Effect of naftidrofuryl on platelet-induced vasospasm in vitro. Role of antiserotonergic actions.

This study was designed to analyse the spasmolytic actions of naftidrofuryl (Dusodril, CAS 31329-57-4) more in detail, using isolated vessel segments of bovine coronary arteries (BCA). In this preparation, naftidrofuryl caused a dose-dependent inhibition of 5-HT, U 46.619 ((5Z, 9a, 11a, 13E, 15S)-11,9-(epoxymethano) prosta-5,13-dienoic acid), PGF2 alpha and KCl-induced contractions. Additionally, the actions of naftidrofuryl on platelet-induced vasospasm were investigated using arachidonic acid (AA)-stimulated platelets and BCA. Naftidrofuryl antagonized the vasocontractile effects of secreted 5-HT, but was only slightly active in reducing the TXA2-dependent vessel contraction. The suppression of ADP-induced platelet aggregation and secretion required more than 300 mumol/l naftidrofuryl. These data support the concept of a spasmolytic activity of naftidrofuryl which also involves the antagonism of platelet-derived vasocontractile mediators.