1. Cell to Cell Communication via Ion-Channel Linked Receptors
Thursday, January 17, 2019
Cell to Cell Communication via Ion-Channel Linked Receptors
Packet #18
Chapter #11

2. Ion-Channel-Linked Receptors
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Also known as transmitter-gated ion channels
Found in muscle and nervous tissue
Convert chemical signals into electrical signals
Receptors serve for rapid transmission across synapses in the nervous system
Chemical signal arrives as a neurotransmitter
Delivered to the outside of the target cell
Chemical signal changes to an electrical signal in the form of a change in voltage across the plasma membrane

3. Ion-Channel-Linked Receptors II
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Neurotransmitter binds
Receptor alters its conformation
Causes channel to open (or close)
Allows the flow of specific ions across membrane
Na+ K+
Ca2+
Cl-
Driven by electrochemical gradient, ions rush in or out of the cell
Depends on the concentration gradient
Results in a change in the membrane potential of the post-synaptic cell
Change promotes, or inhibits, neurotransmission

4. Ion-Channel-Linked Receptors III
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Examples of Neurotransmitters
Nicotinic acetylcholine
Nerve and muscle
GABA
Γ-aminobutyric acid
CNS
Glycine
Special Note
Many ion channels are not directly coupled to their receptors but are coupled by G-proteins

5. Ion Channel Receptors
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