Thyroid Hormone Flashcards
Key roles of thyroid hormone during growth and development of the fetus
Necessary for brain development
Differentiate between effect of hyper- vs hypothyroidism on carbohydrate metabolism
Hyper: increased glucogenesis and glycogenesis
Hypo: decreased glucogenesis and glucogenesis
Differentiate between hyper- and hypothyroidism on protein metabolism
Hyper: increased proteolysis and synthesis
Hypo: decreased proteolysis and synthesis
Example of a clinical sign of possible hyperthyroidism
Tachycardia - increased resting heart rate, greater than 100 bpm
Individual with chronic dietary deficiency of iodide would be at risk for what disorder
Hypothyroidism
Elevated T3 and T4, and decreased TSH are consistent with what
Hyperthyroid disorder
Most common cause of hyperthyroidism in the US
Autoimmune destruction of thyroid
Most common cause of hypothyroidism world wide
Iodide deficiency
What change in Basal Metabolic Rate is associated with decreased thyroid hormone
BMR will decrease - linear association
What is the importance of circulating T4
T4 stimulates synthesis of thyroid hormone
Describe the hypothalamus-pituitary control of the Thyroid Gland
Hypothalamus synthesizes and secreted TRH
Anterior pituitary synthesizes and secretes TSH
TSH concentration is a sensitive indicator of thyroid gland function
Why is peripheral conversion of T4 to T3 important? Which form of the hormone is biologically most potent?
T3 most potent
T4 converted to T3 or rT3 by deiodinating enzymes
In the circulation, what is the role of thyroid binding proteins?
Maintain large circulating reservoir of T4
Prevent thyroid hormone from being filtered in the kidney and excreted in the urine
