The Effect of Imipramine on Early Information Processing

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00206999
Recruitment Status : Completed
First Posted : September 21, 2005
Last Update Posted : September 20, 2011
University of Copenhagen
Glostrup University Hospital, Copenhagen
The Danish Medical Research Council
Lundbeck Foundation
Information provided by (Responsible Party):
Birte Glenthoj, University of Copenhagen

Brief Summary:
We wanted to compare the relation of two different psychophysiological paradigms (PrePulse Inhibition of the startle response = PPI and P50 suppression) to each other. Additionally, we wanted to test the effect of the combined serotonin- and noradrenaline re-uptake inhibitor, imipramine, on these measures. The primary hypothesis was that PPI and P50 gating would not correlate with each other at baseline. The secondary hypothesis was that increased noradrenergic and serotonergic activity would disrupt PPI as well as P50 gating.

Condition or disease Intervention/treatment Phase
Healthy Volunteers Drug: imipramine Not Applicable

Detailed Description:
Schizophrenic patients exhibit impairments in filtering of sensory information, as can be assessed by use of prepulse inhibition (PPI) of the acoustic startle response and P50 suppression paradigms. In the treatment of negative symptoms or depressive syndromes during the course of schizophrenia antidepressants are often combined with antipsychotic medication. However, antidepressants increase monoaminergic activity, of which in turn it has been suggested to decrease sensory gating, although these presumptions are mostly based on results from animal studies. Currently, little is known about monoaminergic modulation of sensory filtering in humans, and the few reports that can be found in literature show discrepancies with animal studies. The current study was designed to study the effects of increased monoaminergic activity on sensory filtering and habituation of healthy volunteers. In a double-blind, placebo controlled cross-over design, twenty healthy male volunteers will receive either placebo or a dose of 50 mg of imipramine (a dual acting antidepressant), after which they will be tested in a P50 suppression-, a PPI-, and a habituation of the startle reflex paradigm.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 20 participants
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Diagnostic
Official Title: Early Information Processing in Healthy Controls: Studies on the Relation Between Two Different Paradigms (PPI and P50ERP) and Effects of Pharmacological Interventions
Study Start Date : September 2004
Actual Primary Completion Date : January 2006
Actual Study Completion Date : January 2006

Resource links provided by the National Library of Medicine

U.S. FDA Resources

Arm Intervention/treatment
Experimental: 1 Drug: imipramine
Either 50 mg of imipramine or placebo will be administered to healthy male volunteers

Primary Outcome Measures :
  1. Sensory gating [ Time Frame: Once, 1 hour after administration of capsule ]

Secondary Outcome Measures :
  1. PPI of the startle reflex [ Time Frame: once, one hour after administration ]
  2. P50 suppression [ Time Frame: once, one hour after administration ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 35 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Male subjects
  • Good Physical and Mental Health meeting criteria "never mentally ill", which will be evaluated with a medical history checklist, ECG
  • Non smokers

Exclusion Criteria:

  • Current use of any medication
  • Any subject who has received any investigational medication within 30 days prior to the start of this study
  • History of neurologic illness
  • History of psychiatric illness in first-degree relatives, evaluated with DSM-IV criteria
  • History of alcohol and drug abuse. Positive urine screening for amphetamine, cocaine, cannabis, or ecstasy.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00206999

Center for Neuropsychiatric Schizophrenia Research, University of Copenhagen, Psychiatric Center Glostrup
Glostrup, Denmark, DK-2600
Sponsors and Collaborators
Birte Glenthoj
University of Copenhagen
Glostrup University Hospital, Copenhagen
The Danish Medical Research Council
Lundbeck Foundation
Study Director: Birte Glenthoj, MD, DMSc. Center for Neuropsychiatric Schizophrenia Research, University of Copenhagen, Psychaitric Center Glostrup, Ndr. Ringvej, DK-2600 Glostrup, Denmark

Additional Information:
Responsible Party: Birte Glenthoj, Professor, University of Copenhagen Identifier: NCT00206999     History of Changes
Other Study ID Numbers: 363052-2
KF 01-305/99
KF 11-061/03
KF 11-068/03
KF 11-096/04
First Posted: September 21, 2005    Key Record Dates
Last Update Posted: September 20, 2011
Last Verified: September 2011

Keywords provided by Birte Glenthoj, University of Copenhagen:
P50 suppression

Additional relevant MeSH terms:
Antidepressive Agents, Tricyclic
Antidepressive Agents
Psychotropic Drugs
Adrenergic Uptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Adrenergic Agents
Neurotransmitter Agents
Physiological Effects of Drugs