How Drugs Act 1

Question 1

What is Pharmacolgy

Answer 1

The branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function.

Question 2

What is a drug

Answer 2

: Broadly defined as any man-made, natural, or endogenous (within the body) molecule which exerts a biochemical and/or physiological effect on the cell, tissue, organ, or organism/A drug is a chemical applied to a physiological system that affects its function in a specific way.

Question 3

How much does the UK spend on Medical drugs per annum?

Answer 3

£10bn p.a.

Question 4

How much does the UK spend on non Medical drugs per annum?

Answer 4

c.a. £30bn p.a. (£500 per person)

Question 5

Aside from medical drugs, what other drugs is the UK spending money on?

Answer 5

Sport enhancement (anabolic steroids, EPO)
Mood change (Alcohol, nicotine, caffeine)
Recreational (cannabis, cocaine, ketamine)
Herbal (St. John’s Wort, Milk Thistle)
Homeopathy (placebo effect)

Question 6

what do drugs act on and give examples

Answer 6

drugs act on target proteins, namely: receptors
enzymes
carriers
ion channels.

Question 7

what is a rececptor in terms of pharmacoly

Answer 7

protein molecules whose function is to recognise and respond to endogenous chemical signals

Question 8

what are drug targets?

Answer 8

Other macromolecules with which drugs interact to produce their effects are known as drug targets

Question 9

what is the nature f drug specificity

Answer 9

reciprocal: individual classes of drug bind only to certain targets, and individual targets recognise only certain classes of drug.

Question 10

are drugs completely specific in their actions? if not, why?

Answer 10

•No drugs are completely specific in their actions. In many cases, increasing the dose of a drug will cause it to affect targets other than the principal one, and this can lead to side effects.

Question 11

give examples of non receptor targets

Answer 11

Plant Sterols (cholesterol lowering)
Ammonium hydroxide (anti-pruritic)
Alcohol (sedative/hypnotic)

Question 12

give examples of receptor targets

Answer 12

Salbutamol (b2 adrenoceptors)
Sildenafil (PDE5)
Ibuprofen (COX-2)

Question 13

what confers the specificity of the drug?

Answer 13

is the chemical nature of the drug/receptor

Interaction that confers specificity

Question 14

how are we able to target specific tissue?

Answer 14

by choosing the receptors

Question 15

In Hypertensin, Ramipril is used. What is the receptor

Where is the receptor found and where is the not found

Answer 15

Angiotensin converting enzyme (ACE)
Present in smooth muscle in kidney and vasculature
NOT present in gut

Question 16

In Asthma, Salbutamlol is used. What is the receptor and what can this often get confused with

Answer 16

b2 adreneric
Present in airway smooth muscle
NOT present in cardiac muscle (b1)

Question 17

In Psychosis , Eticlopride l is used. What is the receptor

Where is the receptor found

Answer 17

: D2 dopamine receptor

Present in neocortical brain regions

Question 18

What is timecourse?

Answer 18

Time for the drug to reach the receptor
Binding rate constants
Activation/inactivation of receptor
Time for the drug to be removed from tissues

Question 19

what is pharmacodynamics

Answer 19

The study of drug-receptor interactions

Question 20

what is Dissociation constant

Answer 20

the concentration at which half of the drug is bound to the receptor at equilibrium.

Question 21

what is affinity

Answer 21

The strength of noncovalent bonds between drug and receptor (DR), as measured by the dissociation constant (Kd) of the DR complex.

Question 22

what is specificity

Answer 22

the degree to which the effects of a drug are due to the one pharmacological action.

Question 23

what happens at equilibrium dissociation

Answer 23

association, Kd = Ka

Question 24

what is Kd

Answer 24

equilibrium dissociation constant

Question 25

what is Koff

Answer 25

dissociation rate cnstant or ff rate constant

Question 26

what is Kon

Answer 26

association constant or on rate constant

Question 27

Agonist

Answer 27

: A drug that produces a positive effect when bound to a receptor.

Question 28

Potency

Answer 28

The dose of drug required to produce a specific effect of given intensity (depends on efficacy and affinity)

Question 29

Efficacy (Emax):

Answer 29

The maximum response achievable from a drug.

Question 30

Inverse agonist:

Answer 30

A drug that produces a negative effect when bound to a receptor.

Question 31

Antagonist

Answer 31

A drug that reduces the effect of an agonist at a given receptor

Question 32

what happens if binding is linearly proportional to effect

Answer 32

50% response = 50% binding (Kd)

Question 33

what are the 4 main types of receptor

Answer 33

Ligand gated ion channels G protein coupled receptors Receptor Kinases Nuclear receptors

Question 34

Ligand gated ion channels location

Answer 34

Membrane

Question 35

G protein coupled receptors location

Answer 35

Membrane

Question 36

Receptor Kinases receptors location

Answer 36

Membrane

Question 37

Nuclear receptors location

Answer 37

Intracellular

Question 38

Ligand gated ion channels effector

Answer 38

ion channel

Question 39

Ligand gated ion channels coupling

Answer 39

direct

Question 40

Ligand gated ion channels examples

Answer 40

nicotinic AcH GABA

Question 41

Ligand gated ion channels structure

Answer 41

Oligiomeric assessmbly of subunits surrounding central pore

Question 42

G protein coupled receptors effector

Answer 42

channel or enzyme

Question 43

G protein coupled receptors coupling

Answer 43

g protein

Question 44

G protein coupled receptors examples

Answer 44

muscarinic AcH receptor, adrenreceptors

Question 45

G protein coupled receptors structure

Answer 45

monometric or oligometric assembly f subunits comprising f 7 transmembrane helices with intracellular G protein coipling domain

Question 46

Receptor Kinases effector

Answer 46

protein kinases

Question 47

Receptor Kinases receptors coupling

Answer 47

direct

Question 48

Receptor Kinases receptors examples

Answer 48

insulin growth factors and cytokine receptors

Question 49

Nuclear receptors effector

Answer 49

gene transcription

Question 50

Nuclear receptors coupling

Answer 50

via DNA

Question 51

Nuclear receptors examples

Answer 51

steroid receptors

Question 52

Nuclear receptors structure

Answer 52

monomeric structure with separate receptor and DNA binding domains

Question 53

Receptor Kinases effector structure

Answer 53

single transmembrane helix linking extracellular receptor domain to intracellular kinase domain