Card Set Information
Overview of inflammation and selected aspects of wound healing
what 3 molecules mediate fever?
IL-1, TNF, PGE2
heat, redness and swelling during inflammation are caused by what?
changes in vascularity
what vascular changes occur during acute inflammation?
vasodilation and increased vascular permeability
vasodilation is mediated by what molecules?
endothelial derived NO to induce vascular smooth muscle relaxation and mast cell release of histamine
vasodilation is maintained by what class of molecules?
what results from increased vascular permeability?
movement of fluid out of vasculature, blood becomes more concentrated and flow slows (stasis)
tissue and endothelial cell damage is marked by what 3 types of exudate?
fibrinous, purulent, sanguineous
purulent exudate contains mostly what type of cell?
define endothelial cell contraction
formation of intercellular gaps due to reversible contraction lasting for 15-30 minutes
endothelial cell contraction is mediated by what molecules late and early?
early: histamine, bradykinin. later: leukotrienes and PAF. C3a and C5a lead to edema
explain endothelial cell retraction
restructuring of cytoskeleton proteins that takes 4-8 hours to develop and lasts for 24 hours or more.
endothelial cell retraction is mediated by what molecules?
IL-1, TNF, IFN-g
activated endothelials are characterized by what?
production of PGI
and NO, contraction, rearrangement of cytoskeletal proteins leading to retraction, increased expression of adhesions, synth and release of inflammatory mediators.
what is the sequence of leukocyte extravasation?
margination, rolling, adhesion, emigration, chemotaxis
rolling and adhesion are mediated by what molecules?
rolling: selectins, adhesion: integrins
transmigration of cells through the vessel wall
diapedesis is mediated by what molecule?
Two potent chemotactic molecules are?
(remember PAF helps in contraction)
activation of leukocytes is characterized by what 5 factors?
leukotrienes and prostaglandins, degranulation/release of lysosomal enzymes, ROS, cytokines, cell adhesion molecules
what cell is the hallmark of acute inflammation?
neutrophils (accumulate within 6-24 hrs)
diffuse inflammation of connective tissue with severe inflammation of dermal and subcutaneous layers of the skin. edema
localized area of liquefactive necrosis
erosion of an epithelial surface exposing underlying connective tissue
name 3 reasons for chronic inflammation
persistent infections, prolonged exposure to toxic agent, immune-mediated inflammatory disease
describe granulomatous inflammation
delayed type-IV hypersensitivity, caseous necrosis, collar of mononuclear cells surrounding aggregated epithelioid histiocytes. heals by fibrosis
list 4 diseases characterized by granulomatous inflammation
bacterial TB, parasitic toxoplasmosis, fungal histoplasmosis/mycosis, inorganic silicosis or inert foreign material
source and function of histamine?
mast cells, vasodilation and increased vascular permeability
Function of bradykinin?
increase vascular permeability, pain
Source/function of NO
endothelials, vasodilation and tissue damage
source/function of prostaglandins
membrane phospholipids, vasodilation, pain, fever
source/function of leukotrienes
membrane phospholipids, increase vascular permeability, vascoconstriction, bronchoconstriction
source/function of leukotriene B4
leukocyte, leukocyte activation, chemotaxis
source/function of PAF
leukocytes and endothelials; increase vascular permeability and chemotactic
source/function of cytokines (IL-1, TNF)
macrophage, endothelials; endothelial and leukocyte activation, fever
function of C5a and C3a?
increase vascular permeability
what molecules function as vasodilators?
histamine, NO, prostaglandins
what molecules serve to increase vascular permeability
histamine, bradykinin, leukotrienes, PAF, C3a, C5a
how do NSAIDs work to relieve inflammation?
by blocking cyclo-oxygenase activity
how do steroids relieve inflammation
by inhibiting the release of arachidonic acid
thromboxane A2 does what?
vasoconstriction, promotes platelet aggregation
what works in opposition to thromboxane A2
prostacyclin which inhibits platelet aggregation