Regulation of two-pore-domain potassium TREK channels and their involvement in pain perception and migraine.

The ability to sense pain signals is closely linked to the activity of ion channels expressed in nociceptors, the first neurons that transduce noxious stimuli into pain. Among these ion channels, TREK1, TREK2 and TRAAK from the TREK subfamily of the Two-Pore-Domain potassium (K2P) channels, are hyperpolarizing channels that render neurons hypoexcitable. They are regulated by diverse physical and chemical stimuli as well as neurotransmitters through G-protein coupled receptor activation. Here, we review the molecular mechanisms underlying these regulations and their functional relevance in pain and migraine induction.

Migraine and Two-Pore-Domain Potassium Channels.

Migraine is a common, disabling neurological disorder with a genetic, environmental, and hormonal component with an annual prevalence estimated at ~15%. It is characterized by attacks of severe, usually unilateral and throbbing headache, and can be accompanied by nausea, vomiting, and photophobia. Migraine is clinically divided into two main subtypes: migraine with aura, when it is preceded by transient neurological disturbances due to cortical spreading depression (CSD), and migraine without aura. Activation and sensitization of trigeminal sensory neurons, leading to the release of pro-inflammatory peptides, is likely a key component in headache pain initiation and transmission in migraine. In the present review, we will focus on the function of two-pore-domain potassium (K2P) channels, which control trigeminal sensory neuron excitability and their potential interest for developing new drugs to treat migraine.