Archive for Sunday, December 10, 1995


December 10, 1995


Scientists at KU delved into mind-expanding research that may lead to therapies that help people recover from brain damage.

Kansas University researcher Steve Schroeder met Tom about 10 years ago in a state mental retardation hospital.

Tom had Lesch-Nyhan syndrome, an intensely disabling condition that affects one in 150,000 Americans.

People like Tom uncontrollably chew their lips and fingers. Often bedridden, their backs stiffen into a permanent arch. They show diminished mental powers and explosive behavior that leads to attacks on caregivers.

Typically, they die before turning 40.

"This was a guy in a supported chair with tremendous physical disabilities," Schroeder said. "As a young boy, he had been biting himself and had to have his teeth removed. He had severe scars on his face."

Schroeder, director of KU's Institute for Life Span Studies, and KU professor Richard Tessel think they're on the track of a new therapy that could help people like Tom.

Their study, which will be reported in the journal Brain Research, indicated that aggressive training of laboratory rats elevated levels of a natural brain chemical -- dopamine -- connected with voluntary movement, learning and emotion.

Lesch-Nyhan sufferers have very low levels of dopamine, a chemical messenger between brain cells.

Tessel, KU professor of pharmacology and toxicology, said this research on brain-damaged rats suggested for the first time that it might be possible to reverse what had been thought to be irreversible brain damage in Lesch-Nyhan sufferers.

"Our data suggest that engagement in learning tasks can actually be therapeutic," Tessel said. "Even if you lose it, but then use it, some of it will come back."

Schroeder said the research could one day have application to a broad range of brain disorders.

"In our view," Schroeder said, "this finding should have implications for any brain disorder that involves cognition, learning and memory."

In the KU study, Tessel and Schroeder worked with KU graduate student Christopher Stodgell to experimentally manipulate rats to have the same kind of brain damage found in children with Lesch-Nyhan.

The study involved four test groups: untrained healthy rats; untrained brain-damaged rats; minimally trained brain-damaged rats; and extensively trained brain-damaged rats.

The two brain-damaged groups of rats that received training were taught to push levers a certain number of times to receive food. After training was completed, all four groups were sacrificed and their brains analyzed.

Researchers were suprised to find dopamine levels were 300 percent higher in the brain-damaged rats with minimal training than in the untrained brain-damaged rats.

Dopamine levels in the extensively trained brain-damaged rats were 600 percent higher than in the untrained brain-damaged rats.

"The animals who didn't have to learn as much didn't recover as much," Tessel said.

In a related study, Tessel and Schroeder worked with Pippa Loupe, a former KU graduate student.

They discovered that intense engagement in a learning task increased the weight of rats' hippocampus -- a brain structure believed important to memory -- by 35 percent. This occurred in rats that had been experimentally induced to have a small brain size associated with profound mental retardation.

Schroeder said this study suggested that the intensity of the engagement in learning may be crucial to recovery.

"The main implication is: use it or lose it," he said. "And, maybe, use it more than usual."

Tessel said skeptics have questioned their conclusions.

"My response to that is that science involves repeatability. We have repeated this twice. Now it's up to others to see if they can obtain similar findings," he said.

Schroeder and Tessel plan to continue working on their training theory with more advanced studies on rats.

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