Lecture 3- Acute Inflammation Flashcards
Inflammation types?
Acute and chronic
What is inflammation?
Response of living tissue to injury
What does it mean to say acute inflammation is innate and stereotyped?
It is the same very time
Adaptive immune system is tailored to toxic insult
What is exudate?
Mass of cells and fluid that leaks out of vessel during inflammation
What causes inflammation?
Anything that damages body including trauma, hypersensitivity and microbes
What are the 5 clinical signs?
Rubor= redness
Tubor= swelling
Dolor= pain
Calor= heat
Loss of function
What changes occur in blood vessels during inflammation?
Vascular- changes in blood flow and movement of fluid into tissue
Cellular- movement of inflammatory cells into tissue
How doe
S inflammation change blood flow?
Initial transient vasoconstriction
Vasodilation
Permeability increased and oedema
Red cell stasis as blood more viscous in vessels
What changes in vessels and surrounding tissue does inflammation cause?
Changes in blood flow
Movement of fluid into tissue
Infiltration of inflammatory cells into tissue
How does movement of fluid into tissues work in inflammation?
Governed by Starlings law.
Hydrostatic pressure is greater than oncotic pressure. Vasodilation and increased vessel permeability also help.
Results in oedema and tumor.
Fluid movement out of vessel leads to increased blood viscosity and red cell stasis.
This stasis helps later with tissue infiltration by inflammatory cells
What are the types of interstitial fluid?
Exudates and transudate.
Exudate formed in acute inflammation. Protein rich, increased vascular permeability
Transudate occurs in heart failure, liver failure etc where blood pools or lacks proteins etc. Blood pooling increases hydrostatic pressure forcing blood out of vessel. Decreased protein content moves oncotic pressure outside vessel and draws fluid out
How is vascular permeability increased?
Histamine causes endothelial contraction and gaps.
Direct injury eg toxic burn
Leukocyte injury
Primary WBC involved in inflammation?
Neutrophil
How do neutrophils leave vessel and enter tissue?
Increased blood viscosity reduces flow. Neutrophils slow down and line up at the edge of vessel wall known as margination, then roll, then adhere and then undergo emigration through vessel wall.
Chemotaxis leads them to pathogens
What molecules increased in inflammation help neutrophils emigrate into tissues?
Selectins on the endothelial surface and integrins on the surface of the neutrophils
How do neutrophils move through the interstitium?
Chemotaxis through chemoattractants
How does oedema limit damage?
Dilutes toxins
Increases lymphatic drainage and toxin removal. Delivers antigens to lymph nodes for adaptive immune response
Brings plasma proteins to injury site (inflammatory mediators and immunoglobulin)
Brings fibrin which creates mesh (pale yellow stuff indicates healing)