For presynaptic inhibition, I am aware of these:
Ca²+ influx (into the presynaptic nerve terminal) is decreased. And this in turn reduces the probability of releasing synaptic vesicles from the presynaptic neuron.
The influx of Ca²+ is under the influence of voltage-gated Ca²+ channels.
What inhibitor(s) can be involved in this inhibition?
What is the ionic basis of this inhibition? (By this, I want to know how the movement of ions affects the voltage-gated Ca²+ channels)
Does the reaction cascade intitiated by the inhibitor in any way affect the amplitude of the AP generated upstream when it reaches the presynaptic nerve terminal?