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Current Neurology and Neuroscience Reports

, Volume 8, Issue 4, pp 345–352 | Cite as

New molecular targets for antiepileptic drugs: α2δ, SV2A, and Kv7/KCNQ/M potassium channels

  • Michael A. Rogawski
  • Carl W. Bazil
Article

Abstract

Many currently prescribed antiepileptic drugs (AEDs) act via voltage-gated sodium channels, through effects on γ-aminobutyric acid-mediated inhibition, or via voltage-gated calcium channels. Some newer AEDs do not act via these traditional mechanisms. The molecular targets for several of these nontraditional AEDs have been defined using cellular electrophysiology and molecular approaches. Here, we describe three of these targets: α2δ, auxiliary subunits of voltage-gated calcium channels through which the gabapentinoids gabapentin and pregabalin exert their anticonvulsant and analgesic actions; SV2A, a ubiquitous synaptic vesicle glycoprotein that may prepare vesicles for fusion and serves as the target for levetiracetam and its analog brivaracetam (which is currently in late-stage clinical development); and Kv7/KCNQ/M potassium channels that mediate the M-current, which acts a brake on repetitive firing and burst generation and serves as the target for the investigational AEDs retigabine and ICA-105665. Functionally, all of the new targets modulate neurotransmitter output at synapses, focusing attention on presynaptic terminals as critical sites of action for AEDs.

Keywords

Potassium Channel Gabapentin Pregabalin Levetiracetam Axon Initial Segment 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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© Current Medicine Group LLC 2008

Authors and Affiliations

  1. 1.Department of Neurology, School of MedicineUniversity of California, DavisSacramentoUSA

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