The Role of Norepinephrine in Emotional Processing
Investigating the Role of Norepinephrine in Emotional Processing Through Alpha-2 Adrenergic Receptor Modulation
2 other identifiers
observational
216
1 country
1
Brief Summary
This study will examine the role of a brain chemical called norepinephrine in thinking, decision-making, and emotional processing. After norepinephrine is released from a brain cell, it binds to another brain cell's receptor. Some of the receptors it binds to are called alpha-2 adrenergic receptors. This study will use medicines called yohimbine and guanfacine to look at the function of norepinephrine in the brain when it binds to the alpha-2 adrenergic receptors. Yohimbine increases norepinephrine's function and guanfacine decreases its function. Healthy volunteers between 20 and 50 years of age who do not have heart disease, high blood pressure, psychiatric illness, or other serious medical conditions and who are not allergic to lactose may be eligible for this study. Candidates are screened with a medical and psychiatric history, physical examination, neuropsychological testing, blood and urine tests and electrocardiogram. Women are screened with a urine pregnancy test. Participants are given a pill of yohimbine, guanfacine, or placebo and undergo the following tests and procedures:
- Blood pressure and heart rate measurements: Blood pressure and heart rate are measured before the medication is taken and several times after.
- Blood draws: Blood is drawn before the medicine is taken and 90 minutes after to measure levels of norepinephrine and the hormone cortisol.
- Neurocognitive testing: Participants do neurocognitive tasks on the computer for up to 90 minutes. The tasks involve looking at pictures or words on a screen and responding according to instructions given.
- Magnetic resonance imaging (MRI): Patients may undergo neurocognitive testing MRIs. This test uses a strong magnetic field and radio waves to show changes in brain activity. The subject lies on a table that slides into a narrow cylinder (the MRI scanner). Images of the brain are obtained while the subject performs the computer tasks.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for all trials
Started Apr 2005
Longer than P75 for all trials
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
Study Start
First participant enrolled
April 26, 2005
CompletedFirst Submitted
Initial submission to the registry
April 29, 2005
CompletedFirst Posted
Study publicly available on registry
May 2, 2005
CompletedPrimary Completion
Last participant's last visit for primary outcome
March 15, 2009
CompletedStudy Completion
Last participant's last visit for all outcomes
March 15, 2009
CompletedJuly 2, 2017
June 8, 2009
3.9 years
April 29, 2005
June 30, 2017
Conditions
Keywords
Eligibility Criteria
You may qualify if:
- Age: Participants will be males and females, 20-50 years of age.
- IQ: IQ, as measured by 4 subscales from the Wechsler Adult Intelligence Scale-Revised (WAIS-R), must be greater than 80.
- Medication status: No current use of any psychotropic medication or benzodiazepine.
You may not qualify if:
- Psychiatric History: Participants will be assessed using DSM-IV criteria via standardized psychiatric interviews conducted by trained examiners (SCID). All participants will be free of any current or past major affective disorder, psychotic disorder, substance dependence, anorexia, somatoform disorder, or anxiety disorders with the exception of specific phobias.
- Severe acute and chronic medical illnesses (e.g. cardiac disease, diabetes, epilepsy).
- CNS disease: Known history of brain abnormalities (e.g., neoplasms, subarachnoid cysts), cerebrovascular disease, infectious disease (e.g., abscess), other central nervous system disease, or history of head trauma which resulted in a persistent neurologic deficit or loss of consciousness greater than 3 minutes.
- Currently on regular medication that would interfere with study results. This includes alpha and beta adrenergic medications, other anti-hypertensive medications, glucocorticoid and mineralocorticoid medications, and medications causing sedation or stimulation. For example, current use of tylenol or ibuprofen is permitted, while current use of benadryl or methylphenidate is not. Use of oral contraceptive pills is permitted.
- Currently breast feeding or pregnant (as documented by pregnancy testing at screening or at days of the challenge studies).
- Metal or electronic objects: Metal plates, certain types of dental braces, cardiac pacemakers, etc., that are sensitive to electromagnetic fields contraindicate MRI scans.
- Claustrophobia: participants will be questioned about potential discomfort in being in an enclosed space, such as an MRI scanner.
- Body weight - to reduce the likelihood of significant orthostasis from guanfacine, participants must weigh 60kg or greater. Those weighing less than 60 kg will be excluded.
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (1)
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, 20892, United States
Related Publications (3)
Adolphs R. Neural systems for recognizing emotion. Curr Opin Neurobiol. 2002 Apr;12(2):169-77. doi: 10.1016/s0959-4388(02)00301-x.
PMID: 12015233BACKGROUNDArnsten AF. Adrenergic targets for the treatment of cognitive deficits in schizophrenia. Psychopharmacology (Berl). 2004 Jun;174(1):25-31. doi: 10.1007/s00213-003-1724-3. Epub 2003 Dec 19.
PMID: 15205875BACKGROUNDAron AR, Fletcher PC, Bullmore ET, Sahakian BJ, Robbins TW. Stop-signal inhibition disrupted by damage to right inferior frontal gyrus in humans. Nat Neurosci. 2003 Feb;6(2):115-6. doi: 10.1038/nn1003. No abstract available.
PMID: 12536210BACKGROUND
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Design
- Study Type
- observational
- Sponsor Type
- NIH
Study Record Dates
First Submitted
April 29, 2005
First Posted
May 2, 2005
Study Start
April 26, 2005
Primary Completion
March 15, 2009
Study Completion
March 15, 2009
Last Updated
July 2, 2017
Record last verified: 2009-06-08