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→Postsynaptic Mechanisms of Chemical Transmission
* If the ion channels that are gated by neurotransmitter and begin to conduct after the transmitter has bound them are permeable to ions whose equilibrium or Nernst potentials are more negative than the resting potential, then the cell will almost certainly hyperpolarize, and become less likely to fire an action potential. This is an example of an '''inhibitory postsynaptic potential''', usually abbreviated as '''IPSP'''.
* An important form of inhibition can occur if the transmitter opens channels that increase the permeability of the membrane to ions whose equilibrium or Nernst potential is close to the resting potential, such as chloride ion channels, whose equilibrium potential is often close to or at the neuron's resting potential. Even though the neuron may not hyperpolarize, the synapse increases its the neuron's conductance, and thus reduces its in turn reducing the neuron's response to injected current, and thus reduces its the neuron's excitability. Such inhibition is referred to as '''shunting inhibition''' (since injected current is shunted by the increased conductance) or''' silent inhibition''' (since the membrane potential may not change, even though the neuron is less excitable).
* These excitatory or inhibitory synaptic potentials all result from opening ligand-gated ion channels, which increases the membrane conductance.
