Main Menu
Contact: Leigh Flynn
News Bureau
Northwestern State University
Natchitoches, LA 71497
(318) 357-6466
11/17/98
FOR IMMEDIATE RELEASE
NATCHITOCHES - A faculty member from the Louisiana Scholars' College at Northwestern State University is continuing research into the brain's control of feeding behavior. He presented a portion of that research during an international conference in Hungary.
Dr. Curt Phifer, associate professor of biology, presented the results of a collaborative study completed with Drs. Hans Berthoud and Alison Willing of the Pennington Biomedical Research Center in Baton Rouge. Phifer discussed that study at the International Confrence on the Physiology of Food and Fluid Intake, which meets every five years and served as a venue for basic and applied research on feeding behavior. This year's meeting was held at the Medical Schol in Pecs, Hungary -- the oldest medical school in Hungary and one of the oldest schools in Europe.
Phifer and the other researchers looked at the differences in brain activity caused by two types of stimuli that inhibit feeding. The ultimate goal of their research is to help people who have difficulty controlling their own eating.
"We have known for some time that eating behavior in humans and other animals has a variety of controls," Phifer said. "Some of these include the taste of food, a full or empty stomach, nutrients in the intestine, blood nutrient levels and perhaps even the concentration of nutrient compounds in our cells. But we know very little about how these different factors affect the brain and actually change behavior.
"In our study, we wanted to compare effects on the brain from two of the more powerful inhibitors of eating, that is, a full stomach versus nutrients in the intestine," Phifer said.
He said the team used rats in which they had surgically implanted stomach tubes for filling of the stomach and smaller intestingal tubes for infusing specific types of nutrients. Brain activity in specific regions was determined by using specific antibodies to label individual nerve cells that were stimulated by signals from the full stomach or the intestine.
"The two groups of rats, thos that had filled stomachs and those that had nutrients in their intestine, showed interesting similarities and differences in terms of the brain areas that were activated," Phifer said.
He said a specific area of the brainstem, the nucleus tractus solitarius, which has long been known to play a role in feeding-behavior control, was stimulated in both groups.
"But stomach distension and nutrients in the intestine produced strikingly different patterns of activity in this region of the brain."
He and his colleagues saw important implications from the similarities and differences in brain effects caused by the two different types of signals. In an effort to further understand the effects on the brain, Phifer is extending his analysis to new brain regions.
"We have already looked at the next step in the neural pathway, and we have found that different types of nutrients in the intestine produce different types of brain activity. We certainly have a long way to go, but piece by piece, we are gaining a better understanding of the ways the brain controls eating and other behaviors."