Finding the Beat

To keep our hearts beating in time the autonomic nervous system carries pulses of electrical activity deep into their muscular walls, causing repeating patterns of contractions. Usually hidden behind layers of fatty molecules, the nerves in this mouse heart are revealed in bright colours under a high-powered microscope after a chemical wash to clear the fats away. Computer algorithms help to spot the ‘circuits’ of nerves, colour-coding them by diameter (left, blue thinnest, red thickest) or by their orientation with the heart (right). These patterns reveal fresh details about how heart rhythm in maintained, but also provide a comparison for future studies – using similar techniques to examine how these patterns are disrupted by cardiovascular diseases and conditions such as myocardial infarction.

Written by John Ankers

John Ankers

Writer

A former researcher in systems biology, John is now an online biology tutor and professional coach supporting the wellbeing of scientists and NHS professionals. He's writing, too, of course.

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• Image from work by Pradeep S. Rajendran and colleagues
• Cardiac Arrhythmia Center and Neurocardiology Research Program of Excellence, David Geffen School of Medicine, University of California - Los Angeles (UCLA), Los Angeles, CA, USA
• Image originally published under a Creative Commons Licence (BY 4.0)
• Published in Nature Communications, April 2019