Increased Brainstem Serotonergic Transporter Availability in Adult Migraineurs: an [F-18]FP-CIT PET Imaging Pilot Study

Abstract

Purpose Recent studies have proposed central serotonergic dysfunction as a major pathophysiology of migraine. We investigated serotonin transporter (SERT) availability in migraineurs using F-18-N-(3-fluoropropyl)-2 eta-carbomethoxy-3 beta-(4-iodophenyl) nortropane ([F-18]FP-CIT) positron emission tomography (PET). Methods Brain [F-18]FP-CIT PET images were obtained in eight women with migraine during headache free phase and 12 healthy adult women, 120 min after injection of 185 MBq. Non-displaceable binding potential (BPND) of [F-18]FP-CIT, which is an estimate of SERT availability, was calculated at the brainstem and compared with clinical parameters. Results BPND at the brainstem was significantly higher in adult migraineurs (n=6, 1.15 +/- 0.17) than healthy subjects (0.95 +/- 0.14) (p=0.04). Healthy subjects demonstrated negative correlation between brainstem BPND and age (r=-0.64, p=0.02), whereas this age-related decline pattern was not found in the migraineurs. Severity of migraine attack was significantly correlated with brainstem BPND (r=0.66, p=0.02), when age and duration of illness were corrected. Conclusions Increased SERT availability in the brainstem of adult migraineurs indicates low serotonin neurotransmission during headache-free phase. Patients who experience more painful headaches have lower serotonin neurotransmission. [F-18]FP-CIT PET is a useful in vivo imaging technique for evaluating brainstem SERT availability in migraineurs.