ANATOMY

Detailed explanation-1: -The channels are opened, or gated, by the binding of a neurotransmitter to an orthosteric site(s) that triggers a conformational change that results in the conducting state. Modulation of gating can occur by the binding of endogenous, or exogenous, modulators to allosteric sites.

Detailed explanation-2: -When the NMDA receptor is activated by the binding of two co-agonists, the cation channel opens, allowing Na+ and Ca2+ to flow into the cell, in turn raising the cell’s electric potential. Thus, the NMDA receptor is an excitatory receptor.

Detailed explanation-3: -Ligand-gated ion channels are activated upon the binding of a neurotransmitter to the ion channel and are involved in fast synaptic transmisssion in the nervous system.

Detailed explanation-4: -Ligand-gated ion channels open when a chemical ligand such as a neurotransmitter binds to the protein. Voltage channels open and close in response to changes in membrane potential. Mechanically-gated channels open in response to physical deformation of the receptor, as in sensory receptors of touch and pressure.

Detailed explanation-5: -GABA is the major inhibitory neurotransmitter in the brain. GABAA receptors are ligand-gated ion channels, whereas GABAB receptors are G protein-coupled receptors.