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Flashcards in Inflammation 1 Deck (18)
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How are prostaglandins normally produced

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


What are NSAIDs

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


Describe COX-1

Ubiquitous and always active


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

Only turned on during the inflammatory response
inhibiting COX-2 doesn't normal function and lead to side effects seen in COX-1 inhibition


Where is COX-3 found?

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


Why are NSAIDs said to be anti-inflammatory

Because the inhibit the production of prostaglandins


How do NSAIDs reduce oedema

Prostaglandins are vasodilators - inhibition of this


How are NSAIDs analgesic

Reduction of sensitization of nociceptors by prostaglandins


How are NSAIDs antipyretic

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


Where are COX enzymes found

The endoplasmic reticulum


Where is Arachidonic produced

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


How does aspirin interact with COX enzymes

Covalently binds to serine residue in the COX enzyme


How does aspirin interact with COX

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


What are the main side effects of NSAIDs

1. Stomach pain
renal failure
liver damage


Why is nausea so common with the use of NSAIDs

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


What use does misoprostol have

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


How do NSAIDs affect renal blood flow

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


How do NSAIDs affect the liver

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