NEW YORK, Sep 03 (Reuters Health) -- A small protein produced deep in the brain plays an important role in reactions to stress, according to an international team of researchers.
The finding may lead to new drugs and therapies for stress-related disorders.
Based on their earlier discovery of the protein, called orphanin FQ/nociceptin (OFQ/N), University of California, Irvine scientists and colleagues in Switzerland and Germany found that mice who lacked the gene required to produce OFQ/N displayed "increased anxiety-like behavior when exposed to a novel and threatening environment."
In their report, published this week in the Proceedings of the National Academy of Sciences, the researchers report that analysis of brain tissues from these stressed mice revealed concentrations of OFQ/N in several areas, including the hypothalamus and amygdala. These areas are essential players in modulating stress reactions.
In an interview with Reuters Health, Dr. Rainer Reinscheid of the University of California, Irvine discussed the significance of the group's findings. "The observation of impaired stress adaption in (mice that lack the ability to produce OFQ/N) are -- to our knowledge -- the first example of a (neurobiological) system acting in the fine-tuning of a brain response," he explained.
Asked how the findings might impact on the care of human patients, Reinscheid commented, "The identification of the specific function of a molecule in the brain is the first step to modulate its function by synthetic drugs." He adds that if a similar function can be demonstrated in humans, "the next logical step would be development of a drug that mimics the function of OFQ/N for the treatment of patients with anxiety disorders or anxiety-based depression... mental illnesses that affect a huge number of people."
Though "a number of pharmaceutical companies are actively working (in this area), it will probably take another 6 - 8 years until a drug could reach the market, " according to Reinscheid. He anticipates, however, that "proof of... function of OFQ/N in humans will hopefully be presented much sooner, within the next one or two years."
"I consider the chance that OFQ/N has a similar function in humans very high (since) the protein is 1000% identical between rat, mouse, and human and it is made in the same brain regions in all three species," Reinscheid explained.
Reinscheid and his colleagues are planning "to study the function of OFQ/N in other brain processes... (such as) drug addiction and withdrawal," he told Reuters Health.
