15-Derived Lipids Flashcards
derived lipids includes: 1- 2- 3- etc
1-Eicosanoids (prostaglandins, thromboxane, leukotrienes
2-Steroids (cholesterol and steroid hormones)
3-Lipoproteins
- reflect their origin from polyunsaturated fatty acids with 20 carbons
- they are derived from omega-6 Arachidonic acid
- extremely potent (inflammatory response, hypersensitivity.
Eicosanoids (prostaglandins, thromboxane, leukotrienes
eicosanoids are different than different because :
1- they are produced in …….. amounts in ……….. tissues
2- they act ……. rather than transport in blood
3-they are …….. with a short half-life
1-small, almost all
2- locally
3- not stored
- are carboxylic acids that contain a five-membered ring.
- made in sites of tissue damage where they cause inflammation
- stimulates the formation of a blood clot by causing muscles to contract
Prostaglandins
a prostaglandin called …….. stimulates the formation of a blood clot
Thromboxane
a prostaglandin called …….. has the opposite effect as thromboxane
Prostacyclin
anti-inflammatory drugs that block the action of cyclooxygenase enzymes (COX-1, COX-2)
- inhibits prostaglandin synthesis.
Aspirin, Ibuprofen
- mediators of allergic response and inflammation
- mediators of hypersensitivity reactions such as asthma
Leukotrienes
- the most chemotactic agent
it causes smooth muscle contraction, constrict the bronchiole, increase capillary permeability, activate leukocyte and produce vasoconstriction
LT-B4
- classified as lipids because they are soluble in nonpolar solvents
- they are nonsaponifiable
- four fused ringed structure
Steroids
- most abundant steroid
- essential component of cell membranes and precursor for other steroids like bile salts, sex hormones. vitamin D and the adrenocorticoid hormones
- high levels may indicate atherosclerosis
- from milk, meat, and eggs
- synthesized in the liver
Cholesterol
sources of cholesterol:
1- dietary cholesterol
2- cholesterol synthesized (de novo) by extrahepatic tissues and by the liver itself
what form is plasma cholesterol?
Esterified form (cholesteryl ester)
because cholesteryl ester is more hydrophobic its transported in association with …………… or be solubilized by …..and……. in the bile
Lipoprotein, phospholipids and bile salts
cholesterol functions: (how) 1- cell membranes: ... 2-nerve conduction: ... 3-bile salts and acids:... 4-steroid hormones:... 5-vitamin D3:...
1-has an effect on the fluid state of the membrane
2- has an insulating effect on nerve fibers
3-derived from cholesterol
4- glucocorticoids, androgens, estrogens are from cholesterol
5- derived from cholesterol
