Molecular Bioogy of Receptors

Question 0

Describe the structure of a metabotropic receptor?

Answer 0

Monomeric, 7-TM domains, extra cellular for NT binding and intracellular for G-proteins

Question 1

What are three tetrameric ionotropic receptors for glutamate?

Answer 1

AMPA, NMDA and kainate

Question 2

What inhibits GABAa receptors?

Answer 2

Picrotoxin inhibits by blocking chloride ions and changing the membrane potential to be further from threshold.

Question 3

How many subunits can ionotropic receptors have?

Answer 3

3,4 or 5

Question 4

How many helices do the ionotropic receptors have?

Answer 4

4 or 3 with a pore loop

Question 5

What lines the channel of an ionotropic receptor?

Answer 5

Either the second helice or the pore loop. They control the flow

Question 6

What the ways can ion channels be opened by?

Answer 6

Chemicals (ligand-gated), voltage, and mechanosensory

Question 7

Describe the structure of a nicotinic acetylcholine receptor and what is it permeable to?

Answer 7

5 subunits, 4 helices in each. Acetylcholine binds to the alpha subunits. Permeable to sodium and potassium and sometimes calcium

Question 8

What are the two types of receptors?.

Answer 8

1. Ligand-gated ion channels or ionotropic

2. G-protein coupled receptors or metabotropic.

Question 9

How do ionotropic receptors work?

Answer 9

Several proteins form a channel when NT binds the channel opens, either cationic or anionic, rapid.

Question 10

Explain how NMDA receptors work?

Answer 10

At resting potential the channel is blocked by magnesium, it’s only active drying high frequency stimulation. Magnesium is exposed post-depolarisation as driving force is removed, glycine is a co-agonists and D-Serine.

Question 11

How many classes of different G-protein coupled receptors are there?

Answer 11

8- glutamate, GABAb, dopamine, noradrenaline, adrenaline, histamine, serotonin, purines and muscarinic.