Lec 10 Pharm Arachidonic Flashcards
Eicosanoids are products of what process?
oxygenation of polyunsaturated long chain fatty acids
What is the most abundant eicosanoid precursor?
arachidonic acid
What is path of eicosanoid synthesis?
- arachidonic acid is released from membrane phospholipids by phospholipase A2 [PLA2]
- arachidonic acid oxygenated to eicosanoid
What is action of phospholipase A2?
releases arachidonic acid from membrane phospholipids
What are the 4 paths arachidonic acid can take to become eicosanoid?
- Cyclooxygenase [COX]
- Lipoxygenase
- P450 epoxygenase
- isoeicosanoid
Do eicosanoids act as autocrine, paracrine, and/or hormone?
autocrine and paracrine; not hormone b/c short half life
Which prostaglandins/ thromboxanes are vasoconstrictors?
- TXA2
- PGF2
Contraction of smooth muscle is mediated by what molec?
mediated by Ca
Relaxation of smooth muscle is mediated by what molec?
mediated by cAMP
Which prostaglandins/ thromboxanes are vasodilators?
- PGI2
- PGE2
What is mech by which PGI2/PGE2 are vasodilators?
- increase cAMP and decrease intracellular Ca in smooth muscle –> relaxation of smooth muscle
Where is PGI2 synthesized?
smooth muscle and endothelial cells
What type of drug inhibits phospholipase from releasing arachidonic acid?
steroids
What type of drug [s] inhibit cyclooxygenase path?
- aspirin
- indomethacin
- Cox1/Cox2 inhibitors
What is another name for prostacyclin?
prostaglandin I2
What is general action of Cox1 path on GI?
more productive for GI
- increase mucous; decrease acid
regulate body temp
Which Cox path is inducible?
Cox2 is inducible –> from pro inflammatory mediators