Heart Light Illustration (IMAGE) Johns Hopkins University Caption In this illustration, the "optrode" at left delivers blue light to the heart via a fiber-optic tip. In the enlargement at right, a heart cell (large red oval) contains an implanted light-sensitive "opsin" protein (blue oval) that works alongside the heart's own proteins (yellow ovals). This teamwork allows the cell to convert light energy into an electric kick that triggers a healthy heartbeat. Credit Patrick M. Boyle Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.