But when anxiety grows excessive -- as it does in an estimated 25 percent of U.S. residents sooner or later -- it can significantly reduce one's quality of life, and in the cases of some 20 million Americans at any given time, it reaches levels that may require treatment.
"We have effective compounds already for treating anxiety that are some of the most commonly prescribed medications worldwide," said Dr. Clyde W. Hodge, associate professor of psychiatry at the University of North Carolina at Chapel Hill School of Medicine. "Among these are benzodiazepines, such as Valium. The problem with them, however, is that they act as sedatives, which often prevent people from functioning normally. And people can become addicted to them." As a result, he said, a worldwide search is on for less disruptive alternatives. Working with colleagues at the University of California at San Francisco, Hodge now may have good news about that search.
"What we've done is to identify a potential new target in the brain for new, less problematic anxiety-reducing medications of the future," Hodge said. Combining genetic, drug and behavioral studies in mice, he and his colleagues have found that mice lacking a form of the enzyme protein kinase C (PKC-epsilon) are extremely sensitive to their brains' own calming neurosteroid compounds and show significantly less anxiety than normal mice with PKC-epsilon, he said. The scientists conclude that inhibitors of PKC therefore may be useful in treating anxiety.
A report on the findings appears in the October issue of the Journal of Clinical Investigation. Besides Hodge, who is lead author, contributors include Drs. Jacob Raber now of Oregon Health and Science University in Po
Contact: David Williamson
University of North Carolina at Chapel Hill