Eicosoniods Flashcards
What are the 3 types of Eicosanoids?
- Prostaglandins (PG)
- Thromboxanes (TX)
- Leukotrienes (LT)
T or F: Eicosanoids are produced by almost all cells
True
What is one of the biggest processes controlled by Eicosanoids?
Inflammation
What Eicosanoids are involved in control of bleeding?
- what are the effects?
- Thormboxane made by PLATLETES enhance aggregation
2. PGE2 and PGI2 (FROM ENDOTHELIAL CELLS) inhbit platelet aggreaction
T or F: different cell types have different enzymes which results in their response being very cell specific
True
What are some of the functions of Eicosanoids?
- Inflammatory Response
- Regulate Smooth muscle contraction
- Increase Water and Sodium Excretion
- BP regulation
- Constrict and Dilate BVs
- Brochoconstriction and dilation
What are Eicosanoids Derived from?
20C fatty acids
Arachidonic Acid*
T or F: Archidonic acid can be made by the human body
True
How many unsaturations are their in Eicosanoids?
4
How many carbons are in Linoleate?
18C
How do we get precursors for Arachidoninc acid?
- We ingest them
What must act on Linoleate to turn it into arachidonic acid?
- Elongase
2. Desaturase
What does the presence of glucocorticoids do to production of Eicosanoids?
- Inhibits release of Arachidonic Acid from its
What are the two general precusors of Arachidonate?
- What enzymes work to turn these into arachidonic acid?
- Phospholipids (Phospholipase A2)
2. Diacylglycerols (DAG Lipase)
What is the common precursor to prostaglandins and thromboxanes?
Prostaglandin H2 (PGH2)
What are the 2 activites of Prostaglandin Synthase?
- Cyclooxygenase
- Peroxidase
From what part of the cell membrane are precursor lipids of Arachidonic Acids released?
- Inner Leaflet of Cell Membrane
What can we derive Arachidonic acid from?
- Essential Fatty Acids
- Omega-6
- Omega-3
When signal tells the cell to make Eicosanoids?
- Cytokine, hormone signals
What are the 3 different pathways that Arachidonic acid can go down initially?
- Cyclooxygenase
- Lipooxygenase
- Cytochrome P450
T or F: after released Eicosanoids bind Cell Surface Receptors
True
What Eicosanoids work through the Adenylate Cyclase, cAMP, PKA pathway?
- PGE
- PGD
- PGI
What eicosanoids increaes Ca2+ in the cytosol?
- PGF2
- Thromboxane A2 (TXA2)
How long is the lifespan of an Eicosanoid?
- A few seconds to minutes (very short)
***Means they must act at a short distance from the cell that made them