Brain Chemical Receptor Effects in Patients With Panic Disorder and Post-Traumatic Stress Disorder

Study Summary

The purpose of this study is to examine how certain brain chemicals work in patients with Panic Disorder (PD) and Post-Traumatic Stress Disorder (PTSD) with and without major depressive disorder (MDD). Brain chemicals that regulate emotion, anxiety, sleep, stress hormones, and other body functions bind to serotonin (5-HT1A) and benzodiazepine (BZD) receptors. Evidence suggests that 5-HT1A and BZD receptor function is abnormal in patients with PD, PTSD, and depression. This study will use positron emission tomography (PET) scans to examine BZD and 5-HT1A receptor binding potential in patients with PD and patients with PTSD with and without co-morbid MDD, as well as in healthy volunteers. This study will also determine the effects of the stress hormone cortisol on 5-HT1A and BZD receptors. The current emotional state and psychiatric, medical, and family history of potential participants will be evaluated during an initial telephone interview. After entering the study, participants will be asked questions about general mood, degree of nervousness, and behavior. A physical examination, an electrocardiogram (EKG), and tests of intelligence and cognition will be given. Urine, blood, and saliva samples will be taken. Women will be given pregnancy tests and tests to determine menstrual phase and time of ovulation. All volunteers will undergo magnetic resonance imaging (MRI) and PET scans of the brain. ...