Transcript The clot is replaced by granulation tissue, which restores the

Slide 1
Figure 4.12 Tissue repair of a nonextensive skin wound: regeneration and fibrosis.
Scab
Blood clot in
incised wound
Regenerating epithelium
Regenerated epithelium
Epidermis
Area of
granulation
tissue
ingrowth
Vein
Fibroblast
Macrophage
Migrating white
blood cell
Artery
Inflammatory
chemicals
1 Inflammation sets the stage:
• Severed blood vessels bleed
and inflammatory chemicals
are released.
• Local blood vessels become
more permeable, allowing
white blood cells, fluid, clotting
proteins and other plasma
proteins to seep into the
injured area.
• Clotting occurs; surface dries
and forms a scab.
Copyright © 2010 Pearson Education, Inc.
2
Organization restores the blood 3
supply:
• The clot is replaced by granulation
tissue, which restores the vascular
supply.
• Fibroblasts produce collagen fibers
that bridge the gap.
• Macrophages phagocytize cell debris.
• Surface epithelial cells multiply and
migrate over the granulation tissue.
Fibrosed area
Regeneration and fibrosis
effect permanent repair:
• The fibrosed area matures
and contracts; the epithelium
thickens.
• A fully regenerated epithelium
with an underlying area of
scar tissue results.
Slide 2
Figure 4.12 Tissue repair of a nonextensive skin wound: regeneration and fibrosis.
Scab
Epidermis
Blood clot in
incised wound
Inflammatory
chemicals
Vein
Migrating white
blood cell
Artery
1 Inflammation sets the stage:
• Severed blood vessels bleed and inflammatory chemicals are
released.
• Local blood vessels become more permeable, allowing white
blood cells, fluid, clotting proteins and other plasma proteins
to seep into the injured area.
• Clotting occurs; surface dries and forms a scab.
Copyright © 2010 Pearson Education, Inc.
Figure 4.12 Tissue repair of a nonextensive skin wound: regeneration and fibrosis.
Regenerating
epithelium
Area of
granulation
tissue
ingrowth
Fibroblast
Macrophage
2 Organization restores the blood supply:
• The clot is replaced by granulation tissue, which restores
the vascular supply.
• Fibroblasts produce collagen fibers that bridge the gap.
• Macrophages phagocytize cell debris.
• Surface epithelial cells multiply and migrate over the
granulation tissue.
Copyright © 2010 Pearson Education, Inc.
Slide 3
Figure 4.12 Tissue repair of a nonextensive skin wound: regeneration and fibrosis.
Slide 4
Regenerated
epithelium
Fibrosed
area
3
Regeneration and fibrosis effect permanent repair:
• The fibrosed area matures and contracts; the epithelium
thickens.
• A fully regenerated epithelium with an underlying area of
scar tissue results.
Copyright © 2010 Pearson Education, Inc.
Slide 5
Figure 4.12 Tissue repair of a nonextensive skin wound: regeneration and fibrosis.
Scab
Blood clot in
incised wound
Regenerating epithelium
Regenerated epithelium
Epidermis
Area of
granulation
tissue
ingrowth
Vein
Fibroblast
Macrophage
Migrating white
blood cell
Artery
Inflammatory
chemicals
1 Inflammation sets the stage:
• Severed blood vessels bleed
and inflammatory chemicals
are released.
• Local blood vessels become
more permeable, allowing
white blood cells, fluid, clotting
proteins and other plasma
proteins to seep into the
injured area.
• Clotting occurs; surface dries
and forms a scab.
Copyright © 2010 Pearson Education, Inc.
2
Organization restores the blood 3
supply:
• The clot is replaced by granulation
tissue, which restores the vascular
supply.
• Fibroblasts produce collagen fibers
that bridge the gap.
• Macrophages phagocytize cell debris.
• Surface epithelial cells multiply and
migrate over the granulation tissue.
Fibrosed area
Regeneration and fibrosis
effect permanent repair:
• The fibrosed area matures
and contracts; the epithelium
thickens.
• A fully regenerated epithelium
with an underlying area of
scar tissue results.