Q000187:drug effects* / Q000378:metabolism; D010085:Oxidative Phosphorylation / Q000187:drug effects*; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000494:pharmacology*; D051381:Rats; D013438:Sulfhydryl Compounds / Q000502:physiology*
chemical_list: D008293:Malates; D010169:Palmitic Acids; D013438:Sulfhydryl Compounds; D001278:Atractyloside; D019308:Palmitic Acid; C030298:malic acid; D000255:Adenosine Triphosphate; C003853:carboxyatractyloside
vernacular_title: Uchastie SH-grupp v reguliatsii malatom okislitel'nogo fosforilirovaniia i razobshchennogo pal'mitatom dykhaniia v mitokhondriiakh pecheni.