Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pmcol 343 > 3.9 Lipid Mediators + Inflammation > Flashcards

3.9 Lipid Mediators + Inflammation Flashcards

1
Q

Why is the lipid mediator system druggable?

A

Mediators aren’t stored, but made to-order/on demand only. Therefore specific enzymes can be targetted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do glucocorticoids affect the lipid mediator system?

A

+annexin 1 = -PLA2 = -lipid mediators

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Lyso-glyceryl-phosphorylcholine is converted to…?

A

Platelet activating factor (PAF)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the effect of PAF on the veins?

A

Dilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the effect of PAF on the lungs?

A

Bronchoconstriction, increased vascular permeability (+fluid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the effects of PAF in the immune response?

A

Chemotaxin– gathers immune cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the 2 types of enzymes affecting AA conversion?

A

Lipooxgenases (LOX) and cyclooxygenases (COX)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the conversion reaction pathway of 5-LOX?

A

AA –> 5-HpETE –> leukotrienes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which LOX makes leukotrienes?

A

5-LOX

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which leukotriene is a chemotaxin?

A

LTB4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The majority of leukotrienes are…?

A

Bronchoconstrictors (increase permeability, more fluid in lungs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the general conversion reaction pathway of COX enzymes?

A

AA –> cyclic endoperoxides –> prostaglandins + TXA2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What type of enzymes generate prostaglandins?

A

COX

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the effects of PGI2/prostacyclin?

A
  1. Vasodilation
  2. Hyperalgesia
  3. Stops platelet aggregation
  4. Bronchodilation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Of the 2 main COX products, ___ is negative and ___ is positive

A

PGI2 = -
TXA2 = +

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the effects of TXA2?

A
  1. Vasoconstriction
  2. Platelet aggregation (thrombotic)
  3. Bronchoconstriction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the notable prostaglandins?

A

PGI2, PGD-Falpha

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Why is PGF2a unique among the prostaglandins?

A

Myometrial contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Most prostaglandins cause…?

A

Vasodilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Which prostaglandins affect platelet aggregation?

A

PGI2 (stops it)
PGD2 (inhibits it)

21
Q

What are the effects of PGD2?

A
  1. -platelet aggregation
  2. Vasodilation
22
Q

What are the effects of PGE2?

A
  1. Vasodilation
  2. Hyperalgesia
23
Q

Which prostaglandins cause hyperalgesia?

A

PGI2 and PGE2

24
Q

Which drugs inhibit COX enzymes?

A
  1. NSAIDs (directly)
  2. Glucocorticoids (-induction)
25
Q

Glucocorticoids ___ COX activity

A

Decrease

26
Q

How do glucocorticoids affect the lipid mediator system?

A
  1. Inhibit PLA2
  2. Decrease COX activity
27
Q

What are eicosanoids?

A

All the lipid mediators derived from AA

28
Q

AA liberation by PLA2 is dependent on…?

A

Ca2+ signalling

29
Q

What is the PLC signalling pathway?

A

Phospholipids –(PLC)–> IP3 + DAG
IP3 = Ca2+ signalling
DAG = PKC signalling

30
Q

How do phospholipids become AA?

A

Phospholipids –(PLD)–> phosphatidic acid –(PLA2)–> AA

31
Q

How can DAG become AA?

A
  1. DAG –(DAG kinase)–> phosphatidic acid –(PLA2)–> AA
  2. DAG –(DAG lipase)–> AA + glycerol
32
Q

What is the role of Ca2+ in lipid mediator signalling?

A

Required to phosphorylate/activate PLA2

33
Q

T/F: PLA2 is activated by dephosphorylation

A

False, opposite

34
Q

COX1 PG synthesis is ____ and COX2 PG synthesis is ___

A

COX1 - constitutive, constant
COX2 - inducible

35
Q

What are the effects of COX1 PG synthesis?

A

Good
1. Stomach protection - mucous, -HCl
2. Platelet aggregation

36
Q

What are the effects of COX2 PG synthesis?

A

Bad
Inflammation and pain

37
Q

T/F: NSAIDs are specific to COX1

A

False, target both isoforms in different degrees

38
Q

Where are LTs produced?

A

Inflammatory cells (WBCs)

39
Q

What are the effects of LTB4?

A
  1. Bronchoconstriction
  2. Chemotaxis
40
Q

What is montelukast?

A

LTB4 antagonist used for asthma

41
Q

T/F: PAF is only effective at high doses

A

False, very potent

42
Q

What are lipocortins?

A

Endogenous inhibitors of PLA2

43
Q

What are the 3 phases of the inflammatory response?

A
  1. Acute (turn on)
  2. Immune (persist)
  3. Chronic (consequences)
44
Q

What are autacoids?

A

Local hormones that act near the site of their synthesis involved in acute inflammation

45
Q

What are the 5 autacoids?

A

Histamine, 5-HT, bradykinin, PGs, LTs

46
Q

What are the effects of the autacoids?

A
  1. Vasodilation
  2. Chemotaxis
  3. Hyperalgesia
47
Q

What are the chronic inflammation mediators?

A

Interleukins and TNFa

48
Q

What is the function of bradykinin on lipid mediator synthesis?

A

Stimulate PLA2

Pmcol 343 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions