Featured Research

from universities, journals, and other organizations

Oxygen-Carrying Myoglobin Not Necessary For Survival

Date:
October 31, 1998
Source:
University Of Texas Southwestern Medical Center At Dallas
Summary:
Myoglobin, the protein long thought to be the sole carrier of oxygen to heart and certain skeletal muscle, is not necessary for survival, UT Southwestern Medical Center at Dallas scientists reported in the October 29 issue of the journal Nature.

DALLAS -- Myoglobin, the protein long thought to be the solecarrier of oxygen to heart and certain skeletal muscle, is notnecessary for survival, UT Southwestern Medical Center at Dallasscientists reported in the October 29 issue of the journal Nature.

Because of this discovery, investigators will be able to delvefurther into causes, prevention and cures for heart failure. Theresearchers made their breakthrough by developing a strain ofmice lacking the gene to produce myoglobin, which transportsoxygen from capillaries to mitochondria in heart and endurancemuscle cells. Mitochondria are the structures within cells thattransform oxygen and other molecules into energy for allcellular functions.

"Myoglobin is found in the heart and the slow-twitch, orendurance, skeletal muscles in a number of species. So becauseof its prevalence and the energy required for contraction of theheart, we predicted that mice could not live without thisprotein," said Dr. Dan Garry, assistant professor of internalmedicine and first author of the report. "We were surprised thatnot only did they survive without it, they were born, developed,reproduced, nurtured and exercised normally."

The mice were exercised on treadmills along with littermatesthat had myoglobin. All the animals were exposed to conditionssimulating different altitudes at which the body would normallyexperience some lack of oxygen. Neither group showed anydifferences in their behavior or their ability to handle thedifferent conditions.

The only alteration researchers found in the rodents lackingmyoglobin was that the heart and endurance muscles werenonpigmented or almost white rather than a rich pink becausemost of the red color actually comes from the myoglobin. "Ourresearch suggests that the system transferring the oxygennecessary to fuel the contraction of heart and slow-twitchmuscles is much more complicated than the long-held paradigm,"Garry said.

Now, the researchers will look for other genes that areexpressed at a higher level in the genetically altered miceduring times when they are exposed to conditions where theirhearts and endurance muscles need more oxygen. In studying thesegenes, the investigators may be able to discover the system thatenables the heart and skeletal muscles to get the energy theyneed to continue functioning.

"We still believe that myoglobin is important, but somethingelse is also important; there are some cellular adaptations thatwe have not yet defined," Garry said. "By understanding andidentifying these adaptations, we will increase our knowledge ofwhat happens when people get chest pains. This will impact ourtreatment of patients who suffer from coronary-artery disease."

The other researchers on the study were: Dr. George Ordway,associate professor of physiology; Dr. Nina Radford, assistantprofessor of internal medicine; Dr. Eva Chin, postdoctoralfellow in internal medicine; Dr. Robert Grange, assistantinstructor of physiology; Dr. Rhonda Bassel-Duby, associateprofessor of internal medicine; Dr. R. Sanders Williams, chiefof cardiology, director of the Frank M. Ryburn Jr. Cardiaccenter and holder of the James T. Willerson, M.D., DistinguishedChair in Cardiovascular Diseases; and Dr. John Lorenz,Department of Molecular and Cellular Physiology, University ofCincinnati.

This work was supported by grants from the National Institutesof Health and the American Heart Association.


Story Source:

The above story is based on materials provided by University Of Texas Southwestern Medical Center At Dallas. Note: Materials may be edited for content and length.


Cite This Page:

University Of Texas Southwestern Medical Center At Dallas. "Oxygen-Carrying Myoglobin Not Necessary For Survival." ScienceDaily. ScienceDaily, 31 October 1998. <www.sciencedaily.com/releases/1998/10/981031174835.htm>.
University Of Texas Southwestern Medical Center At Dallas. (1998, October 31). Oxygen-Carrying Myoglobin Not Necessary For Survival. ScienceDaily. Retrieved August 30, 2014 from www.sciencedaily.com/releases/1998/10/981031174835.htm
University Of Texas Southwestern Medical Center At Dallas. "Oxygen-Carrying Myoglobin Not Necessary For Survival." ScienceDaily. www.sciencedaily.com/releases/1998/10/981031174835.htm (accessed August 30, 2014).

Share This




More Health & Medicine News

Saturday, August 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Liberia Continues Fight Against Ebola

Liberia Continues Fight Against Ebola

AFP (Aug. 30, 2014) Authorities in Liberia try to stem the spread of the Ebola epidemic by raising awareness and setting up sanitation units for people to wash their hands. Duration: 00:41 Video provided by AFP
Powered by NewsLook.com
California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

California Passes 'yes-Means-Yes' Campus Sexual Assault Bill

Reuters - US Online Video (Aug. 30, 2014) California lawmakers pass a bill requiring universities to adopt "affirmative consent" language in their definitions of consensual sex, part of a nationwide drive to curb sexual assault on campuses. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
3 Things To Know About The Ebola Outbreak's Progression

3 Things To Know About The Ebola Outbreak's Progression

Newsy (Aug. 29, 2014) Here are three things you need to know about the deadly Ebola outbreak's progression this week. 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:
from the past week

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