Mimicking the cardiac cycle in intact cardiomyocytes using diastolic and systolic force clamps; measuring power output

Cardiovasc Res. 2016 Jul 1;111(1):66-73. doi: 10.1093/cvr/cvw072. Epub 2016 Apr 1.

Abstract

Aims: A single isolated cardiomyocyte is the smallest functional unit of the heart. Yet, all single isolated cardiomyocyte experiments have been limited by the lack of proper methods that could reproduce a physiological cardiac cycle. We aimed to investigate the contractile properties of a single cardiomyocyte that correctly mimic the cardiac cycle.

Methods and results: By adjusting the parameters of the feedback loop, using a suitably engineered feedback system and recording the developed force and the length of a single rat cardiomyocyte during contraction and relaxation, we were able to construct force-length (FL) relations analogous to the pressure-volume (PV) relations at the whole heart level. From the cardiac loop graphs, we obtained, for the first time, the power generated by one single cardiomyocyte.

Conclusion: Here, we introduce a new approach that by combining mechanics, electronics, and a new type optical force transducer can measure the FL relationship of a single isolated cardiomyocyte undergoing a mechanical loop that mimics the PV cycle of a beating heart.

Keywords: Cardiomyocyte function; Force–length relation; Microtechnology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Animals
  • Diastole*
  • Equipment Design
  • Feedback, Physiological
  • Fiber Optic Technology
  • Interferometry
  • Mechanotransduction, Cellular*
  • Miniaturization
  • Myocytes, Cardiac / physiology*
  • Rats
  • Signal Processing, Computer-Assisted
  • Systole*
  • Time Factors
  • Transducers, Pressure*