Thyroid and Pineal Glands

Question 1

what are the key hormones in normal thyroid physiology?

Answer 1

TSH, T4 and T3

Question 2

__ is more abundant in circulation while __ is the most active/what your organs care about

Answer 2

T4, T3

Question 3

what happens when theres a lack of iodine in the diet?

Answer 3

excessive growth of the thyroid gland = too much thyroglobulin backing up stimulating the hormones to overwork

Question 4

identify the functions of thyroid hormone in the body

Answer 4

relates to metabolism:
regulates use of calories
impacts heart rate
thermoregulation
influences digestion
maintains skin, muscle and bone
impacts brain developing in neonates

Question 5

how might hyperthyroidism present in a cat or adult horse?

Answer 5

weight loss
polyphagia
polyuria/polydipsia
vomit or hyperactivity
unkept coat
HCM

Question 6

how might hypothyroidism present in dogs and foals?

Answer 6

fatigue
weight gain
muscle weakness
dry skin
thin coat
bradycardia
hypothermia

Question 7

cat with hyperthyroidism

Answer 7

low TSH
High T3 and T4

likely producing thyroid hormone without being told (tumor likely)

Question 8

dog with hypothyroidism

Answer 8

high TSH
low T3 and T4

Question 9

euthyroid sick syndrome

Answer 9

TSH is normal/low
T4 is normal/low
T3 is low

patients are sick unrelated to thyroid but it effects function and metabolism. Meds can also cause this

Question 10

autoantibodies effects on formation of T3 and T4

Answer 10

autoimmune destruction of thyroglobulin prevents the formation of T3 and T4 resulting in elevated TSH, Low T3 and T4 with high TgAA

Question 11

summarize the feedback loops to they thyroid

Answer 11

hypothalamus -> TRH -> Anterior Pituitary -> TSH -> Thyroid -> T3 and T4

negative feedback to the anterior pituitary and hypothalamus