May 15 (HealthDay News) -- For almost 7 million Americans, fear and anxiety isn't something associated with heights, a job interview or getting lost in a strange city.
It's a chronic state of worry and tension that affects twice as many women as men and grinds away for no apparent reason, slowly eroding their quality of life.
But a new study published in the current issue of Cell has made a discovery that offers sufferers hope for a more relaxed life.
Researchers at McLean Hospital, an affiliate of Harvard Medical School, have identified a protein in the brain that triggers the fear response, and this could help with the development of new medications that block the protein or its pathways in brain cells.
"This is the first demonstration that this protein is implicated in fear-related behaviors," study author Vadim Bolshakov, director of the Cellular Neurobiology Laboratory at McLean, said in a news release from the hospital. "By identifying this trigger, we now have a greater likelihood of developing medications that will turn off the fear switch in the brain, and therefore significantly reduce anxiety."
The researchers looked at the neurons in the amygdala of mice that didn't have the TRPC5 protein, and found that they did not fire as well as those in the brains of normal mice.
These mice would not be fearful exploring new places or coming into contact with other mice -- situations that would typically cause anxiety.
David Clapham, a professor of neurobiology and pediatrics at Harvard Medical School, worked on the study and said that the protein is found throughout the brain, but highly concentrated in the amygdala, the part of the brain that is linked to emotions. Clapham also is the Aldo R. Castenada Professor of Cardiovascular Research at Children's Hospital Boston.
"These experiments provide genetic evidence that TRPC5 has an essential function in innate fear," the study's authors concluded.
"What we found with our work was that the mice who did not have the TRPC5 protein no longer showed fear-related behaviors when faced with situations that would typically cause them anxiety," Clapham said.
"At a practical level, it suggests some new potential molecular targets for treatments, some new kinds of treatments," Bolshakov added.
SOURCE: McLean Hospital, news release, May 15, 2009