Comparing Sex Differences in Animal Models of Post-Traumatic Stress Disorder
Michigan State University
Post-traumatic Stress Disorder (PTSD) is an abnormal, prolonged stress response to a traumatic event that affects an estimated 7% of the general population and up to 30% of post-war veterans in the US. Debilitating symptoms of PTSD can impede the lives of affected individuals for years or even decades. Women are more than twice as likely to develop PTSD than men, despite the fact that men are more likely to encounter traumatic events in their lifetime. The reason for the sex difference in PTSD is not understood as most of the PTSD literature has traditionally focused on male subjects, and a better understanding for the neurological mechanisms at work could help lay the groundwork for providing more specialized care to both men and women affected by the disorder. Previous research from our lab using rats has shown that there are a number of physiological and behavioral responses that differ between males and females who encounter a traumatic event, as found with our use of a well-validated animal model. My current study aims to test whether the sex differences seen with this model are generalizable to all forms of traumatic stress. To do so, I am using a different model of PTSD. I will measure male and female plasma levels of corticosterone, assess differences in HPA axis function after stress, and measure behavioral responses to acoustic startle. If the response in the second model displays a sex difference similar to the first model, I will conclude that the sexually dimorphic response to stress is not simply a peculiarity of a single model, and can be generalize to different forms of traumatic stress.