Medical Research Council - London Institute of Medical Sciences

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12 November 2012


During the scariest bit of the film, you feel a familiar pounding in your chest. Most of the time, however, our heartbeat goes unnoticed. To keep an adult human going the heart has to beat 60-80 times a minute – that’s over 100,000 times a day. This constant activity relies on a carefully choreographed pattern of electrical signals, produced by the movement of calcium ions. Now, using zebrafish genetically engineered to produce a calcium-sensitive fluorescent protein, scientists can watch as signals are conducted through its tube-shaped heart. When viewed under a microscope, computer software maps the fluorescent signals (white) through the beating heart. The red lines show how the electrical signal moves from right to left, marking its position every 60 milliseconds. This new approach to studying the heart could give important insights into various cardiac diseases, driving the development of better treatments.

Written by Emma Stoye

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