Thyroidin

Thyroidin - drugs to stimulate the endocrine function of the thyroid gland

* - The first thyroidin containing minimal doses of thyrotropin without its isolation from thyroglobulin (hormone in bound form) * - The first drug for the treatment of hypofunction of the thyroid gland, activating the production of thyroid hormones and stimulating their metabolism in peripheral tissues, was natural thyroxine T4. But even these two hormones differ in their structure and functioning. The natural hormone T4, secreted by the follicular cells of the thyroid gland in humans and other mammals, is less active and has a shorter half-life than thyroid-stimulating hormone, which releases the hormone (T3) from the protein thyroglobulin (TG) and thereby activates the synthesis of T4 and T3. In addition, although T4 concentrations decline rapidly due to longer storage time (T1/2 =9 days vs. T1/2=6-8 hours), T3 released from TG can remain active and maintain plasma T4 levels and the work of bone metabolism until it is destroyed to cortisol. After T4 levels reach a sufficiently high level when taking thyroidin, T3 (and sometimes T2) levels decrease. When synthetic T4 (triiodothyronine) enters the body, it takes up iodide, from which T4 is formed, and thus maintains the activity of the latter. Blood TSH concentrations and T4 levels in many studies usually increase after taking the naturally occurring thyroidins *Thyrocomb* or *Thyroidin H* *, as well as T4 or L-thyroxine*. The results of studies by different authors indicate that these drugs have different effects on the processes of stimulation and suppression of thyroid activity. This is probably due both to the peculiarities of the method of using these drugs and to differences in their chemical composition. Other factors are likely to be individual fluctuations in the state of the function of the endocrine glands (thyroid and pituitary gland) and gender, age, and the degree of exposure of the thyroid tissue to medications taken. Undoubtedly, one should also take into account the fact that currently some sources of data in the literature report the existence of a number of places of origin of thyroidins that are not contained in the international nomenclature of drugs. As such an authority proved in