The thyroid gland develops such hormones as thyroxin (Ò4) and triiodthyronine (Ò3).
In blood the most part of hormones of the thyroid gland is in the connected condition with carrier protein. They are inactive, during too time the small free fraction of hormones is active and carries out their functions.
Thyroid gland function is under the control of hypothalamo-pituitary systems. Thyreotropin-rilizing hormone is synthesized in hypothalamus (ÒRH). This hormone in pituitary stimulates formation of thyreotrophin hormone (ÒSH), which stimulates activity of a thyroid gland and formation Ò4 and Ò3.
Practically, thyroid gland’s hormones participate in all processes of organism, regulate the metabolism, synthesis of vitamins (vitamin A in the hepar), and also take part in realization of other hormones’ function in all organism. Thyroid gland diseases are accompanied both decrease and increase of its function.
Diagnostics of thyroid gland’s diseases is based on research of its functions by special laboratory methods, basic of which is ELISA.
The first stage of laboratory diagnostics of thyroid gland’s function is defi nition of thyreotrophin hormone (ÒSH) and free thyroxin (T4) level. At low ÒSH level and normal free T4 level specialists defi ne quantity of free triiodthyronine (free Ò3). It is necessary to define autoantibodies for thyroglobulin (abTG) and autoantibodies for thyroid peroxidase (abTPO) in addition to defi nition of thyroid gland’s hormones’ level for exception of autoimmune pathologies. In the diagnostic purposes specialists recommend to investigate these markers in a complex: abTG + abTPO. Other laboratory tests are carried out on orders for differential diagnostics of thyroid gland’s diseases.