[Effect of thyroxine and 2,4-dinitrophenol on cardiac energetics].
The administrations of 1-thyrohine (20 mg/kg) for two sucessive daysin the rats or 10(-3) M 2,4-dinitrophenol (2,4-DNP) in vitro reduced the mechanical of the heart in working isolated preparations of the rat heart. Oxygen consumption of inactive heart did not react to thyroxine and significantly increased after 2,4-DNP administration. The reduction of the heart efficiency due to thyroxine is, probably, associated with a decreased efficiency of mechanochemical conjugation in the myocardium muscular fibers.
D000818:Animals; D004140:Dinitrophenols / Q000494:pharmacology*; D004734:Energy Metabolism / Q000187:drug effects*; D006321:Heart / Q000187:drug effects*; D008297:Male; D008931:Mitochondria, Muscle / Q000378:metabolism; D009200:Myocardial Contraction / Q000187:drug effects; D009206:Myocardium / Q000378:metabolism; D010085:Oxidative Phosphorylation / Q000187:drug effects; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D013974:Thyroxine / Q000494:pharmacology*
D004140:Dinitrophenols; D013974:Thyroxine
Deĭstvie tiroksina i 2,4-dinitrofenola na énergetiku serdtsa