Acute Inflammation Flashcards
Acute Inflammation
respond/protective changes to maintain intergrity, localised in site of injury
Redness that doesnt cease
Rubor tumor dalor (pain) calor (heat) + loss of function
takes place in microcirculation
Flow (Q) is proportional to r (power of 4)
Poiseuille’s Law
Control flow (fluid flux) across membrane (hydrostatic and colloid osmotic pressures compartments and physical constants)
Starling forces
neutrophil move to endothelial aspect of lumen
Margination
neutrophil attach to endothelial walls
Pavementing
neutrophil squeeze between endothelial cells to ECF
Emigration
Rouleux formation
RBCs aggregration
Effects of exudation
oedema formation = swelling
Vasodilation and Increased Permeability
Increased blood - Increase HP inside - drives fluid pressure - leaks out
= Proteins and fluid leaking out of vessels
Decreased colloid pressure - conc inside lower
Benefits of Acute Inflammation
rapid response to non-specific insult cardinal signs and loss of function transient protection of inflamed area neutrophils destroy organisms and denature antigen for macrophages plasma proteins localise process resolution and return to normal
adhesion molecules appear on endothelial cells
ICAM-1 - help neutrophils stick
P-selectin - interacts with neutrophil surface
Cell surface mediators
Causes vasoconstriction
Preformed in platelets
Released when platelets degranulate in coagulation
5-hydroxytryptamine (serotonin)
Mediators Molecules released from cells
Increase conc of RBC as plasma protein pass between endothelial cells = Increase Viscosity = allows:
Stasis - blood pass slow - allows leucocyte - neutrophil - margination, pavementing, emigration
mobile phagocyte
chemotaxis
adherence
release granules = pus
Neutrophils
Form fibrin and clot exudate
fibrinogen (pp) - coag factor
Blood coag
clots fibrinogen in exudate