Arulmani U, Heiligers J P C, Garrelds I M, Sánchez-López A, Willems E W, Villalón C M, Saxena P R
Department of Pharmacology, Cardiovascular Research Institute 'COEUR', Erasmus MC, University Medical Centre Rotterdam, Rotterdam, the Netherlands.
Cephalalgia. 2004 Sep;24(9):717-27. doi: 10.1111/j.1468-2982.2004.00743.x.
It is suggested that during a migraine attack capsaicin-sensitive trigeminal sensory nerves release calcitonin gene related peptide (CGRP), resulting in cranial vasodilatation and central nociception. Hence, inhibition of trigeminal CGRP release may prevent the above vasodilatation and, accordingly, abort migraine headache. Therefore, this study investigated the effects of sumatriptan (100 and 300 microg/kg, i.v.) on capsaicin-induced carotid haemodynamic changes and on CGRP release. Intracarotid (i.c.) infusions of capsaicin (10 microg/kg/min, i.c.) increased total carotid, arteriovenous anastomotic and capillary conductances as well as carotid pulsations, but decreased the difference between arterial and jugular venous oxygen saturations. Except for some attenuation of arteriovenous anastomotic changes, the capsaicin-induced responses were not affected by sumatriptan. Moreover, i.c. infusions of capsaicin (0.3, 1, 3 and 10 microg/kg/min, i.c.) dose-dependently increased the jugular venous plasma concentrations of CGRP, which also remained unaffected by sumatriptan. The above results support the contention that the therapeutic action of sumatriptan is mainly due to cranial vasoconstriction rather than trigeminal (CGRP release) inhibition.
有人提出，在偏头痛发作期间，对辣椒素敏感的三叉神经感觉神经会释放降钙素基因相关肽（CGRP），导致颅血管扩张和中枢性伤害感受。因此，抑制三叉神经CGRP的释放可能会阻止上述血管扩张，从而终止偏头痛发作。因此，本研究调查了舒马曲坦（100和300微克/千克，静脉注射）对辣椒素诱导的颈动脉血流动力学变化和CGRP释放的影响。颈动脉内（i.c.）输注辣椒素（10微克/千克/分钟，i.c.）可增加总颈动脉、动静脉吻合支和毛细血管的电导以及颈动脉搏动，但会降低动脉血氧饱和度和颈静脉血氧饱和度之间的差异。除了动静脉吻合支变化有所减轻外，辣椒素诱导的反应不受舒马曲坦的影响。此外，颈动脉内输注辣椒素（0. —— 原文此处似乎有误，可能漏了一个数字，推测应该是0.3、1、3和10微克/千克/分钟，i.c.）剂量依赖性地增加颈静脉血浆中CGRP的浓度，这也不受舒马曲坦的影响。上述结果支持这样的观点，即舒马曲坦的治疗作用主要是由于颅血管收缩，而不是抑制三叉神经（CGRP释放）。
