Exam 2: Healing and Repair Flashcards
The process by which lost or necrotic cells are replaced by vital cells
Repair
What are the 2 types of repair?
- Parenchymal regeneration
2. Fibrosis
repair of injured tissue by replacement of damaged tissue with cells of identical type, sometimes leaving no residual trace of the previous injury
Parenchymal regeneration
Parenchymal regeneration can only occur if what 2 things have been met?
- tissue has capability to regenerate
2. CT framework is maintained
Replacement by fibrous CT or fibroplasia
Fibrosis
Repair by fibrosis results in an inc in ____ within tissues
Collagen
The cells of the body are divided into 3 groups based on their regenerative capability
- Labile cells
- Stable/ quiescent cells
- Nondividing/permanent cells
Cells that continue to proliferate throughout life, continuously replacing destroyed cells
Labile cells
List some examples of labile cells:
- surface eptithelia
- lining mucosa
- Lining of GIT
- Urinary tract
These cells usually demonstrate a low normal level of replication. however can undergo rapid division in response to stimuli
Stable/quiescent cells
List some examples of stable cells
- epithelial cells of liver, kidney, lung, pancrease
- smooth m. cells
- Fibroblasts
- Bascular endothelial cells
These cells have left the cell cycle and cannot undergo mitotic division in postnatal life
Nondividing/ permanent cells
List some examples of Nondividing/ permanent cells?
- neurons
2. cardiac m. cells
Repair by CT?
fibrosis
What are the 4 components for the process of fibrosis?
- migration and proliferation
- deposition of ECM
- Formation of new blood vessels
- Maturation and organization of the scar
Factors favoring fibrosis over regeneration
- severe and prolonged tissue injury
- Loss of tissue framework
- large amts. of exudate
- lack of renewable cell pops.
These cells usually demonstrate a low normal level of replication
Stable/Quiescent cells
Examples of Stable cells
- Epithelial cells of liver, kidney, lung, pancrease
- Smooth m.
- Fibroblasts
- Vascular endothelial cells
What are the 2 major consequences of Fibrosis?
- Loss of functional parenchymal tissue
2. Alteration of physical properties of tissue
T/F. the process of repair begins late in inflammation
F. Early
What is the hallmark of healing, and forms by 3-5 days?
Granulation tissue
What are the 4 Zones of granulation tissue?
- Zone of necrotic debris and Fibrin
- Zone of macrophages + growing capillaries
- Zone of proliferating capillaries and fibroblasts
- Zone of mature fibrous CT
Which zone of granulation tissue represents the oldest portion of the healing process
Zone of mature fibrosis and CT
The process by which the amt. of collagen deposition is inc.
Maturation of Granulation tissue
Granulomas and granulomatous inflammation corresponds to acute/chronic inflam.
Chronic
______ is part of the repair process. Granulation tissue is characterized by large amounts of fibrous CT and neovascularization
Granulation tissue
A process including CT replacement and regeneration by which restoration of tissue continuity is achieved
Wound healing
What are the 2 types of Healing?
- Healing by first intention
2. healing by second intention
What is healing by first intention
When there is little exudate and when tissue elements are closely approximated
Ex: surgical wounds
What is healing by second intention?
Occurs when edges of wounds are widely separated
T/F. the kidney has limited regenerative capability
T
how does healing happen in the liver
Parenchymal regen.
