PHRM 4060- Thyroid
Exam Study Set
Which thyroid hormone is the most active? - Answer T3 - liothyronine
How is iodine transported into the thyroid? - Answer active transport; absorbed through
the small intestine into plasma
What 2 ions can block iodine transport? - Answer thiocyanate, perchlorate
What drug class inhibits iodine uptake? - Answer cardiac glycosides - iodide uptake
involves concurrent K+ uptake
How is radiation poisoning treated? - Answer give I-127 to outcompete I-131
What is noted about the structure of T3? - Answer missing I from the second ring (first
has both)
What is noted about the structure of reverse T3? - Answer missing I from the first ring
(second has both)
What are the functions of T3 and T4?x4 - Answer - regulate growth, metabolism,
development
- maintain homeostasis
- influence carb, protein synthesis
- cardio, renal, and brain function
What are the 2 iodinated amino acids? - Answer MIT and DIT
Tg - Answer thyroglobulin - acts as a matrix for T3 and T4 synthesis, tyrosyl rich
What is used as the matrix for T3 and T4 synthesis? - Answer thyroglobulin
How are MIT and DIT formed? - Answer I is concentrated, oxidized (IO), and
incorporated into Tg
What regulates T3 and T4 synthesis? - Answer TSH
TSH - Answer thyroid stimulating hormone; regulates release of T3 and T4
stimulates synthesis of Tg, thyroperoxidase, H2O2
Where are T3 and T4 created? - Answer on the Tg matrix
Exam Study Set
Which thyroid hormone is the most active? - Answer T3 - liothyronine
How is iodine transported into the thyroid? - Answer active transport; absorbed through
the small intestine into plasma
What 2 ions can block iodine transport? - Answer thiocyanate, perchlorate
What drug class inhibits iodine uptake? - Answer cardiac glycosides - iodide uptake
involves concurrent K+ uptake
How is radiation poisoning treated? - Answer give I-127 to outcompete I-131
What is noted about the structure of T3? - Answer missing I from the second ring (first
has both)
What is noted about the structure of reverse T3? - Answer missing I from the first ring
(second has both)
What are the functions of T3 and T4?x4 - Answer - regulate growth, metabolism,
development
- maintain homeostasis
- influence carb, protein synthesis
- cardio, renal, and brain function
What are the 2 iodinated amino acids? - Answer MIT and DIT
Tg - Answer thyroglobulin - acts as a matrix for T3 and T4 synthesis, tyrosyl rich
What is used as the matrix for T3 and T4 synthesis? - Answer thyroglobulin
How are MIT and DIT formed? - Answer I is concentrated, oxidized (IO), and
incorporated into Tg
What regulates T3 and T4 synthesis? - Answer TSH
TSH - Answer thyroid stimulating hormone; regulates release of T3 and T4
stimulates synthesis of Tg, thyroperoxidase, H2O2
Where are T3 and T4 created? - Answer on the Tg matrix
