Tiny fish lighting the future of pacemaker technology

January 18, 2011 8:01:22 PM PST
Bay Area researchers are hoping to someday use light to control critical functions of the human body. And while human applications may be years away, the technology is already a reality -- as long as you are a fish.

A room stacked with fish tanks might not be the first place one would expect to discover the pacemaker of the future. But researchers at UCSF believe tiny zebra fish could help unlock new ways of treating the human heart.

Researcher Herwig Baier says his team was intrigued by their ability to shine light into the bodies of the translucent fish. So in a recent trial, they genetically altered specific cardiac cells that control heart rhythm -- making them sensitive to light. Then, using a source similar to these fiber optic lasers, they hit the heart with light.

"When he turned the light on, it was a broad laser light the heart stopped beating," Baier said.

He says when they turned the light off, the heart beat normally again.

While flipping the heart on and off proved the concept, what came next was far more subtle. The team found that by manipulating the light, they could actually adjust the fish's heart rate

"So when we thought of the idea of a pacemaker, the idea crossed our minds that this could be a clinical application down the road," Baier said.

It would open up the possibility for a pacemaker that could send precise flashes of therapeutic light through fiber optic connections.

If it seems farfetched, consider that labs at several Bay Area universities are already experimenting with light sources to control everything from neural pathways to brain function. The field has been dubbed optogeneitcs.

Still, Baier believes huge advances will still have to be made before light based therapies for the heart become reality.

"Application is really years down the road, if ever, we still have to get gene therapy to work in the human heart," Baier said.

But if it is ultimately successful, historians may someday trace the beginnings, to a fish that is able to show a lot of heart.

One major advantage of the technology is that it does not generate the electrical pulses of a traditional pacemaker, which can produce side effects.

Written and produced by Tim Didion