Kuznetsov 2004 Am J Physiol Heart Circ Physiol
|Kuznetsov AV, Schneeberger S, Seiler R, Brandacher G, Mark W, Steurer W, Saks V, Usson Y, Margreiter R, Gnaiger E (2004) Mitochondrial defects and heterogeneous cytochrome c release after cardiac cold ischemia and reperfusion. Am J Physiol Heart Circ Physiol 286:H1633–41.|
Abstract: Mitochondria play a critical role in myocardial cold ischemia-reperfusion (CIR) and induction of apoptosis. The nature and extent of mitochondrial defects and cytochrome c (Cyt c) release were determined by high-resolution respirometry in permeabilized myocardial fibers. CIR in a rat heart transplant model resulted in variable contractile performance, correlating with the decline of ADP-stimulated respiration. Respiration with succinate or N,N,N',N'-tetramethyl-p-phenylenediamine dihydrochloride (substrates for Complexes II and IV) was partially restored by added Cyt c, indicating Cyt c release. In contrast, NADH-linked respiration (glutamate&malate) was not stimulated by Cyt c, owing to a specific defect of Complex I. CIR but not cold ischemia alone resulted in the loss of NADH-linked respiratory capacity, uncoupling of oxidative phosphorylation and Cyt c release. Mitochondria depleted of Cyt c by controlled hypoosmotic shock provided a kinetic model of homogenous Cyt c depletion. Comparison to Cyt c control of respiration in CIR-injured myocardial fibers indicated heterogeneity of Cyt c release. The Complex I defect and uncoupling correlated with heterogeneous Cyt c release, the extent of which increased with loss of cardiac performance. These results demonstrate a complex pattern of multiple mitochondrial damage as determinants of CIR injury of the heart.
• Keywords: Heart preservation, Complex I injury, Permeabilized myocardial fibers
Labels: MiParea: Respiration, mt-Biogenesis;mt-density, mt-Medicine
Stress:Ischemia-reperfusion Organism: Rat Tissue;cell: Heart Preparation: Intact organ, Permeabilized tissue, SMP, Enzyme Enzyme: Marker enzyme Regulation: Coupling efficiency;uncoupling, Cyt c, Flux control, Threshold;excess capacity Coupling state: LEAK, OXPHOS Pathway: N, S, CIV, ROX HRR: Oxygraph-2k
- Referred to in Gnaiger_2012_MitoPathways, Chapter 1.