Chemical Mediators of Inflammation Flashcards
Examples of pre-formed mediators
Histamine, Serotonin, and some lysosomal enzymes.
Important categories of plasma proteins in inflammation?
Coagulation proteins – Hageman factor, plasmin
Fibrinopeptides (Fibrin Degredation products)
Complement Proteins (C3a, C5a, C3b)
Kinins
Immunoglobulins
Activation of ________ plays a key role in activating most of the other plasma proteins
Hageman Factor
Newly synthesized products in inflammation are usually made by….
Endothelial Cells
Monocytes
Fibroblasts
Clotting/Fibrinolytic System. Pre-formed and Newly synthesized messenger?
Pre – Histamne
New – Prostaglandins
Complement System. Pre-formed and Newly synthesized messenger?
Pre – Serotonin
New – Leukotrienes
Kinin System. Pre-formed and Newly synthesized messenger?
Pre – Lysosomal Enzymes
New – PAF, Cytokines
Where dos fast release histamine come from
lysis of mast cells, basophils
where does serotonin, thromboxane come from
Activation of platelets
How does rapid release Il-1 happen?
Activation of local sentry macrophages
WHy would a mast cell release its histamine?
Trauma/Cold Immunologic Rxn (IgE) C3a, C5a Histamine-releasing factors from neutrophils, monocytes, and platelets Il-1, activation of Toll receptors
Over 90% of serotonin is found…
in enterochromaffin cells in the GI tract
What does Histamine/Serotonin do anyway? Unique activities of them individually?
Vasodilation, increased permeability Stim. of pain/itching Contraction of smooth muscle His -- Axonal reflex of flare response Sero -- Aggregation of platelets
Preformed plasma protein pathways all turned on by activated Hageman Factor?
Fibrin Degradation Products
Anaphylaxis (via complement)
Kinin generation
Clot Formation
Important roles of Plasmin
- Cleaves fibrin into fibrin degradation products
- Cleaves complement components C5 and C3
- Activates Hageman, kininogens, and itself (amplifys the response)
The Kallikrein/Kinin system is important for…
Vascular permeability, contraction of SM, dilation of BV
PAIN
Important details on C5a
Chemotactic for PMNs
Neutrophil degranulation
Superoxide production
Early inflammation release of arachadonic acid leads to formation of…
Prostaglandins and Leukotrienes
Arachadonic Acid exposed to Cyclooxygenase (COX) will form…
Prostaglandins, Prostacyclins, or Thromboxane
Arachadonic Acid exposed to lipoxygenase will form…
Leukotrienes
SRS-A
Arachadonic Acid derivative formed in platelets
TXA2
Arachadonic Acid derivative formed in endothelial cells
PGI2, LTB4
Arachadonic Acid derivative formed in Mast Cells
SRS-A’s/LTC/LTE
PAF
Arachadonic Acid derivative formed in neutrophils
LTB4
Arachadonic Acid derivative formed in Macrophages
PGs
Effects of PGD2 and PGE2
Produce vasodilation, increased vascuar permeability-, bronchoconstriction, hyperalgesia
Effects of PGF2a
Vasodilation, Bronchoconstriction
Effects of Prostacyclin (PGI2)
Vasodilation, Increased vascular permeability, inhibited PMNs, Inhibits platelet aggregation
Effects of Thromboxane A2
Vasoconstriction, Bronchoconstriction, Platelet Aggregation
Antagonizes Prostacyclin
What are the Slow Reacting Substances of Anaphylaxis (list the members)
LTC4, LTD4, LTE4
What are the Slow Reacting Substances of Anaphylaxis (conceptually)
Mediators of responses to severe allergy: constriction of smooth muscle (vaso+broncho) and increased vascular permeability (vascular shock)
Effects of LTB4
Primarily from PMNs, mediated their responses
Chemotaxis + Aggregation/Degranulation
Effects of Platelet Activating Factor
Induces platelet aggregation and degranulation
Enhances the release of histamine and serotonin
Increased vascular permeability
Increases leukocyte adhesion, chemotaxis
Effects of Lipoxins
Anti-inflammatory, Blockage of SRS-A receptor, promotes phagocytosis and cellular killing
Early mediators of platelet aggregation…
PAF, Thromboxane A2 from mast cells + platelets
Early mediators of vascular permeability…
SRS-As from mast cells, platelets
Middle mediators of Chemotaxis…
LT B4, SRS-A, PAF from Mast Cells and PMNs
Middle mediators of vascular permeability
SRS-A, LTB4 from PMNs
Late mediators of vasodilation, vascular permeability…
SRS-A from PMNs, PGs from Macrophages
What are interleukins?
Cytokines that communicate between different types of leukocytes, particularly mono and lymphs
What is IL-2
T cell growth factor
Receptor induced by Il-1 from macrophages, Il2 production
Which interleukins have systemic effects?
IL1, TNFa, IL6
Primarily PMN chemokine?
IL8
Role of IFNg in inflammation?
from T and NK, induces expression of MHC I and II, activates phagocytes, inhibits TH2, enhances leukocyte-endothelial adherence.
M-CSF is made by ____. Its role is….
Macrophages
promote monocyte precursor growth
G-CSF is made by ____. Its role is…
Mphages. Promote granulocyte prolif.
GM-CSF is made by ______. Its role is…
T cells, Mphages, Fibroblasts, endothelial cells
Promotes granulocyte precursors
TGFbeta is a potent stimulator of….
Fibrinogenesis and Scar Tissue
IL1, TNF, IL6. Where do they come from? What do they do?
From – Mphages + inflam cells
Do – Fever, Acute Phase Proteins, Septic Shock
Il2, Il12. Where do they come from? What do they do?
From - Lymphocytes
Do – Promote lymphocyte proliferation
IFNg. Where do they come from? What do they do?
From – Lymphocytes
Do – MHC/Adhesion Molecule Expression
Activation of mp in granuloma formation
IL8. Where do they come from? What do they do?
From – Activated inflamm. cells
Do – Neutrophil adhesion and migration
MCP-1. Where do they come from? What do they do?
From – Activated Inflamm. cells
Do – Monocyte migration
RANTES, MCP-3. Where do they come from? What do they do?
From – Inflamm. Cells
Do – Macrophages + Mast Cells for eosinophil migration
GM-CSF. Where do they come from? What do they do?
From – Inflam. cell prolif and differentiation
Do – Expression of adhesion molecules, Cytokines
Still even a little shakey on all of this?
Look at the summary on the last page
IL receptors assocaited w/ Jak/Stat
2, 4, 7, 9, 15
Type of mediator seen in minutes? minutes->hours? hours->days? Days->weeks?
Minutes – Preformed
Minutes/Hours – Plasma-Derived
Hours/Days – AA Metabolites
Days/Weeks – Cytokines, ILs, Chemokines, GFs
Difference between Aspirin and NSAIDS
Aspirin – Irreversible Cox inhibition