THYROID HORMONE-BINDING PROTEINS

Question 1

• It transport majority of T3
• Transport 70% of total T4
• Bind with T3
• The affinity of T3 to TBG is lower compared to T4

Answer 1

Thyroxine Binding Globulin (TBG)

Question 2

Reference Range of TBG

Answer 2

10 - 26 ug/dL

Question 3

Also known as Transthyretin

Answer 3

Thyroxine-Binding Prealbumin

Question 4

• It transport 20% of Total T4
• T3 has no affinity for Prealbumin

Answer 4

Thyroxine-Binding Prealbumin

Question 5

• It transport T3 and 10% of T4

Answer 5

Albumin

Question 6

• These are MORE SPECIFIC INDICATOR OR THYROID FUNCTION
• The values are NOT AFFECTED by TBG
• They crosses the cell membrane unlike the protein bound

Answer 6

FREE T3 and T4

Question 7

• It is RESPONSIBLE FOR THE METABOLIC ACTIVITY of thyroid hormones
• They are the BEST INDICATOR of thyroid status

Answer 7

Free T3 and T4