Drug Targets + key info

Question 1

What is pharmacodynamics definition

Answer 1

Effect of drugs on the body itself

Question 2

What 2 things are looked at in pharmacodynamics

Answer 2

The molecular interactions Drugs have effect on
Eg, effect on target,cell response

Influence of DRUG DOSAGE

Line between toxic and therapeutic

Question 3

How do we use pharmacodynamics

Answer 3

To find suitable dosage and know effect the drug has at good concentration

Question 4

What is pharmacokinetic definition

Answer 4

The effect the body had on the drug

Question 5

What 4 things are looked at in pharmacokinetics

Answer 5

1- absorption or drug into blood stream

2- distribution Eg into ICF of some tissues from the blood

3- metabolism to inactivate the drug

4- excretion of the drug in urine or faeces

Question 6

Why is pharmacokinetics individual optimal rather than general dosage

Answer 6

Peoples metabolism affects how frequently you need to take the drug

Question 7

Why don’t drugs only treat area applied

Answer 7

They are absorbed in blood stream

Question 8

Drugs can be natural or synthetic. Give example or natural drugs

Answer 8

Laxanes from plants for anti cancer

Question 9

What are the subdivisions of synthetic drugs

Answer 9

Completely artificial- codeine

Derived from something in body - insulin engineered

Question 10

What are drugs which are synthetic but are usually in body called

Answer 10

Biologics

Question 11

What 5 ways do drugs interact with targets / body

Answer 11

1- lock and key shape dependent

2- charge / bond dependant

3- hydrophobicity

4- stereochemistry

5- ionisation changes in different ph / pka

Question 12

How can weak bond / charges between drugs and target affect response

Answer 12

It is short term solution drug will unbind

Question 13

What 4 target proteins for drugs are there

Answer 13

Receptors

Ion channels either ligand or voltage

Enzyme

Carrier/channel proteins

Question 14

What 3 drugs have effect due to chemistry not targets

Answer 14

Laxatives - have lactulose which adds water to stool

Antidotes - acetylcysteine stops paracetamol overdose

Antacids - alkaline to neutralise stomach acid

Question 15

What are agonists and give examples

Answer 15

They mimic the action of endogenous chemical messengers

Eg hormones, histamine on H1 receptors, prostaglandins

Question 16

What are the effects of agonists on the 4 targets

Answer 16

Receptors - activated

Ion channels - modulated

Enzymes - activated

Carrier - enhanced

Question 17

What are antagonists

Answer 17

Drugs that inhibit action of agonists and arent endogenous

Question 18

What is the effects on 4 target proteins due to antagonists

Answer 18

Receptors - inactive

Ion channels - blocked

Enzymes - inhibited allosterically or non competitively

Carriers - inhibited

Question 19

How is aspirin an example of an agonist NSAID

Answer 19

It binds to the enzyme cyclooxgenase irreversibly

Stops prostaglandin production (inflammatory agent)

Question 20

How can benzodiazepines be an agonist

Answer 20

It binds to the gaba ligand channel either on the allosteric or Orthosteric site

If it binds to allosteric site as gaba, this increases effect of gaba = more Cl

Question 21

Why is benzodiazepines good for anxiety

Answer 21

It causes sleep due to hyperpolarisation of opening Cl channels

Question 22

What is the main example of a receptor drug and explain it

Answer 22

SALBUTAMOL

Agonist to the B2 adrenogenic receptor present in lungs

Causes Gs activation and adenylate Cyclase activity

Causes bronchi-dilation for asthma sufferers

Question 23

Give example of an ion channel drug

Answer 23

LIDOCAINE ANAESTHETIC

it is an antagonist to the na voltage channel

Causes stop flow of na

No ap = sedation

Question 24

Other than aspirin, give another enzyme target drug

Answer 24

Penecillin which is an antagonist to transpeptidase work

Breaks down the cell wall

Question 25

Give an example of a carrier protein targeting drug

Answer 25

Omeprazole which is an antagonist to H pump to stop flow of acid in the stomach to treat ulcers

Question 26

Why are different receptor subtypes important eg the different histamine receptors

Answer 26

They have different drugs which can block them at different sites of body to stop drug having multiple effects

Question 27

What do antagonists do to receptor

Answer 27

Stop transduction

Question 28

Give an example of a ligand ion channel affected by antagonists

Answer 28

Nicotinic ach receptor which if blocked by antagonist stops contraction and ap

Question 29

What 3 subunits does the alpha have in GCRP

Answer 29

Gs- stimulating: activates adenylate cyclase or ca channels Gi- inhibiting : inhibits adenylate cyclase or opens K channels Gq - activates phospholipase c for Ca2 release

Question 30

Give an example of a GCRP subtype

Answer 30

Adrenergic receptors (like salbutamol B2 action)

Question 31

What happens to Alpha 1 adrenergic receptor

Answer 31

It has its Gq subunit activated Activates phospholipase c Releases ca from sr Vasoconstriction of muscle

Question 32

What happens to the alpha 2 adrenergic receptor

Answer 32

It’s Gi subunit is activated and therefore stops adenylate cyclase activation No pka activated Causes no neurotransmitter release

Question 33

What is the B1 adrenergic receptor function

Answer 33

It’s Gs is activated Activates adenylate cyclase Causes increased HR in the cardiac muscle (Due to na channels opening) - adenylate cyclase causes NT release

Question 34

What happens when a drug stops usual epinephrine action to increase HR on the alpha 1 adrenergic receptor

Answer 34

Epinephrine can’t bind The alpha 1 receptor doesn’t activate adenylate cyclase This causes no NT release No NA channels open

Question 35

What subunit is activated in the B2 adrenergic receptor which salbutamol is agonist to

Answer 35

It causes activation of Gs which causes active adenylate cyclase and therefore Bronchidilation

Question 36

Name 4 enzyme linked receptors

Answer 36

Insulin/ RTK Guanylyl cyclase linked receptor Serine/threonine kinase receptor Cytokine receptor

Question 37

WhT are the 2 classes of nuclear/intracellular receptor

Answer 37

Class 1- in cytosol and is a homodimer , binds to hormones Class 2- in nucleus , is a hetereodimer , binds to fatty acids

Question 38

What do receptors have in terms of binding sites

Answer 38

Multiple sites drugs binds to

Question 39

How many binding sites do glycine receptors have on ion channel

Answer 39

4

Question 40

How many binding sites do nicotinic ach have

Answer 40

Homomers have 5 Hetereomers have 2

Question 41

Which sites to competitive drugs bind to eg benzodiazepines on gaba channel

Answer 41

Orthosteric to enhance gaba activity