title: Impaired 5-hydroxytryptamine tachyphylaxis in migraine.
abstract: Tachyphylaxis (TPX) to the spasmogenic activity of 5HT can be demonstrated in vivo in the superficial hand dorsal veins in man by the computerized venotest. The 5HT-TPX is reverted by previous local naloxone administration. Tachyphylaxis to 5HT is usually absent in the migraineur. The restored 5HT spasmogenic effect by naloxone suggests the possibility of local opioid apparatus participation in TPX to 5HT.
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006225:Hand / Q000098:blood supply; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000503:physiopathology*; D009270:Naloxone; D011957:Receptors, Opioid / Q000032:analysis; D012701:Serotonin; D012702:Serotonin Antagonists; D013618:Tachyphylaxis; D014661:Vasoconstriction; D014680:Veins / Q000032:analysis / Q000503:physiopathology*
chemical_list: D011957:Receptors, Opioid; D012702:Serotonin Antagonists; D012701:Serotonin; D009270:Naloxone