Effect of Levodopa on Human Multifocal Electroretinogram

NCT00812760 | Completed Phase 4

• 1 other identifier: OPHT-220501
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Retinal Diseases

Keywords

Electroretinography; levodopa

Outcome Measures

Primary Outcomes (1)

• Retinal activity (mERG amplitude)

  5 measurements on both study days

Secondary Outcomes (2)

• Retinal activity (mERG latency)

  5 measurements on both study days

• Dopamine and levodopa plasma levels

  on both study days

Study Arms (1)

1

EXPERIMENTAL

Drug: levodopa

Interventions

levodopa DRUG

1 tablet of 200 mg levodopa plus 50 mg benserazide

Also known as: Madopar

1

Eligibility Criteria

• Age: 19 Years - 35 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• 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

You may not qualify if:

• 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

Sponsors & Collaborators

• Medical University of Vienna: lead

Study Sites (1)

Department of Clinical Pharmacology, Medical University of Vienna

Vienna, 1090, Austria

Location

MeSH Terms

Conditions

Retinal Diseases

Interventions

Levodopa; benserazide, levodopa drug combination

Condition Hierarchy (Ancestors)

Eye Diseases

Intervention Hierarchy (Ancestors)

Dihydroxyphenylalanine; Catecholamines; Amines; Organic Chemicals; Catechols; Phenols; Benzene Derivatives; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Phenylalanine; Amino Acids, Aromatic; Amino Acids, Cyclic; Amino Acids; Amino Acids, Peptides, and Proteins; Tyrosine

Study Officials

• Michael Wolzt, MD

  Department of Clinical Pharmacology, Medical University of Vienna

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: December 18, 2008
• First Posted: December 22, 2008
• Study Start: October 1, 2001
• Primary Completion: October 1, 2003
• Study Completion: October 1, 2003
• Last Updated: December 22, 2008

Record last verified: 2008-12

Locations

AU (1)