Post-tetanic potentiation (PTP) is a form of
synaptic plasticity
In neuroscience, synaptic plasticity is the ability of synapses to strengthen or weaken over time, in response to increases or decreases in their activity. Since memories are postulated to be represented by vastly interconnected neural circuits ...
which is short-lived and results in increased frequency of
miniature excitatory postsynaptic potentials (mEPSPs) or currents (EPSCs) with no effect on amplitude in the spontaneous
postsynaptic potential
Postsynaptic potentials are changes in the membrane potential of the postsynaptic terminal of a chemical synapse. Postsynaptic potentials are graded potentials, and should not be confused with action potentials although their function is to ini ...
. It usually lasts in the range of several minutes (shorter potentiations are usually referred to as 'augmentations'). PTPs are observed when synapses are stimulated with repetitive (tetanic) pulses, by means of prolonged trains of stimuli applied at high frequencies (10 Hz to 200 Hz stimuli applied for .2 seconds to 5 seconds).
PTPs are thought to result primarily from the buildup of calcium concentration in the axon terminal of the presynaptic neuron during the stimulus train.
However, this is a topic under debate
as changes that last this long outlive the rate at which calcium is transported out of the presynaptic neuron.
In some cases, depression can be observed instead of potentiation following the tetanic stimulus.
See also
*
Long-term potentiation
In neuroscience, long-term potentiation (LTP) is a persistent strengthening of synapses based on recent patterns of activity. These are patterns of synaptic activity that produce a long-lasting increase in signal transmission between two neurons ...
References
Neuroplasticity
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