Evidence that adrenaline activates key oxidative enzymes in rat liver by increasing intramitochondrial [Ca2+]

FEBS Letters

McCormack, James G.¹ 

[1] Department of Biochemistry, University of Bristol Medical School, University Walk, Bristol BS8 1TD, England

关键词: Liver;    Adrenaline;    Mitochondrial metabolism;    Intramitochondrial [Ca2+];    Pyruvate dehydrogenase;    Oxoglutarate dehydrogenase;   

DOI  :  10.1016/0014-5793(85)81082-6

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The effects of intramitochondrial Ca²⁺ on the activities of the Ca²⁺-sensitive intramitochondrial enzymes, (i) pyruvate dehydrogenase (PDH) phosphate phosphatase, and (ii) oxoglutarate dehydrogenase (OGDH), were investigated in intact rat liver mitochondria by measuring (i) the amount of active PDH (PDHa) and (ii) the rate of decarboxylation of α-[1-¹⁴C]oxoglutarate (at non-saturating [oxoglutarate]), at different concentrations of extramitochondrial Ca²⁺. In the presence of Na²⁺ and Mg²⁺, both PDH and OGDH could be activated by increases in extramitochondrial [Ca²⁺] within the expected physiological range (0.05–5 μM). When liver mitochondria were prepared from rats treated with adrenaline, and then incubated in Na-free media containing EGTA, both PDH and OGDH activities were found to be enhanced. Evidence is presented that the activation of these enzymes by adrenaline is brought about by a mechanism involving increases in intramitochondrial [Ca²⁺].

【 授权许可】

Unknown