what is inflammation?
reaction of living vascularised tissue to sub-lethal cellular injury
what is the function of inflammation?
to remove the cause of injury and initiate repair
what are the 2 types of inflammation?
- acute (hours/days)
- chronic (weeks/months)
what harmful effect can inflammation have?
can cause tissue destruction
what causes inflammation?
- infection
- foreign body
- mechanical trauma
- chemical injury
- radiation injury
what are the inflammatory reaction components?
- cells
- ECM
- soluble factors
what are the cells involved in inflammation?
- neutrophils
- macrophages
- lymphocytes
- eosinophils
- mast cells
what are the ECM components involved in inflammation?
- collagen
- proteoglycans
- fibroblasts
what are the soluble factors involved in inflammation?
- antibodies
- cytokines
- complement system
- coagulation system
what are the features and functions of neutrophils?
- contain cytoplasmic granules
- phagocytosis
- degranulation
what are the features and functions of monocytes/macrophages?
- monocytes in blood give rise to macrophages in tissue
- phagocytosis
- control many other inflammatory cells
- release cytokines
what are the features and functions of eosinophils?
- seen in allergic and parasitic causes of inflammation
what are the features and functions of mast cells?
seen in allergic diseases
what are the LOCAL clinical features of acute inflammation?
- calor = heat
- tumour = swelling (oedema)
- rubor = redness
- dolor = pain
- loss of function
what is calor caused by?
histamine mediated vasodilation
what is tumour caused by?
histamine mediated increase in permeability of vessels leading to increased interstitial fluid (oedema)
what is rubor caused by?
slow blood flow resulting in redness
what is loss of function caused by?
swelling and pain
what is histamine?
- vasoactive amine
- produced by mast cells
- packaged into granules inside mast cells and binding of antigen to IgE on the surface of mast cells causes degranulation
- leads to vasodilation and increased vascular permeability
name 4 important mediators other than histamine
- prostaglandins
- chemokines
- complement
- cytokines (interleukins, TNF)
what can target the inflammatory mediator histamine?
anti-histamines
what can target the inflammatory mediator prostaglandin?
aspirin
what can target the inflammatory mediators IL-1 and TNF?
anti-TNF antibodies
what is colloid osmotic pressure?
a form of osmotic pressure exerted by proteins in a blood vessel’s plasma that usually tends to pull water into the circulatory system
