Effect of Levodopa on Human Multifocal Electroretinogram - Full Text View

Sponsored by:	Medical University of Vienna
Information provided by:	Medical University of Vienna
ClinicalTrials.gov Identifier:	NCT00812760

Purpose

It is known that dopamine is a functional neuromodulator at several levels of the visual system. Dopamine seems to be involved in the organization of the ganglion cell and the bipolar cell receptive fields and modulation of physiological activity of photoreceptors. There is evidence for the functional significance of dopaminergic modulation of visual sensitivity in humans which confirms the hypothesis that dopamine plays an important role in retinal light adaptation as well as in motion and contrast sensitivity function. The electrophysiological effects of dopamine, various dopamine antagonist and levodopa in animals and humans have been investigated by means of visual evoked potentials and electroretinograms. The multifocal ERG technique, developed by Sutter et al. allows a rapid, simultaneous recording of focal ERGs from multiple retinal locations. Although this technique is relatively new, it has already provided insights into the mechanisms of retinal diseases (e.g. involvement of visual system in Parkinson disease), but until now there is no data on influence of dopaminergic substances on mERG.

Condition	Intervention	Phase
Retinal Diseases	Drug: levodopa	Phase IV

MedlinePlus related topics: Retinal Disorders

Drug Information available for: Levodopa Benserazide

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Double Blind (Subject, Investigator, Outcomes Assessor), Placebo Control, Crossover Assignment, Safety/Efficacy Study
Official Title:	Effect of Levodopa on Human Multifocal Electroretinogram

Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:

Retinal activity (mERG amplitude) [ Time Frame: 5 measurements on both study days ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Retinal activity (mERG latency) [ Time Frame: 5 measurements on both study days ] [ Designated as safety issue: No ]
Dopamine and levodopa plasma levels [ Time Frame: on both study days ] [ Designated as safety issue: No ]

Enrollment:	20
Study Start Date:	October 2001
Study Completion Date:	October 2003
Primary Completion Date:	October 2003 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1: Experimental	Drug: levodopa 1 tablet of 200 mg levodopa plus 50 mg benserazide

Eligibility

Ages Eligible for Study:	19 Years to 35 Years
Genders Eligible for Study:	Male
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

Men aged between 19 and 35 years, nonsmokers
Body mass index between 15th and 85th percentile
Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
Normal laboratory values unless the investigator considers an abnormality to be clinically irrelevant
Normal ophthalmic findings, ametropia < 3 Dpt

Exclusion Criteria:

Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
Treatment in the previous 3 weeks with any drug
Symptoms of a clinically relevant illness in the 3 weeks before the first study day
History of hypersensitivity to the trial drug or to drugs with a similar chemical structure
History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with, distribution, metabolism or excretion of study drugs
Blood donation during the previous 3 weeks

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00812760

Locations

Austria
Department of Clinical Pharmacology, Medical University of Vienna
Vienna, Austria, 1090

Sponsors and Collaborators

Medical University of Vienna

Investigators

Principal Investigator:

Michael Wolzt, MD

Department of Clinical Pharmacology, Medical University of Vienna

More Information

Responsible Party:	Department of Clinical Pharmacology, Medical University of Vienna ( Michael Wolzt )
Study ID Numbers:	OPHT-220501
Study First Received:	December 18, 2008
Last Updated:	December 19, 2008
ClinicalTrials.gov Identifier:	NCT00812760
Health Authority:	Austria: Agency for Health and Food Safety

Keywords provided by Medical University of Vienna:

Electroretinography
levodopa

Study placed in the following topic categories:

Levodopa
Dopamine
Eye Diseases
Benserazide
Retinal Diseases

Additional relevant MeSH terms:

Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Anti-Dyskinesia Agents
Therapeutic Uses
Physiological Effects of Drugs

Antiparkinson Agents
Dopamine Agents
Central Nervous System Agents
Pharmacologic Actions

ClinicalTrials.gov processed this record on January 13, 2009