Decentralization monoamine super-sensitivity of migraine and opiate abstinence: common features and different target mechanisms?

The similarity between opiate withdrawal and migraine (M) has been confirmed regarding increased monoamine sensitivity at the neuromuscular junction of the hand's dorsal vein as well as at the neuraxis where dopamine (DA) supersensitivity was observed. Similarities also included an increase in cAMP levels as a precocious sign in both M and opiate withdrawal. Particular attention has been devoted to the time-course of monoamine supersensitivity in M and in abstinence. It has been found that the maximum level of super-sensitivity occurs in M at the end of the M attack, whereas the maximum super-sensitivity is present at the very beginning of opiate abstinence. The inverse time-course of this phenomenon suggests that it could play some pathophysiological role in inducing the end of the M attack. Conversely, it can represent the expected transient result of a pharmacological denervation which ought to result in a supersensitivity of opioid-dependent neuron during withdrawal. In M, the super-sensitivity is wider, indeed, it involves more receptor types. This could be an indirect proof of the involvement of inhibitory pathways other than the opioidergic one.