botulinum toxin type a therapy in migraine: preclinical and clinical trials

conclusions the evidence that btx-a decreases ntg-induced cgrp-li and sp-li levels in trigeminovascular system suggests that btx-a attenuates migraine by suppression of neuropeptide release. btx-a injections for migraine at acupoint-sites and fixed-sites are effective. acupoint-sites btx-a administration shows more efficacy for migraine than fixed-sites application. results local btx-a injection suppressed ntg-induced cgrp-li and sp-li levels in jugular plasma and oblongata. btx-a injection for both groups with migraine significantly reduced the attack frequency, intensity, duration and associated symptoms. the efficacy of btx-a for migraine in group a (93% improvement) was more significant than that in group f (83% improvement) (p < 0.01). materials and methods rats with ntg-induced migraine were subcutaneously injected with vehicle or btx-a (5 u/kg or 10 u/kg bodyweight). cgrp- and sp-like immunoreactivity (cgrp-li and sp-li) were determined by radioimmunoassay. in clinical trials, sixty patients respectively received btx-a (2.5 u each site, 25 u per patient) at fixed-sites (group f, n = 30) including occipitofrontalis, corrugator supercili, temporalis and trapezius or at acupoint-sites (group a, n = 30) including ex-hn3, ex-hn5, gv20, gb8, gb20 and bl10. background botulinum toxin type a (btx-a) has been reported to be effective for the therapy for migraine. the purpose of this study was to investigate the effect of btx-a on the immunoreactive levels of calcitonin gene-related peptide (cgrp) and substance p (sp) in the jugular plasma and medulla oblongata of migraine in rats induced by nitroglycerin (ntg), and then to evaluate and compare the effectiveness of fixed (muscle)-sites and acupoint-sites injection of btx-a for migraine therapy of patients in a randomly controlled trial extending over four months.