Inflammation and Healing Flashcards
What is inflammation/inflammatory response?
The bodies non specific response to tissue injury.
Response is a normal, protective mechanism.
Localise and prevent further injury.
Inflammation is not infection, infection may cause inflammation.
What 2 things stimulates inflammation?
Tissue damage
Or
Antigen.
What happens in the inflammatory response?
Damaged cells release chemical mediators into interstitial fluid and blood.
Macrophages & mast cells are present in the tissues; they are triggered by signals sent out when tissue damage occurs in minutes.
What do mast cells release when activated?
They release histamines, cytokines & lipid mediators.
What are the two lipid mediators?
Leukotrienes
Prostaglandins
What do histamines, cytokines and lipid mediators travel around and cause?
Retracting of the endothelial cells in the capillary wall.
Capillaries to dilate.
Increase capillary pressure (hydrostatic pressure)
Capiliaries to become more permeable.
What is the result of when histamines, cytokines and lipid mediators travel around?
Neutrophils squeeze between the gaps and hoover up pathogens
(phagocytosis).
What does extravasation mean?
The leakage of fluids from a vein into the surrounding tissue.
What is the complement system?
It is a family of proteins that become activated during the inflammatory response.
They bind to microbes and attract leukocytes.
They can also drill a hole through the membrane of the microbe.
What are the symptoms of inflammation?
Swelling
Redness
Heat
Pain
Loss of function
Vascularised tissue (veiny)
What is the healing process regarding inflammation?
Its the immediate next step after inflammation.
What are the two main steps to healing?
Regeneration
Repair
What is the regenerative step of healing?
Replacement of original
tissue with functional tissue
of the same type.
Has to be cells that are capable of mitosis.
Which tissues cannot perform mitosis?
Cardiac
Skeletal muscle
Neurons
What is stroma?
It is a type of connective tissue.
What is the repair step of the healing process?
Replacement of the original tissue with scar tissue.
What type of tissue is scar tissue?
Connective tissue.
What is scar tissue made from?
Type 1 and Type 2 collagen.
What are the scars in neural tissues primarily made from and are they functional?
Non functional
Made up from astrocytes.
What are the 3 STAGES of repair in bone?
The vessels break
A clot forms
Macrophages flood the area and secrete 3 activating substances.
What 3 activating substances do macrophages secrete in the ‘repairing bone’ process?
Fibroblast activator
Angiogenesis factor
Osteogenesis factor
What does the fibroblast activator do?
Secretes the ingredients for collagen.
What does the angiogenesis factor do?
Promotes revascularisation.
What does the osteogenesis factor do?
Increase in osteoblasts.
How long does it take for a clot to form in fracture healing?
Hours since fracture.
How long does it take for inflammation to occur in fracture healing?
1 day - 5 days since fracture.
How long does it take for MSC proliferation to occur in factor healing?
2days-14days since fracture.
How long does it take for angiogenesis to occur in fracture healing?
4 days to 14 days since fracture.
How long does it take for MSC differentiation to occur in fracture healing?
7 days - 21 days since fracture.
How long does it take for bone formation and remodelling to occur in fracture healing?
16days- 6weeks/years since fracture.
What are the 4 complications of the healing process?
Contractures
Strictures
Hypertrophic scars
Keloid scars
What are contractures regarding the healing process?
A complication
A remodelling of scars after healing, problems arise when there is a large area of scarring (think major burns/acid attack scars)
What are strictures regarding the healing process?
A remodelling of scars in “tubular” organs/passages.
Does healing follow the sae process no matter where in the body the damaged cells are?
Yes
