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Serotonin Transporters in Obsessive-Compulsive-Related Disorders

This study has been completed.
Information provided by:
National Institutes of Health Clinical Center (CC) Identifier:
First received: May 12, 2004
Last updated: January 24, 2017
Last verified: April 9, 2007

This study will compare serotonin transporters in patients with obsessive-compulsive disorder (OCD) and healthy volunteers in order to better understand the role of serotonin in OCD. Serotonin is a chemical in the brain that transmits nerve impulses. The serotonin transporter (SERT) is a protein that regulates serotonin levels in the brain.

Normal, healthy volunteers and patients with OCD between 18 and 50 years of age and in overall good health may be eligible for this study. Candidates are screened with a medical history, physical examination, blood and urine tests, and a psychological interview and tests related to OCD symptoms. Participants undergo the following tests:

  • Positron emission tomography (PET) scanning: For this test, subjects lie on the scanner bed, wearing special masks that are fitted to their heads and attached to the beds to help keep their heads still during the procedure. An 8-minute "transmission" scan is done to provide measures of the brain that will help calculate information obtained from subsequent scans. Then, a radioactive tracer is injected into a catheter (plastic tube) placed in the arm. The scan produces images of the serotonin transporters in the brain. Pictures are taken for about 2 hours, while the subject lies still on the scanner bed.
  • Magnetic resonance imaging (MRI) scanning: An MRI scan of the brain is done within 1 year of the PET scan-that is, up to 1 year before or 1 year after the PET scan. MRI uses a magnetic field and radio waves to produce images of body tissues and organs. For this procedure, the patient lies on a table that is moved into the scanner (a narrow cylinder), wearing earplugs to muffle loud knocking and thumping sounds that occur during the scanning process. The procedure lasts about 1 hour, during which the patient will be asked to lie still for up to a few minutes at a time.
  • Genotyping: Subjects provide a blood sample (4 tablespoons) for DNA testing to look for genes or gene regions that may contribute to serotonin activity. This may lead to a better understanding of the genetic underpinnings of the serotonin system that influence mood, movement, and addiction.

Obsessive-Compulsive Disorder

Study Type: Observational
Official Title: PET Imaging of Monoamine Transporters in OCD-related Disorders

Resource links provided by NLM:

Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment: 30
Study Start Date: May 10, 2004
Estimated Study Completion Date: April 9, 2007
Detailed Description:
Evidence suggests that the symptoms of obsessive-compulsive disorder (OCD) arise from dysfunction of both the serotonergic and dopaminergic neurotransmitter systems. These two neurotransmitter systems are presumed to play a key modulatory role at the limbic-motor interface of the fronto-subcortical circuitry. However, in vivo knowledge linking the serotonergic and dopaminergic systems to OCD and OCD-related disorders is limited. In the current protocol, we plan to use PET to image the serotonin transporter (SERT) within the new radioligand [11C]DASB, in order to delineate regional abnormalities in SERT binding in drug-naive or drug-free OCD patients in comparison to healthy volunteers. In addition, we plan to examine the relationship between the regional PET measures of SERT and clinical severity measures of OCD. The goal of the present study is, thus, to further our understanding of the role of the serotonergic system in the pathophysiology of OCD.

Ages Eligible for Study:   18 Years to 65 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Patients and Controls:

Age: 18-65.

Patients- DSM-IV criteria for OCD.

Controls- not required

Patients and Controls:

Good health, with absence of serious medical illnesses, such as congestive heart failure, diabetes, kidney failure, epilepsy or cancer.


Healthy Subjects:

History or current DSM-IV Axis I diagnostic criteria.

Patients and Controls:

Current diagnosis of major depressive disorder.

Patients and Controls:

Psychotropic medications, including SSRIs and antipsychotic medications. Drug free period must be greater than 4 weeks.

Patients and Controls:


Patients and Controls:

Pregnancy. Women with child bearing potential.

Patients and Controls:

Prior participation in other research protocols within the past year such that a radiation exposure together with the present study would exceed the annual limits.

Patients and Controls:

Any condition that increases risk for MRI (e.g., pacemaker, metallic foreign body in the eye, etc.)

  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00082550

United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institute of Mental Health (NIMH)
  More Information

Publications: Identifier: NCT00082550     History of Changes
Other Study ID Numbers: 040180
Study First Received: May 12, 2004
Last Updated: January 24, 2017

Keywords provided by National Institutes of Health Clinical Center (CC):
Serotonin Transporter
Brain Imaging
Obsessive-Compulsive Disorder
Obsessive Compulsive Disorder
Healthy Volunteer

Additional relevant MeSH terms:
Compulsive Personality Disorder
Obsessive-Compulsive Disorder
Compulsive Behavior
Personality Disorders
Mental Disorders
Anxiety Disorders
Pathologic Processes
Impulsive Behavior
Serotonin Receptor Agonists
Serotonin Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs processed this record on April 26, 2017