Mulleners W M, Chronicle E P, Vredeveld J W, Koehler P J
Department of Neurology, Atrium Medical Center, Heerlen, The Netherlands.
Eur J Neurol. 2002 Jan;9(1):35-40. doi: 10.1046/j.1468-1331.2002.00334.x.
We examined the effect of standard migraine prophylaxis with sodium valproate on repeated measures of occipital excitability using transcranial magnetic stimulation (TMS). We predicted that, comparing pre- and post-treatment assessments, a reduction in clinical migraine parameters would be paralleled by a decrease in excitability measurements.A total of 31 migraine patients enrolled in the study, for assessment prior to and 1 month after commencement of sodium valproate prophylaxis. At each assessment, we used a standardized protocol to stimulate the occipital cortex with a 90-mm circular (coil A) and 70 mm figure-of-eight (coil B) coil. We recorded the threshold stimulation intensity at which subjects just perceived phosphenes. Subjects kept detailed records of headache parameters 1 month before and also during the study period. Valproate therapy significantly improved headache indexes, as expected. In MA subjects assessed with coil B, phosphene thresholds were significantly higher post-treatment than pre-treatment, but those for MO did not change. Modest correlations were observed in MA patients between increase in phosphene threshold and decrease in headache index. Although preliminary, the findings with coil B lend some support to the notion that effective migraine prophylaxis may be achieved through lowering cortical excitability by gamma-aminobutyric acid (GABA)-ergic intervention. Further investigation of the effect of sodium valproate or other similarly acting substances on cortical excitability in migraine is warranted.
我们使用经颅磁刺激（TMS）研究了丙戊酸钠标准偏头痛预防性治疗对枕叶兴奋性重复测量的影响。我们预测，比较治疗前后的评估，临床偏头痛参数的降低将与兴奋性测量值的降低同时出现。共有31名偏头痛患者参与了该研究，在丙戊酸钠预防性治疗开始前及开始后1个月进行评估。每次评估时，我们使用标准化方案，用90毫米圆形（线圈A）和70毫米8字形（线圈B）线圈刺激枕叶皮质。我们记录了受试者刚刚感知到光幻视的阈值刺激强度。受试者详细记录了研究前1个月以及研究期间的头痛参数。正如预期的那样，丙戊酸治疗显著改善了头痛指数。在用线圈B评估的偏头痛伴无先兆（MA）受试者中，治疗后光幻视阈值显著高于治疗前，但偏头痛伴先兆（MO）受试者的光幻视阈值没有变化。在MA患者中，观察到光幻视阈值增加与头痛指数降低之间存在适度的相关性。尽管是初步的，但线圈B的研究结果为以下观点提供了一些支持，即通过γ-氨基丁酸（GABA）能干预降低皮质兴奋性可能实现有效的偏头痛预防性治疗。有必要进一步研究丙戊酸钠或其他类似作用物质对偏头痛患者皮质兴奋性的影响。
