New research shows how heart cells communicate to regulate heart activity

New research from Western University (London, Canada) is leading to a better understanding of what happens during heart failure; knowledge that could lead to better therapeutics or a more accurate predictor of risk. The research led by Robarts Research Institute scientists Robert Gros, PhD, and Marco Prado, PhD, along with graduate student Ashbeel Roy found the heart is regulated not only by nervous systems but also by heart cells sending messages to each other through the release of the neurotransmitter acetylcholine (ACh). The research has been published online by The FASEB Journal.

As Gros explains, is regulated by two nervous systems: the sympathetic and the parasympathetic. The sympathetic acts like an accelerator, speeding up the heart and the parasympathetic acts like a brake, decreasing the heart rate. When these systems get dysregulated or out of whack, it can lead to .

"But the heart is not well innervated or in other words, there are very few nerves to control the heart. So we wanted to know how the signal from the nerve is communicated throughout the heart. A neuronal system is nerve-based but now we're talking about a non-neuronal system, which means it's not in any but found in the heart cells themselves," says Gros, an associate professor in the Departments of Physiology & Pharmacology and Medicine at Western's Schulich School of Medicine & Dentistry and a scientist in the Vascular Biology Research Group at Robarts. "We've shown how the nerve sends a signal and individual heart cells pick up that signal; they can transduce that signal by the release of ACh from one cell to the next. It's the propagation of this signal that regulates the heart. Now we need to look at how this system changes in heart failure."

In collaboration with Robarts' scientist Vania Prado, PhD, Gros tested the theory using mice which were engineered so that their exclusively, could not release ACh. Under non-stressful conditions the mutant mice had normal heart rates. But when they exercised, these mice had a far greater increase in their heart rate, and it took longer for them to return to their pre-exercise heart rate, as compared to control mice. The results suggest the heart cell derived ACh may boost parasympathetic signaling to counterbalance sympathetic activity.

This video is not supported by your browser at this time.

Gros calls the research a kick start, because if this non neuronal source of ACh is playing such an important role in the heart, it's probably important in other organs as well. The research was supported by the Heart and Stroke Foundation of Ontario, the Canadian Institutes of Health Research and the Canada Foundation for Innovation.

add to favorites email to friend print save as pdf

Related Stories

Understanding the role of IKACh in cardiac function

Jul 15, 2013

Researchers have uncovered a previously unknown role for the acetylcholine-activated inward-rectifying potassium current (IKACh) in cardiac pacemaker activity and heart rate regulation, according to a st ...

Recommended for you

Gene variant raises risk for aortic tear and rupture

22 hours ago

Researchers from Yale School of Medicine and Celera Diagnostics have confirmed the significance of a genetic variant that substantially increases the risk of a frequently fatal thoracic aortic dissection or full rupture. ...

Considerable variation in CT use in ischemic stroke

22 hours ago

(HealthDay)—For patients with ischemic stroke there is considerable variation in the rates of high-intensity computed tomography (CT) use, according to a study published online April 8 in Circulation: Ca ...

Beating the clock for ischemic stroke sufferers

Apr 17, 2014

A ground-breaking computer technology raises hope for people struck by ischemic stroke, which is a very common kind of stroke accounting for over 80 per cent of overall stroke cases. Developed by research experts at The Hong ...

Risk for nonelective thoracic aortic sx up for uninsured

Apr 16, 2014

(HealthDay)—Uninsured patients have an increased risk of nonelective thoracic aortic operations, and have increased risks of major morbidity or mortality, according to a study published online April 8 in ...

User comments