Associations between cerebral and systemic endothelial function in migraine patients: a post-hoc study.

BACKGROUND: There is a growing interest in the role of the endothelium in migraine. Recently, our group showed differences in endothelial function between the anterior and posterior cerebral circulation in healthy subjects, reduced vasodilatatory capacity of the posterior cerebral circulation and unimpaired systemic endothelial function in migraine patients without comorbidities. However, the relationship between cerebral and systemic endothelial function and the anterior and posterior cerebral endothelial function in migraine patients is still not clear. METHODS: We compared cerebral and systemic endothelial function through post-hoc linear regression analysis of cerebrovascular reactivity (CVR) to L-arginine between the middle cerebral artery (MCA) and flow-mediated vasodilatation (FMD) of the right brachial artery and the posterior cerebral artery (PCA) and FMD in migraine patients without comorbidities and in healthy subjects. The anterior and posterior cerebral endothelial function was also compared using post-hoc linear regression analysis between CVR to L-arginine in the MCA and the PCA. RESULTS: No significant correlation was found between CVR to L-arginine in the MCA and FMD and in the PCA and FMD in migraine patients with aura (p = 0.880 vs. p = 0.682), without aura (p = 0.153 vs. p = 0.179) and in healthy subjects (p = 0.869 vs. p = 0.662). On the other hand, we found a significant correlation between CVR to L-arginine in the MCA and PCA in migraine patients with aura (p = 0.004), without aura (p = 0.001) and in healthy subjects (p = 0.002). Detailed analysis of the linear regression between all migraine patients and healthy subjects did not show any difference in the regression coefficient (slope) (p = 0.382). However, a significant difference in curve elevation (intercept) was found (p = 0.002). CONCLUSIONS: Our study suggests that the endothelial function in the cerebral and systemic circulation might be different in migraine patients without comorbidities, while that of the anterior and posterior cerebral circulation might be coupled. These results could improve understanding of endothelial function in migraine patients without comorbidities.

Endothelium-dependent vasodilatation in migraine patients.

BACKGROUND: Endothelial dysfunction could be involved in the pathophysiology of migraine. The results obtained from a few studies on endothelial dysfunction in migraine are controversial. We investigated brachial flow-mediated dilatation (FMD), which reflects systemic endothelial dysfunction, in migraine patients without comorbidities. By employing strict inclusion criteria we avoided the possible changes to FMD from confounding factors. METHODS: Forty migraine patients without comorbidities (20 with and 20 without aura) and 20 healthy subjects were included. FMD of brachial arteries and carotid intima-media thickness were measured by using standard procedures. RESULTS: We did not find any difference in FMD between migraine patients and healthy subjects (p = .96). Also, no differences were found among healthy subjects, migraine patients with aura and without aura (p = .99). CONCLUSION: Our study showed that systemic endothelial function is not impaired in migraine patients without comorbidities, neither in those with or without aura. Considering these findings, the investigation of cerebral endothelial function would be useful in a further investigation of the role of endothelial (dys)function in migraine pathophysiology.

Differences between cerebrovascular reactivity to L-arginine in the anterior and posterior cerebral circulation.

BACKGROUND: Cerebral endothelial function might be different in distinct cerebrovascular territory, thereby making these areas more susceptible to ischemia and stroke. Higher incidence and prevalence of stroke in males suggest that gender could have a strong influence on this difference. In order to evaluate cerebral endothelial function, we compared cerebrovascular reactivity (CVR) to L-arginine in the anterior and posterior cerebral circulation in healthy young males and females. METHODS: Thirty healthy subjects, 15 females (32.1 ± 7.1 years) and 15 males (32.2 ± 6.3 years), were included. The mean arterial velocity in the middle cerebral artery (MCA) and the posterior cerebral artery (PCA) was measured by transcranial Doppler sonography before and after intravenous infusion of L-arginine, and CVR to L-arginine was then calculated. RESULTS: CVR to L-arginine was significantly higher in PCA than in MCA in all subjects (19.2 ± 8.2 vs. 13.6 ± 7.1%, p ≤ 0.01). In addition, CVR to L-arginine was significantly more pronounced in females compared to males in PCA (22.7 ± 8.3 vs. 15.8 ± 6.7%, p ≤ 0.01) and MCA (16.8 ± 6.4 vs. 10.4 ± 6.4%, p < 0.05). CONCLUSIONS: Lower CVR to L-arginine and therefore lower cerebral endothelial function in the anterior cerebral circulation and in males might be related to the higher incidence of ischemia and stroke in the anterior cerebral circulation, particularly in males.