Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists Show Protein Plays Critical Role in Heart Failure in Both the Heart and Adrenal Gland

16.11.2005


A protein that plays an important regulatory role in heart failure in the heart also exerts powerful effects on the adrenal gland, Jefferson Medical College researchers have found. The protein, GRK2, is a potential drug target for heart failure.



Walter Koch, Ph.D., director of the Center for Translational Medicine in the Department of Medicine at Jefferson Medical College of Thomas Jefferson University in Philadelphia, and his co-workers had showed previously that GRK2, or G-protein coupled receptor kinase 2, is increased in the heart in heart failure, and shuts off certain receptors called beta-adrenergic receptors, desensitizing them.

When the heart is failing, the body’s sympathetic nervous system, which kicks into gear in the so-called fight or flight response, goes to work, releasing catecholamines – hormones such as epinephrine and norepinephrine in an ill-conceived attempt to stimulate the heart.


Catecholamines are released from two sources – nerve terminals and from the adrenal gland, from which they enter the circulation. Dr. Koch and his co-workers wondered if GRK2 and alpha 2-adrenergic receptor function were affected in the adrenal gland as well. They subsequently looked at adrenal glands from mice in heart failure, and found that GRK2 was increased.

According to Dr. Koch, when neurons release catecholamines, a feedback system that works through alpha 2-adrenergic receptors “is the brake on the system.” They found that mice in heart failure had high levels of GRK2 in the chromaffin cells in the adrenal gland, which caused the downregulation and desensitization of alpha 2 adrenergic receptors.

“Basically, the brake is being shut off,” he says. “We found that catecholamine release was high in adrenal cells in heart failure, and GRK2 appears to be the mechanism.” The researchers report their results November 14, 2005 at the American Heart Association’s Scientific Sessions 2005 in Dallas.

When the scientists reduced GRK2 levels using an inhibitory peptide, ßARKct, catechomine release went down and the alpha 2-receptor function was restored, he notes. It appears that the increased GRK2 is a mechanism for catecholamine release, and contributes to the high catecholamines in heart failure. “The findings show that not only is GRK2 a target in the heart for heart failure, but also in the adrenal gland,” he says.

Next, Dr. Koch’s group is going to use gene therapy in the adrenal gland to decrease GRK2 activity and try to find out whether or not targeting the protein only in the adrenal gland will affect heart function simply by lowering catecholamines.

Steve Benowitz | EurekAlert!
Further information:
http://www.jefferson.edu

More articles from Life Sciences:

nachricht What the world's tiniest 'monster truck' reveals
23.08.2017 | American Chemical Society

nachricht Treating arthritis with algae
23.08.2017 | Empa - Eidgenössische Materialprüfungs- und Forschungsanstalt

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

What the world's tiniest 'monster truck' reveals

23.08.2017 | Life Sciences

Treating arthritis with algae

23.08.2017 | Life Sciences

Witnessing turbulent motion in the atmosphere of a distant star

23.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>