Exam 3: Thyroid Hormone Flashcards
How much iodine is required each year?
50mg
Iodine transport utilizes what type of transporter?
Sodium-Iodide symporter (2:1)
Where does the energy for the sodium-iodide pump come from?
Na/K ATPase pump
Iodide is transported across the apical membrane via a _____-_____ _____-transporter called _____.
Chloride-Iodide
Counter
Pendrin
Thyroxin is stored in the _____ of the thyroid gland.
Follicles
Thyroglobulin use what to bind iodine and form thyroid hormones?
Tyrosine
Most of the iodinated tryrosine in the thyroglobulin is recycled and becomes _____ _____.
Deiodinase enzyme
Grave’s disease and Adenoma are 2 major causes of what disease?
Hyperthyroidism
What are common treatments for hyperthyroidism?
Surgical removal & treatment with radioactive iodine
What must one be careful of when removing the thyroid?
Not to remove the parathyroid as well.
Hashimoto disease, Endemic goiter, & Cretinism are major causes of what disease?
Hypothyroidism
What is a common treatment for hypothyroidism?
Oral medication
How do thiocyanate ions act as antithryoid drugs?
Inhibit iodine uptake
How does propylthiouracil act as an antithyroid drug?
Inhibits peroxidase
How do iodides act as antithyroid drugs?
Decrease thyroid activity when present in high concentrations
How does thyroid hormone affect gene transcription?
Causes large increase resulting in an increase in functional activity throughout the body
T/F: Thyroid hormone causes both anabolism and catabolism of protein, as well as all other cellular metabolic functions, to increase.
True
T/F: Thyroid hormone acts negatively on the fetal brain.
False, promotes growth and development
What affect does thyroid hormone have on carbohydrate metabolism?
Increases all forms of carb metabolism including insulin secretion
T/F: Thyroid hormone decreases rate of GI secretion of digestive juices.
False, increases
Anxiety, extreme worry, and paranoia are symptoms of hyper/hypo-thyroidism?
Hyperthyroidism
A slight increase in thyroid hormone causes muscles to react with _____, while excessive thryoid hormone causes the muscles to _____.
Vigor
Weaken
What is one of the most characteristic signs of hyperthyroidism?
Fine muscle tremor
T/F: Hyperthyroidism causes one to feel energized.
False, tired
T/F: Hyperthyroidism causes loss of libido in both men and women.
False, hypothyroidism
What thyroid hormone causes increased activity of all known secretory functions of the thyroid glandular cells?
TSH
How does cAMP increase activity of the thyroid glandular cells?
By activation via TSH
What is released by the median eminence of the hypothalamus and acts to secrete TSH?
TRH
Cold causes increased _____ secretion via the _____, & therefore, _____ secretion via the _____ _____.
TRH, hypothalamus
TSH, anterior pituitary
