Cardiac Mitochondria

Cardiac Mitochondria KATP (SUR2A/ Kir6.2) Myocardial ischemia B MS-180448... 

Component Molecular Size Number of Peptide Subunits Prosthetic Croups Topology in Inner Membrane Abundance in Inner Membrane (nmol per mg Protein. Data for Cardiac Mitochondria) Proton Movements (the Stoichiometry is Discussed in Appendix 3)... 

Chen, Q., Camara, A.K., Stowe, D.F., Hoppel, C.L., and Lesnefsky, EJ. 2007. Modulation of electron transport protects cardiac mitochondria and decreases myocardial injury during ischemia and reperfusion. Am. J. Physiol. Cell Physiol. 292 C137-C147. 

Bollard ME, Murray AJ, Clarke K, Nicholson JK, Griffin JL. A smdy of metabolic compartmentation in the rat heart and cardiac mitochondria using high-resolution magic angle spinning IH NMR spectroscopy. FEBS Lett. 2003 553 73-78. 

C. P. Baines, C. X. Song, Y. T. Zheng, G. W. Wang, J. Zhang, O. L. Wang, Y. Guo, R. Bolli, E. M. Card-well and P. Ping, Protein kinase Cepsilon interacts with and inhibits the permeability transition pore in cardiac mitochondria, Circ Res 92, 873-880, (2003). 

P. Korge, H. M. Honda and J. N. Weiss, Protection of cardiac mitochondria by diazoxide and protein kinase C implications for ischemic preconditioning, Proc Natl Acad Sci USA 99, 3312-3317, (2002). 

Kanai AJ, Pearce LL, Clemens PR, Birder LA, Van Bibber MM, Choi SY, de Groat WC, Peterson J (2001) Identification of a neuronal nitric oxide synthase in isolated cardiac mitochondria using electrochemical detection. Proc Natl Acad Sci USA 98 14126-14131 Boveris A, Costa LE, Poderoso JJ, Cadenas E (2000) Regulation of mitochondrial respiration by oxygen and nitric oxide. Ann NY Acad Sci 899 121-135... 

Wisler JA, Dulaney MD, Pellicore LS et al. (1991). Transport of cyanide into guinea pig cardiac mitochondria. Toxicol Lett, 56, 275-281. 

Hence, were disposal of acetyl-CoA to keh enesis, the tricarhoxylic acid cycle or to acetyl-carnitine inhibited, feedback inhibition of P-oxidation would result and it has been suggested that this may control p-oxidation in cardiac mitochondria. However, although 3-ketoacyl-CoA esters are readily observed as intermediates of peroxisomal P-oxidation, we have never observed accumulation of 3-ketoacyl-CoA esters in mitochondrial incubations even at maximal P-oxidation flux and under conditions in which acetyl-CoA accumulates. Therefore, the accumulation of 3-ketoacyl-CoA esters may be strongly prevented and an excess of thiolase activity puBs P-oxidation as the... 

Figure 1 shows the complex ESR spectra from isolated cardiac mitochondria. They appear as a superposition of spectra from various paramagnetic components of the mitochondrial ETC. They are mainly iron-sulfur centers, denoted as Nl, N2, N3 - - 4 (located in complex I, NADFi-ubiquinone oxidoreductase), SI (complex II, succinate-ubiquinone oxidoreductase), and the Rieske iron-sulfur protein (complex III, ubihydroquinone-cytochrome C oxidoreductase). The positions of the components... 

The enlargement of the mitochondrial compartment in male Wistar rats placed on a copper-deficient diet at 10 days of age (Dallman and Goodman 1970) is related to the depletion of cytochromes and in activity of cytochrome oxidase (Dallman 1967). By feeding weanling mice the copper-chelating agent, cuprizone, Tandler and Hoppel (1972) considerably enhanced the number of cardiac mitochondria and the frequency of occurrence of partitioned mitochondria. 

The outer membrane of the mitochondrion contains a large number of pores, so that molecules with molecular weights less than 1,000 can pass from the cytoplasm into the intermembrane space without any specialized transport mechanisms. This means, for example, that NADH, ADP, and inorganic phosphate can reach the intermembrane space from the cytoplasm while NAD and ATP can reach the cytoplasm. The inner membrane is much less permeable, in part due to the presence of a specialized membrane lipid known as cardiolipin (meaning heart lipid—cardiac cells have a large number of mitochondria). The inner membrane of the mitochondrion is highly folded into cristae, so that it has an interleaved appearance in the electron microscope. 

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