Thyroid

Question 1

What type of hormone is TSH?

What sub-unit is unique to it?

What pathways are activated intracellular by TSH pathway?

Answer 1

Glycoprotein
B subunit
Gas (high levels Gaq also)

Question 2

What is Hasimotos disease?

Answer 2

AI destruction of the thyroid follicles.

Question 3

What are some symptoms of hypothyroidism?

Answer 3

Weight gain (obesity)
Low heart rate 
Tired
Intolerance to cold 
Slow reflexes
Myxedema (adults)(non-pitting)
Mental stuff 
GI upset (children) 
Dry skin

Question 4

What are some symptoms of hyperthyroidism?

Answer 4

Sweating
Anxiety 
Weight loss
Bulging eyes (graves)
Heart rate 
Decreased libido 
Fatigue
Heat intolerance

Question 5

What 2 symptoms are typical of Graves’ disease?

Answer 5

Pre-tibial myxedema

Exopthalmos

Question 6

What element is used in what procedures to scan the thyroid gland?

Answer 6

Technetium 99m

Scintigraphy

Question 7

What range are the concentrations of thyroid hormones in?

Answer 7

pmol/L range

10^-12

Question 8

What does TSH stimulate in the thyroid epithelial cells?

Answer 8

Iodide uptake
Iodide oxidation 
Thyroglobulin synthesis and iodisation
Colloid pinocytosis into the cell
Proteolysis of thyroglobulin
Cell metabolism and growth

Question 9

What affect does thyroid hormone have on metabolic pathways?

Answer 9

Lipid Metabolism - lipolysis and B oxidation

Carb metabolism - stimulate insulin-dependant entry of glucose into cells and increase gluconeogenesis and glycogenesis

Question 10

Give 5 enzymes activated by thyroid hormones

Answer 10

PEPCK 
Ca ATPase
Na K ATPase
Cytochrome oxidase
6-phosphogluconate dehydrogenase

Question 11

Why may TSH vary unrelated to thyroid disease?

Answer 11

Diurnal variation
Pulsatile secretion
Medication

Question 12

Usually goitre is associated with high TSH, in which situation may low TSH be associated with goitre?

Answer 12

Graves’ disease

Question 13

What may you see in infants with hypothyroidism?

Answer 13

Cretinism 
Dwarfed stature
Mental deficiency 
Poor bone development 
Slow pulse
Muscle weakness
GI disturbance

Question 14

What are some causes of hyperthyroidism?

Answer 14

Graves
Toxic multinodular goitre
SOlitary toxic adenoma 
Excessive T3 and T4 therapy 
Amiodarone 
Thyroid carcinoma
Ectopic thyroid tissue

Question 15

What is used to treat thyrotoxicosis?

Side effect?

Answer 15

Carbimazole
Pro drug - methimazole in body
Thyroid peroxidase

Neutropenia