Tissue Repair Flashcards
What three tissues regenerate in response to injury?
The damaged tissue, vascular endothelial tissue, and fibroblast/ECM.
Labile tissues are tissues that are ________.
constantly dividing and turning over (e.g., skin, GI tract)
Colon tissue has a ___________.
“test-tube like” appearance
Stabile tissues are tissues that ___________.
are not constantly dividing, but are capable of dividing in response to injury (e.g., parenchyma of most solid organs)
Permanent tissues are _______.
fully differentiated–not able to proliferate (e.g., brain and cardiac muscle)
Most adult tissues are replaced by _________ when they die.
adult stem cells
Growth factors can be released by _______ in response to tissue injury
macrophages and lymphocytes (as well as parenchymal cells)
What are the major components of interstitial ECM?
Fibrillar and non-fibrillar collagens, fibronectin, elastin, proteoglycans, hyaluronate
What are the major components of basement membrane ECM?
Amorphous non-fibrillar type IV collagen and laminin
The liver has a ________ regenerative capacity; as much as ______ can be removed from a donor.
robust; 40% to 60%
List the steps of scar formation.
Angiogenesis, migration and proliferation of fibroblast cells, and maturation/reorganization of fibrous tissue
What three cytokines are important in fibrinogenesis?
PDGF, FGF-2, and TGF-beta (the most important) released by alternatively activated macrophages
The most important kind of ECM-modifying substance is _______.
matrix-metallo-proteases (MMPs)
List three factors that limit tissue repair.
- nutritional deficiency
- metabolic syndromes (e.g., diabetes, gluccocorticoids)
- venous drainage impairment
Local things that affect tissue repair include _______.
- persistence of original insult
- new insult (such as infection)
- foreign material
- size and location of injury
The difference between a hypertrophic scar and a keloid is that _____.
hypertrophic scars regress (eventually)
Anything that crosses a joint space is called a ________.
contracture
First intention healing is ________.
mainly epithelial
Second intention healing is _________.
more complex and involves some scar formation
What two cells deposit collagen?
Fibroblasts and myofibroblasts
What cell types proliferate during repair?
Fibroblasts, vascular endothelial cells, and remnants of the injured tissue
