Release of calcitonin gene-related peptide (CGRP) from guinea pig dura mater in vitro is inhibited by sumatriptan but unaffected by nitric oxide


A. J. Hansen MD, DSc, Department of General Pharmacology, Novo Nordisk A/S, Novo Nordisk Park, DK-2760 Maaloev, Denmark. Tel. 45 4443 4775, fax 45 4443 4596, e-mail Received 13 April 2000, accepted 9 November 2000


Migraine attacks can be provoked by administration of nitroglycerin, suggesting a role for nitric oxide (NO). The fact that release of the neuropeptide CGRP from trigeminal sensory nerves occurs during the pain phase of migraine and that NO can augment transmitter release prompted us to study CGRP release from the in situ dura mater in guinea pig skulls. Release of CGRP by capsaicin or by high potassium concentration was concentration-dependent and counteracted in calcium-free medium. The anti-migraine compound, sumatriptan, inhibited CGRP release via the 5-HT1-receptor. The NO donors, nitroglycerin, sodium nitroprusside and S-nitroso-N-acetylpenicillamine did not influence CGRP release, alone or together with the stimulants. We concluded that the skull preparation is well suited for scrutinizing CGRP release from dura mater. The fact that sumatriptan inhibits CGRP release as in migraine patients suggests a use for the present preparation in headache research.