Hagfish (IMAGE) University of Guelph Caption University of Guelph researchers deprived hagfish hearts of oxygen and then fed the organs saline containing either glucose, glycerol or no fuel source. The researchers found feeding the hearts glycerol enhanced the hearts' contraction even more so then glucose, which is typically the fuel muscles prefer. These findings could have implications for preventing tissue damage to the human heart when oxygen delivery is impaired, such as during a heart attack or transplant. Credit University of Guelph 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.