Presynaptic Release of NT Flashcards
What do connexins do?
Form current passing pores between neurons.
Electrical synapses operate through what type of junction?
Gap junctions.
Interneurons are linked by what junction?
Gap junctions.
Which are more common: electrical or chemical synapses?
Chemical synapses.
What is the structure of the Calyx of Held synapse?
Large presynaptic terminal.
Large postsynaptic bouton.
What does the Calyx of Held allow us to do?
To record both pre- and postsynaptically.
Describe the calcium-dependent release from the Calyx of Held.
It is 4th order with a very steep curve and an extremely sensitive dependence on intracellular calcium concentration.
Describe the four features of synaptic transmission.
Non-linear.
Low probability.
Highly calcium dependent.
Quantal.
Describe the molecular mechanism of exocytosis during NT release.
Vesicle docks.
SNARE complexes form to pull membranes together.
Entering calcium binds to synaptotagmin.
This then catalyses membrane fusion by binding to SNAREs and the plasma membrane.
What is evoked NT release?
Action potential dependent release.
What is spontaneous NT release?
Action potential independent release.
