Difference between Ligand Gated Ion Channel and Voltage Gated Ion Channel (LGIC and VGIC)

7 Differences between Ligand Gated Ion Channel (LGIC) and Voltage Gated Ion Channels (VGIC)

Cell membranes are generally impermeable to ions; thus, they must diffuse through the membrane through transmembrane protein channels or ion channels.

Ion channel receptors are pore-forming transmembrane protein complexes that allow ions to pass through it upon ligand binding or voltage difference. Ion channel proteins are transmembrane integral proteins that allows flow of ions.

Ion channels are classified on the basis of gating or type of stimuli responsible for its opening and closing

1. Ligand gated ion channels (ionotropic receptors)
2. Voltage gated ion channels

Video on Difference between Ligand Gated and Voltage gated Ion channels

Ligand Gated Ion Channels (LGIC)	Voltage Gated Ion Channels (VGIC)
Allow ions to flow into or out of the cell in response to the binding of a ligands like neurotransmitter	Allow ions to flow in or out of the cell in response in response to changes in membrane potential
Binding of ligand causes a conformational change causing opening of the ion channel that allows flow of ions	Change in membrane potential causes a conformational change; thereby regulating opening and closing of the channel
The receptor has an extracellular domain for ligand binding and transmembrane domain with an ion pore or ion channel	The receptor has a voltage-sensing domains to sense changes in membrane potential and transmembrane domain with an ion pore or ion channel
Not specific to a specific ion	Ion specific
LGIC Involved in fast synaptic transmission in the nervous system critical for mediating cell-cell communication and cellular excitability in neurons and cardiomyocytes.	VGICs involved in many electrically mediated cellular functions, including neuronal signaling, muscle cell contraction, cell secretion, hormone regulation, etc.
Examples: Acetylcholine Receptors, Glutamate receptor, Glycine receptor, GABA receptor	Sodium (Na+) Channel, Potassium (K+) channel, Calcium (Ca2+) channel etc
LGIC targeted drugs: Benzodiazepines, Phencyclidine	Calcium channel targeted drugs amlodipine, felodipine, Sodium channel blocking agents dronedarone and amiodarone