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Pituitary adenylate cyclase activating polypeptide and migraine
Alessandro S Zagami1, Lars Edvinsson2, Peter J Goadsby3
1Institute of Neurological Sciences, Prince of Wales Hospitals and Prince of Wales Clinical School, University of New South Wales Sydney, Australia.
Annals of Clinical and Translational Neurology
|January 10, 2015
Summary
Pituitary adenylate cyclase activating peptide (PACAP) may trigger migraine headaches. Lowering PACAP levels in patients with migraine headaches shows potential for new therapeutic strategies.
Area of Science:
- Neuroscience
- Pharmacology
Background:
- Pituitary adenylate cyclase activating peptide (PACAP) is present in the trigeminocervical complex.
- PACAP has been implicated in the pathophysiology of migraine headaches.
Purpose of the Study:
- To investigate the role of PACAP in migraine pathophysiology.
- To assess PACAP levels in migraine patients and the effect of sumatriptan treatment.
Main Methods:
- Radioimmunoassay was used to measure PACAP levels.
- PACAP was measured in cranial blood of cats following superior sagittal sinus (SSS) stimulation.
- PACAP levels were measured in the external jugular vein of migraine patients during headache, after sumatriptan treatment, and interictally.
Main Results:
- Stimulation of the SSS in cats elevated cranial blood PACAP levels.
- Patients with moderate to severe migraine exhibited elevated PACAP levels during headaches.
- Sumatriptan treatment reduced PACAP levels in migraine patients.
- Interictal PACAP levels were lower than during headache or after treatment.
Conclusions:
- PACAP is a potential trigger for migraine headaches.
- PACAP levels are elevated during migraine attacks and decrease with sumatriptan treatment.
- PACAP and its receptors represent a promising therapeutic target for migraine treatment.
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