Increased nitroglycerin-mediated vasodilation in migraineurs without aura in the interictal period

DOI: https://doi.org/10.1007/s10396- 018- 0880- 3

Abstract-Summary We investigated flow-mediated vasodilatation (FMD) and nitroglycerin-mediated vasodilatation (NMD) of the brachial artery by means of a key molecular mediator, NO, in patients with migraine without aura in the interictal period whether the abnormality is found.

There was no significant difference in brachial artery diameter between migraineurs and nonmigraineurs (3.39 ± 0.68 vs 3.89 ± 0.67  mm, respectively; p = 0.083).

A significant difference in FMD was not found between migraineurs and nonmi-

graineurs (6.94 ± 5.72% vs 6.08 ± 2.98%, respectively; p = 0.651).

NMD in migraineurs was significant higher than that in nonmigraineurs

(21.56 ± 7.36% vs 14.23 ± 7.41%, respectively; p = 0.024).

We think that patients with migraine without aura in the interictal period have selective sensitivity in dilator response to nitroglycerin and may have systemic NO sensitivity.

Extended: There was no significant difference between migraineurs and nonmi-

graineurs in relation to both right and left IMT-Cmax, baPWV, and ABI.

We think that NO sensitivity to NTG in patients with migraine without aura is a specific and selective response, and that patients with migraine may have systemic NO sensitivity to NTG.

We believe that patients with migraine without aura in the interictal period have a selective sensitivity in dilator response to NTG and may have systemic NO sensi- tivity to NTG.

Introduction Decreased FMD [267] and increased NMD and decreased FMD [268] have been described in reports of patients with migraine without aura in the interictal period.

When systemic NTG, an NO donor, was administrated to patients with migraine without aura in the interictal period, an increased sensitivity to NO was demon- strated [269, 270].

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2 Mechanisms

NTG and NP act directly at the level of the arterial smooth muscle cell and pro- duce an endothelium-independent dilatation response, different reactions between NTG and NP have been recognized in migraineurs without aura in the interic- tal phase.

We suggest that patients with migraine without aura in the interictal period have selective sensitivity in dilator response to NTG and may have systemic NO sensitiv- ity to NTG.

Materials and Methods On the day of the study, patients had been free from migraine attacks for at least 5 days.

FMD of the brachial artery was determined using a high-resolution B-mode ultrasonographic system (UNEXEF 18G, UNEX, Nagoya, Japan) with a linear transducer with a mid frequency of 7.5 MHz, using the technique described in a previous report [271].

FMD and NMD were expressed as the change in the post-stimulus (flow and

nitrate mediated) diameter as a percentage of the baseline diameter.

The intima-media thickness (IMT) of the bilateral common carotid arteries (CCA) was measured by ultrasonography with a 10-MHz probe using an ultrasound system (Aplio SSA-700A, Toshiba Medical Systems, Tochigi, Japan).

baPWV was measured using a volume-plethysmographic apparatus (form PWV/ ABI, Colin, Komaki, Japan), and ankle brachial pressure index (ABI), which is use- ful for detecting peripheral artery disease, was measured simultaneously with these machines in accordance with a described method [272].

Results There was no significant difference in brachial artery diameter (BAD) between migraineurs and nonmigraineurs (3.39  ±  0.68 vs 3.89  ±  0.67  mm, respectively; p = 0.083).

FMD examination showed no significant difference between migraineurs and

nonmigraineurs (6.94 ± 5.72% vs 6.08 ± 2.98%, respectively; p = 0.651).

Discussion Increased NMD and decreased FMD in the brachial artery were observed in patients with migraine without aura in the interictal period [268].

When systemic NTG, an NO donor, was administrated to patients with migraine without aura in the interictal period, an increased sensitivity to NO was demon- strated [269, 270].

Yetkin and others [268] reported decreased FMD and increased NMD in patients

with migraine without aura in the interictal period.

Vanmolkot and others indicated that a smaller diameter of muscular artery including the brachial artery and decreased compliance are associated with a gener- alized increase in vascular smooth muscle tone in patients with migraine with or without aura [273].

Our data indicate that endothelial dysfunction may not underlie the pathogenesis of increased NMD, as previously reported [268], and that the sensitive dilator response to NTG is due to a VSMC abnormality in migraineurs without aura.

2.2 Biology

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Acknowledgement A machine generated summary based on the work of Fujioka, Kazumi; Oishi, Minoru; Fujioka, Akira; Nakayama, Tomohiro. 2018  in Journal of Medical Ultrasonics.

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