Endogenous Opioids in Cerebrospinal Fluid and Blood in Idiopathic Headache Sufferers

Abstract

SYNOPSIS Endogenous opioids and 5‐hydroxytryptamine are the main neurotransmitters that regulate nociception, hedonia and autonomia. These functions are simultaneously impaired in idiopathic headaches. Enkephalins, beta‐endorphin, and tryptophan (5‐HT precursor) were evaluated in CSF and plasma of migraine and cluster headache sufferers. The following results were obtained:(a) decreased levels of CSF enkephalins in migraine attack and cluster headache,(b) increased CSF Tryptophan (TP) in migraine,(c) increased free plasma TP in migraine attack,(d) increased serum beta‐endorphin‐like‐immunore‐activity at the end of attack.A possible link between these findings and the impairment of nociception, hedonia and vegetative balance in headache sufferers is here discussed.