Physiology + Pharmacology of Inflammation + Autoimmunity Flashcards
Describe inflammation
Protective response
Response of blood vessels + leukocytes
Describe acute inflammation
Rapid
Presence of leukocytes
Exudation of fluids + plasma proteins
Describe chronic inflammation
Longer
Presence of lymphocytes + macrophages
Fibrosis + tissue disruption
What happens in acute inflammation?
Vasodilation = mediators - eg. histamine binds
Increased blood flow
Increases permeability of microvasculature
Increase viscosity of blood
Stasis = slows moving RBCs = fluid leaves capillary
Neutrophil accumulation
What are the stimuli for acute inflammation?
Infections
Tissue necrosis
Foreign bodies
Immune reactions
How do leukocytes adhere to endothelium?
Leukocytes redistribute along endothelium
Detach + adhere = mediated by selectins
Firmly adhered = mediated by integrins
Transmigration
Emigrate to site of tissue, followed by chemoattractant
How do leukocytes respond?
(Phagocytosis)
Particle bound to phagocyte receptor
Plasma membrane form vesicle
Phagosome fuses with lysosomal granule
ROS + NO + lysosomal enzymes = kill + degrade
Describe cell-derived mediators
Produced locally
Pre-accumulated or synthesised de novo
Describe plasma protein-derived mediators
Produced in liver
Circulate in plasma as inactive precursors
What mediators does anti-inflammatories target?
Prostaglandins
Leukotrienes
Describe prostaglandin + leukotrienes
Phospholipase release arachidonic acid COX-1 + COX-2 convert AA in prostaglandin
OPTION 1: Thromboxane synthetase convert PGH2 to thromboxane
OPTION 2: prostacyclin synthetase convert PGH2 to prostacyclin
What are COX-1/2 inhibitors?
Aspirin
Ibuprofen
Paracetamol
What is the anti-inflammatory effect of COX-1/2 inhibitors?
Block PGs production = reduce vasodilation
What is analgesic effect of COX-1/2 inhibitors?
Reduce pain by inhibiting PGs production
What is anti-pyretic effect COX-1/2 inhibitors?
Lower higher temperature