Drug targets: ligand and voltage gated ion channels

Nilan T. Jacob


The elucidation of a drug target is one of the earliest and most important steps in the drug discovery process. Ion channels encompassing both the ligand gated and voltage gated types are the second most common drug targets after G-Protein Coupled Receptors (GPCR). Ion channels are basically pore forming membrane proteins specialized for conductance of ions as per the concentration gradient. They are further broadly classified based on the energy (ATP) dependence into active ion channels/pumps and passive ion channels. Gating is the regulatory mechanism of these ion channels by which binding of a specific molecule or alteration in membrane potential induces conformational change in the channel architecture to result in ion flow or its inhibition. Thus, the study of ligand and voltage gated ion channels becomes an important tool for drug discovery especially during the initial stage of target identification. This review aims to describe the ligand and voltage gated ion channels along with discussion on its subfamilies, channel architecture and key pharmacological modulators.


Drug targets, Ion channels, Ligand gated ion channels, Receptor pharmacology, Voltage gated ion channels

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