Cell Response To Injury 2 - Acute Inflammation Flashcards
(27 cards)
Definition of inflammation
• A response of vascularized tissues to infections and tissue damage that brings cells and molecules of host defence from the circulation to the sites where they are needed, to eliminate the offending agents.
• The complex biological response of tissues to harmful stimuli and is a protective response involving blood vessels, immune cells and molecular mediators.
Why study inflammation?
Dental caries
Pulpitis
Periodontal disease
Dental cysts
What are the 2 types of inflammation?
Acute and chronic
What is the purpose of acute inflammation?
(3)
Sequence of events in acute inflammation?
Examples of stimulus
What is the earliest event in acute inflammation?
Increase in capillary size - vasodilation
What are the four factors that cause vasodilation during the vascular events of acute inflammation?
What does vasodilation lead to?
Histamine
Prostaglandins
Platelet activating factor
Kinins
It leads to a increase in flow rate of blood through the vessel which leads to heat and redness at the site of injury
What are the two main events of acute inflammation?
1)Vascular
2)Cellular
After vasodilation, what happens in the vascular events of acute inflammation?
What is increased permeability due to?
What is exudate?
Increased vascular permeability
Permeability is due to:
Histamine
Leukotriene
Platelet activating factor
Kinins
Exudation is the process of flow of fluid and plasma proteins out into the extra vascular space
Exudate is the fluid that collects
(Increased permeability is due to the result of gaps between endothelial cells opening up and therefore leakage of fluid and plasma proteins in extra vascular space.)
What are the 2 vascular events in acute inflammation
1) vasodilation
2) increase in vascular permeability
Cellular events - what key cell?
Neutrophils - recognised by multinucleated
What is margination
Neutrophils are found towards edges at sites of inflammation
What is expressed on neutrophils
L selectin
(a receptor)
What upregulates (increases?) L selectin?
TNF
IL-1
What happens after neutrophils detect ligands on endothelial cells?
Neutrophil rolling
(On P selectin)
Amend these notes from celllular events
What stops neutrophil rolling
Integrin
What are the three types of exudate
1) serous
2) fibrinous
3) purulent
Chemotaxis - neutrophils
Chemotaxis: p
• Bacterial products
• Chemokines
• C5a
• Leukotriene B4
At site of inflammation what do neutrophils do
Remove bacteria and necrotic debris by phagocytosis
Phagocytosis steps
- Adherence & ingestion
- Phagosome formation
- Phagolysosome
- Digestion
- Residual body
- Discharge
Cardinal signs of inflammation
Heat
Redness
Swelling
Pain
Loss of function
