[The mechanism of peripheral and central sensitization in migraine. A literature review].
Migraine attacks are characterized by unilateral throbbing, pulsating headache associated with nausea, vomiting, photophobia, phonophobia and allodynia. Peripheral sensitization is an acute, chemical-induced form of functional plasticity, which converts high-threshold nociceptors into low-threshold sensory neurons. This form of sensitization occurs when the nerve terminals (meningeal nociceptors) of the neurons of the trigeminal ganglion are soaked with the "inflammatory" soup (prostaglandin E2, bradykinin, serotonin and cytokines) along the vasculature of the cerebral dura mater. Peripheral sensitization in migraine attacks is explained clinically by intracranial hypersensitivity (the headache worsens during coughing or physical activity) and by a throbbing element in the pain of migraine (sensitized nociceptors become hyperresponsive to the otherwise innocuous and unperceived rhythmic fluctuation in intracranial pressure produced by normal arterial pulsation). The essence of central sensitization is that the second-order neurons in the trigeminocervical complex become hyperexcitable. The altered behavior of the second-order neurons is based on the increased glutamate sensistivity of the NMDA receptors and the neuronal nitric oxide synthase activity stimulated by nitric oxide. This process is explained clinically by face and scalp ollodynia and by neck stiffness (extracranial tenderness).
Tajti
János
J
Szegedi Tudományegyetem Neurológiai Klinika, Szeged. tajti@nepsy.szote.u-szeged.hu
Vécsei
László
L
D001920:Bradykinin / Q000378:metabolism; D016207:Cytokines / Q000378:metabolism; D015232:Dinoprostone / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D007427:Intracranial Pressure; D008578:Meninges / Q000503:physiopathology*; D008881:Migraine Disorders / Q000378:metabolism / Q000503:physiopathology*; D020325:Migraine with Aura / Q000503:physiopathology; D020326:Migraine without Aura / Q000503:physiopathology; D009473:Neuronal Plasticity; D009569:Nitric Oxide / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I / Q000378:metabolism; D009619:Nociceptors / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism; D012668:Trigeminal Ganglion / Q000503:physiopathology*
D016207:Cytokines; D018836:Inflammation Mediators; D016194:Receptors, N-Methyl-D-Aspartate; D009569:Nitric Oxide; D012701:Serotonin; D018698:Glutamic Acid; D052248:Nitric Oxide Synthase Type I; D015232:Dinoprostone; D001920:Bradykinin