Metabolic regulation of Ca2+ release in permeabilized mammalian skeletal muscle fibres. J Physiol 2003 Mar 01;547(Pt 2):453-62
Date
02/04/2003Pubmed ID
12562922Pubmed Central ID
PMC2342647DOI
10.1113/jphysiol.2002.036129Scopus ID
2-s2.0-0037337898 (requires institutional sign-in at Scopus site) 48 CitationsAbstract
In the present study, the link between cellular metabolism and Ca2+ signalling was investigated in permeabilized mammalian skeletal muscle. Spontaneous events of Ca2+ release from the sarcoplasmic reticulum were detected with fluo-3 and confocal scanning microscopy. Mitochondrial functions were monitored by measuring local changes in mitochondrial membrane potential (with the potential-sensitive dye tetramethylrhodamine ethyl ester) and in mitochondrial [Ca2+] (with the Ca2+ indicator mag-rhod-2). Digital fluorescence imaging microscopy was used to quantify changes in the mitochondrial autofluorescence of NAD(P)H. When fibres were immersed in a solution without mitochondrial substrates, Ca2+ release events were readily observed. The addition of L-glutamate or pyruvate reversibly decreased the frequency of Ca2+ release events and increased mitochondrial membrane potential and NAD(P)H production. Application of various mitochondrial inhibitors led to the loss of mitochondrial [Ca2+] and promoted spontaneous Ca2+ release from the sarcoplasmic reticulum. In many cases, the increase in the frequency of Ca2+ release events was not accompanied by a rise in global [Ca2+]i. Our results suggest that mitochondria exert a negative control over Ca2+ signalling in skeletal muscle by buffering Ca2+ near Ca2+ release channels.
Author List
Isaeva EV, Shirokova NAuthor
Olena Isaeva PhD Assistant Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsAntimycin A
Calcium
Carbonyl Cyanide p-Trifluoromethoxyphenylhydrazone
Drug Combinations
Female
Mitochondria, Muscle
Muscle Fibers, Skeletal
Muscle, Skeletal
Oligomycins
Permeability
Rats
Rats, Sprague-Dawley
Ruthenium Compounds
Signal Transduction
