Skip to Main content Skip to Navigation
Journal articles

Macrocompartmentation of total creatine in cardiomyocytes revisited.

Abstract : Distribution of total creatine (free creatine + phosphocreatine) between two subcellular macrocompartments--mitochondrial matrix space and cytoplasm--in heart and skeletal muscle cells was reinvestigated by using a permeabilized cell technique. Isolated cardiomyocytes were treated with saponin (50 microg/ml for 30 min or 600 microg/ml for 1 min) to open the outer cellular membrane and release the metabolites from cytoplasm (cytoplasmic fraction, CF). All mitochondrial population in permeabilized cells remained intact: the outer membrane was impermeable for exogenous cytochrome c, the acceptor control index of respiration exceeded 10, the mitochondrial creatine kinase reaction was fully coupled to the adenine nucleotide translocator. Metabolites were released from mitochondrial fraction (MF) by 2-5% Triton X100. Total cellular pool of free creatine + phosphocreatine (69.6 +/- 2.1 nmoles per mg of protein) was found exclusively in CF and was practically absent in MF. When fibers were prepared from perfused rat hearts, cellular distribution of creatine was not dependent on functional state of the heart and only slightly modified by ischemia. It is concluded that there is no stable pool of creatine or phosphocreatine in the mitochondrial matrix in the intact muscle cells, and the total creatine pool is localized in only one macrocompartment--cytoplasm.
Document type :
Journal articles
Complete list of metadatas
Contributor : Sarah Hamant <>
Submitted on : Wednesday, June 3, 2009 - 12:21:50 PM
Last modification on : Friday, November 6, 2020 - 3:46:54 AM


  • HAL Id : inserm-00391059, version 1
  • PUBMED : 11451375




Laure Menin, Christiane Keriel, Jose Olivares, Urmo Braun, Enn Seppet, et al.. Macrocompartmentation of total creatine in cardiomyocytes revisited.. Molecular and Cellular Biochemistry, Springer Verlag, 2001, 220 (1-2), pp.149-59. ⟨inserm-00391059⟩



Record views