Slow afterhyperpolarisation (sAHP) refers to prolonged periods of hyperpolarisation in a

neuron A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. N ...

cardiomyocyte Cardiac muscle (also called heart muscle, myocardium, cardiomyocytes and cardiac myocytes) is one of three types of vertebrate muscle tissues, with the other two being skeletal muscle and smooth muscle. It is an involuntary, striated muscle that ...

following an

action potential An action potential occurs when the membrane potential of a specific cell location rapidly rises and falls. This depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of animal cells, ...

or other depolarising event. In neurons, trains of action potentials may be required to induce sAHPs; this is unlike fast AHPs that require no more than a single action potential. A variety of ionic mechanism may contribute to sAHPs, including potassium efflux from calcium- or sodium- activated potassium channels, and/or the electrogenic response of the sodium-potassium ATPase.A.T. Gulledge, S. Dasari, K. Onoue, E.K. Stephens, J.M. Hasse, and D. Avesar, A sodium-pump-mediated afterhyperpolarization in pyramidal neurons., Journal of Neuroscience 33:13025-13041 (2013). Depending on neuron type and stimulus used for induction, slow afterhyperpolarisations can last for one second to several tens of seconds, during which time the sAHP effectively inhibits neural activity. Fast and Medium AHPs have shorter durations and different ionic mechanisms.

References

Neurophysiology Biophysics Electrophysiology {{biophysics-stub

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References