A thyroid hormone. It affects almost every physiological process in the body, including growth and development, metabolism, body temperature, and heart rate
An endogenous prohormone released from the follicular cells of the thyroid gland.
TSH (Thyroid Stimulating Hormone)
Test is used to check for thyroid gland problems. TSH is produced when the hypothalamus releases a substance called thyrotropin-releasing hormone (TRH). TRH then triggers the pituitary gland to release TSH.
TSH causes the thyroid gland to make two hormones: triiodothyronine (T3) and thyroxine (T4). T3 and T4 help control your body's metabolism.
Triiodothyronine (T3) and thyroxine (T4) are needed for normal growth of the brain, especially during the first 3 years of life. A baby whose thyroid gland does not make enough thyroid hormone (congenital hypothyroidism) may, in severe cases, be mentally retarded. Older children also need thyroid hormones to grow and develop normally.
This test may be done at the same time as tests to measure T3 and T4.
An arbitrary value obtained by multiplying the triiodothyronine uptake by the serum thyroxine concentration; it largely corrects for variations in thyroid-bound globulin concentration by providing a clinically valid estimate of the physiologically active free thyroxine; direct assay or laboratory measurement of free serum thyroxine yields a more accurate value.
Is used by doctors to estimate the amount of TBG in the blood, and how much T4 and T3 in the blood is free form and available to affect the body.
Thyroid Peroxidase Antibody
Thyroid peroxidase (TPO), an enzyme normally found in the thyroid gland, plays an important role in the production of thyroid hormones. A TPO test detects antibodies against TPO in the blood.
Thyroid Receptor Antibody
A test that measures the amount of an antibody (thyroid-stimulating antibody) which is directed against a receptor for TSH on the thyroid gland. This antibody acts like TSH and stimulates the thyroid to produce excessive amounts of thyroid hormone. The presence of this antibody generally indicates Grave's disease (hyperthyroidism).