Does eNOS Gene Polymorphism Play a Role in the Maintenance of Basal Vascular Tone in the Choroid or Optic Nerve Head?
Study Details
Study Description
Brief Summary
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 or Disease | Intervention/Treatment | Phase |
---|---|---|
Early Phase 1 |
Study Design
Arms and Interventions
Arm | Intervention/Treatment |
---|---|
Other: 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
Other Names:
|
Other: 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
Other Names:
|
Outcome Measures
Primary Outcome Measures
- Genotyping [performed during the first year before measurements]
Eligibility Criteria
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
Locations
Site | City | State | Country | Postal Code | |
---|---|---|---|---|---|
1 | Department of Clinical Pharmacology | Vienna | Austria |
Sponsors and Collaborators
- Medical University of Vienna
Investigators
- Principal Investigator: Michael Wolzt, MD, Department of CLinical Pharmacology
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- OPHT-311004