Slowing the racing heart

May 11, 2007

Scientists have discovered how we put the brakes on a racing heartbeat.

Researchers at the University of Illinois at Chicago explain in the May 11 issue of Circulation Research how an enzyme acts on the heart's pacemaker to slow the rapid beating of the heart's "fight-or-flight" reaction to adrenaline.

A single cell in the upper right chamber is responsible for setting the pace of the beating heart, triggering its neighbor cells to beat. In the human heart, one cell -- the pacemaker cell -- beats faster or slower to induce a rhythmic heartbeat that varies to increase or decrease the blood flow to the body as we eat, sleep or exercise.

"Disturbances of pacemaker control are common in heart diseases. When the heartbeat becomes non-rhythmic and chaotic, it can result in fatal arrhythmias and stroke," said R. John Solaro, UIC distinguished university professor and principal investigator of the study.

Current treatment of arrhythmia requires destruction of tissue surrounding a chaotic pacemaker, followed by insertion of a mechanical pacemaker that can regulate the heartbeat.

"Understanding the molecular regulation of the heart's pacemaker opens the possibility of less drastic treatment options, including drug interventions," said Solaro, who is also director of the center for cardiovascular research and head of physiology and biophysics at UIC.

Solaro worked with Yunbo Ke, UIC research assistant professor of physiology and biophysics and first author of the paper, and colleagues in England at Oxford and Manchester on characterizing and isolating the pacemaker cell.

The UIC researchers demonstrated that an enzyme called Pak 1, present in high concentrations in the heart, signals depression in the action of adrenaline and adrenaline-like chemicals on the pacemaker cell, playing an important role in slowing down the heart rate.

"The enzyme works through calcium and potassium channels that we know to be key players in the generation and regulation of the pacemaker activity," said Ke.

"Although adrenaline and other mechanisms that accelerate the heart rate have been well studied, mechanisms that might act as a brake are poorly understood," said Solaro.

"Identification of this previously unknown molecular mechanism for slowing the heartbeat may offer new avenues of diagnosis, drug design and treatment of many common heart diseases," said Solaro.

"Further, now that we know something of how this enzyme works in the pacemaker cell, we may discover it is involved in the regulation of other processes, particularly in the brain, where it is also highly expressed," added Ke.

Source: University of Illinois at Chicago

Explore further: From stem cells to a functional heart—the role of the Mesp1 gene

Related Stories

From stem cells to a functional heart—the role of the Mesp1 gene

January 26, 2018
Researchers at the Université libre de Bruxelles and University of Cambridge identified the role of key gene Mesp1 in the earliest step of cardiovascular lineage segregation. This discovery may help to better understand ...

Diet may help fight epilepsy when meds fail

December 5, 2017
(HealthDay)—For children with epilepsy who don't find relief from their seizures with medication, a tightly controlled nutrition plan might help, a pair of new studies suggests.

Controlling diabetes with your phone might be possible someday

November 21, 2017
Think about this. You have diabetes, are trying to control your insulin levels and instead of taking a pill or giving yourself an injection, you click an app on your phone that tells your pancreas to bring blood sugar levels ...

Ordinary heart cells become 'biological pacemakers' with injection of a single gene

December 16, 2012
Cedars-Sinai Heart Institute researchers have reprogrammed ordinary heart cells to become exact replicas of highly specialized pacemaker cells by injecting a single gene (Tbx18)–a major step forward in the decade-long search ...

Technique to stimulate heart cells may lead to light-controlled pacemakers

August 9, 2011
(Medical Xpress) -- A new technique that stimulates heart muscle cells with low-energy light raises the possibility of a future light-controlled pacemaker, researchers reported in Circulation: Arrhythmia & Electrophysiology, ...

Scientists produce functional heart pacemaker cells

December 14, 2016
Scientists from the McEwen Centre for Regenerative Medicine, University Health Network, have developed the first functional pacemaker cells from human stem cells, paving the way for alternate, biological pacemaker therapy.

Recommended for you

Study looks at how newly discovered gene helps grow blood vessels

February 19, 2018
A new study published today found that a newly discovered gene helps grow blood vessels when it senses inadequate blood flow to tissues.

Scientists produce human intestinal lining that re-creates living tissue inside organ-chip

February 16, 2018
Investigators have demonstrated how cells of a human intestinal lining created outside an individual's body mirror living tissue when placed inside microengineered Intestine-Chips, opening the door to personalized testing ...

Data wave hits health care

February 16, 2018
Technology used by Facebook, Google and Amazon to turn spoken language into text, recognize faces and target advertising could help doctors fight one of the deadliest infections in American hospitals.

Researcher explains how statistics, neuroscience improve anesthesiology

February 16, 2018
It's intuitive that anesthesia operates in the brain, but the standard protocol among anesthesiologists when monitoring and dosing patients during surgery is to rely on indirect signs of arousal like movement, and changes ...

Team reports progress in pursuit of sickle cell cure

February 16, 2018
Scientists have successfully used gene editing to repair 20 to 40 percent of stem and progenitor cells taken from the peripheral blood of patients with sickle cell disease, according to Rice University bioengineer Gang Bao.

Appetite-controlling molecule could prevent 'rebound' weight gain after dieting

February 15, 2018
Scientists have revealed how mice control their appetite when under stress such as cold temperatures and starvation, according to a new study by Monash University and St Vincent's Institute in Melbourne. The results shed ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.