(Anti-) Thyroid

Question 1

concept: how do thyroid hormones increased BMR

Answer 1

increases BMR via Na/K ATPase = increases resp rate, increases temperature, increases O2 consumption

Question 2

concept: effect of thyroid hormones on catecholamines

Answer 2

increases sympa activit = increase Co and HR

Question 3

concept: effet of thyroid on brain

Answer 3

development

Question 4

Where do you find 5’iodinase (not relaly important for this i dont think)

Answer 4

peripheral tissue
liver
kidney
pituitary gland
brain
brown fat

Question 5

describe receptors fo TRH – TSH – T3/T4

Answer 5

TRH - IP3
TSH - cAMP
T3/T4 - nuclear

(Words get bigger as you go furhter down chain)

Question 6

What is levothyroxine

Answer 6

longet t1/2 T4

LEVO has four letters - thyroxine

Question 7

What is Liothyronine

Answer 7

shorter t1/2 T3

LIO has three letters - thyronine

Question 8

A/se of levothyroxine and liothyronine

Answer 8

tremors, tachycardia, arrhtymias, heat intolerace ie hyperthyroidism

Question 9

effects of rifampin, phenobarbital and phenytoin on levels of T3 and T4

Answer 9

induce P450 blleeehhh so increased metabolism so less thyroid hormone

Question 10

I say Queen Anne

Answer 10

you say laterla third eyeborw loss

Question 11

Name the Thioamides

Answer 11

Propylthiouracil

methimazole

Question 12

~*~MOA of propylthiouracil and methimazole

Answer 12

block idination of thyroglobulin and inhibit coupling reaction = reduced T3 and T4

inhibit thyroperoxidase so decreased new T3 adn new T4 but not preformed.

Question 13

Preferred drug in thyroid storm and why please

Answer 13

propylthiouracil
bc

1) inhibits 5-deiodinase – decreased conversion from T4 to T3

(methimazole does not do this)

Question 14

~*~A/se of thiamide, propylthiouracil

Answer 14

propylthiouracil = rash, agranulocytosis, aplastic anemia, hepatotoxicity, vasculitis

Question 15

~*~A/se of thiamide, metimazole

Answer 15

less severe, and therefore more preferred in clinical setting
POSSIBLE TERATOGEN

Question 16

WOLFF CHAIKOFF!!

Answer 16

iodide at high levels inhibit organification and release = lower levels, but this wanes at 10-14 days and therefore is not used for long term treatment

Question 17

Used of Iodine and Iodide salts

Answer 17

decreases vascularity and size of gland – used before surgery before excision

and tyrotoxicosis cirisis with propylthiouracil and beta blockers

Question 18

Three drugs used in thyrotoxic crissi

Answer 18

propylthiouracil
Iodine/Iodide salts
beta blockers

Question 19

Describe the prepartions available for iodine and iodide salts

Answer 19

1) lugol solution - iodine and potassium iodide

2) saturated solution of potassium iodide only

Question 20

THyroid storm again. the lecture just keeps adding drugs

Answer 20

propylthiouracil
iodine/iodide salts
beta blcokers - nadolol, atenolol

Question 21

MOA propanolol

Answer 21

non specific bb

**prevents conversion of T4 to T3

Question 22

MOA esmolol

Answer 22

short acting BB

control intraoperative thyroid storm

Question 23

DOC at intraoperative thyroid storm

Answer 23

esmolol

Question 24

DOC at thyroid storm in patients with asthma

Answer 24

diltiazem - calcium channel blocker

SHARK flashback – can complicate diabetic treatment by causeing hyperglycemia in diabetics

Question 25

What do you give to prevent peripheral conversion of T4 to T3 in thyroid storm

Answer 25

holy monkeys thyroid storm ``` propylthiouracil IV sodium iodine glucocorticoids bb diatrizoate and iohexol ```

Question 26

MOA of diatrizoate and iohexol

Answer 26

iodinated radiocontrast medial that suupresses action fo 5'iodinase - no conversion of T4 to T3 use at tyrotoxicosis to decreased T3 concentraiton

Question 27

Perchlorate Thiocyanate Pertechenetate MOA

Answer 27

inhibit iodide concentation in gland by blockign transportation

Question 28

Why do we care about amiodarone *coat of many colours*

Answer 28

structural similarity with thyroxine a) iodine associated hyperthyroidism b) autoimmune mediated inflammatory version <-- treat with steroids c) hypothyroidism due to blockade of T4 to T3

Question 29

How to treat iodine associated hyperthyroidism caused by amiodarne

Answer 29

thiamides - propylthiouracil and metimazole

Question 30

Lithium affect on thyroid style

Answer 30

inhibits release of hormones (hypothyroidism) and causes thyroid enlargement

Question 31

Name some drugs that provoke autoimmune or destructive inflammatory thyroiditis to induce hypothyroidism

Answer 31

a) amiodarone b) IFNalpa c) IL-2 d) Litihium

Question 32

What do these drugs have in common a) amiodarone b) IFNa c) IL-2 d) Lithium

Answer 32

all provoke autoimmune or destructive inflammatory thyroidiits resulting in hypothyroidism

Question 33

SHARK: Name three drugs that inhibit conversion of T4 to T3

Answer 33

corticosteroids propranolol amiodarone

Question 34

Name some goitrogens

Answer 34

cabbage - thiocyantae (prevents uptake of I) | cassava - carbs _ thioc;yanate (prevents uptake of I with perchlorate and pertechetol)