PharmoDynamics

Question 1

for drugs to produce their effects they must act on the body at cellular level. The five modes of drug-body action are

Answer 1

receptors, enzymes, carrier molecules (transport system) , ion channels

Question 2

Drug action receptors are found where

Answer 2

cell membranes

Question 3

drug action receptors are what type of cell

Answer 3

proteins

Question 4

‘agonist’ drug effect is ? (receptors)

Answer 4

mimics a substance is the body naturally produces

Question 5

‘antagonist’ drug effect is?(receptors)

Answer 5

block a natural receptors

Question 6

what is a partial agonist drug effect(receptors)

Answer 6

not as effective as agonist, may be beneficial if people are getting a lot of side effects . i.e. morphine to buprenorphine patch

Question 7

ion channels are located where

Answer 7

cell membrane

Question 8

ion channel functions

Answer 8

to allow ions to transport in and out of the cell

Question 9

ion examples

Answer 9

sodium, k, ca, mg

Question 10

medications which affect ion channels aim to do what

Answer 10

can block the ion channels within the cell preventing ions leaving

Question 11

example of an ion channel medication

Answer 11

calcium channel blockers

Question 12

Calcium channel blockers

Answer 12

prevent an influx of ca into the heart muscle - prevent ca coming into the cell, leading to an excitable state which starts contraction

Question 13

drug modulators (Ion channel)

Answer 13

these drugs bind to a receptor on the ion channel , changing the shape - may make it narrower or larger, resulting in a faster or slower flow

Question 14

drugs that work on enzymes - what is an enzyme

Answer 14

it needs to be present for a chemical reaction to occur - catalyst for the reaction to occur, the enzyme has to already be present.

i.e. the drug gets changed into its metabolite by the enzyme i.e. Codeine is given, it is changed by the enzyme into its metabolite - morphine

Question 15

pro drug example (enzymes)

Answer 15

codeine

Question 16

enzyme inhibitor

Answer 16

prevents the enzyme from doing its job

Question 17

enzyme inhibitor example drug

Answer 17

ace inhibitor (angiotensin converting enzyme inhibitor)

Question 18

Carrier proteins/molecule example

Answer 18

sertraline
work by extending the life of serotonin

Question 19

What is a receptor

Answer 19

a specialist area on the cell wall within the cellular cytoplasm, the drug will have an affect when it binds with the receptors.

Question 20

4 Main types of cell receptors

Answer 20

• Ligand-gated ion channels/ionotropic receptors
• Guanine nucleotide-binding protein (G-protein) receptors
• Kinase-linked receptors
• Nuclear receptors

Question 21

A ligand is a

Answer 21

molecule that binds to a receptor. It can be a hormone, neurotransmitter, intracellular messenger molecule or exogenous drug.

Question 22

G- proteins are found within the cell, are linked to what and activate after what

Answer 22

to the receptor and activate after drug molecule binding.

Question 23

Kinase linked receptors produce a

Answer 23

cascade of events after drug binding that lead to drug action.

Question 24

Nuclear receptors are located

Answer 24

WITHIN the cell nucleus and require the drug molecule to cross the nuclear membrane.

Question 25

Gaba A receptor is what type?

Answer 25

Ligand gated ion channel which binds benzodiazepines

Question 26

G-Protein examples are

Answer 26

Adreno-receptors and histamine receptors

Question 27

Kinase-Linked receptors target what

Answer 27

Insulin, cytokine receptors

Question 28

Nuclear receptors target what

Answer 28

thyroid & steroid receptors

Question 29

Receptors are affected by

Answer 29

both internal mechanisms and external factors and so affect the way the body adapts to drugs.

Question 30

A drug that binds to a receptor and causes activation is called an

Answer 30

agonist

Question 31

A drug that binds to a receptor and prevents activation is called an

Answer 31

antagonist

Question 32

Antagonists are

Answer 32

chemical molecules or drugs that bind to their target receptors to prevent naturally occurring substances within the body from binding to them.

Question 33

An agonist is a

Answer 33

chemical molecule that has the ability to activate a receptor’s cellular activity and promote a response. Many hormones, neurotransmitters and drugs act as agonists.

Question 34

As well as agonists and antagonists, there are also

Answer 34

partial agonists and inverse agonists. They can be competitive and non-competitive in their actions.

Question 35

autonomic nervous system receptor name

Answer 35

adrenoceptors

Question 36

b1 adrenoceptors are located where

Answer 36

in the heart

Question 37

b1 adrenoceptors when activated do what

Answer 37

increase HR

Question 38

b2 adrenoreceptors are located where

Answer 38

in smooth muscle inc. airway

Question 39

when b2 adrenoreceptors are activated what happens

Answer 39

the smooth muscle of the airway relaxes

Question 40

Specificity is ?

Answer 40

Chemical messengers interact with receptors by forming chemical bonds with them. Because chemical messengers and receptors are three-dimensional objects they have distinct shapes.

The shapes that fit best together allow the most bonds to form. In this way a receptor is able to distinguish between a chemical messenger - the true signal, and a similar compound that fits less well.

We refer to this as specificity. Consequently epinephrine binds with adrenoceptors, histamine binds with histamine receptors and so on.

Question 41

salbutamol is a

Answer 41

ß2 agonist that causes dilation of the airway and you might have guessed that its action makes it especially useful in an asthma attack