Inflammation 1 Flashcards Preview

BMS235 Physiology and pharmacology > Inflammation 1 > Flashcards

Flashcards in Inflammation 1 Deck (18)
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1
Q

How are prostaglandins normally produced

A

Phospholipids are metabolised by phospholipase A2 to form arachidonic acid - this is then metabolized by COX enzymes to form prostaglandins

2
Q

What are NSAIDs

A

Non-steroidal anti-inflammatory drugs - all are inhibitors of COX enzymes

3
Q

Describe COX-1

A

Ubiquitous and always active

4
Q

Why is COX-2 a more desirable target for anti-inflammatories?

A

Only turned on during the inflammatory response

inhibiting COX-2 doesn’t normal function and lead to side effects seen in COX-1 inhibition

5
Q

Where is COX-3 found?

A

CNS and kidneys - not expressed in the gut - target for paracetamol

6
Q

Why are NSAIDs said to be anti-inflammatory

A

Because the inhibit the production of prostaglandins

7
Q

How do NSAIDs reduce oedema

A

Prostaglandins are vasodilators - inhibition of this

8
Q

How are NSAIDs analgesic

A

Reduction of sensitization of nociceptors by prostaglandins

9
Q

How are NSAIDs antipyretic

A

In normal infection - Cytokine Il-1 induces the production of E-type prostaglandins through the action of COX-2 enzymes
By inhibiting this it therefore acts to lower raised temperatures

10
Q

Where are COX enzymes found

A

The endoplasmic reticulum

11
Q

Where is Arachidonic produced

A

At the plasma membrane - diffuses through the cytoplasm into the rough ER where it binds to the catalytic site of COX enzymes

12
Q

How does aspirin interact with COX enzymes

A

Covalently binds to serine residue in the COX enzyme

13
Q

How does aspirin interact with COX

A

Suicidal inhibition - once bound it is permanent - lasting effects of aspirin dependent on the time it takes for new COX enzymes to be produced - normally around four hours

14
Q

What are the main side effects of NSAIDs

A
  1. Stomach pain
    renal failure
    liver damage
    bronchospasm
15
Q

Why is nausea so common with the use of NSAIDs

A

Prostaglandins in the gut inhibit acid secretion and protect the gut mucosa - by inhibiting you get reduced mucous secretion

16
Q

What use does misoprostol have

A

Administered in conjunction with NSAIDs - it is a prostaglandin analogue who’s action is restricted to just the stomach so can alleviate some of the GI tract problems

17
Q

How do NSAIDs affect renal blood flow

A

Reduced prostaglandins = reduced renal blood flow - stronger NSAIDs can cause renal failure

18
Q

How do NSAIDs affect the liver

A

Especially true for paracetamol - metabolism in the liver produces a toxic intermediate that kills off liver cells - normally quickly converted but in overdose can have an overwhelming effect