Synapses and the role of neurotransmitters

Question 1

What is the structure of an electrical synapse (gap junction)?
Where are they common?

Answer 1

6 connexins = 1 connexon
Common glia-neurone or glia-glia
More common in developing NS

Question 2

What is the most abundent NT? What is its structure?

Answer 2

glutamate

amino acid

Question 3

What are the two receptor signalling mechanisms?

What is the difference?

Answer 3

ionotropic - receptor operated/ligand gated channels (fast)

metabotropic - GPCR’s, indirect effects e.g. secondary messenger systems, enzyme pathways (slower)

Question 4

Give examples of each type of receptor signalling mechanism

Answer 4

ionotropic = glutamate, AMPA, NMPA, ACh nicotinic
metabotropic = ACh muscarinic, GABAb

Question 5

What is spatial summation?

Answer 5

summing of post synaptic potentials generated at separate synapses

Question 6

What is temporal summation?

Answer 6

summing of post synaptic potentials generated at same synapse, if they occur in rapid succession