Enzyme Action

Question 1

What are NSAIDs? What are some examples of them?

Answer 1

Non-steroidal anti-inflammatory drugs –> inhibit enzymes

Ibuprofen, aspirin

Question 2

What is job of NSAIDs?

Answer 2

Block COX enzymes and reduce production of prostaglandins

Question 3

What are prostaglandins?

Answer 3

Chemicals that:

1. Promote inflammation, pain, and fever
2. Protect lining of stomach and intestines from acid
3. Promote blood clotting

Question 4

What enzymes produce prostaglandins?

Answer 4

COX (COX1 and COX2)

Both COX1 and 2 produce prostaglandins that promote inflammation, pain and fever.

Only COX1 produces prostaglandins that activate platelets and protect stomach and intestinal lining

Question 5

What are good effects of NSAIDs?

Answer 5

Inflammation, pain and fever are reduced

Question 6

What are bad effects of NSAIDs?

Answer 6

1. Can cause stomach/intestine ulcers
2. Increased risk of bleeding
3. Fluid retention (long term taking of drug)

Question 7

How can aspirin lead to fluid retention?

Answer 7

Aspirin bypasses blood flow to kidneys

Question 8

What is RAAS? What is its function?

Answer 8

Renin-angiotenisn aldosterone system - regulates blood pressure, sodium conc, water volume in blood

Question 9

What is the mechanism that RASS works?

Answer 9

1. Drop in blood pressure
2. Kidneys detect change in water conc in blood
3. Release of renin
4. Converts angiotensin into angiotensin 1 via liver
5. Goes to lungs where angiotensin converting enzyme produces angiotensin II
6. This has role in vasoconstriction, causing blood pressure to go back up
7. Angiotensin II also works on adrenal cortex to release aldosterone which increases blood pressure

Question 10

How does aldosterone cause increase of blood pressure?

Answer 10

Aldosterone has role in water reabsorption and decreases urine volume which increases blood pressure

Question 11

What inhibitors stop action of angiotensin converting enzyme? What is result of this?

Answer 11

ACE inhibitors

Stops pathway before angiotensin II production - prevents vasoconrtsiction, increase in blood pressure and water reabsorption

Question 12

What is side effect of ACE inhibitors?

Answer 12

Can cause dry cough - prevents breakdown of Bradykinin which accumulates

Question 13

What is function of ARBs?

Answer 13

Stops action of angiotensin II by binding to active site

Question 14

What is raised blood pressure caused by?

Answer 14

Too much angiotensin II being formed and too much reabsorption

Question 15

What can aspirin cause?

Answer 15

More stomach acid production

Question 16

What are most COX inhibitors?

Answer 16

Non-selective and inhibit activity of both COX1 and 2

Question 17

What are effects of COX2 selective inhibitors?

Answer 17

Less gastrointestinal side effects but promote thrombosis –> increases risk of heart attack

Question 18

Are NSAIDS specific?

Answer 18

No - non-selective

Question 19

Can ARBs and ACEs be used at the same time?

Answer 19

No

Question 20

What is the difference between COX1 and 2?

Answer 20

COX1 is constitutional –> produces prostaglandins under basal conditions

COX2 is inducible –> Upregulated during inflammation

COX1 produces inflammatory prostaglandins as well as cytoprotective prostaglandins

COX2 only produces inflammatory prostaglandins

Question 21

What is job of cytoprotective prostaglandins?

Answer 21

• Protect gastric mucosa
• Protect renal perfusion
• Thromboxanes
• Aid platelet aggregation (adhesion)

Question 22

What is function of inflammatory prostaglandins?

Answer 22

• Recruit inflammatory cells (inflammation, vasodilation)

- Sensitive skin pain receptors

Question 23

What does tissue injury lead to?

Answer 23

Arachidonic acid –> COX1 and COX2 (important in arachidonic acid metabolism)

Question 24

What can acid lead to?

Answer 24

More stomach acid production