In situ Raman study of redox state changes of mitochondrial cytochromes in a perfused rat heart

PLoS One. 2013 Aug 29;8(8):e70488. doi: 10.1371/journal.pone.0070488. eCollection 2013.

Abstract

We developed a Raman spectroscopy-based approach for simultaneous study of redox changes in c-and b-type cytochromes and for a semiquantitative estimation of the amount of oxygenated myoglobin in a perfused rat heart. Excitation at 532 nm was used to obtain Raman scattering of the myocardial surface of the isolated heart at normal and hypoxic conditions. Raman spectra of the heart under normal pO2 demonstrate unique peaks attributable to reduced c-and b-type cytochromes and oxymyoglobin (oMb). The cytochrome peaks decreased in intensity upon FCCP treatment, as predicted from uncoupling mitochondrial respiration. Conversely, transient hypoxia causes the reversible increase in the intensity of peaks assigned to cytochromes c and c1, reflecting electron stacking proximal to cytochrome oxidase due to the lack of terminal electron acceptor O2. Intensities of peaks assigned to oxy- and deoxyhemoglobin were used for the semiquantitative estimation of oMb deoxygenation that was found to be of approximately 50[Formula: see text] under hypoxia conditions.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cytochromes / chemistry
  • Cytochromes / metabolism*
  • Hypoxia / metabolism
  • In Vitro Techniques
  • Male
  • Mitochondria, Heart / metabolism*
  • Myocardial Ischemia / metabolism
  • Myocardium / metabolism*
  • Myocytes, Cardiac / metabolism
  • Myoglobin / chemistry
  • Myoglobin / metabolism
  • Oxidation-Reduction
  • Oxygen Consumption
  • Rats
  • Spectrum Analysis, Raman*

Substances

  • Cytochromes
  • Myoglobin

Grant support

Support for this work came from The Danish Council for Independent Research | Natural Sciences (to NAB and OVS). MT, BF, and JHV were supported by The Danish National Research Foundation for Heart Arrhythmia, the A. and E. Danielsens Foundation and E. and H. Fraenkels Memorial Foundation. NAB acknowledges financial support from Federal Target Program Research and development in priority areas of scientific-technological complex of Russia for 2007{2013, goverment contract 14.512.11.0035 and Russian Foundation for Basic Research, project 12-04-31133 (mol-a)). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.