Migraine and the Mu-Opioidergic System – Can We Directly Modulate it? Evidence from Neuroimaging studies

摘要

Migraine is a chronic trigeminal pain condition that affects the existence of great part of our population. Its debilitating headache attacks, with increased sensitivity to multiple forms of stimuli, force many of the patients to frequently rely upon over the counter analgesics, and quite frequently resort to abuse of prescribed medications, particularly the opioid agonists. In the latter case, the indiscriminate medication-driven activation of the opioid system can lead to undesired side effects, such as the augmentation of hyperalgesia and allodynia, as well as the chronification of the attacks. However, we still lack information regarding the impact of migraine attacks, and its relief on the function of μ-opioid receptor (μOR) mediated neurotransmission, the primary target of opioid medications. This line of enquiry is of particular importance as this neurotransmitter system is arguably the endogenous brain mechanism most centrally involved in pain regulation, as well as the effectiveness of opioid medications. Recently, new advances in molecular neuroimaging and neuromodulation have provided important information that can elucidate, in vivo, the role of the endogenous opioid system in migraine suffering and relief.