What is the master gland of the endocrine system?
In relation to the thyroid, which hormone is secreted by the hypothalamus and acts on the pituitary gland?
Thyrotrophin releasing hormone
Which hormone is secreted by the pituitary gland and acts on the thyroid?
Thyroid stimulating hormone
Which hormones are released by the thyroid gland?
Which glands are found on the posterior aspect of the thyroid?
4 parathyroid glands
Which nerve could be damaged in thyroid surgery, almost certainly getting you sued?
Recurrent laryngeal nerve
Unilateral - swallowing issues
Bilateral - lack of phonation
Removal of the parathyroid glands during thyroid surgery may result in ___.
Thyroid pathologies have typical appearances on which imaging modality?
The thyroid takes up ___. This allows it to be seen on radionucleotide imaging.
Low uptake suggests thyroiditis, high uptake suggests Graves' disease, and unevenness in uptake suggests the presence of a nodule.
What carrier protein is found in the follicle of thyroid cells?
Thyroglobulin (which carries T3 and T4)
What is the fluid area found in the central of a follicle?
Thyroglobulin is found in which part of a thyroid follicle?
What binds to thyroglobulin to produce thyroid hormones?
How are thyroid hormones transported from the colloid to the follicular cells once they have been produced?
How are thyroid hormones transported from the follicular cells into the bloodstream?
Where are C cells found?
What do they produce?
Iodine binds to what part of thyroglobulin to form the precursors of thyroid hormones?
What is the biggest cause of hypothyroidism (i.e lack of thyroid hormone production) globally?
What antithyroid drugs are used to treat hyperthyroidism?
How do they work?
Inhibit iodination of thyroglobulin
Why do anti-thyroid drugs have a long onset of action?
Prevent NEW thyroid hormones from being made
Still residual thyroid hormone floatin around, and it's got a half life of around 10 days
Which thyroid hormone is
a) most commonly secreted
b) most potent?
T4 must be converted to __ before it can work.
Where is T4 converted to T3?
Liver and kidneys
Thyroid hormones are (hydrophilic / hydrophobic).
How are thyroid hormones similar to steroids?
Pass through cell membrane
Act on nuclear receptors to alter metabolism
Require carrier proteins to travel in blood
Thyroid hormones are released from follicular cells in response to which hormone?
On which carrier proteins are thyroid hormones transported in the blood?
Thyroxine binding globulin (TBG)
When thyroid hormones are bound to carrier proteins, they are ___.
Free thyroid hormones are (inactive / active).