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Effect of Levodopa on Human Multifocal Electroretinogram

This study has been completed.
Information provided by:
Medical University of Vienna Identifier:
First received: December 18, 2008
Last updated: December 19, 2008
Last verified: December 2008
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 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double Blind (Participant, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Effect of Levodopa on Human Multifocal Electroretinogram

Resource links provided by NLM:

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 ]

Secondary Outcome Measures:
  • Retinal activity (mERG latency) [ Time Frame: 5 measurements on both study days ]
  • Dopamine and levodopa plasma levels [ Time Frame: on both study days ]

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
Experimental: 1 Drug: levodopa
1 tablet of 200 mg levodopa plus 50 mg benserazide
Other Name: Madopar


Ages Eligible for Study:   19 Years to 35 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

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
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Please refer to this study by its identifier: NCT00812760

Department of Clinical Pharmacology, Medical University of Vienna
Vienna, Austria, 1090
Sponsors and Collaborators
Medical University of Vienna
Principal Investigator: Michael Wolzt, MD Department of Clinical Pharmacology, Medical University of Vienna
  More Information

Responsible Party: Michael Wolzt, Department of Clinical Pharmacology, Medical University of Vienna Identifier: NCT00812760     History of Changes
Other Study ID Numbers: OPHT-220501
Study First Received: December 18, 2008
Last Updated: December 19, 2008

Keywords provided by Medical University of Vienna:

Additional relevant MeSH terms:
Retinal Diseases
Eye Diseases
Antiparkinson Agents
Anti-Dyskinesia Agents
Dopamine Agents
Neurotransmitter Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs processed this record on April 27, 2017