Researchers Vadim Bolshakov, PhD, director of the cellular neurobiology labratory at McClean Hospital in Massachusetts, and David Clapham, MD, PhD, professor of cardiovascular research at the Children's Hospital Boston, have identified a protein in the brain that acts as a trigger for innate fear responses. McClean hospital is the largest psychiatric affiliate of Harvard Medical School, where Bolshakov and Clapham also teach.
Absence of the protein, known as transient receptor potential channel 5 (TRPC5), was linked to a lowered fear response in mice. Mice without TRPC5 were more likely to explore strange environments and interact with strange mice, behaviors that would normally elicit the fear response. How does TRPC5 affect fear? TRPC5 is usually found in concentrated amounts in the amygdala, and facilitates the function of this brain structure that regulates fear. In addition, those lacking TRPC5 are not as sensitive to the neuropeptide cholecystokinin (CCK), which is commonly released during the experience of innate fear.
This study is the first time that TRPC5 has been explicitly linked to the fear response, and offers a potential target for new medications aimed at treating chronic problems with anxiety, such as social anxiety disorder (SAD).
Paper published in the May issue of Cell.
Photo © Microsoft