The Influence of Glutamate on Memory in Humans

December 2, 2014 updated by: Rene Hurlemann, University Hospital, Bonn

The NMDA Receptor Co-agonist D-cycloserine Accelerates Associative Learning in the Human Hippocampal CA Region

The hippocampus is particularly laden with n-methyl-d-aspartate (NMDA) receptors, and is at the same time one of the most important sites in declarative memory. The rationale of this study is that the NMDA partial agonist D-Cycloserine will promote learning compared to a placebo. On the other hand, the NMDA receptor antagonist Memantine might lead to reduced memory. We believe that the influence of NMDA receptors on memory can be determined via acute co-activation of the NMDA receptors with Cycloserine® (King Pharmaceuticals Ltd, active ingredient: DCycloserin, dose: 250 mg) and Memantine (Axura®, Merz, active ingredient: Memantine, dose: 20 mg)on both a behavioral and functional (fMRI) level.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
120

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Germany
    • NRW
      • Juelich, NRW, Germany, 52428
        • Forschungszentrum Juelich GmbH

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years to 35 years (Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • German native language or native language level
  • Able to give written informed consent
  • right-handed

Exclusion Criteria:

  • inability to give written informed consent, underaged minors, contractually incapable persons, persons in legal custody
  • any psychiatric, neurological or internal illness
  • hematoporphyria (enzyme sickness)
  • intake of medication (except oral contraceptives)
  • simultaneous participation in other clinical studies
  • hypersensitivity to Memantine or other anti-dementia substances, or to D-Cycloserine
  • alcohol abuse
  • epilepsy
  • depression
  • serious anxiety or psychosis
  • serious kidney insufficiency
  • intake of Ethionamide or Isoniazide
  • pregnancy or women who are nursing
  • liver or kidney problems
  • intake of NMDA-antagonists, such as Amantadine, Ketamine, or Dextromethorphan
  • vegetarians
  • stomach ulcer, if treated with medication
  • renal tubular acidosis
  • urinary infections (with proteus bacteria)
  • recent heart attack, heart failure, or uncontrolled high blood pressure
  • intake of L-Dopa, dopaminergic agonists, and anticholinergics
  • intake of barbiturates, spasmolytics, Phenytoin, Amantadine, oral coagulators, warfarin, HCT (Hydrochlorothiazide)
  • heart or cranial operations
  • pacemaker, medication pump (such as insulin pump), hearing aid, removable prosthodontics
  • metal in or on body (such as acupuncture needles, artificial limbs, stents, metal splints, clips, implanted electrodes, tattoos, or piercings)
  • claustrophobia

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Placebo Comparator: Sugar pill, behavioral glutamic acid
Placebo condition for D-Cycloserine
Drug: Sugar pill
250 mg, one dose, 60 min prior
Other Names:
  • Placebo condition for D-Cycloserine, fMRI
Drug: Sugar pill
20 mg, one dose, 8 hours prior
Other Names:
  • Placebo condition Memantine, fMRI
Placebo Comparator: Sugar pill, fMRI, glutamic acid
Placebo condition for D-Cycloserine, fMRI
Drug: Sugar pill
250 mg, one dose, 60 min prior
Other Names:
  • Placebo condition for D-Cycloserine, fMRI
Drug: Sugar pill
20 mg, one dose, 8 hours prior
Other Names:
  • Placebo condition Memantine, fMRI
Placebo Comparator: Sugar pill, memantine, behavioral
Placebo condition Memantine, behavioral
Drug: Sugar pill
250 mg, one dose, 60 min prior
Other Names:
  • Placebo condition for D-Cycloserine, fMRI
Drug: Sugar pill
20 mg, one dose, 8 hours prior
Other Names:
  • Placebo condition Memantine, fMRI
Placebo Comparator: Sugar pill, memantine, fMRI
Placebo condition Memantine, fMRI
Drug: Sugar pill
250 mg, one dose, 60 min prior
Other Names:
  • Placebo condition for D-Cycloserine, fMRI
Drug: Sugar pill
20 mg, one dose, 8 hours prior
Other Names:
  • Placebo condition Memantine, fMRI
Active Comparator: D-Cycloserine behavioral
Drug: Glutamic Acid
250 mg, one dose, 60 minutes prior
Other Names:
  • D-Cycloserine, King Pharmaceuticals
Active Comparator: D-Cycloserine, fMRI
Drug: Glutamic Acid
250 mg, one dose, 60 minutes prior
Other Names:
  • D-Cycloserine, King Pharmaceuticals
Active Comparator: Memantine, behavioral
Drug: Memantine
20 mg, one dose, 8 hours prior
Other Names:
  • Axura, Merz
Active Comparator: Memantine, fMRI
Drug: Memantine
20 mg, one dose, 8 hours prior
Other Names:
  • Axura, Merz

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Time Frame
fMRI during learning task
Time Frame: once at drug administration
once at drug administration

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University Hospital, Bonn

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
June 1, 2008

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
August 1, 2011

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
August 1, 2011

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
September 18, 2009

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
September 18, 2009

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 21, 2009

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
December 3, 2014

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
December 2, 2014

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
December 1, 2014

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • RH999

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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