Block A Lecture 2: Where do Drugs Act?

Question 1

What are the top 2 receptor types which are targets for drugs?

Answer 1

G protein-coupled receptors (GPCRs) - 30%
Nuclear hormone receptors - 4%
(Lecture 2, Part 1, Slide 3)

Question 2

What do agonists and antagonists do to cell activity?

Answer 2

An agonist enhances cellular activity whereas an antagonist blocks cellular activity
(Lecture 2, Part 1, Slide 5)

Question 3

How can new drugs often be made?

Answer 3

By tweaking the structure of already existing drugs to try improve on their pharmacological properties
(Lecture 2, Part 1, Slide 7)

Question 4

Is salbutamol an agonist or antagonist?

Answer 4

Agonist (beta-2 adrenergic receptor)
(Lecture 2, Part 1, Slide 8)

Question 5

What is the first step of salbutamol’s mechanism of action to combat asthma?

Answer 5

Salbutamol activates ß-2 adrenergic receptors in the smooth muscle of bronchioles in the lung
(Lecture 2, Part 1, Slide 8)

Question 6

What happens in salbutamol’s mechanism of action after it activates ß-2 adrenergic receptors in the smooth muscle of bronchioles?

Answer 6

ß-2 adrenergic receptors, activate the enzyme adenylyl cyclase
(Lecture 2, Part 1, Slide 8)

Question 7

What happens in salbutamol’s mechanism of action after ß-2 adrenergic receptors activates the adenylyl cyclase?

Answer 7

It converts ATP into cyclic adenosine monophosphate (cAMP)
(Lecture 2, Part 1, Slide 8)

Question 8

What happens in salbutamol’s mechanism of action after adenylyl cyclase converts ATP into cyclic adenosine monophosphate (cAMP)?

Answer 8

cAMP inhibits calcium release, resulting in smooth muscle relaxation
(Lecture 2, Part 1, Slide 8)

Question 9

Are anti-histamines antagonists or agonists?

Answer 9

Antagonists
(Lecture 2, Part 1, Slide 11)

Question 10

What are anti-histamines antagonists for?

Answer 10

Histamine H1 receptors
(Lecture 2, Part 1, Slide 11)

Question 11

What do antihistamines treat?

Answer 11

Allergic reactions
(Lecture 2, Part 1, Slide 14)

Question 12

Are drugs mainly agonists or antagonists?

Answer 12

Antagonists
(Lecture 2, Part 1, Slide 15)

Question 13

What are beta blockers antagonists for?

Answer 13

Beta 1 receptors
(Lecture 2, Part 1, Slide 15)

Question 14

What are beta blockers used to treat?

Answer 14

Heart arrythmias (irregular heart beat)
(Lecture 2, Part 1, Slide 15)

Question 15

What do antagonists of histamine H2 receptors treat?

Answer 15

Stomach ulcers
(Lecture 2, Part 1, Slide 15)

Question 16

What do antagonists of angiotensin II receptors treat?

Answer 16

High blood pressure (by lowering it)
(Lecture 2, Part 1, Slide 15)

Question 17

What do antagonists of purinergic (P2y12) receptors on platelets treat and how?

Answer 17

Heart attacks - by inhibiting platelet aggregation
(Lecture 2, Part 1, Slide 15)

Question 18

Is the contraceptive pill an agonist or antagonist?

Answer 18

Agonist
(Lecture 2, Part 1, Slide 16)

Question 19

What type of drug is aspirin?

Answer 19

An enzyme inhibitor
(Lecture 2, Part 2, Slide 5)

Question 20

What is the full chemical name of aspirin?

Answer 20

Acetyl Salicylic Acid
(Lecture 2, Part 2, Slide 6)

Question 21

What does aspirin inhibit?

Answer 21

It inhibits both isoforms of the cyclo-oxygenase inhibitor (COX inhibitor), COX-1 and COX-2
(Lecture 2, Part 2, Slide 7)

Question 22

What is the cyclo-oxygenase inhibitor responsible for?

Answer 22

Converting arachidonic acid into TXA2 and PGE 2 prostaglandins
(Lecture 2, Part 2, Slide 7)

Question 23

What is PGE2?

Answer 23

A prostaglandin involved in inflammation
(Lecture 2, Part 2, Slide 9)

Question 24

What mediates the creation of PGE2?

Answer 24

COX-2
(Lecture 2, Part 2, Slide 9)

Question 25

What is TXA2 (thromboxane A2)?

Answer 25

A prostaglandin like product involved in platelet aggregation during clotting
(Lecture 2, Part 2, Slide 9)

Question 26

What mediates the creation of TXA2 (thromboxane A2)?

Answer 26

COX-1
(Lecture 2, Part 2, Slide 9)

Question 27

In addition to reducing inflammation by inhibiting COX-2, what else is aspirin good for and how does it do this?

Answer 27

Preventing secondary heart attacks (in combination with other drugs) - by inhibiting COX-1
(Lecture 2, Part 2, Slide 12)

Question 28

What is the full name of ACE inhibitors?

Answer 28

Angiotensin Converting Enzyme inhibitors
(Lecture 2, Part 2, Slide 13)

Question 29

What does ACE (Angiotensin Converting Enzyme) do?

Answer 29

Convert angiotensin I to II
(Lecture 2, Part 2, Slide 14)

Question 30

What are 3 examples of ACE inhibitors?

Answer 30

Captopril
Enalapril
Cilazapril
(Lecture 2, Part 2, Slide 18)

Question 31

How do ACE inhibitors lower blood pressure?

Answer 31

ACE is responsible for converting angiotensin I to II. Angiotensin II is a vasoconstrictor, which results in blood pressure increasing. ACE inhibitors inhibit ACE, preventing angiotensin II being formed, meaning vessels do not become constricted, lowering blood pressure
(Lecture 2, Part 2, Slide 19)

Question 32

What are 3 examples of enzyme inhibiting drugs (other than ACE inhibitors)?

Answer 32

Statins
Sildenafil (Viagra)
Nevirapine
Penicillin
(Lecture 2, Part 2, Slides 20 and 21)

Question 33

What do statins do?

Answer 33

Lowers cholesterol and prevents heart attacks
(Lecture 2, Part 2, Slide 20)

Question 34

What does sildenafil (Viagra) do and how?

Answer 34

It helps with erectile disfunction by inhibiting the enzyme which breaks down cGMP
(Lecture 2, Part 2, Slide 20)

Question 35

What is nevirapine used to treat and how does it treat it?

Answer 35

Used in treatment of HIV and AIDs as it is a non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1
(Lecture 2, Part 2, Slide 20)

Question 36

How does penicillin kill bacteria?

Answer 36

By the beta-lactam ring binding to DD-transpeptidase, inhibiting its cross linking activity and preventing a new cell wall being formed
(Lecture 2, Part 2, Slides 21 and 22)

Question 37

What happens to a bacteria that doesn’t have a cell wall due to penicillin?

Answer 37

It becomes vulnerable to outside water and molecular pressures, causing the cell to die quickly
(Lecture 2, Part 2, Slide 21)