Does eNOS Gene Polymorphism Play a Role in the Maintenance of Basal Vascular Tone in the Choroid or Optic Nerve Head? - Full Text View

Sponsored by:	Medical University of Vienna
Information provided by:	Medical University of Vienna
ClinicalTrials.gov Identifier:	NCT00708357

Purpose

Nitric oxide (NO) is a potent endothelium-derived vasodilatator that plays a major role in the control of ocular blood flow. Endothelial NO synthase (eNOS) is one of three isoforms of NOS producing NO through hydroxylation of L-arginine. The eNOS gene is located on the long arm of chromosome 7, and different polymorphic variations have been identified. These single nucleotide polymorphisms (sNP´s) have the ability to change transcription activity and therefore enzyme levels. Recent data indicate that the T -786C polymorphism (especially the homozygous variant) is associated with reduced eNOS activity and consequently impaired NO production.

In the present study the investigators want to investigate if the T -786C eNOS gene polymorphism determines choroidal and optic nerve head blood flow.

Condition	Intervention	Phase
Ocular Physiology Regional Blood Flow	Drug: NG-monomethyl-L-arginine	Phase 0

Drug Information available for: Arginine Arginine hydrochloride omega-N-Methylarginine

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Diagnostic, Non-Randomized, Single Blind (Investigator), Uncontrolled, Parallel Assignment, Safety/Efficacy Study
Official Title:	Does eNOS Gene Polymorphism Play a Role in the Maintenance of Basal Vascular Tone in the Choroid or Optic Nerve Head?

Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:

Genotyping [ Time Frame: performed during the first year before measurements ] [ Designated as safety issue: No ]

Estimated Enrollment:	18
Study Start Date:	May 2005
Estimated Study Completion Date:	May 2009
Estimated Primary Completion Date:	May 2009 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1 homozygous mutant: CC allele of the eNOS T-786C gene	Drug: NG-monomethyl-L-arginine intravenous administration, bolus over 5 minutes, dosage 6mg/kg
2 homozygous mutant: TT allele of the eNOS T-786C gene	Drug: NG-monomethyl-L-arginine intravenous administration, bolus over 5 minutes, dosage 6mg/kg

Eligibility

Ages Eligible for Study:	19 Years and older
Genders Eligible for Study:	Male
Accepts Healthy Volunteers:	Yes

Criteria

Inclusion Criteria:

Men aged between 19 and 35 years, nonsmokers
Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
Homozygous variants of the T -786C genotyping (CC or TT)
Normal ophthalmic findings, ametropia less than 3 diopters

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: NCT00708357

Contacts

Contact: Gerhard Garhöfer, MD

00431 40400 2981

gerhard.garhoefer@meduniwien.ac.at

Locations

Austria
Department of Clinical Pharmacology	Recruiting
Vienna, Austria
Contact: Gerhard Garhöfer, MD 00431 40400 2981 gerhard.garhoefer@meduniwien.ac.at

Sponsors and Collaborators

Medical University of Vienna

Investigators

Principal Investigator:

Michael Wolzt, MD

Department of CLinical Pharmacology

More Information

Responsible Party:	Department of Clinical Pharmacology, Medical University of Vienna ( Michael Wolzt )
Study ID Numbers:	OPHT-311004
Study First Received:	June 26, 2008
Last Updated:	December 22, 2008
ClinicalTrials.gov Identifier:	NCT00708357
Health Authority:	Austria: Agency for Health and Food Safety

Keywords provided by Medical University of Vienna:

eNOS Gene Polymorphism
ocular blood flow

Study placed in the following topic categories:

Omega-N-Methylarginine

Additional relevant MeSH terms:

Molecular Mechanisms of Pharmacological Action
Enzyme Inhibitors
Pharmacologic Actions

ClinicalTrials.gov processed this record on January 14, 2009