Nature of respiratory stimulation in hyperthyroidism: the redox behaviour of cytochrome c

FEBS Letters

Gennari, F¹  Azzone, G.F¹  Luvisetto, S¹  Schmehl, I¹  Canton, M¹ 

[1] CNR Unit for the Study of Biomembranes and Department of Biomedical Sciences, University of Padova, via Trieste 75, 35131-Padova, Italy

关键词: Hyperthyroidism;    Cytochrome c;    Cytochrome oxidase;    Mitochondrion;    Uncoupling;    Δψ;    transmembrane electrical potential;    J o rate of respiration;    BSA;    bovine serum albumin;    BSA-Hyper;    BSA-supplemented hyperthyroid mitochondria;    DNP;    2;    4-dinitrophenol;    FCCP;    carbonyl cyanide p-(trifluoromethoxy)-phenylhydrazone;    FCCP-Eu;    FCCP-supplemented euthyroid mitochondria;    Eu;    euthyroid mitochondria;    RLM;    rat liver mitochondria;    T3;    3;    3;    5-triiodo-l-thyronine;   

DOI  :  10.1016/0014-5793(95)01211-V

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Hyperthyroid mitochondria show an increased K _m and V _max in the high affinity phase of cytochrome oxidase kinetics. During inhibitor titrations, cytochrome c shows a different redox behaviour in hyperthyroid with respect to protonophore-treated euthyroid mitochondria. The observations are discussed in terms of a different regulation of electron input and output into the respiratory chain during slip and leak types of uncoupling. In hyperthyroid mitochondria during inhibitor titrations, the pattern of the relationship between uncoupler-induced extra-respiration and membrane potential is highly non-linear. The complex nature of the respiratory stimulation in hyperthyroid mitochondria is discussed.

【 授权许可】

Unknown