Chemistry - Pharmacodynamics

Question 1

What are the Physiological responses produced through drug-receptor interactions?

Answer 1

• Change in contractility of a tissue
• change in neuron excitability
• change in gene transcription

Question 2

What dictates the extent of the change produced through drug-receptor interactions?

Answer 2

Depends on the drugs affinity and efficacy

Question 3

What is an agonist?

Answer 3

Drug binds and activates receptor

Question 4

What is a partial agonist?

Answer 4

Binds and activates a receptor, but not as well as the agonist

Question 5

What is an antagonist?

Answer 5

Binds to a receptor, but doesn’t activate so prevents the agonist

Question 6

What is a competitive antagonist?

Answer 6

Binds to the same site as the agonist

Question 7

What is a non-competitive antagonist?

Answer 7

Binds to an allosteric site on the receptor to prevent activation

Question 8

Do competitive antagonists bind reversibly or irreversibly?

Answer 8

Reversibly

Question 9

Do non-competitive antagonists bind reversibly or irreversibly?

Answer 9

irreversibly

Question 10

What are inverse agonists?

Answer 10

Produce a net decrease in the receptors activity

Question 11

What are allosteric interactions?

Answer 11

Secondary binding sites that change the affinity of the primary binding site, by changing its conformation

Question 12

What is affinity?

Question 13

What is potency?

Answer 13

The amount of a drug required to produce an effect of given intensity

Question 14

What is efficacy?

Answer 14

The ability of a drug to elicit a physiologic response when it interacts with a receptor

Question 15

What is Specifity?

Answer 15

How specific a drug is to a receptor

Question 16

What are examples of membrane targets?

Answer 16

Cellular receptors

ion channels, pumps and transporters

Question 17

What are examples of large protein targets?

Answer 17

Enzymes

Carrier proteins

Question 18

What is autocrine?

Answer 18

A cell secretes a hormone or chemical messenger that binds to autocrine receptors on that same cell, leading to changes

Question 19

What is paracrine?

Answer 19

A cell produces a signal that induces change in nearby cells, altering the behaviour of those cells

Question 20

What is the chief neurotransmitter of the parasympathetic nervous system?

Answer 20

Acetylcholine (ACh)

Question 21

What are cell surface receptors?

Answer 21

Receptors embedded in the plasma membrane of cells that allow communication between the cell and the extracellular space

Question 22

What prevents a substance from passing through the cell membrane?

Answer 22

Ions or Polar and Large molecules

Question 23

What are the two main types of surface receptor?

Answer 23

G protein coupled and kinase receptors

Question 24

What are G protein receptors?

Answer 24

Receptors that release a alpha sub unit when the G protein is activated. The sub unit will then activate/deactivate an enzyme or ion channel within the cell

Question 25

What is atropine?

Answer 25

A antagonist drug which binds to muscarinic receptors

Question 26

What does atropine do in the heart?

Answer 26

removes vagal inhibition. Modest tachycardia.

Question 27

What does atropine do in the gastro-intestinal tract?

Answer 27

removes parasympathetic stimulation: motility is reduced. Secretions reduced

Question 28

What does atropine do in Smooth muscle?

Answer 28

blocks constriction: dilatation

Question 29

What does atropine do in the eye?

Answer 29

unbalanced sympathetic causes mydriasis

Question 30

What does atropine do in the neural?

Answer 30

many effects including vagal stimulation! (paradoxical bradycardia at low dose)

Question 31

What are catecholamines?

Answer 31

Hormones made by your adrenal glands which help with the ‘‘fight or flight response’’

Question 32

What are the 3 main catecholamines?

Answer 32

Dopamine

Adrenaline

Noradrenaline

Question 33

Where are a1 receptors mainly found?

Answer 33

Vascular smooth muscle

Question 34

What happens when adrenaline activates an a1 receptor?

Answer 34

Causes constriction

Question 35

Where are b1 receptors mainly found?

Answer 35

Found mainly on heart muscle cells

Question 36

What happens when adrenaline activates b1 receptors?

Answer 36

Increases rate and force of contraction

some effect on skeletal muscle

Question 37

Where are b2 receptors mainly found?

Answer 37

Mainly smooth muscle (including respiratory)

Question 38

What happens when adrenaline binds to b2 receptors?

Answer 38

Relaxation

glycogenolysis

Question 39

What are the side effects when adrenaline binds to a1?

Answer 39

Vasoconstriction increases blood pressure for given cardiac output

Question 40

What are the side effects when adrenaline binds to b1?

Answer 40

Increased rate and force of heart contraction

tachycardia and anxiety

Question 41

What are the side effects when adrenaline binds to b2?

Answer 41

Bronchodilatation

Increased blood sugar

skeletal muscle-tremor

Question 42

What are nuclear receptors?

Answer 42

located in the cytosol, they cause changes in gene expression and therefore protein synthesis over hours or days

Question 43

What are kinase linked receptors?

Answer 43

A transmembrane receptor, which causes phosphorylation of amino acids - mainly tyrosine - within the cell, when the drug binds to the receptor-binding site.

Question 44

How do insulin receptors enable glucose to enter the cell?|

Answer 44

2 insulin molecules bind to the receptor causing the phosphorylation of amino acids within the cell, this leads to a channel being created in the membrane to allow glucose to enter the cell

Question 45

What is GTN?

Answer 45

A powerful venodilator which widens blood vessels increasing the blood supply to your heart, reducing chest pain

Question 46

What are side effects of GTN?

Answer 46

Reduced BP causes dizziness and a reflex increase in heart rate

tachycardia

Headache