Transport in blood | Thyroid hormones
Transport in blood Both thyroxine (T4) and triiodothyronine (T3) are 99% bound to the thyroxine-binding globulin (TBG) in the blood. This serves to transport the hormones and prevents an early effect of T3. Only about 0.03% T4 and 0.3% T3 are present in the blood unbound and therefore biologically active. The half-life of unbound T4 … Transport in blood | Thyroid hormones