miniature end-plate potential
Quick Summary
A miniature end-plate potential (MEPP) is a small, chemically induced change in the electrical potential of the motor end plate, which is part of the muscle cell membrane opposite a nerve fiber terminal at the neuromuscular junction. This occurs when a nerve impulse releases the neurotransmitter acetylcholine from the nerve terminal. Acetylcholine binds to receptors on the end plate, opening channels that allow sodium ions to flow into the muscle cell, causing a slight depolarization.1
An enzyme then breaks down the acetylcholine, closing the channels and allowing the membrane to return to its polarized state. A single burst of acetylcholine, called a quantum, causes one MEPP. Multiple MEPPs, released by a nerve impulse, can summate to create a larger end-plate potential (EPP), which can trigger an action potential and muscle contraction.1
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- end-plate potential
…a slight depolarization, called a miniature end-plate potential (MEPP). One hundred to 200 quanta, released simultaneously or in rapid series by a nerve impulse, cause multiple MEPPs, which summate, or combine, to produce an EPP. If the EPP depolarizes the cell to a crucial threshold level, it will fully activate…
Read More…a slight depolarization, called a miniature end-plate potential (MEPP). One hundred to 200 quanta, released simultaneously or in rapid series by a nerve impulse, cause multiple MEPPs, which summate, or combine, to produce an EPP. If the EPP depolarizes the cell to a crucial threshold level, it will fully activate…
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nervous systemPostsynaptic potentialThese tiny electrical events, called miniature end-plate potentials (MEPPs), or miniature postsynaptic potentials (MPSPs), are caused by the random release of single quanta of neurotransmitter from a resting presynaptic terminal. The EPP is actually made up of multiple MEPPs, which arise when an activated terminal releases hundreds of neurotransmitter quanta.…
Read MoreThese tiny electrical events, called miniature end-plate potentials (MEPPs), or miniature postsynaptic potentials (MPSPs), are caused by the random release of single quanta of neurotransmitter from a resting presynaptic terminal. The EPP is actually made up of multiple MEPPs, which arise when an activated terminal releases hundreds of neurotransmitter quanta.…
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