Researchers have created an animal model that shows how chronic stress affects behavior, physiology and reproduction.
Yerkes scientists developed the model to better understand the neurohormonal causes of such stress and how the body reacts to the insult. Investigators believe the approach will aid the development of more effective treatment options for humans.
The study is available in the current online edition of Molecular Psychiatry.
Via the animal model, the researchers found corticotropin releasing factor (CRF) is a key neurohormone involved in stress response.
In response to stress, CRF levels rise; CRF levels decrease when the stressor no longer is present.
Chronic stress, however, increases the length and volume of expression of CRF in areas of the brain associated with fear and emotion, including the amygdala.
Such chronic stress changes the body’s response, and the resulting increased expression of CRF is thought to be the cause of such health-related stress problems including anxiety, depression and infertility.
To study the importance of CRF, the research team used a viral vector to increase the production of CRF in the amygdala of female rats.
“In our study, rats that continuously were exposed to CRF from this area of the brain experienced anxious and depressive behavior, decreased libido and disrupted ovarian cycles suggesting that persistent release of CRF such as occurs in chronic stress clearly affects multiple body systems,” says Wilson.
Dr. Wilson and his research team next will attempt to learn more about the negative effects of increased CRF by examining actual molecular and cellular changes in specific brain areas targeted by the neurohormone.
Knowing how CRF affects the brain positions the researchers to develop better treatment options.