Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Rats’ response to ’stop snacking’ signal diminished by high fat diet

03.08.2005


Rats fed a high fat diet were less sensitive to a hormonal ’stop eating’ signal than rats on a low fat diet when they were given access to a high calorie, high fat snack that the animals find yummy.



Dr. Mihai Covasa, assistant professor of nutritional sciences and a member of the Penn State Neuroscience Institute, led the study. He says, "When we gave the rats doses of a ’stop eating’ hormone, the rats on the low fat diet significantly suppressed their intake of the snack but not the rats on the high fat diet."

Covasa adds, "These results suggest that a long-term, high-fat diet may actually promote short-term overconsumption of highly palatable foods high in dietary fat by reducing sensitivity to at least one important feedback signal which would ordinarily limit eating."


The results are detailed in the current (August) issue of the Journal of Nutrition in a paper, Adaptation to a High-Fat Diet Leads to Hyperphagia and Diminished Sensitivity to Cholecystokinin in Rats. The authors are David M. Savastano, who recently earned his master’s degree under Covasa’s direction, and Covasa.

The ’stop eating’ hormone used in the study was cholecystokinin or CCK. CCK is released by cells in the small intestine when fat or protein is present. The hormone’s release activates nerves that connect the intestine with the brain where the decision to stop eating is made.

Previous studies with human subjects showed that those on a high fat diet have more CCK in their bloodstream but are less responsive to it. They typically report feeling increased hunger and declining fullness and eat more.

No human study of snacking and CCK has been reported. This study, with rats, is the first to link diminished sensitivity to CCK following exposure to a high fat diet and overconsumption of a high calorie, high fat snack.

In the current study, the rats were only given access to the high calorie, high fat snack for three hours a day. The rest of the time they received either low fat or high fat rat chow. The high and low fat chows were regulated so that they were equivalent in calories and both groups of rats gained weight at the same rate.

Even though the rats on the high fat diet ate, on average 40 percent more of the high calorie, high fat snack than the rats on the low fat diet, they didn’t gain extra weight. Rats, unlike humans, cut back on their usual chow when they snack.

Covasa says, "Rats are notorious in compensating for food to maintain a constant body weight. Although adaptation to the high fat diet led to overconsumption of the high calorie, high fat snack, there was no difference in weight gain between the two groups of rats during the 20 days of testing because the rats compensated by eating less of their maintenance diet."

Barbara Hale | EurekAlert!
Further information:
http://www.psu.edu

More articles from Studies and Analyses:

nachricht Obstructing the ‘inner eye’
07.07.2017 | Friedrich-Schiller-Universität Jena

nachricht Drone vs. truck deliveries: Which create less carbon pollution?
31.05.2017 | University of Washington

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

 
Latest News

NASA looks to solar eclipse to help understand Earth's energy system

21.07.2017 | Earth Sciences

Stanford researchers develop a new type of soft, growing robot

21.07.2017 | Power and Electrical Engineering

Vortex photons from electrons in circular motion

21.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>