Describe the process of thyroid hormone production:
1. Iodine is actively transported into the [blank_start]follicular thyroid cells[blank_end] via [blank_start]sodium iodide transporters[blank_end] on the basolateral side of the cell (this is called [blank_start]iodide trapping[blank_end])
2. Iodine diffuses to the luminal side of the cell
3. Iodine is transported into the follicle lumen by [blank_start]pendrin[blank_end], a membrane transporter
4. The follicle cells secrete [blank_start]thyroglobulin[blank_end] (containing ~70 [blank_start]tyrosine[blank_end] amino acids) into the lumen
5. Iodide ions undergo [blank_start]oxidation[blank_end] to form [blank_start]iodine[blank_end] via the action of the enzyme [blank_start]hydrogen peroxidase[blank_end]
6. [blank_start]Organification[blank_end] of the thyroglobulin molecule:
---Iodine binds to tyrosine amino acids within the thyroglobulin molecule via the action of [blank_start]thyroid peroxidase[blank_end]
---This forms [blank_start]monoiodotyrosine[blank_end]
---This undergoes further iodine binding to form [blank_start]diiodotyrosine[blank_end]
---MIT/DIT molecules are coupled to each other
7. If two DIT molecules couple together, [blank_start]T4 (thyroxine)[blank_end] is formed
8. If one MIT molecule couples with one DIT molecule, [blank_start]T3 (triiodothyronine)[blank_end] is formed
Respuesta
follicular thyroid cells
sodium iodide transporters
iodide trapping
pendrin
thyroglobulin
tyrosine
oxidation
iodine
hydrogen peroxidase
Organification
tyrosine peroxidase
monoiodotyrosine (MIT)
diiodotyrosine (DIT)
T4 (thyroxine)
T3 (triiodothyronine)
Pregunta 10
Pregunta
How much more concentrated is iodine in the thyroid than in the blood?