Flashcards in Tissue Repair Deck (21)
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 _______.
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 ________.
First intention healing is ________.
Second intention healing is _________.
more complex and involves some scar formation
What two cells deposit collagen?
Fibroblasts and myofibroblasts