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Effect of GTN and Diamox Measured by BOLD-Response.

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified August 2006 by Danish Headache Center.
Recruitment status was:  Recruiting
Information provided by:
Danish Headache Center Identifier:
First received: August 11, 2006
Last updated: NA
Last verified: August 2006
History: No changes posted

In healthy subjects different cerebral haemodynamic values wished to be determined after infusion of the NO donor Glyceryl trinitrate (GTN) and Diamox. The different values we wish to determine are:

  • Blood-oxygenation-level-Dependent-signal (BOLD-signal) after visual stimulation.
  • Changes in the diameter of a. cerebri media.
  • Changes in the regional and global cerebral blodd flow (CBF) with the help of the arterial Spin labeling (ASL) method.

Condition Intervention
Drug: Glyceryl trinitrate, azetazolamide

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double-Blind
Primary Purpose: Educational/Counseling/Training
Official Title: The Effect of Glyceryl Trinitrate and Diamox on Blood-Oxygenation-Level-Dependent.Signal (BOLD-Signal) and Cerebral Haemodynamics With the Use of a 3-Tesla MRI-Scan.

Resource links provided by NLM:

Further study details as provided by Danish Headache Center:

Primary Outcome Measures:
  • Changes in BOLD response
  • Changes in a. cerebri media diameter
  • Changes in CBF

Secondary Outcome Measures:
  • headache score

Estimated Enrollment: 12
Estimated Study Completion Date: May 2007
Detailed Description:

Experimental headache models give a unike opportunity to study pathophysiological mechanisms of prim. headache types such as migraine. Previous studies have used different methods that have had limitations and none of them have had the opportunity to study neuronal activation. But that is possible with the application of functional magnetic resonance (fMRI).

Before we apply fMRI to our experimental headache models it is needed to determine how the BOLD response is influenced and changed by the infusion of different drugs such as the NO donor Glyceryl Trinitrate (GTN) and Diamox (acetazolamide). It is known that GTN causes dilation of the cerebral arteries without having any effect on the regional cerebral blood flow. It is not known what effect GTN has on the BOLD response. Diamox (azetazolamide) increases the CBF but it is uncertain what effect the drug has on the BOLD response. Previous studies disagree gravely on this point.

In this study we will be giving infusion of GTN and Diamox in healty subjects to determine:

  • Blood-oxygenation-level-Dependent-signal (BOLD-signal) after visual stimulation.
  • Changes in the diameter of a. cerebri media.
  • Changes in the regional and global cerebral blodd flow (CBF) with the help of the arterial Spin labeling (ASL) methode.

For the study we will be using a 3-Tesla MRI-scan.


Ages Eligible for Study:   18 Years to 55 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • healthy subjects
  • age 18-55 years
  • weight 50-100 kg

Exclusion Criteria:

  • Tension type headache more the once per month.
  • other types of headache
  • Daily use of medication other the birthcontrol pills.
  • Pregnant or lactating women.
  • headache on the examination date.
  • contraindications to MRI-scan.
  • hypotension or hypertension.
  • mental illness og substance abuse.
  • other significant conditions determined by the examining doctor.
  Contacts and Locations
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Please refer to this study by its identifier: NCT00363792

Contact: Mohammad Sohail Asghar, MD +4543232161

Danish Headache Center Recruiting
Glostrup, Denmark, 2770
Contact: Mohammad Sohail Asghar, MD    +4543232161   
Principal Investigator: Mohammad Sohail Asghar, MD         
Sponsors and Collaborators
Danish Headache Center
Study Chair: Messoud Ashina, MD, Phd, Danish Headache Center
  More Information Identifier: NCT00363792     History of Changes
Other Study ID Numbers: KA-20060085
Study First Received: August 11, 2006
Last Updated: August 11, 2006

Keywords provided by Danish Headache Center:
Healthy subjects

Additional relevant MeSH terms:
Vasodilator Agents processed this record on April 26, 2017