Collagen & Bones Flashcards
How is vitamin C formed?
Hydroxylation of proline & lysine during collagen synthesis
What happens during collagen synthesis?
Lysyl oxidase cross links collagen
What does lysyl oxidase need as a cofactor?
Copper
What is the 3 AA sequence in collagen?
Glycine- (proline) - (lysine)
Lysine –> crosslinking
What is present in collagen but is not elastin?
hydroxylysine
What is only found in collagen & reticular fibers?
Tropocollagen
What does elastin have?
Glycine, alanine, proline, hydroxlyproline and tropoelastin
What is not needed for synthesis of collagen?
Vitamin K & Folic acid
What is responsible for calcium regulation?
PARAthyroid hormone (increases serum calcium)
What’s the main role of calcitonin?
bone resoprtion
Osteoclasts become?
Monocytes
What is not in periosteum?
Osteocytes
What cytokines are found in osteolcastic bone?
IL-1, IL6, PGE2, TNF-alpha, MMPS
What are housed in Howships’s Lacunae?
Osteoclasts
resoprtion
What is first resrobed by osteoclasts?
Trabecular bones –> lacuna (deposit compact bone in ti later)
what is a thin layer of c.t that lines the surface of bony tissues that form the medullary cavity of long bones?
Endosteum
What type of bone do you see after 2-3 years at the site of injury
Compact bone
What is not found in the compact bone?
Fibroblasts
What’s the formula of most common salt in the bone?
HA Ca10(PO4)6(OH)2
What is Vitamin D called in
Children?
Adults?
Children: rickets
adults: osteomalacia
Vitamin D
Where does 25 hydroxycholecalciferol gets converted to 1,25 dihydroxycalciferol?
Kidney
where do you get vitamin D from?
Skin, liver, kidney
