Monoamine sensitivity of smooth muscle in vivo in nociception disorders.
A significant degree of supersensitivity to 5-HT and DA was detected when carrying out the computerized venotest on migraine patients during an attack. A similar supersensitivity was observed during morphine abstinence and naloxone-precipitated withdrawal in addicts. Mild abstinence after slight and short morphine treatment provoked monoamine supersensitivity in volunteers. In these conditions, the administration of morphine inhibited the 5-HT and DA supersensitivity. In spontaneous central panalgesia, monoamine supersensitivity is detectable, as well as in panalgesia induced in headache sufferers by means of PCPA 5-HT deprivation. By means of the venotest, the ergot derivatives were confirmed as being partial 5-HT agonists. These drugs can also carry out their therapeutic activity by potentiating 5-HT at a central level in 5-HT-deficient neurons. The presence of opiate receptors in the human vein is stressed. The high supersensitivity of the venous smooth muscle to 5-HT and DA both in headache and systemic pain sufferers and during morphine withdrawal suggests a pathophysiological analogy between these conditions.
D004298:Dopamine; D004723:Endorphins / Q000502:physiology; D004879:Ergotamines / Q000494:pharmacology; D006556:Heroin Dependence; D006801:Humans; D008881:Migraine Disorders / Q000175:diagnosis* / Q000503:physiopathology; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009469:Neuromuscular Junction / Q000187:drug effects; D009619:Nociceptors / Q000187:drug effects; D011957:Receptors, Opioid / Q000502:physiology; D012701:Serotonin; D012702:Serotonin Antagonists; D013375:Substance Withdrawal Syndrome / Q000503:physiopathology; D014680:Veins / Q000187:drug effects
D004723:Endorphins; D004879:Ergotamines; D011957:Receptors, Opioid; D012702:Serotonin Antagonists; D012701:Serotonin; D004298:Dopamine