collagen Flashcards
What type of tension do type I and II collagen resist?
- type I- tension
2. Type II- tension and compression
What are examples of proteglycans?
- GAG- glycosaminoglycan
2. hyaluanate- proteglycan monemer + hylauronic acid
What is the primary function of proteglycans?
imbibition of the collagen matrix to allow for increased tissue mobility because the collagen tropocollagen is inelastic
How does static stretching of collagen effect tissue tolerances?
It decreases it for a given amount of time based on the amount of deformity
What role to type C free nerve endings play in the collagen healing process?
- .they are left behind in the scar as the capillaries are destroyed by the pressure of the condensing scar
- consequently excessive scaring can become painful
How are mechanical forces transferred to the fibroblast?
Integrens are the primary mechanism for transferring mechanical energy to the cell
What cell is predominately active during the inflammatory stage of healing and what are they doing?
macrophages
- destry cellular debris
- synthesize and secrete fibronectin to attract fibroblasts into the area
what causes primary degeneration of tissue following immobilization?
loss of hyaluronic acid and GAG due to inadequate stimulation of fibroblastic for production of proteoglycans
What treatment activities help reduce muscle tone?
- manual techniques for inhibition of target tissue
- removal of chemical stimulants of type IVs
- repeative painfree ROM
How should ice be dosed in acute injury?
frequently applied every 10-15 minutes
how does tissue healing effect muscle tone?
inhibits muscle tone
How many types of collagen have been identified in the human body and how are they differentiated?
19 types
-they are distinguished by the types and sequencing of their amino acids
What cells are primarily responsible for synthesizing type I collagen?
- fibroblasts
- osteoblasts
- odontoblasts
What cells are primarily responsible for synthesizing type II collagen?
chondroblasts
What cells are primarily responsible for synthesizing type III collagen?
- fibroblasts
- smooth muscle cells
- schwan cells
- hepatocytes
- mesenchymal precursor cells
Where do you tend to find type II collagen
- hyaline cartilage
- elastic cartilage
- vertebral discs
Where do you tend to find type III collagen?
bone, skin, smooth muscle, arteries, uterus, liver, spleen, kidney, lung, tendong, periosteum , endoneurium
What are the functions of type III collagen?
- structural maintenance in expandable organs
- wound healing
- mediating the attachements of tendon, ligaments, and periosteum to bone cortex
- first type of collagen produced in wound healing later replaced by type I
Describe the collagen tissue formation process?
- fibroblasts manufacture procollagen in endoplasmic reticulum
- three procollagen chains form into a triple helix
- triple helix transported out of IR and end components are removed to form tropocollagen
- tropocollagen binds to old collagen via hydorxylysine link with weak ionic bonds
- tropcollagen aligns itself side to side and end to end to form microfibrils
- microfibrils are bundled to form fascicles bundles in with crimped lines
How do the tropocollagen bonds change over time as they become collagen>
- the new hydroxy-lysine links formed by one lysine amino acid attaching to an OH molecule by an ionic bond
- after about 6 months the ionic bond is replaced by a covalent bond (they share an electron) and you can no longer break the bond by gross deformity
What solid structures make up the ground substance or ECM of tendons, ligaments, and articular cartilage?
- glycoproteins
- plasma proteins
- proteglycans
- collagen
What inputs are required for scar tissue formation?
- macrophages
- prostaglandins
- oxygen
What are the cellular events for over production of scar tissue?
1.during inflammation traumatize cells release neurotransmitters, histamine, bradykinins, prostaglandin E
2macrophages in the presence of oxygen and protaglandin E will increase in number
3.increased macrophages bring in more fibroblasts for over production of collagen
What are the chemical and cellular mediators of the different stages of tissue healing?
- inflammation-histamine, bradykinin, prostaglandin E, Fiborgen, leucocytes
- fiborblasitic: capillaries, macrophages, fibroblasts
- remodeling: covalent cross linking, colagenase, MTLS
What neural tissue is left behind as the scar tissue is condensed?
Type IV C free nerve endings
When does scar tissue end shrinkage and covalent bonding occur?
6-12 months
How long does it take for ligament and tendons to close in after trauma
3-5 weeks
When does fibroblast in growth occur after trauma?
1-3 days
When does serofibrin appear at the wound site>
within minutes