Measurement of the matrix free Ca2+ concentration in heart mitochondria by entrapped fura-2 and quin2.
A method was developed to monitor continuously the matrix free Ca2+ concentration ([Ca2+]m) of heart mitochondria by use of the fluorescent Ca2+ indicators, fura-2 and quin2. The acetoxymethyl esters of fura-2 and quin2 were accumulated in and hydrolysed by isolated mitochondria. An increase of the mitochondrial Ca content from 0.3 nmol/mg of protein to 6 nmol/mg corresponded to a rise of [Ca2+]m from 30 to 1000 nM. The results indicate that physiological fluctuations of the mitochondrial Ca content elicit changes of [Ca2+]m in that range which regulates the matrix dehydrogenases.
Department of Physiology, Semmelweis University Medical School, Budapest, Hungary.
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Lukács
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Kapus
D000634:Aminoquinolines; D000818:Animals; D001572:Benzofurans; D002118:Calcium / Q000378:metabolism*; D005456:Fluorescent Dyes; D016257:Fura-2 / Q000031:analogs & derivatives*; D008345:Manganese / Q000378:metabolism; D008929:Mitochondria, Heart / Q000378:metabolism*; D051381:Rats
D000634:Aminoquinolines; D001572:Benzofurans; D005456:Fluorescent Dyes; C049925:fura-2-am; D008345:Manganese; C035739:Quin2; D002118:Calcium; D016257:Fura-2