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Updated: Jun 19, 2026
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Assessment of Human Adipose Tissue Microvascular Function Using Videomicroscopy
Published on: September 29, 2017
Acetazolamide-induced vasodilation does not inhibit the visually evoked flow response
Yaniv Yonai1, Neta Boms, Sandor Molnar
1Department of Neurology, University of Debrecen, Debrecen H-4032, Hungary.
Summary
Acetazolamide (AZ) does not inhibit neurovascular coupling in the brain. Cerebral blood flow adaptation to neuronal activity remains intact even with AZ-induced vasodilation.
Area of Science:
- Neuroscience
- Cerebrovascular Physiology
Background:
- Assessing cerebral vasodilator function is crucial, but mechanisms remain unclear.
- Acetazolamide (AZ) is a potent vasodilator, but its effect on neurovascular coupling is unknown.
Purpose of the Study:
- To investigate if acetazolamide (AZ) inhibits neurovascular coupling.
- To examine visually evoked flow parameters before and after AZ administration.
Main Methods:
- Ten healthy subjects underwent transcranial Doppler assessment.
- Pulsatility index and peak systolic flow velocity were recorded in posterior cerebral arteries.
- Measurements were taken before and after intravenous administration of 15 mg/kg AZ.
Main Results:
- No significant difference in visually evoked flow velocity time courses before and after AZ.
- Visual stimulation increased flow velocity and decreased pulsatility index, even with maximal AZ effect.
- A dose of 15 mg/kg AZ did not achieve maximal cerebral vasodilation.
Conclusions:
- Neurovascular coupling is preserved despite AZ-induced vasodilation.
- Cerebral blood flow adapts to neuronal activity independently of other vasodilation processes.
- The tested AZ dose is insufficient to determine maximal cerebral vasodilation.
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