Growth hormone

Question 1

what is growth hormone also known as?

Answer 1

Somatotropic hormone or somatotropin.

Question 2

where is the growth hormone secreted from?

Answer 2

the anterior pituitary.

Question 3

what sort of molecule is the growth hormone?

Answer 3

Growth hormone is a small protein that contain a single chain of 191 amino acids

Question 4

how is the growth hormone released?

Answer 4

released in a pulsatile manner

Question 5

when is the measurement of growth hormone taken?

Answer 5

The measurement is either done over 24-hour period or after acute stimulation using

Insulin (hypoglycaemia)

Clonidine etc.

Question 6

what is growth hormone used for?

Answer 6

Growth hormone is essential for growth but is not the sole factor which control growth in children.

Question 7

what does growth depend on?

Answer 7

• Genetic determination
• An adequate diet
• Freedom from chronic disease and stress
• A normal level of growth-influencing hormones such as thyroid, insulin and the sex hormones

Question 8

what is the metabolic effect of growth hormone?

Answer 8

Increases fatty acid levels

Increases blood glucose level mainly by decreasing uptake of glucose

Question 9

what does the growth hormone result in?

Answer 9

the growth of soft tissues and of bones

Question 10

what is the growth of soft tissues accompanied by?

Answer 10

accompanied by both hyperplasia and hypertrophy

Question 11

what makes up bone?

Answer 11

calcium phosphate crystals in the matrix and bone cells

Question 12

what are the bone cells?

Answer 12

• osteoblasts
• osteocytes
• osteoclasts

Question 13

what are osteoblasts?

Answer 13

bone forming cells

Question 14

what are osteocytes?

Answer 14

Mature osteoblasts surrounded by organic matrix

Question 15

what are osteoclasts?

Answer 15

Multinucleated bone breaking cells responsible for reabsorption of bone

Question 16

what are the different parts of bone growth?

Answer 16

• epiphyseal growth
• growth in length
• growth in diameter

Question 17

what is included in epiphyseal growth?

Answer 17

• growth in cartilage surrounding epiphysis
• cartilage ossification
• bone remodelled

Question 18

what is included in the length growth?

Answer 18

• cartilage growth in epiphyseal plate
• cartilage ossification
• bone remodelling
• bone resorption

Question 19

what are the causes of growth hormone deficiency?

Answer 19

Pituitary hypofunction, Lack of GHRH, Abnormal GH receptors, Lack of IGF

Question 20

what are the effects of growth hormone deficiency before puberty?

Answer 20

Dwarfism : Short stature due to retarded skeletal growth with a plump body and poorly developed muscle

Question 21

what are the treatments of growth hormone deficiency?

Answer 21

Replacement therapy with growth hormone of human sequence (Somatropin) produced using recombinant DNA technology

Question 22

what are the effects of growth hormone deficiency after puberty?

Answer 22

few vague signs and symptoms

Question 23

what are the causes of excess growth hormone?

Answer 23

a tumour of pituitary

Question 24

what are the effects of excess growth hormone before puberty?

Answer 24

Gigantism : a well proportionate growth

Question 25

what are the effects of excess growth hormone after puberty?

Answer 25

Acromegaly: Thickened bones and proliferation of soft tissues results in:

• Thickening of skin
• Large spade like hands
• Large tongue
• Broadening of nose
• Projection of one or both of the jaws

Question 26

what is the treatment for excess growth hormone?

Answer 26

Surgical removal of tumour if possible
Drugs
- Somatostatin
- Bromocriptine