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Zebrafish Heart Regeneration

More About Zebrafish Heart Regeneration

When the zebrafish heart is damaged, the wound site is rapidly sealed with a fibrin clot that stems bleeding within seconds. Following clot formation, the tissue that surrounds the heart muscle—the epicardium—gradually covers the fibrin clot via migration and cell division. Over the next few months, new cardiac muscle is produced and replaces the clot. Growth factors, like FGF1, produced by the new heart tissue, signals the cells of the epicardial layer to migrate into the heart and form new  blood vessels, to provide essential blood flow to the regenerating tissue. Over  time, the wounded zebrafish heart returns to nearly its original shape, size, and pumping ability.

Zebrafish Heart Regeneration Background

Although the human heart is virtually unable to regenerate new muscle when severely damaged, our vertebrate cousin the zebrafish can regenerate cardiac muscle to replace a massive section of damaged heart. Scientists want to understand why fish and humans should have such differing regenerative abilities, and especially hope that understanding how the fish heart regenerates will yield clues for improving therapy after human heart attacks. The zebrafish heart does have some structural differences with the human heart, having only two chambers instead of four, and having a more “spongy” composition that may facilitate clotting. If the role of important molecules like FGF1 can be determined in the zebrafish, the same molecules can then be studied in humans, and even explored as therapeutic agents.

From Lecture Four of the 2006 Holiday Lectures Series "Potent Biology: Stem Cells, Cloning, and Regeneration."

Zebrafish Heart Regeneration Teaching Tips

The animations in this section have a wide variety of classroom applications. Use the tips below to get started but look for more specific teaching tips in the near future. Please tell us how you are using the animations in your classroom by sending e-mail to biointeractive@hhmi.org.

  1. Use the animations to make abstract scientific ideas visible and concrete.
  2. Explain important scientific principles through the animations. For example, the biological clocks animations can be used to demonstrate the fundamentals of transcription and translation.
  3. Make sure that students learn the material by repeating sections of the animations as often as you think necessary to reinforce underlying scientific principles. You can start, restart, and play back sections of the animations.
  4. Urge students to use the animations in accordance with their own learning styles. Students who are more visually oriented can watch the animations first and read the text later, while others might prefer to read the explanations first and then view the graphics.
  5. Incorporate the animations into Web-based learning modules that you create to supplement your classroom curricula.
  6. Encourage students to incorporate the animations into their own Web-based projects.


The 2006 Holiday Lectures Series "Potent Biology: Stem Cells, Cloning, and Regeneration."

Zebrafish Heart Regeneration Credits

Director: Dennis Liu, Ph.D.

Scientific Direction: Ken Poss, Ph.D.

Scientific Content: Satoshi Amagai, Ph.D.

Animation: Blake Porch

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