Essential Pharmacology Flashcards Preview

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Flashcards in Essential Pharmacology Deck (18):
1

Can the same receptor on a cell be coupled to different responses?

Yes

2

What should the ligand be in order to bind to an intracellular receptor?

Hydrophobic/lipid soluble

3

Give an example of a ligand that is lipid soluble...

Steroid hormones

4

What do intracellular receptors often regulate?

Rate of transcription, often known as transcription factors

5

What are the 4 types of plasma receptors?

1. Ones with ion channels (ionotropic) - ligand gated channels

2. Receptors that act and enzymes

3. Receptors that regulate enzymes

4. G protein coupled

6

So what is the point of receptors?

They enable the specificity of the action of different transmitters and hormones

7

What is the largest class of plasma receptors?

G protein coupled

8

What happens when a G-protein receptor is coupled to adenylyl cyclase

It increases cAMP which activates PKA (if unbound will do the opposite)

9

What happens when a G-protein receptor is couples to Phospholipase C?

Produces DAG which activates PKC

AND

IP3 which releases Ca2+ ions

10

What are PKA and PKC used for?

For phosphorylation - therefore regulate a host of cell proteins

11

How do drugs act?

By interacting with a binding site - a receptor

12

What happens the more drugs that bind to the receptors?

There is a bigger response until all of the receptors are filled and then increasing drug level doesn't do anything...

13

What is efficacy?

Determines how good a drug is at activating a receptor - drugs can partially activate receptors

14

What is affinity?

How well the drug binds to the receptor

15

What is the affinity and efficacy of a full agonist?

High affinity
High efficacy

16

What is the affinity and efficacy of a partial agonist?

High affinity
Low efficacy

17

What is the affinity and efficacy of an antagonist?

High affinity
Little to no efficacy

18

Can one transmitter act on many receptor sub types? Give examples, do they always act like this?

Yes

Ach - agonist acts on all cholinergic receptors like nicotinic and muscarnic

Noradrenaline - agonist acting on all adrenergic receptors - alpha 1 an 2 and beta 1 an 2

But transmitters can also be selective