Post-traumatic Stress Disorder (PTSD)
Conditions
Keywords
Post-traumatic stress disorder (PTSD), Trauma, Neuroimaging, Positron emission tomography (PET), [11C]OMAR, Endocannabinoid
Brief summary
The objective of the proposed translational study is to test a model, based upon basic science studies, exploring multisystem impairments in PTSD including endocannabinoid (eCB) and glucocorticoids in the modulation of fear memories by examining the cannabinoid type 1 (CB1) receptor in a PTSD fear circuit as well as glucocorticoid function. The investigators propose that impaired eCB signaling in PTSD resulting in the maladaptive neurobehavioral response to the stressor is associated with an upregulation of the CB1 receptors and insufficient glucocorticoid signaling.
Detailed description
The eCB - anandamide and 2-arachidonoylglycerol (2-AG) - and their attending cannabinoid (CB) receptors which are found in high densities in a fear circuitry involving the amygdala, hippocampus, the anterior cingulate cortex and prefrontal cortex serve important functions in the regulation of stress-coping behaviors. Besides eCB regulation there is strong evidence from ongoing research of the investigators group and others suggesting an important role for glucocorticoid signaling as an endpoint of the biochemical sequelae initiated by stressful or aversive stimuli. One of the long-term research goals of our lab is to understand such functions and determine their relevance to the pathogenesis of PTSD and to provide a more integrative view on neurobiological mechanisms that are involved in the regulation of the neuroadaptive response to stress. The objective of the proposed translational study is to test a model, based upon basic science studies, exploring multisystem impairments in PTSD including eCB and glucocorticoids in the modulation of fear memories by examining the CB1 receptor in a PTSD fear circuit as well as glucocorticoid function. The investigators propose that impaired eCB signaling in PTSD resulting in the maladaptive neurobehavioral response to the stressor is associated with an upregulation of the CB1 receptors and insufficient glucocorticoid signaling.
Interventions
Positron emission tomography (PET) imaging
Sponsors
Study design
Eligibility
Inclusion criteria
for Patients with PTSD: 1. age 18-55 years old 2. currently diagnosed with PTSD and symptomatic with a Clinician-Administered PTSD Scale (CAPS) score \> 50. Inclusion Criteria for healthy subjects: 1. age 18-55 years old 2. no personal or first-degree family history of any Axis I diagnosis.
Exclusion criteria
for Patients with PTSD: 1. any primary Axis I disorder other than PTSD (e.g. psychosis); 2. medical or neurological illnesses likely to affect physiology or anatomy, i.e. uncontrolled hypertension, cardiovascular disorders; 3. a history of drug (including benzodiazepines (BZD)) dependence (DSM IV criteria) within 1 year of the study and lasting longer than 2 years, except for alcohol dependence 4. current pregnancy (as documented by pregnancy testing at screening or on the day of PET imaging study) 5. current breast feeding 6. nicotine dependence 7. suicidal ideation or behavior 8. general MRI
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Volume of distribution (VT) of cerebral CB1 receptor expression in PTSD and controls within a fear circuit of brain regions that regulate stress-related behaviors using the CB1 radioligand carbon - 11 (11C) [11C]OMAR and PET. | Two months | To examine group differences in cerebral CB1 receptor expression in PTSD and controls within a fear circuit of cortical and subcortical brain regions that regulate stress-related behaviors using the CB1 radioligand \[11C\]OMAR and PET. Hypothesis: PTSD patients will show greater \[11C\]OMAR VT (i.e. CB1 binding) values than both control groups, trauma-exposed and non-trauma exposed control subjects who will not be different. |
Countries
United States