Ocular Hemodynamic Effects of Nitrovasodilators in Healthy Subjects - Full Text View

Sponsored by:	Medical University of Vienna
Information provided by:	Medical University of Vienna
ClinicalTrials.gov Identifier:	NCT00810381

Purpose

Glaucoma, one of the most common causes of blindness, is associated with increased intraocular pressure (IOP) and optic nerve head ischemia.

Nitrovasodilators are discussed in the treatment of glaucoma. Nitrates relax smooth muscle cells in the vasculature by liberating the vasodilator nitric oxide. The IOP lowering potential and the vasodilator action in retinal and choroidal vessels of nitrates is still a matter of controversy. Previous studies on the ocular hemodynamic effects of nitrates showed partially contradicting results. In addition the IOP lowering effect of nitrates is still unclear.

However, recent studies show that long acting nitrates may preserve optic nerve deterioration and visual field loss.

Therefore, the role of nitrovasodilators in control of ocular blood flow and intraocular pressure has to be elucidated. For this purpose the investigators plan to test the hypothesis that nitrovasodilators improve ocular blood supply to the optic nerve head at doses which do not affect systemic hemodynamics.

Condition	Intervention
Glaucoma	Drug: Nitroglycerin Drug: Isosorbide-Dinitrate Drug: Sodium-nitroprusside Drug: Physiologic saline solution (control substance)

Genetics Home Reference related topics: early-onset glaucoma

MedlinePlus related topics: Glaucoma

Drug Information available for: Nitroglycerin Sodium nitroprusside Nitroprusside Isosorbide-5-mononitrate Isosorbide dinitrate Isosorbide

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Basic Science, Randomized, Double Blind (Subject, Investigator, Outcomes Assessor), Placebo Control, Crossover Assignment, Safety/Efficacy Study
Official Title:	Ocular Hemodynamic Effects of Nitrovasodilators in Healthy Subjects

Further study details as provided by Medical University of Vienna:

Primary Outcome Measures:

Optic disc blood flow (laser Doppler flowmetry) [ Time Frame: in total 24x on 4 study days ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

Intraocular pressure [ Time Frame: in total 8x in 4 study days ] [ Designated as safety issue: No ]
Choroidal blood flow (laser Doppler flowmetry) [ Time Frame: in total 24x on 4 study days ] [ Designated as safety issue: No ]
Fundus pulsation amplitude in the macula (laser interferometry) [ Time Frame: in total 24x on 4 study days ] [ Designated as safety issue: No ]
Fundus pulsation amplitude in the optic disc (laser interferometry) [ Time Frame: in total 24x on 4 study days ] [ Designated as safety issue: No ]
Blood pressure, pulse rate [ Time Frame: on 4 study days ] [ Designated as safety issue: Yes ]

Enrollment:	14
Study Start Date:	January 1999
Study Completion Date:	June 1999
Primary Completion Date:	June 1999 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1: Active Comparator Nitroglycerin: (Perlinganit, Nycomet Heilmittelwerke, Vienna, Austria): 0, 0.25, 0.5, 1, 1.5 and 2 µg/kg/min, each infusion step for 20 minutes	Drug: Nitroglycerin intravenous infusion; 0, 0.125, 0.25, 0.5, 1 and 2 µg/kg/min; 20 minutes per infusion step
2: Active Comparator Isosorbide-Dinitrate: (Isoket 0,1 %, Gebro Broschek, Fieberbrunn, Austria): 0, 0.5, 1, 2, 4 and 6 µg/kg/min , each infusion step for 20 minutes	Drug: Isosorbide-Dinitrate intravenous infusion; 0, 0.5, 1, 2, 4, and 6 µg/kg/min; 20 minutes per infusion step
3: Active Comparator Sodium-Nitroprusside: (Nipruss, Sanol-Schwarz, Monheim, Germany): 0, 0.25, 0.5, 1, 2 and 4 µg/kg/min, each infusion step for 20 minutes	Drug: Sodium-nitroprusside intravenous infusion; 0, 0.25, 0.5, 1, 2, and 4 µg/kg/min; 20 minutes per infusion step
4: Placebo Comparator Physiologic saline solution	Drug: Physiologic saline solution (control substance) intravenous infusion, infusion period 120 minutes

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 (Must et al. 1991)
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
History of migraine
Blood donation during the previous 3 weeks

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00810381

Locations

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

Sponsors and Collaborators

Medical University of Vienna

Investigators

Principal Investigator:

Hans-Georg Eichler, MD

Department of Clinical Pharmacology, Medical University of Vienna

More Information

No publications provided

Responsible Party:	Department of Clinical Pharmacology, Medical University of Vienna ( Hans-Georg Eichler, MD )
Study ID Numbers:	OPHT-211097
Study First Received:	December 17, 2008
Last Updated:	December 17, 2008
ClinicalTrials.gov Identifier:	NCT00810381 History of Changes
Health Authority:	Austria: Agency for Health and Food Safety

Keywords provided by Medical University of Vienna:

Nitrovasodilators
ONH blood flow
Choroidal blood flow
Nitroglycerin

Isosorbide Dinitrate
Sodium nitroprusside
Laser-Doppler Flowmetry
Regional Blood Flow

Study placed in the following topic categories:

Isosorbide
Vasodilator Agents
Isosorbide-5-mononitrate
Eye Diseases
Diuretics
Isosorbide Dinitrate
Healthy
Cardiovascular Agents

Antihypertensive Agents
Nitric Oxide Donors
Nitroglycerin
Nitric Oxide
Glaucoma
Nitroprusside
Ocular Hypertension
Hypertension

Additional relevant MeSH terms:

Isosorbide
Vasodilator Agents
Molecular Mechanisms of Pharmacological Action
Isosorbide-5-mononitrate
Diuretics, Osmotic
Eye Diseases
Physiological Effects of Drugs
Diuretics
Isosorbide Dinitrate
Cardiovascular Agents

Antihypertensive Agents
Pharmacologic Actions
Nitric Oxide Donors
Nitroglycerin
Natriuretic Agents
Glaucoma
Therapeutic Uses
Nitroprusside
Ocular Hypertension

ClinicalTrials.gov processed this record on May 07, 2009