acute inflammation Flashcards
(23 cards)
what is acute inflammation?
response of living tissue to infection/damage, develops quickly, initiation for innate immunity
what are the 3 main processes involved
vascular dilation, increased vascular permeability, neutrophil activation and migration
what are the 4 main causes of acute inflammation?
microbial infection, physical agents, irritant and corrosive chemicals, tissue necrosis
what are the consequences of acute inflammation?
redness, heat, swelling, pain, loss of function
what is amplification?
recruitment and activation of innate immune cells via chemokine/cytokine activity and vascular dilation
describe vascular dilation
small b.v adjacent to site of damage become dilated, endothelial cells swell and retract, exudation-vessels become leaky and allow passage of small moelcules, endothelial cells activated to promote immune cells passage to damaged tissues
what is oedema?
excess of watery fluid collecting in the cavities or tissues of the body, increased blood and lymph provides; fluids, salts, glucose,O2, complement proteins and antibodies, fibrin
name 5 chemical mediators?
histamine, bradykinin, leukotrienes, serotonin, prostaglandins
name 2 protein mediators
cytokines, chemokines
what is histamine?
product of breakdown of aa histidine, stored in granules of immune cells such as mast cells, degranulation releases histamine- neurotransmitter causes itching, vascular dilation
what are prostaglandins?
produced by macrophages and neutrophils (with leukotrienes) product of fatty acid metabolism, cause vascular dilation
what are the 5 roles of prostaglandins in acute inflammation?
vascular dilation, reg. cell recruitment reg. cytokine prod. act on nerve fibres-pain involved in tissue remodelling
what enzyme regulates prostaglandins?
cyclo-oxygenase
what are the 4 plasma factors?
complement,
the kinin system,
coagulation,
fibrinolytic system
what is the kinin system?
kallikrein is generated by Hageman factor, neutrophils also engage, kallikrein converts kininogens to kinins
what are the 3 pathways in the coagulation system?
intrinsic- activated by blood contact with sub-endothelial ct
extrinsic-damaged bv allows factor to leave vessel and encounter tissue factor
common-prod. thrombin prod. fibrin (clot)
what is the fibrinolytic system?
results in activation of plasmin, kallikrein and Hageman factor both play role in conversion, involved in breakdown of blood clots, prevents excess clotting in health, activated complement, indirect role as fibrin degradation
why is the balance between coagulation/fibrinolytic system essential?
it is haemostasis- to stop the flow of blood
what are 3 congenital coagulation disorders?
von Willebrand disease,
haemophilia A
haemophilia B
what are 2 acquired coagulation disorders?
warfarin
heparin
what is suppuration?
the formation of pus usually arising from an infection with pyogenic bacteria- abcess
describe suppuration
neutrophil infiltration- encapsulate pathogens then die become pus, once accumulated pus surrounded by a pyogenic membrane
what are the requirements for complete resolution after acute inflammation
minimal cell death and tissue damage,
occurrence in tissues with regenerative capacity,
rapid elimination of causative agent,
rapid removal of fluid and debris by vascular/lymphatic drainage
