Featured Research

from universities, journals, and other organizations

Sea squirt pacemaker gives new insight into evolution of the human heart

Date:
August 2, 2011
Source:
Wiley-Blackwell
Summary:
Molecular scientists have discovered that star ascidians, also known as sea squirts, have pacemaker cells similar to that of the human heart. The research may offer a new insight into the early evolution of the heart as star ascidians are one of the closest related invertebrates to mammals.

An international team of molecular scientists have discovered that star ascidians, also known as sea squirts, have pacemaker cells similar to that of the human heart. The research, published in the JEZ A: Ecological Genetics and Physiology, may offer a new insight into the early evolution of the heart as star ascidians are one of the closest related invertebrates to mammals.

The research team, led by Annette Hellbach from the Max Planck Institute of Biochemistry in Germany, expected to find clusters of HCN cells, the markers for pacemakers, at either end of the Botryllus schlosseri ascidian heart.

"The Botryllus schlosseri heart beats from one end to the other, stops for a short while and then starts to beat in the other direction," said Hellbach. "It would make sense to have two pacemakers on both ends from which the heartbeat is initiated, however, we found several HCN positive cells spread along the cardiac tube."

The team interpreted this finding as an evolutionary precursor to the elaborate cardiac conduction system found in mammals which are made up of clusters of pacemaker cells located in defined spots.

The team found that in comparison the cells in the B. schlosseri heart appeared to be randomly distributed along the heart; however, as with mammals the HCN cells played a vital role in generating the heartbeat.

The team also found that the cells responded to the blocking chemicals Cilobradine and Zatebradine by decreasing the heartbeat as is found to be the case for mice. This increases the likelihood that the cells operate through a similar molecular function.

"Our study reveals that the presence of HCN channels and their role in generating the heartbeat is shared between B. schlosseri and mammals," said Hellbach. "This makes colonial ascidians such as B. schlosseri insightful models for studies on the origins and evolution of vertebrate innovations, such as the pacemaker."


Story Source:

The above story is based on materials provided by Wiley-Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Annette Hellbach, Stefano Tiozzo, Jungho Ohn, Michael Liebling, Anthony W. De Tomaso. Characterization of HCN and cardiac function in a colonial ascidian. Journal of Experimental Zoology Part A: Ecological Genetics and Physiology, 2011; DOI: 10.1002/jez.695

Cite This Page:

Wiley-Blackwell. "Sea squirt pacemaker gives new insight into evolution of the human heart." ScienceDaily. ScienceDaily, 2 August 2011. <www.sciencedaily.com/releases/2011/08/110802090407.htm>.
Wiley-Blackwell. (2011, August 2). Sea squirt pacemaker gives new insight into evolution of the human heart. ScienceDaily. Retrieved August 23, 2014 from www.sciencedaily.com/releases/2011/08/110802090407.htm
Wiley-Blackwell. "Sea squirt pacemaker gives new insight into evolution of the human heart." ScienceDaily. www.sciencedaily.com/releases/2011/08/110802090407.htm (accessed August 23, 2014).

Share This




More Health & Medicine News

Saturday, August 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Drug Used To Treat 'Ebola's Cousin' Shows Promise

Newsy (Aug. 21, 2014) An experimental drug used to treat Marburg virus in rhesus monkeys could give new insight into a similar treatment for Ebola. Video provided by Newsy
Powered by NewsLook.com
Two US Ebola Patients Leave Hospital Free of the Disease

Two US Ebola Patients Leave Hospital Free of the Disease

AFP (Aug. 21, 2014) Two American missionaries who were sickened with Ebola while working in Liberia and were treated with an experimental drug are doing better and have left the hospital, doctors say on August 21, 2014. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com
Cadavers, a Teen, and a Medical School Dream

Cadavers, a Teen, and a Medical School Dream

AP (Aug. 21, 2014) Contains graphic content. He's only 17. But Johntrell Bowles has wanted to be a doctor from a young age, despite the odds against him. He was recently the youngest participant in a cadaver program at the Indiana University NW medical school. (Aug. 21) Video provided by AP
Powered by NewsLook.com
American Ebola Patients Released: What Cured Them?

American Ebola Patients Released: What Cured Them?

Newsy (Aug. 21, 2014) It's unclear whether the American Ebola patients' recoveries can be attributed to an experimental drug or early detection and good medical care. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins