UNIT 6 - INFLAMMATION/HEALING Flashcards
Acute inflammation leads to
resolution and healing
chronic inflammation leads to
healing
granuloma leads to
healing and reconstruction
Acute inflammation involves
1) vascular changes
2) action of inflammatory mediators (chemical changes)
3) infiltration of tissue by WBC
Basic responses of acute inflammation
1) local response= vascular and chemical changes
2) Systemic responses = WBC and acute-phase response
classic cardinal signs of acute inflammation
- redness
- heat
- pain
- swelling
What happens in vascular stage
- leukotrienes and prostaglandins come from damaged phospholipids
- arterioles and venules dilate increasing blood flow, resulting in redness and heat
- capillaries more permeable allowing exudate to escape causing swelling and pain
what do WBC’s do
enter injured tissue and:
- destroy infective organisms (phagocytosis)
- remove damaged cells
- release more inflammatory mediators to control inflammation and healing
how do leukocytes enter injured area
- Pavementing = WBC become sticky and stick to endothelial cell membranes
- Emigration = WBC squeeze between endothelial cells (diapedesis)
- Chemotaxis = movement along gradient of chemical attractants released by bateria (get to right place of injury)
Steps of Phagocytosis
- PMN (neutrophil) attaches to bacterium
- PMN engulfs the bacterium
- formation of the phagocytic vacoule
What process do corticosteroids stop?
the production of arachidonic acid
what process do NSAIDS stop?
cyclooxygenase pathway producing prostaglandins
- so reduce pain, decrease vascular permeability, and may inhibit inflammatory response
Arachidonic acid derivatives?
- Lipoxygenase pathway -> leukotrienes
2. Cyclooxygenase pathway -> prostaglandins
What is the complement system
it is another inflammatory mediator in the plasma
- it is a system of proteins produced by the liver
Complement system actions
- cell lysis (MAC)
- increase vascular permeability
- bronchospasm (histamine release)
- neutrophil activation
- chemotaxis
- opsonization (makes bacteria more visible)
- mast cell degranulation
Acute-phase response
it is a systemic manifestation of acute inflammation
- leukocytes release cytokines which affect:
1. the brain: produce fever, fatigue, malaise, shivering etc
2. bone marrow: induces neutrophilia
3. skeletal muscle: muscle catabolism causing amino acid release and muscle wasting
4. liver: induce synthesis of acute phase proteins
serous inflammation
- earliest stage
- watery
eg. blisters, pneumonia
Fibrinous inflammation
- forms strings and becomes sticky and red
- formation of fibrin
- patched broken blood vessels
purulent tracheobronchitis
white/yellow puss
ulcerative inflammation
damage to mucous membrane therefore there is bleeding and an ulcer is formed
Granulomatous inflammation
internal organ
- specialized area of chronic inflammation
Pseudomembranous inflammation
fibrin sheet forms over ulcer
- usually occurs in GI tract
Basic difference between resolution and healin
Healing = replace damaged tissue with another type of tissue (not the same functionality, leads to scarring) Resolution = replace damaged tissue with same type of tissue
Tissues not capable of regeneration and only fibrous (scarring) repair
- brain
- cardiac muscle
- skeletal muscle
