Hypernociceptive syndromes and pharmacological inhibition of endogenous opioid degradation.

Endogenous opioid peptides, by modulating the release of sympathetic transmitters, may play a role in the pathogenesis of migraine and related headaches which are considered hypernociceptive syndromes. Hypoendorphinaemia has been demonstrated in migraine attack. Captopril, a drug able to potentiate morphine analgesia in rats and inhibit enkephalinase in animals and in man, improves the clinical course of migraine. In the present research the cerebrospinal fluid and plasma beta-endorphin (beta-EP) levels have been evaluated following a single oral dose of captopril. The drug increased plasma beta-EP levels in migraine sufferers, and these data may be relevant in the mechanism of action of this drug in migraine and related headaches.