Abstract
Ischemia–reperfusion (I/R) injury causes dynamic changes in electrophysiological properties that promote the incidence of post-ischemic arrhythmias. High-resolution optical action potential mapping allows for a quantitative assessment of the electrophysiological substrate at a cellular resolution within the intact heart, which is critical for elucidation of arrhythmia mechanisms. We and others have found that pharmacological inhibition of the translocator protein (TSPO) is highly effective against postischemic arrhythmias. A major hurdle that has limited the translation of this approach to patients is the fact that available TSPO ligands have several confounding effects, including a potent negative ionotropic property. To circumvent such limitations we developed an in vivo cardiac specific TSPO gene silencing approach as an alternative. Here, we provide the methodological details of our optical action potential mapping studies that were designed to probe the effects of TSPO silencing in hearts from spontaneously hypertensive rats (SHR) that are prone to I/R injury.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Roth GA, Huffman MD, Moran AE et al (2015) Global and regional patterns in cardiovascular mortality from 1990 to 2013. Circulation 132(17):1667–1678. https://doi.org/10.1161/CIRCULATIONAHA.114.008720
Hausenloy DJ, Yellon DM (2013) Myocardial ischemia-reperfusion injury: a neglected therapeutic target. J Clin Invest 123(1):92–100. https://doi.org/10.1172/JCI62874
Akar FG, Aon MA, Tomaselli GF et al (2005) The mitochondrial origin of postischemic arrhythmias. J Clin Invest 115(12):3527–3535. https://doi.org/10.1172/JCI25371
Aon MA, Cortassa S, Akar FG et al (2006) Mitochondrial criticality: a new concept at the turning point of life or death. Biochim Biophys Acta 1762(2):232–240. S0925-4439(05)00105-5
Jin H, Nass RD, Joudrey PJ et al (2010) Altered spatiotemporal dynamics of the mitochondrial membrane potential in the hypertrophied heart. Biophys J 98(10):2063–2071. https://doi.org/10.1016/j.bpj.2010.01.045
Nederlof R, Xie C, Eerbeek O et al (2013) Pathophysiological consequences of TAT-HKII peptide administration are independent of impaired vascular function and ensuing ischemia. Circ Res 112(2):e8–e13. https://doi.org/10.1161/CIRCRESAHA.112.274308
Xie C, Hu J, Motloch LJ et al (2015) The classically cardioprotective agent diazoxide elicits arrhythmias in type 2 diabetes mellitus. J Am Coll Cardiol 66(10):1144–1156. https://doi.org/10.1016/j.jacc.2015.06.1329
Brown DA, Aon MA, Akar FG et al (2008) Effects of 4′-chlorodiazepam on cellular excitation-contraction coupling and ischaemia-reperfusion injury in rabbit heart. Cardiovasc Res 79(1):141–149. https://doi.org/10.1093/cvr/cvn053
Seccia TM, Atlante A, Vulpis V et al (1998) Mitochondrial energy metabolism in the left ventricular tissue of spontaneously hypertensive rats: abnormalities in both adeninenucleotide and phosphate translocators and enzyme adenylate-kinase and creatine-phosphokinase activities. Clin Exp Hypertens 20(3):345–358
Molgaard S, Faricelli B, Salomonsson M et al (2016) Increased myocardial vulnerability to ischemia-reperfusion injury in the presence of left ventricular hypertrophy. J Hypertens 34(3):513–523.; discussion 523. https://doi.org/10.1097/HJH.0000000000000826
Tang Y, Mi C, Liu J et al (2014) Compromised mitochondrial remodeling in compensatory hypertrophied myocardium of spontaneously hypertensive rat. Cardiovasc Pathol 23(2):101–106. https://doi.org/10.1016/j.carpath.2013.11.002
Jullig M, Hickey AJ, Chai CC et al (2008) Is the failing heart out of fuel or a worn engine running rich? A study of mitochondria in old spontaneously hypertensive rats. Proteomics 8(12):2556–2572. https://doi.org/10.1002/pmic.200700977
Meng C, Jin X, Xia L et al (2009) Alterations of mitochondrial enzymes contribute to cardiac hypertrophy before hypertension development in spontaneously hypertensive rats. J Proteome Res 8(5):2463–2475. https://doi.org/10.1021/pr801059u
Ito H, Torii M, Suzuki T (1995) Decreased superoxide dismutase activity and increased superoxide anion production in cardiac hypertrophy of spontaneously hypertensive rats. Clin Exp Hypertens 17(5):803–816
Power AS, Pham T, Loiselle DS et al (2016) Impaired ADP channeling to mitochondria and elevated reactive oxygen species in hypertensive hearts. Am J Physiol Heart Circ Physiol 310(11):H1649–H1657. https://doi.org/10.1152/ajpheart.00050.2016
Lyon AR, Joudrey PJ, Jin D et al (2010) Optical imaging of mitochondrial function uncovers actively propagating waves of mitochondrial membrane potential collapse across intact heart. J Mol Cell Cardiol 49(4):565–575. https://doi.org/10.1016/j.yjmcc.2010.07.002
Vanhoutte G, Verhoye M, Raman E et al (2002) In-vivo non-invasive study of the thermoregulatory function of the blood vessels in the rat tail using magnetic resonance angiography. NMR Biomed 15(4):263–269. https://doi.org/10.1002/nbm.768
Acknowledgments
This work was supported by grants from the National Institutes of Health (R01 HL091923 and R21AG054211) and the American Heart Association (13GRNT17000046) to FGA.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2018 Springer Science+Business Media, LLC, part of Springer Nature
About this protocol
Cite this protocol
Ilkan, Z., Strauss, B., Campana, C., Akar, F.G. (2018). Optical Action Potential Mapping in Acute Models of Ischemia–Reperfusion Injury: Probing the Arrhythmogenic Role of the Mitochondrial Translocator Protein. In: Ishikawa, K. (eds) Experimental Models of Cardiovascular Diseases. Methods in Molecular Biology, vol 1816. Humana Press, New York, NY. https://doi.org/10.1007/978-1-4939-8597-5_10
Download citation
DOI: https://doi.org/10.1007/978-1-4939-8597-5_10
Published:
Publisher Name: Humana Press, New York, NY
Print ISBN: 978-1-4939-8596-8
Online ISBN: 978-1-4939-8597-5
eBook Packages: Springer Protocols