Featured Research

from universities, journals, and other organizations

New Study Of The Genetic Causes Of Obesity Defies Traditional Thinking About The Role Of Adrenaline

Date:
May 1, 1997
Source:
University of Washington
Summary:
Scientists have long thought that the sympathetic (or autonomic) nervous system determines how the body uses energy from food. However, new studies reported in the May 1 edition of Nature appear to contradict traditional thinking.


Scientists have long thought that the sympathetic (or autonomic) nervous system determines how the body uses energy from food, deciding whether calories are burned up to keep the body warm, or stored in the form of fat.

However, new studies reported in the May 1 edition of Nature appear to contradict traditional thinking about the sympathetic nervous system's influence in people who never gain weight no matter how much they eat, versus those who seemingly put on pounds if a piece of cheesecake is merely passed under their nose.

To test whether deficiencies in the sympathetic nervous system may be a cause of obesity, University of Washington researchers Dr. Steven A. Thomas and Dr. Richard D. Palmiter produced mice that cannot make adrenaline (the hormone of the adrenal gland) or noradrenaline (the chemical messenger of the sympathetic nervous system). These two compounds are released in response to stress and regulate many body functions, including the ability to keep warm.

The mice that cannot make adrenaline and noradrenaline are unable to increase heat production, and they cannot defend themselves against heat loss; consequently, they lose heat rapidly in the cold.

"This was expected," said Palmiter, UW professor of biochemistry and an investigator of the Howard Hughes Medical Institute. "However, many scientists believed that under normal temperatures these mice would become obese because they wouldn't burn excess calories but instead would deposit them as fat."

"Instead, we found that at normal temperatures these mice do not become obese, despite the fact they eat more than normal," said Thomas, a senior fellow in biochemistry and first author of the UW study. "Our research suggests that obesity is not likely to involve defects in the sympathetic nervous system or in the production of adrenaline."

Noradrenaline normally produces heat by stimulating the production of protein called the uncoupling protein (UCP) in special brown fat cells. In the mice that lacked noradrenaline, this production did not take place.

A second study in the same issue of Nature corroborates the UW findings. Scientists at the Jackson Laboratory in Bar Harbor, Maine, produced mice that cannot make UCP. Like the UW mice, these mice do not become obese and they, too, are more sensitive to the cold.

A previous study by Drs. David E. Cummings and G. Stanley McKnight of the UW School of Medicine's Department of Pharmacology (published in Nature last year) indicated that chronic activation of the pathway leading to UCP production resulted in lean mice. Thus, there was ample reason to think that the opposite might be true if mice could not increase heat production after eating a meal.

"Both of the current studies, done independently and without each others' knowledge, produced consistent and unexpected results that are leading us to look in new directions for the genetic causes of obesity in humans," said Thomas.

The UW research was funded by grants from the Howard Hughes Medical Institute and the National Institutes of Health.


Story Source:

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


Cite This Page:

University of Washington. "New Study Of The Genetic Causes Of Obesity Defies Traditional Thinking About The Role Of Adrenaline." ScienceDaily. ScienceDaily, 1 May 1997. <www.sciencedaily.com/releases/1997/05/970501110427.htm>.
University of Washington. (1997, May 1). New Study Of The Genetic Causes Of Obesity Defies Traditional Thinking About The Role Of Adrenaline. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/1997/05/970501110427.htm
University of Washington. "New Study Of The Genetic Causes Of Obesity Defies Traditional Thinking About The Role Of Adrenaline." ScienceDaily. www.sciencedaily.com/releases/1997/05/970501110427.htm (accessed July 25, 2014).

Share This




More Health & Medicine News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

Beatings and Addiction: Pakistan Drug 'clinic' Tortures Patients

AFP (July 24, 2014) A so-called drugs rehab 'clinic' is closed down in Pakistan after police find scores of ‘patients’ chained up alleging serial abuse. Duration 03:05 Video provided by AFP
Powered by NewsLook.com
Too Few Teens Receiving HPV Vaccination, CDC Says

Too Few Teens Receiving HPV Vaccination, CDC Says

Newsy (July 24, 2014) The Centers for Disease Control and Prevention is blaming doctors for the low number of children being vaccinated for HPV. Video provided by Newsy
Powered by NewsLook.com
New Painkiller Designed To Discourage Abuse: Will It Work?

New Painkiller Designed To Discourage Abuse: Will It Work?

Newsy (July 24, 2014) The FDA approved Targiniq ER on Wednesday, a painkiller designed to keep users from abusing it. Like any new medication, however, it has doubters. Video provided by Newsy
Powered by NewsLook.com
Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Doctor At Forefront Of Fighting Ebola Outbreak Gets Ebola

Newsy (July 24, 2014) Sheik Umar Khan has treated many of the people infected in the Ebola outbreak, and now he's become one of them. 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