Platelet nitric oxide metabolites in migraine

Nitric oxide (NO) is a candidate as a causative molecule in migraine. We de termined nitrite, total nitrate/nitrite, and cyclic guanosine 3',5'-monopho sphate (cGMP) concentrations in platelets from 30 migraine without aura (Mw oA) patients and 17 migraine with aura (MwA) patients. All migraine patient s were studied during their migraine attacks. The control group consisted o f 28 healthy volunteers. Concentrations of platelet nitrite and total nitra te/nitrite were determined using simple and sensitive nitrate/nitrite fluor ometric assay techniques. High concentrations of platelet nitrite and total nitrate/nitrite were found in patients with MwoA and MwA when compared wit h healthy controls. High concentrations of platelet cGMP were also found in patients with MwoA and MwA. The levels of platelet total nitrate/nitrite s ignificantly decreased in headache-free periods after treatment with oral p ropranolol. These findings suggest that NO is produced in platelets during migraine attacks. It may also be related to the migrainous pain and the cha nges in cerebral blood flow experienced during migraine attacks. These data may provide new strategies for the treatment of migraine. square cGMP, mig raine, nitric oxide, nitrate, nitrile, platelet.