Narrator: This is Science Today. Right now, the electrical system of your heart is sending signals every second to millions of cells to contract and when that contraction happens together, the heart works as a pump. Robin Shaw, an assistant professor of medicine at the University of California, San Francisco, studies the ion channels that carry these signals.
Shaw: There are ion channels that exist not only for each individual cell, but between each cell. These ion channels are known as gap junctions. I think of it as a passageway, a highly-regulated passageway.
Narrator: Basically, these junctions are the bridges over which signals flow. Shaw's research has revealed that these bridges disappear in a sequential manner every hour and new ones replace them. But why?
Shaw: It's a fascinating question and it speaks to the dynamic nature of the individual cells in the heart and how they probably have to respond to stress. What I study is how these ion channels are formed, how they get where they need to go and how this process is affected by a blocked artery.
Narrator: For Science Today, I'm Larissa Branin.