October 7 (HealthDay News) -- A fatty acid found in olive oil and other heart-healthy monounsaturated fats wards off hunger pangs, a new study suggests.

The findings might one day lead to the development of new drugs to limit, or even enhance, appetite, the researchers said.

Daniele Piomelli, a professor of pharmacology at the University of California, Irvine, and his colleagues infused the fat -- called oleic acid -- into the intestines of laboratory rodents and found that it was converted into a fat messenger called oleoylethanolamide (OEA).

"This OEA activates a receptor protein causing a specific type of satiety," Piomelli said. "This protein initiates a series of physiological events that lead to activation of nerves in the intestine."

The result: A message goes up to the brain and tells the body, in effect, that it's full. "This is different than compounds that make you eat less at a given meal," he said.

Piomelli and his team surgically infused the fat directly into the animals' intestines, then measured appetite. "The animals eat less," he said.

To further test the mechanism, they injected the fat into mice altered so they couldn't make OEA. "When you infuse the fat into these mice, they don't get the decreased hunger," he said.

The practical application? To someday make a drug that would slow OEA from being broken down in the body, thus extending the feeling of fullness. Likewise, OEA levels might be adjusted to help people who have decreased appetite, Piomelli said.

The findings are published in the October issue of Cell Metabolism.

Roger Clemens, director of regulatory science at the University of Southern California School of Pharmacy and a spokesman for the Institute of Food Technologists, said, "From a basic science perspective, it [the new study] is fascinating. It shows the importance of oleic acid."

And while the new research confirms previous work, Clemens said the practical applications remain in the future.

But he added this caution: Eating extra olive oil isn't a route to curbing hunger. While considered a heart-healthy fat, it contains calories that can add up quickly.

SOURCES: Daniele Piomelli, Ph.D., professor, pharmacology, University of California, Irvine, and director, Unit of Drug Discovery and Development, Italian Institute of Technology, Genoa, Italy; Roger Clements, Dr.P.H., spokesman, Institute of Food Technologists, and director, regulatory science, and professor, School of Pharmacology, University of Southern California, Los Angeles; October 2008 Cell Metabolism