Neural communication 2

Question 1

Ionotropic receptors/channels

Answer 1

Ligand-gated ion channels
Modulatory roles
Fast, transient effect. Temporary in nature
1- NT binds, 2- channels open, 3- Ions flow across membrane

Question 2

Metabotropic receptors

Answer 2

G-protein-coupled receptors (GPCR)
Activates other channels by activating proteins that do that (no direct change of voltage)
Modulate signals 
Slow, longer lasting effect
Signal cascades

Question 3

Extrasynaptic receptors

Answer 3

these receptors are on the edges of the synapse site

Question 4

Autoreceptors

Answer 4

Bind to the same NT that its neuron releases
Negative feedback mechanism
Too many NTs released = overflow at border = autoreceptor activates = neuron stops releasing NTs

Question 5

Heteroreceptors

Answer 5

Receptor that binds to a neurotransmitter that is not part of the synapse.
Can turn up or down the release baseline activity of NTs (the existing signal)
NTs that bind to it might come from other axons next to them or from the fluid

Question 6

Neurotransmitter clean-up

Diffusion

Answer 6

• NTs just float away

Question 7

Neurotransmitter clean-up

Enzymatic degradation

Answer 7

breaks NTs down so that they don’t bind to sites anymore

Question 8

Neurotransmitter clean-up

Re-uptake

Answer 8

NTs go back into the axon using a transporter - can act on vesicles and axon membrane
NTs can go back to Presynaptic axon or Astrocytes