Healing and repair Flashcards
What is repair?
It is when inflammation recedes but scarring remains
What do proteoglycans do?
Form a hydrated gel which resists compressive forces whilst permitting rapid diffusion of nutrients, metabolites, and hormones
What is primary intention wound healing?
Two edges of skin link together
What is secondary intention wound healing?
Two ends of skin cannot reach together.
Longer healing.
Epidermis heals from the bottom up.
What is transcytosis?
A type of transcellular transport in which various macromolecules are transported across the interior of a cell.
Also known as cytopempsis.
What is fibroplasia?
The process of forming fibrous tissue in wound healing.
Fibroblast proliferation and migration.
Production of collagen, proteoglycans, and elastin to re-form the ECM.
What happens in re-epithelialisation?
Upward maturation of keratinocytes/epithelial cells.
Keratinocyte proliferation is inhibited until migration is complete.
What cells produce growth factors to stimulate healing in the epidermis and dermis?
Macrophages, fibroblasts, and
endothelial cells
What do matrix metalloproteinases do?
They help remodel the ECM.
They are inhibited by TIMPs.
What is granulation tissue?
New connective tissue and microscopic blood vessels that form on the surfaces of a wound during the healing process.
How do stellate cells cause liver fibrosis?
Produce collagen that causes the space of Diss to expand.
What are the consequences of myocardial fibrosis?
1) Contractile dysfunction
2) Arrhythmia
3) Myocardial rupture
4) Pericarditis
5) Ventricular aneurysm
6) Papillary muscle dysfunction
What are the cell mediators of ECM regrowth?
Fibroblasts
Macrophages
Inflammatory cells
What are the molecular mediators of ECM regrowth?
TGF-β
Growth factors: PDGF, EGF, HGF, FGF
Inflammatory cytokines: TNF-α, IL-1, IL-6
Matrix metalloproteinases and TIMPs
