Metoclopramide inhibits trigeminovascular activation:evidence for effective acute attack treatment in migraine.

BACKGROUND/AIM: Metoclopramide is an effective and commonly used medication in acute migraine treatment but an experimental evidence base is lacking. We aimed to investigate the antimigraine effect of metoclopramide in a migraine model and whether the analgesic effect of metoclopramide was likely to be D2 receptor-mediated. MATERIALS AND METHODS: Cortical spreading depression (CSD) was used to model migraine in adult male Wistar rats. Five CSDs were induced by pinprick. Metoclopramide (two different doses), raclopride, or 0.9% saline were administered 30 min before CSD induction. Two hours after the experiments, brain tissues were examined for c-fos activation. RESULTS: In metoclopramide groups brain stem c-fos expression was significantly lower than in the CSD side of the saline group (P = 0.002). In the raclopride group, ipsilateral brain stem c-fos expression was also lower than in the saline group (P = 0.002). No difference in c-fos expression in the ipsilateral trigeminal nucleus caudalis between the raclopride and metoclopramide groups was observed (P > 0.05). CONCLUSION: Metoclopramide is shown to suppress trigeminovascular activation for the first time, providing an experimental basis for its role in migraine. The analgesic effect of metoclopramide is likely to be mediated by D2 receptors since raclopride, a selective D2 receptor antagonist, suppresses trigeminovascular activation similarly.

The association between ocular dominance and physiological palpebral fissure asymmetry.

Physiological palpebral fissure asymmetry is a common observation in a physician's everyday practice. The goal of this study was to examine the relationship between palpebral fissure height (PFH) and ocular dominance. Sixty-nine healthy volunteers (42 female, 27 male) were included in this research, and ocular dominance was determined using hole-in-the-card and pointing-a-finger tests. Those volunteers with inconsistent test results were excluded. Standard photographs were taken of all of the subjects in the primary position with a consistent background and photographic equipment. The PFHs were measured using an ImageJ analyser, and a mixed ANOVA was used for the statistical analysis. Overall, 87% of the participants showed small differences in their PFHs, with their dominant eyes being significantly wider than their non-dominant eyes (10.51 ± 0.97 vs. 10.32 ± 1.03; p = .001). This study revealed that ocular dominance has a significant effect on the PFH. Further research is required to understand the importance of this association in daily practice.