Flashcards in Repair and Regeneration Deck (13):
What is regeneration?
-Damaged tissue returns to normal.
-Regains specialised function
What is repair?
-The damaged cells cannot be replaced, leads to fibrosis and scarring.
-Loss of specialised function.
What are liable cell populations?
Liable cell populations have:
1) high normal turnover
2)Active stem cell population
3)Excellent regenerative capacity
What are stable (quiescent cell populations)?
Stable (quiescent) cell populations have:
1) low turnover
2)Turnover can increase if needed
3) good regenerative capacity
e.g. Liver, renal tubules
What are permanent cell populations?
Permanent cell populations :
1) no turnover
2) minimal / no regenerative capacity
e.g. neurons, muscle cells (however research is being conducted in this area)
How is regeneration controlled?
-PROLIFERATION of stem cells covering of defect (cells at edges of defect can proliferate to COVER the injury)
-Contact INHIBITION (once a layer has formed, proliferation is switched off)
-Controlled by growth factors, cell-cell and cell-matrix interactions.
What does regeneration depend on?
-tissue cell kinetics and architecture
-stem cell survival
What is the role of myofibroblasts in granulation tissue formation?
-Myofibroblasts synthesis collagen and extracellular matrix.
-granulation tissue gains myofibrils
-has contractile ability
What are the possible effects of wound contraction - give examples?
1) Oesophageal peptic strictures - scar tissue contracts to form a narrowing of the oesophagus >>>>swallowing problems
What local factors inhibit healing?
4) foreign bodies
What systemic factors inhibit healing?
6) Vit C deficiency
What type of bone heals fractures