Bone Turnover

Question 1

What cell releases rank Ligand?

Answer 1

Osteoblasts

Question 2

What the function of RANK ligand?

Answer 2

Essential for osteoclast formation, activation and survival

Question 3

What is OPG and its role?

Answer 3

Inhibition of Osteoclast formation, function and survival

BINDS to RANK receptor so RANK ligands can’t stimulate osteoclasts

Question 4

What regulates the balance between OPG and RANK?

Answer 4

1) Hormones

2) Cytokines

Question 5

IF unopposed RANK ligands what would be the effect on bone?

Answer 5

Increased bone loss, with more osteoclasts stimulated from lack of OPG

Question 6

What is the effect of increased activity on bone?

Answer 6

Increased activity means higher than customary strains on bone, so end up with bone formation

Question 7

What converts 7-dehydrocholesterol into cholecalciferol?

Answer 7

UV Light

Question 8

What are the DEXA T scores for osteoporosis and osteopenia?

Answer 8

Osteopenia: -1.5 -> -2.5
Osteoporosis: -2.5 or more

Question 9

What 4 risk factors does FRAX use to determine probability of osteoporotic fracture?

Answer 9

1) Family History of parental hip fracture
2) Smoking status
3) Use of Glucocorticosteroids
4) Diagnosis of Rheumatoid Arthritis

Question 10

What compound marks increased bone turnover?

Answer 10

Alkaline Phosphatase