Presynaptic facilitation by serotonin is caused by
A)increased extracellular concentration of sodium ion.
B)increased extracellular concentration of potassium ion.
C)blockage of calcium channels in the presynaptic membrane.
D)calcium channels in the presynaptic membrane remaining open longer.
E)temporal summation.

Question

Quizplus · Accepted Answer

Serotonin facilitates neurotransmitter release in the presynaptic terminal by causing the calcium channels to remain open for a longer duration, leading to an increased influx of calcium ions into the terminal. This increased calcium ion concentration triggers an increase in the release of neurotransmitter vesicles into the synaptic cleft and facilitates synaptic transmission.

Presynaptic Facilitation by Serotonin Is Caused by