Featured Research

from universities, journals, and other organizations

Daily Rhythms In Blood Vessels May Explain Morning Peak In Heart Attacks

Date:
November 11, 2008
Source:
Emory University
Summary:
Daily rhythms in the activity of cells that line blood vessels may help explain why heart attacks and strokes occur most often in early morning hours, researchers have found.

It's not just the stress of going to work. Daily rhythms in the activity of cells that line blood vessels may help explain why heart attacks and strokes occur most often in early morning hours, researchers from Emory University School of Medicine have found.

Related Articles


Endothelial cells serve as the interface between the blood and the arteries, controlling arterial tone and helping to prevent clots that lead to strokes and heart attacks, says Ibhar Al Mheid, MD, a postdoctoral cardiology researcher at Emory.

"One of the important ways the lining of our blood vessels is maintained is by progenitor cells that come from the bone marrow," Al Mheid says. "These are essentially stem cells that help replace endothelial cells at sites of injury and build new vessels at sites deprived of adequate blood supply. The aim of our research was to look at the circadian pattern of both endothelial function -- the ability of blood vessels to relax -- and the abundance of the progenitor cells."

Working with Arshed Quyyumi, MD, professor of medicine and director of the Emory Cardiovascular Research Group, and colleagues, Al Mheid examined a dozen healthy middle-aged subjects every four hours for 24 hours. They drew blood while the subjects were asleep at 4 a.m. Blood vessel relaxation is assessed by cuff occlusion, a standard technique in measuring blood pressure – and was not measured at 4 a.m.

The researchers measured the ability of subjects' blood vessels to relax, the abundance of endothelial progenitor cells (EPCs) and their ability to grow in culture. Both the ability of blood vessels to relax and EPCs' ability to grow peaked (roughly 40 percent more than the middle of the day) at midnight, while cell numbers peaked at 8 p.m.

"The lining of our vessels appears to function better at night than in the day. Endothelial function is particularly depressed in the early morning hours," Al Mheid says.

He hypothesizes that an innate circadian timer in the brain, which other scientists have shown to be influenced by light and dark and daily activities, drives the cyclical variations in EPCs and endothelial function.

Ibhar Al Mheid is scheduled to present his results in a poster session on Nov. 10 at the American Heart Association Scientific Sessions in New Orleans.


Story Source:

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


Cite This Page:

Emory University. "Daily Rhythms In Blood Vessels May Explain Morning Peak In Heart Attacks." ScienceDaily. ScienceDaily, 11 November 2008. <www.sciencedaily.com/releases/2008/11/081110112051.htm>.
Emory University. (2008, November 11). Daily Rhythms In Blood Vessels May Explain Morning Peak In Heart Attacks. ScienceDaily. Retrieved March 6, 2015 from www.sciencedaily.com/releases/2008/11/081110112051.htm
Emory University. "Daily Rhythms In Blood Vessels May Explain Morning Peak In Heart Attacks." ScienceDaily. www.sciencedaily.com/releases/2008/11/081110112051.htm (accessed March 6, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Friday, March 6, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Bupa Eyes India Healthcare Opportunities

Bupa Eyes India Healthcare Opportunities

Reuters - Business Video Online (Mar. 5, 2015) Bupa is hoping to expand in India&apos;s fast-growing health insurance market, once a rule change on foreign investment is implemented. The British private healthcare group&apos;s CEO tells Grace Pascoe why it&apos;s so keen on the new opportunity. Video provided by Reuters
Powered by NewsLook.com
Liberia Releases Last Ebola Patient, But Threat Remains

Liberia Releases Last Ebola Patient, But Threat Remains

Newsy (Mar. 5, 2015) Liberia&apos;s last Ebola patient has been released, and the country hasn&apos;t recorded a new case in a week. However, fears of another outbreak still exist. Video provided by Newsy
Powered by NewsLook.com
Doctor in Your Pocket Is Getting Smarter

Doctor in Your Pocket Is Getting Smarter

Reuters - Business Video Online (Mar. 5, 2015) Mobile apps are turning smartphones into a personal doctors, with users able to measure heart rate, blood pressure and even blood sugar. But will it change our behaviour? Ivor Bennett reports from the Mobile World Congress in Barcelona. Video provided by Reuters
Powered by NewsLook.com
AbbVie Inks $21B Deal To Buy Cancer Drugmaker Pharmacyclics

AbbVie Inks $21B Deal To Buy Cancer Drugmaker Pharmacyclics

Newsy (Mar. 5, 2015) AbbVie announced Wednesday it will buy cancer drugmaker Pharmacyclics in a $21 billion deal. 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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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