Voltage Gated Calcium Channels as Targets for Analgesics

Emmanuel Bourinet; Gerald W. Zamponi

Abstract

Management of pain is an essential aspect of medicine; however, current therapies are frequently insufficient owing to severe side effects or limited effectiveness. Therefore, the discovery of new analgesics is needed, especially to treat the proportion of painful patients poorly improved by available analgesics. The transmission of nociceptive stimuli in primary afferent neurons critically depends on a peculiar repertoire of various types of ion channels such as a number of TRP channels, persistent sodium channels, inwardly rectifying potassium channels and voltage-gated calcium channels that either detect noxious stimuli, or regulate cellular excitability and synaptic transmission. Moreover, some of these channels are redistributed and upregulated in pathological states leading to abnormal detection or transmission of harmful stimuli, and consequently lead to states of chronic pain. Hence, these channels are considered key targets for the development of analgesics. The nervous system expresses multiple types of calcium channels with specialized roles in neurophysiology. Here, we review the role of these channels and their accessory subunits in nociceptive signaling, and their potential as targets for development of innovative analgesics.

Keywords: n-type channel, t-type channel, opioid receptors, nociception, prialt, gabapentin, neurontin, lyrica, nociceptin receptors