Vitamin D

Question 1

Group of sterols having a hormone like function

Answer 1

Vitamin D

Question 2

Commercial vitamin D obtained from FUNGUS, ERGOT

Answer 2

Ergocalciferol (D2)

Question 3

From exposure of skin (stratum basale) to sun, ingestion of fish, milk, plants

Answer 3

Cholecalciferol (D3)

Question 4

Most ABUNDANT circulatory form of vitamin D

Answer 4

25-hydroxycholecalciferol (25-OH-D)

Question 5

The standard method for determining patients vitamin D status

Answer 5

measurement of 25-hydroxycholecalciferol (25-OH-D)

Question 6

The biologically MOST ACTIVE form of vitamin D

Answer 6

1,25 dihydroxycholecalciferol (calcitriol)

Question 7

The rate limiting step of vitamin D synthesis

Answer 7

1 alpha hydroxylase

Question 8

Regulation of Vitamin D metabolism

Answer 8

INCREASE PTH, DECREASE Ca
DECREASE Phosphate
–> INCREASE 1,25 dihydroxycholecalciferol (calcitriol) production

Question 9

Functions of Vitamin D

Answer 9

Regulation of calcium and phosphorus homeostasis

Immunomodulatory and Antiproliferative effects

Mineralization of bones
-stimulates osteoblast to synthesize calcium binding protein osteocalcin involved in deposition of calcium during bone development

Question 10

Antiproliferative role of Vitamin D

Answer 10

Colon cancer
Breast cancer
Prostate cancer

Question 11

Beneficial effects of Vitamin D

Answer 11

Protective against cancer of prostate, colorectal cancer
Protective against cancer of prediabetes and metabolic syndrome
Prevents infection by Mycobacterium tuberculosis

Question 12

Rickets

deformity - genu varum (bowlegs)

Answer 12

BEFORE closure of epiphysis (CHILDREN)

Question 13

Osteomalacia

bone pain and muscle weakness

Answer 13

AFTER closure of epiphysis (ADULT)

Question 14

Vitamin D toxicity

Answer 14

hypercalcemia, hypercalciuria, loss of appetite, stupor

seen in GRANULOMATOUS DISEASES
increase activation of vitamin D by epithelioid macrophages