12 Pharmacology Introduction

Question 1

Pharmacology definition

Answer 1

the study of effect of drugs on the function of living systems (with respect to therapeutic drugs)

Question 2

What’s involved in pharmacology (4)

Answer 2

Discovery and development of new medicinal products to treat disease

Improve drug effectiveness and reduce unwanted side effects

Understanding individual variation in drug response

Undertsanding why some drugs cause tolerance of addiction

Question 3

Physiology/Pathophysiology - multicellular organism chemical communication

Answer 3

Multicellular organisms have a system of chemical communication they use to coordinate their cells and organs

Question 4

Physiology/Pathophysiology - endogenous chemical evolution

Answer 4

Endogenous chemical molecules have evolves to fine-tune the control of cells and physiological functions (eg. Neurotransmitters and hormones)

Question 5

Drug definition

Answer 5

substance when introduced to the body produces a biological effect for an intended purpose

Question 6

Poison definition

Answer 6

Intended to have harmful effect on the body

Question 7

Drug and poison link

Answer 7

All drugs are poisons - the dose determines that a thing isn’t poison - at therapeutic levels drugs are safe and effective

Question 8

Where do drugs come from (3)

Answer 8

1. Natural products - plants / microbes / animals
2. Changing structure of an existing molecule
3. Serendipity (“by accident“)

Question 9

Where do drugs come from - natural products

Answer 9

Poppy - morphine (painkiller / addictive) —> heroin (addictive illegal drug)

Salicylic acid (painkiller - very bitter non-compliance) —> aspirin (painkiller)

Both of these were converted from the 1st substances to the 2nd but Dr Felix Hoffman (semi-synthetic 1898-1899)

Question 10

Where do drugs come from - serendipity

Answer 10

Sildenafal - developed as an anti-angina drug (now known as viagra - billion dollar blockbuster for Pfizer)

Question 11

Molecule to man

Answer 11

Select disease (indication) —> identify target (protein, DNA etc.) —> synthesis selective ligand —> assess function

Question 12

When do drugs not work

Answer 12

Molecules in an organism vastly outnumber drug molecules —> random drug distribution throughout the body - no pharmacological effect

A drug wont work unless it is bound’

Question 13

Pharmacokinetics pathway

Answer 13

Drug administration

Absorption

Distribution (intra/extravascular space / protein binding / tissue stores

Metabolism

Excretion

Question 14

Pharmacodynamics pathway

Answer 14

Transfer to the site of action from pharmacokinetics distribution

Drug concentration at the site of action (interaction with regulatory proteins)

Molecular targeting

Drug mechanisms of action (MOA)

Response to drug (efficacy and toxicity)

CLINICAL OUTCOMES

Question 15

Pharmacodynamics

Answer 15

“the effect of drug on the body”

Pharmacodynamics investigates the mechanisms of drug action - including molecular, cellular and physiological effects of a drug relationship between drug concentration and effect.

Confirms drug safety and efficacy / minimises adverse effect / optimum doagase

Question 16

Drug targets include cellular coupons at…

Answer 16

Receptors / ion channels / transporters / enzymes

Extracellular / cell membrane / intracellular

Question 17

Ways a drug interacts with a target to produce a biological effect, whats this determined by?

Answer 17

Intermolecular forces, steric match and the type of bond formed

Question 18

Small molecule drug binding site (description)

Answer 18

defined pocket/cavity in the structure of the drug target

Question 19

Where may drug-target interaction occur

Answer 19

at the active or orthostatic site (endogenous interactions occur)

allosteric site elsewhere on the drug target

Question 20

Why do some drugs bind to their targets reversibly and some irreversibly

Answer 20

Depend on bond types formed

Question 21

Affinity

Answer 21

Binding strength of a drug to a target

Question 22

Drug efficacy

Answer 22

Ability of a drug to elicit a response once bound to drug target

Question 23

Agonists

Answer 23

endogenous or exogenous molecules that have affinity for and efficacy at a receptor to elicit a biological response

Question 24

Antagonists

Answer 24

molecules that have affinity for a receptor to limit the effect of agonists but lack intrinsic efficacy

Question 25

Drug selectivity - whats it determined by

Answer 25

Determined by affinity and efficacy for one target vs another

Each drug target recognises only a small number of molecules of which have some structural similarity (eg. Histamine receptors)

Question 26

What are different receptors for the same endogenous agonists called?

Answer 26

Subtypes

some drugs exhibit selective activity towards different subtypes

Question 27

Potency

Answer 27

• Among of drug expressed as a concentration or dose needed to produce a defined effect

Question 28

Mechanisms of drug actions, what does this refer to

Answer 28

process by which a drug produces a biological effect

Question 29

On what levels can mechanisms of drug actions be observed

Answer 29

Can be observed at multiple levels - molecular, cellular, physiological events that produce the observed outcomes

Question 30

Mechanisms of drug action - what does this include

Answer 30

may involve blocking, limiting, activating or enhancing a physiological process

Question 31

… have specilised by physiological function

Answer 31

Targeted cells / tissues