Fanciullacci M, Franchi G, Galli P
Minerva Med. 1976 Jun 2;67(28):1834-9.
By testing venomotor receptors (venous-constriction test), it was possible to show a potentiation of the venous constriction effect of serotonin by methysergide and ergotamine. This 5-HT potentiation was observed only when these drugs were sampled in concentrations similar to those in therapeutic use. When ergotamine and methysergide are sampled in concentrations higher than those used in clinical practice, the expected 5-HT antagonist effect is clearly evident. We could therefore conclude that methysergide and ergotamine can be considered pro-serotonin and not anti-serotonin drugs. The pro-serotonin effect of methysergide and ergotamine might take place peripherally on vasomotor or sensitive receptors and/or at a CNS level, making up for the lack of serotonin which, according to the central theory of essential headache, provokes the painful cephalic syndrome.
通过检测血管运动受体（静脉收缩试验），发现甲基麦角新碱和麦角胺可增强血清素的静脉收缩作用。仅当这些药物的采样浓度与治疗使用浓度相似时，才观察到这种5-羟色胺增强作用。当麦角胺和甲基麦角新碱的采样浓度高于临床实践中使用的浓度时，预期的5-羟色胺拮抗剂作用就会明显显现。因此，我们可以得出结论，甲基麦角新碱和麦角胺可被视为促血清素药物而非抗血清素药物。甲基麦角新碱和麦角胺的促血清素作用可能发生在血管运动或敏感受体的外周和/或中枢神经系统水平，弥补了血清素的不足，根据原发性头痛的中枢理论，血清素的缺乏会引发疼痛性头痛综合征。
