Eicosanoids

eicosanoids are not hormones but are instead…

local mediators

eicosanoids are produced and released …

locally

name the pro inflammatory eicosanoids

prostaglandins, leukotrienes, thromboxanes and eoxins

name the anti inflammatory / pro resolving eicosanoids

lipoxins and resolvins

what FA is the precursos for arachidonic acid?

linoleic acid

is linoleic acid an omega 3 or omega 6 acid?

omega 6

is linolenic acid an omega 3 or omega 6 acid?

omega 3

do omega 6 metabolites tend to be pro or anti inflammatory?

pro

do omega 3 metabolites tend to be pro or anti inflammatory?

anti

which group of eicosanoids is derived from omega 3 FAs?

resolvins

what are the two omega 3 FAs resolvins are derived from? (abbreviations)

EPA and DHA

prostaglandin synthase has which two activities

COX and POX

what does COX stand for?

cyclooxygenase

what does POX stand for?

peroxidase

what does LOX stand for?

lipoxygenase

which enzyme releases A2 from phospholipids?

PLA2

which enzyme releases A2 from diacylglycerols?

DG lipase

which COX is continuously present and active in most tissues?

COX1

which COX is inducible?

COX2

what inhibits PLA2?

corticosteroids

what inhibits COX 1 and 2?

NSAIDs

what inhibits COX2 only?

corticosteroids

what does the COX activity of prostaglandin synthase produce?

PGG2

the POX activity of prostaglandin synthase converts PGG2 to what?

PGH2

usually when COX1 is on which two types of prostaglandins are produced?

PGI2 and PGE2

usually when COX2 is on which prostaglandin and thromboxane are produced?

PGF2a and TXA2

three functions of PGI2

vasodilation, smooth muscle relaxation and inhibition of platelet aggregation

two functions of PGE2

vasodilation and smooth muscle relaxation

PGI2 and PGE2 allow blood flow to which parts of the body?

GI tract and kidneys

two functions of thromboxanes (TXA2)

vasoconstriction and platelet aggregation

LOX produces what acid

HPETE

which enzyme produces 5-HPETE from A2?

5 LOX

which leukotriene is produced from 5-HPETE and acts as a precursor to a lot of other leukotrienes?

LTA4

LTA4 acts as a precursor to which other leukotrienes?

LTB4, LTC4, LTD4 and LTE4

two functions of PGF2a?

vasoconstriction and smooth muscle contraction

general functions of leukotrienes?

bronchoconstriction, vasoconstriction and chemotactic agents for leukocytes

general functions of eoxins

allergic inflammation and asthma

which cells produce eoxins

eosinophils and mast cells

general functions of lipoxins

inhibit neutrophil recruitment and promote resolution of inflammation

general function of resolvins

actively drive resolution of inflammation

eoxins are produced through which enzyme pathway?

15LOX1 pathway

lipoxins are produced through coordinated actions of…?

multiple LOX enzymes

which two types of enzymes make resolvins?

COX and LOX

which enzyme synthesises PGI2 from PGH2?

prostacyclin synthase

which enzyme synthesises PGE2 from PGH2?

PGE synthase

which enzyme synthesises PGF2a from PGH2?

PGF synthase

which enzyme synthesises TXA2 from PGH2?

thromboxane synthase

which drug inhibits 5LOX

zileuton

which two drugs act as leukotriene receptor antagonists? (they block LT receptors)

montelukast and zafirlukast