VItamin D

Question 1

What are two main forms of vitamin D?

Answer 1

D2
D3

Question 2

Genomic control of Calcitrol

Answer 2

Activate vitamin D receptor binds vit d response elements and acts as an initiation complex for the RNA pol II -> transcriptional control

Question 3

Non-genomic control of calcitrol

Answer 3

Activates-gated CA2+ channels

Question 4

_______ causes elevation of 1 alpha-hydroxylase and 1,25-(OH)2 D production.

Answer 4

PTH

Question 5

Calcitrol is produced in __________ and ____________ in kidney

Answer 5

Osteoblasts
PCT

Question 6

High calcium/vit D intake

Answer 6

PTH and activate vit D are downregulated
Serum calcium remains normal
Good quality bones formed

Question 7

Low calcium/ vit D intake

Answer 7

PTH is upregulated
Bones are poor quality and liable to fracture

Question 8

Vitamin D reservoir

Answer 8

25 (OH) D

Question 9

Gold standard for 25 OH D

Answer 9

Liquid chromatography / mass spec/ mass spec (LS/MS/MS)

Question 10

What is an LC/MS/MS assay also known as?

Answer 10

Tandem mass spectrometry

Question 11

Evidence from observational studies that ____ 25(OH)D levels associated with a number of diseases e.g. cancer, T2D, CV disease, inflammatory/immune disease, cognitive diseases, mood disorders

Answer 11

Low

Question 12

Meta-analysis / Systematic review of vitamin D supplementation trials have found _____________of an effect on disease occurrence

Answer 12

No evidence

Question 13

Elderly vitamin D supplementation _________ all-cause mortality

Answer 13

Reduces

Question 14

Accurate, high sensitivity, reproducible LC/MS/MS measurement of vitamin D metabolites (25(OH)D2/3, C-3 epimers) essential for routine clinical assessment of ________ health and studies into vitamin D association / causality in other diseases

Answer 14

Skeletal