Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Mechanism for Cardiac Arrhythmia discovered

18.09.2008
It has long been thought that virus infections can cause cardiac arrhythmia.

But why has not been understood. Ulrike Lisewski, Dr. Yu Shi, Michael Radke and Professor Michael Gotthardt of the Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch, Germany, have now discovered the molecular mechanism.

The researchers demonstrated that the receptor which the virus uses to infect heart cells is normally necessary for regular heart beat in mice. Likewise, when the receptor is absent or non-functioning, arrhythmia occurs. They assume that both the virus infection and the autoimmune disease can block the receptor which, in turn, disrupts the heart's normal rhythm. The study has now been published online in the Journal of Experimental Medicine (10.1084/jem.20510iti3).

The heart consists of two ventricles and two atria. In order to beat correctly and to pump blood through the body, specialized heart fibres generate electric signals that control the heart beat. Cardiac arrhythmia occurs when these signals are not correctly generated or forwarded. There, a receptor, which scientists call CAR, plays an important role.

CAR stands for Coxsackievirus-Adenovirus-Receptor. It is embedded in specific cell-cell-contacts (tight junctions) of the specialized heart fibres. CAR was discovered as the critical protein responsible for virus entry during infection with Coxsackie and Adenoviruses. Its role in the adult heart was previously unknown.

To investigate CAR's task in a healthy organism, the MDC-scientists switched off the CAR-gene in adult mice. As a result, the rodents could no longer produce the receptors and developed cardiac arrhythmia. "That is an interesting observation because these special cell-cell-contacts, the tight junctions, have not been connected to arrhythmia so far", Professor Gotthardt says.

A detailed analysis of the animals showed that the transfer of electric signals from the atria to the ventricles does not work properly. "When CAR is missing, the signal can not be passed on and the heart does not beat properly," Dr. Shi says.

Professor Gotthardt now wants to investigate whether CAR is blocked in patients with arrhythmia. "However, it does not always have to be connected to a virus infection," he says. "The body's own antibodies directed against CAR could cause the disease as well."

The tight junction protein CAR regulates cardiac conduction and cell-cell communication

Ulrike Lisewski1, Yu Shi1, Uta Wrackmeyer1, Robert Fischer2, Chen Chen1, Alexander Schirdewan2, Rene Jüttner3, Fritz Rathjen3, Wolfgang Poller4, Michael H. Radke1 and Michael Gotthardt1,5

1Neuromuscular and Cardiovascular Cell Biology, Max-Delbrück-Center for Molecular Medicine (MDC),
13122 Berlin-Buch, Germany, 2 HELIOS Kliniken GmbH, Franz-Volhard Klinik, Charité, Humboldt-
University, 13125 Berlin, Germany, 3Department of Molecular Pathology, University Hospital Tübingen,
D-72073 Tuebingen, Germany, 4 Department of Cardiology, Campus Benjamin Franklin, D-12200 Berlin,
Germany, 5Department of Veterinary and Comparative Anatomy, Pharmacology, and Physiology,

Washington State University, Pullman, Washington, 99164 USA.

Barbara Bachtler
Press and Public Affairs
Max Delbrück Center for Molecular Medicine (MDC) Berlin-Buch
Robert-Rössle-Str. 10¸13125 Berlin, Germany
Phone: +49 (0) 30 94 06 - 38 96
Fax: +49 (0) 30 94 06 - 38 33
e-mail: presse@mdc-berlin.de

Barbara Bachtler | idw
Further information:
http://www.mdc-berlin.de/en/news

More articles from Life Sciences:

nachricht Researchers find new mutation in the leptin gene
24.06.2019 | Texas Biomedical Research Institute

nachricht Straight to the heart
24.06.2019 | Max-Delbrück-Centrum für Molekulare Medizin in der Helmholtz-Gemeinschaft

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Fraunhofer IDMT demonstrates its method for acoustic quality inspection at »Sensor+Test 2019« in Nürnberg

From June 25th to 27th 2019, the Fraunhofer Institute for Digital Media Technology IDMT in Ilmenau (Germany) will be presenting a new solution for acoustic quality inspection allowing contact-free, non-destructive testing of manufactured parts and components. The method which has reached Technology Readiness Level 6 already, is currently being successfully tested in practical use together with a number of industrial partners.

Reducing machine downtime, manufacturing defects, and excessive scrap

Im Focus: Successfully Tested in Praxis: Bidirectional Sensor Technology Optimizes Laser Material Deposition

The quality of additively manufactured components depends not only on the manufacturing process, but also on the inline process control. The process control ensures a reliable coating process because it detects deviations from the target geometry immediately. At LASER World of PHOTONICS 2019, the Fraunhofer Institute for Laser Technology ILT will be demonstrating how well bi-directional sensor technology can already be used for Laser Material Deposition (LMD) in combination with commercial optics at booth A2.431.

Fraunhofer ILT has been developing optical sensor technology specifically for production measurement technology for around 10 years. In particular, its »bd-1«...

Im Focus: The hidden structure of the periodic system

The well-known representation of chemical elements is just one example of how objects can be arranged and classified

The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to...

Im Focus: MPSD team discovers light-induced ferroelectricity in strontium titanate

Light can be used not only to measure materials’ properties, but also to change them. Especially interesting are those cases in which the function of a material can be modified, such as its ability to conduct electricity or to store information in its magnetic state. A team led by Andrea Cavalleri from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg used terahertz frequency light pulses to transform a non-ferroelectric material into a ferroelectric one.

Ferroelectricity is a state in which the constituent lattice “looks” in one specific direction, forming a macroscopic electrical polarisation. The ability to...

Im Focus: Determining the Earth’s gravity field more accurately than ever before

Researchers at TU Graz calculate the most accurate gravity field determination of the Earth using 1.16 billion satellite measurements. This yields valuable knowledge for climate research.

The Earth’s gravity fluctuates from place to place. Geodesists use this phenomenon to observe geodynamic and climatological processes. Using...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

SEMANTiCS 2019 brings together industry leaders and data scientists in Karlsruhe

29.04.2019 | Event News

Revered mathematicians and computer scientists converge with 200 young researchers in Heidelberg!

17.04.2019 | Event News

 
Latest News

2nd International Conference on UV LED Technologies & Applications – ICULTA 2020 | Call for Abstracts

24.06.2019 | Event News

'Sneezing' plants contribute to disease proliferation

24.06.2019 | Agricultural and Forestry Science

Researchers find new mutation in the leptin gene

24.06.2019 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>