Regional Blood FlowNCT00280501
Dopaminergic Modulation of Choroidal Blood Flow Changes During Dark/Light Transitions
A study testing Quetiapine (drug) and Sulpiride (drug) in people with Regional Blood Flow and Ocular Physiology, run by Medical University of Vienna at 1 site in Austria.
Trial summary
There is evidence from a variety of animal studies that choroidal blood flow is under neural control. By contrast, only little information is available from human studies. Recent results indicate that a light/dark transition is associated with a reduction in choroidal blood flow due to an unknown mechanism. Read more about this study
- Who is it for?
- Ages 18 to 35 years, men onlyHealthy volunteers can take part
- Conditions the study is for
- Regional Blood Flow, Ocular Physiology
- What is being tested?
- Quetiapine (drug) and Sulpiride (drug)
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 21 participants
- Where
- 1 siteAustria
- Study dates
- Aug 2005to Aug 2006
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 35 years
- Men only
- Healthy volunteers accepted
- Adult
Who may be able to join
- Men aged between 18 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.
Who cannot join
- 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
Trial locations and contacts
1 site in 1 country.
About this study
There is evidence from a variety of animal studies that choroidal blood flow is under neural control. By contrast, only little information is available from human studies. Recent results indicate that a light/dark transition is associated with a reduction in choroidal blood flow due to an unknown mechanism. We have shown that during unilateral dark/light transitions both eyes react with choroidal vasoconstriction strongly indicating a neural mechanism responsible for the blood flow changes.
Dopamine has been discussed as a chemical messenger for light adaptation. However, dopaminergic effects in the eye are not restricted to synaptic sites of release, but dopamine also diffuses to the outer retinal layers and pigment epithelium. Accordingly, dopaminergic effects also include a modulatory role on retinal vessel diameter and animal studies provide evidence for vasodilatory effects in the choroid. There is evidence that during darkness retinal and choroidal dopamine levels decrease. Accordingly, dopamine could provide a modulatory input to the light/dark transition induced changes of choroidal circulation. The aim of the present study is to test this hypothesis.
- Conditions
- Regional Blood Flow, Ocular Physiology
- Being tested
- Quetiapine (drug), Sulpiride (drug), Placebo
- Keywords
- Sulpiride, Quetiapine, Light/dark transition, Choroidal blood flow
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Quetiapine (drug)Drug
Quetiapine (Seroquel 100mg-film-coated tablet, AstraZeneca Vienna, Austria) Dose: 100 mg tablet oral single dose
Sulpiride (drug)Drug
Sulpiride (Dogmatil 200mg-tablet, Synthélabo Groupe, Le Plessis Robinson, France) Dose: one half of 200 mg tablet oral single dose
PlaceboDrug
Placebo
| Study group | Role | What they receive |
|---|---|---|
| 1 | Active comparator | Quetiapine Receives: Drug: Quetiapine (drug); Drug: Sulpiride (drug); Drug: Placebo |
| 2 | Active comparator | Sulpiride Receives: Drug: Quetiapine (drug); Drug: Sulpiride (drug); Drug: Placebo |
| 3 | Placebo comparator | Placebo Receives: Drug: Quetiapine (drug); Drug: Sulpiride (drug); Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
choroidal blood flow
Measured: in total 3x 3 hours
fundus pulsation amplitude
Measured: in total 3 x 3 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Jan 2006 (estimated)
- Study startAug 2005
- Primary completionAug 2006
- Study completionAug 2006
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Regional Blood FlowStudies of the same condition, open and under way.
- More trials run by Medical University of ViennaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 21 participants (actual)
Sponsor and investigators
- Lead sponsor
- Medical University of Vienna
- Sponsor type
- University, hospital or other
- Investigators
- Gabriele Fuchsjaeger-Mayrl, MD, Principal investigator, Department of Clinical Pharmacology
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00280501
- Sponsor's protocol ID
- OPHT-160905
- Status last verified
- Jul 2008
- First submitted
- 19 Jan 2006
- Last updated
- 9 Jul 2008
- Results posted
- No
- Data monitoring committee
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 9 Jul 2008. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Dopaminergic Modulation of Choroidal Blood Flow Changes During Dark/Light Transitions
- ClinicalTrials.gov ID
- NCT00280501
- Acronym / sponsor ID
- OPHT-160905
- Conditions
- Regional Blood Flow, Ocular Physiology
- Keywords
- Sulpiride, Quetiapine, Light/dark transition, Choroidal blood flow
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 21 participants (actual)
- Lead sponsor
- Medical University of ViennaUniversity, hospital or other
- Study start
- Aug 2005
- Primary completion
- Aug 2006 (actual)
- Study completion
- Aug 2006 (actual)
- First posted
- 23 Jan 2006 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
There is evidence from a variety of animal studies that choroidal blood flow is under neural control. By contrast, only little information is available from human studies. Recent results indicate that a light/dark transition is associated with a reduction in choroidal blood flow due to an unknown mechanism. We have shown that during unilateral dark/light transitions both eyes react with choroidal vasoconstriction strongly indicating a neural mechanism responsible for the blood flow changes.
Dopamine has been discussed as a chemical messenger for light adaptation. However, dopaminergic effects in the eye are not restricted to synaptic sites of release, but dopamine also diffuses to the outer retinal layers and pigment epithelium. Accordingly, dopaminergic effects also include a modulatory role on retinal vessel diameter and animal studies provide evidence for vasodilatory effects in the choroid. There is evidence that during darkness retinal and choroidal dopamine levels decrease. Accordingly, dopamine could provide a modulatory input to the light/dark transition induced changes of choroidal circulation. The aim of the present study is to test this hypothesis.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Double blind (participant, investigator)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| 1 | Active comparator | Drug: Quetiapine (drug), Drug: Sulpiride (drug), Drug: PlaceboQuetiapine |
| 2 | Active comparator | Drug: Quetiapine (drug), Drug: Sulpiride (drug), Drug: PlaceboSulpiride |
| 3 | Placebo comparator | Drug: Quetiapine (drug), Drug: Sulpiride (drug), Drug: PlaceboPlacebo |
Who may qualify
- Ages
- 18 to 35 years
- Sex
- Male only
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Men aged between 18 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.
Key exclusion criteria (6 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Quetiapine (drug)Quetiapine (Seroquel 100mg-film-coated tablet, AstraZeneca Vienna, Austria) Dose: 100 mg tablet oral single dose | Drug | 1, 2, 3 |
| Sulpiride (drug)Sulpiride (Dogmatil 200mg-tablet, Synthélabo Groupe, Le Plessis Robinson, France) Dose: one half of 200 mg tablet oral single dose | Drug | 1, 2, 3 |
| PlaceboPlacebo | Drug | 1, 2, 3 |
Primary outcome
choroidal blood flow
Time frame: in total 3x 3 hours
fundus pulsation amplitude
Time frame: in total 3 x 3 hours
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Jul 2008.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Gabriele Fuchsjaeger-Mayrl, MD principal investigator
Department of Clinical Pharmacology
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Quetiapine (drug) and Sulpiride (drug) in people with Regional Blood Flow and Ocular Physiology, run by Medical University of Vienna at 1 site in Austria.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 9 Jul 2008. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Austria. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
choroidal blood flow (time frame: in total 3x 3 hours). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 9 Jul 2008; AzTrials last refreshed its copy on 6 Nov 2026.