Protocol | Published:

Comprehensive multilevel in vivo and in vitro analysis of heart rate fluctuations in mice by ECG telemetry and electrophysiology

Nature Protocols volume 11, pages 6186 (2016) | Download Citation

Abstract

The normal heartbeat slightly fluctuates around a mean value; this phenomenon is called physiological heart rate variability (HRV). It is well known that altered HRV is a risk factor for sudden cardiac death. The availability of genetic mouse models makes it possible to experimentally dissect the mechanism of pathological changes in HRV and its relation to sudden cardiac death. Here we provide a protocol that allows for a comprehensive multilevel analysis of heart rate (HR) fluctuations. The protocol comprises a set of techniques that include in vivo telemetry and in vitro electrophysiology of intact sinoatrial network preparations or isolated single sinoatrial node (SAN) cells. In vitro preparations can be completed within a few hours, with data acquisition within 1 d. In vivo telemetric ECG requires 1 h for surgery and several weeks for data acquisition and analysis. This protocol is of interest to researchers investigating cardiovascular physiology and the pathophysiology of sudden cardiac death.

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Acknowledgements

We thank K. Hennis for technical assistance with the Langendorff perfusion. The work of D.H.P. was supported by the Research Council of Lithuania (grant no. MIP-13037). This work was supported, in part, by funding from the German Research Foundation (DFG grant nos. BI 484/5-1, WA 2597/3-1 and SFB TRR 152 TP12) to M.B. and C.W.-S..

Author information

Affiliations

  1. Center for Integrated Protein Science (CIPS-M) and Center for Drug Research, Department of Pharmacy, Ludwig-Maximilians-Universität München, and DZHK (German Center for Cardiovascular Research), partner site Munich Heart Alliance, Munich, Germany.

    • Stefanie Fenske
    • , Rasmus Pröbstle
    • , Franziska Auer
    • , Sami Hassan
    • , Vanessa Marks
    • , Martin Biel
    •  & Christian Wahl-Schott
  2. Institute of Anatomy, Faculty of Medicine, Lithuanian University of Health Sciences, Institute of Anatomy, Kaunas, Lithuania.

    • Danius H Pauza

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Contributions

S.F. carried out the experiments and data analysis that formed the basis of the protocol, wrote the manuscript and composed all figures. R.P. provided images of isolated SAN cells, as well as images and videos of the anatomic localization of the SAN and isolation of the SAN, and wrote the manuscript. F.A. wrote the MATLAB script and performed data analysis. S.H. performed data analysis. V.M. and M.B. wrote the manuscript. D.H.P. developed the technique for inflation of the heart with gelatin and provided images of the anatomic localization of the SAN. C.W.-S. wrote the manuscript and designed the protocol.

Competing interests

The authors declare no competing financial interests.

Integrated supplementary information

Supplementary information

PDF files

  1. 1.

    Supplementary Text and Figures

    Supplementary Figures 1–3, Supplementary Tables 1 and 2, Supplementary Methods 1–3

Zip files

  1. 1.

    Supplementary Data 1

    Zip file containing 4 MATLAB scripts.

Excel files

  1. 1.

    Supplementary Data 2

    Raw data files for the tachograms shown in Figure 15g, Figure 16f and Figure 17f. These data files were used for the data analysis shown in Figure 15h-l, Figure 16g-k and Figure 17g-k.

Videos

  1. 1.

    Anatomy and localization of the SAN 1.

    Panoramic view across the supraventricular part of a gelatine inflated heart from the inferior vena cava over the SAN area to the right atrium.

  2. 2.

    Anatomy and localization of the SAN 2.

    View of an untreated heart before removal of the surrounding tissue. Fine forceps show the location of the SAN area.

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DOI

https://doi.org/10.1038/nprot.2015.139

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