Platelet P1, P4-Di (adenosine-51) tetraphosphate (AP4A) in migraine patients before and during beta-adrenoceptor blockade
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Published on: June 2, 2014
K Winther1, C Hedman, H Flodgaard
1Department of Clinical Chemistry, Frederiksberg and Hvidovre Hospital, Copenhagen, Denmark.
Abstract:
P1,P4-Di(adenosine-51) tetraphosphate (AP4A) is a metabolically inactive nucleotide which can be released from platelet dense granules. This study was designed firstly, to investigate whether platelet content of AP4A was decreased in patients with classical migraine and secondly, whether the content of AP4A was changed by beta-adrenoceptor blockade. No significant difference in platelet dense granule content of AP4A, was observed between 10 migraine patients and 10 normal controls. Both metoprolol, a beta 1-selective blocker and propranolol, a non-selective beta-blocker significantly decreased the migraine attack rate. However, while propranolol significantly reduced the platelet content of AP4A, metoprolol did not. Therefore, the present data suggest that platelet dense granule release, as estimated by the content of AP4A is not of major importance in migraine.
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