What is Jiagong

Thyroid function is a very important part of modern medical examinations. With the decline in the quality of modern people's physical health, it is very important to use advanced medical technology to conduct regular physical examinations, and thyroid function is a very necessary examination item. Now let’s take a look at what Jia Gong is. What is the clinical significance of checking thyroid function? I hope everyone can understand this aspect.

What is Jiagong?

Thyroid function refers to the function of the thyroid gland. Generally, fasting blood tests are divided into three thyroid function tests and five thyroid function tests, the difference is the number of items checked. It is used to assess the function of the thyroid gland in secreting hormones.

The five thyroid function tests refer to five health test data of the thyroid gland, namely the measurement of thyroxine (T4), triiodothyronine (T3), thyroid stimulating hormone (TSH), free T3, and free T4.

Clinical significance:

The physiological functions of the thyroid gland are mainly to promote the metabolism of the three major nutrients, regulate growth and development, increase tissue oxygen consumption, promote energy metabolism, increase heat production and improve basal metabolism. When the thyroid gland does not function properly, hyperthyroidism or hypothyroidism can occur.

Among them, thyroxine (T4) and triiodothyronine (T3) are synthesized in the thyroid follicular epithelial cells. Under the stimulation of pituitary thyroid stimulating hormone (TSH), they undergo a series of changes and are released into the blood. More than 99% of T3 and T4 in the blood are bound to plasma proteins, mainly to thyroxine-binding globulin. Only about 0.4% of T3 and 0.04% of T4 in the total plasma are free. Only free T3 and T4 can enter the target cells to exert their effects, and the part bound to the protein regulates and stabilizes the free T3 and T4. The synthesis and secretion of thyroid hormones are mainly regulated by the hypothalamus-pituitary-thyroid axis.

Fluctuations in the levels of free T3 and T4 in the blood negatively feedback and cause an increase or decrease in the release of thyrotropin-releasing hormone TRH from the hypothalamus and thyroid-stimulating hormone TSH from the pituitary. The main function of TRH is to promote the synthesis and release of TSH by the pituitary gland. TSH stimulates the proliferation of thyroid cells and the synthesis of thyroglobulin, and promotes each process in the synthesis of thyroid hormone from iodine uptake to release.