Drug Receptors

Question 1

G-protein receptors can have a large effect with a small dose, true or false?

Answer 1

True.

Question 2

An example of a kinase-linked receptor is?

Answer 2

Insulin receptor.

Question 3

Kinases do what?

Answer 3

Add phosphate groups to proteins.

Question 4

Muscarinic ACh receptor is an example of what kind of receptor?

Answer 4

G-Protein-coupled receptors.

Question 5

_______ + Enzyme = ________

Answer 5

Substrate + Enzyme = Product

Question 6

G-proteins are inactive when bound to ________

and active when bound to: ________.

Answer 6

GDP, GTP.

Question 7

Kinase-linked receptors can cause an effect in what sort of time scale?

Answer 7

Kinase-linked receptors can cause an effect in what sort of time scale?

Question 8

Explain why small quantities of metabotropic ligand can produce large-scale cellular reponses.

Answer 8

Because when a metabotropic receptor is bound, it releases multiple G-proteins, which in turn activate, multiple primary effectors, which each in turn activate multiple secondary messengers, which in turn each activate secondary effectors, which in turn all produce some small amount of a cellular response – but by that point, the one ligand has caused at least 24 cellular responses (assuming each step only produces two products – which is very conservative). It’s cellular amplification of a signal!

Question 9

Antiporter transporter proteins transport how many molecules in which direction?

Answer 9

Two molecules in opposite directions.

Question 10

nACh, GABAA, NMDA, 5-HT and the Glycine Receptor are all examples of what type of receptor?

Answer 10

Ionotropic.

Question 11

G-protein-coupled receptors can cause an effect on what sort of time scale?

Answer 11

Seconds.

Question 12

Muscarinic ACh receptors and Adrenoreceptors are examples of what kind of receptor?

Answer 12

Metabotropic receptors or G-protein coupled receptors.

Question 13

An intracellular receptor is also known as a… ?

Answer 13

Nuclear Receptor

Question 14

Nicotinic ACh receptor is an example of what type of ion channel?

Answer 14

Ionotropic or Ligand-gated ion channel.

Question 15

Primary effectors of G-protein subunits include?

Answer 15

Ion channels and enzymes.

Question 16

Ionotropic receptors are also known as?

Answer 16

Ligand-Gated Ion Channels.

Question 17

Ionotropic receptors are usually homomeric, true or false?

Answer 17

False. Often heteromeric.

Question 18

What is a secondary effector? What process is it related to re: Drug Receptors? Give an example of one secondary messenger.

Answer 18

It is a step in a chemical signalling pathway that is a part of a cascade for G-protein coupled receptors. Secondary messengers go on to activate secondary effectors, causing a cellular response.

An example is cAMP.

Question 19

G-proteins can act to both inhibit or excite a primary effector, true or false?

Answer 19

True!

Question 20

A G-protein is what?

Answer 20

A membrane hugging complex. It comprises of sub-units that split when activated and which each then move to a downstream primary effector.

Question 21

Nicotinic ACh Receptor is often found where, has how many subunits and mos predominantly lets which ion through the cell membrane?

Answer 21

Often found in neuromuscular junctions and has 5 subunits, most permeable to sodium ions or potassium.

Question 22

Metabotropic Receptors are also known as?

Answer 22

G-Protein coupled receptors.

Question 23

Symporter proteins exchange how many molecules and in which direction?

Answer 23

Two molecules in the same direction.

Question 24

Ligand-gated ion channels can cause an effect in what sort of timescale?

Answer 24

Milliseconds.

Question 25

Nuclear receptors can cause an effect on what sort of time scale?

Answer 25

Hours.