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The thyroid hormone T3

Responsible for what the hormone T3?

The hormone T3 is the thyroid hormone, which is the most active hormone of the two major. You can meet other name – triiodothyronine. The presence of the three numbers in the definition of a hormone is because each molecule contains exactly the amount of iodine.

T3 is formed by the collapse of another hormone – T4 when one atom of iodine is cleaved from it. The process that occurs after cleavage of an atom can be compared to the process of removing the checks from grenades. Translating previously sedentary T4, transformed into triacetin becomes very active.

Its purpose is to control the energy metabolic processes in the human body. The hormone has an effect on the disintegration energy and sends it to where it is needed. Once in the bloodstream into the cells of the child's brain, the hormone contributes to its speedy development. Thanks to the work of triiodothyronine in the adult there is an increase in nerve conduction.

Triiodothyronine is important for the vascular system and bone tissue, as it contributes to the activation of metabolism in them. General nervous irritability increased under the influence of triiodothyronine.

Hormone T3 free, and General – what is it?

A certain amount of triiodothyronine is able to produce cells of the glands in the "ready"state, that is, with 3 atoms of iodine. Once in the bloodstream, is its Association with proteins-transporters. Through the vessels is the transfer of hormone to the needy in his work of tissues. But in a small amount of triiodothyronine remains in the blood, non-protein molecules. This triiodothyronine is called"hormone T3 free".

One hormone, which remains free to all, which is contacted with the protein, defined as the total hormone T3. It number is often revealing, when doubtful results of tests on hormone-free, are conducted to determine the disruption of the thyroid gland in humans.

Analysis of the hormone T3

In determining pathological conditions of the thyroid, an endocrinologist in a mandatory manner sends the patient to the test of three hormone, T4, TSH, T3. Research on this hormone is extremely important as it allows to minimize diagnostic error.

For example, for nodular toxic goiter very often independently operating nodes are playing it of the hormone T3. The number increases with diffuse toxic goiter in Graves'disease and graves disease. If the analysis produces a result that shows a significant increase in triiodothyronine, the doctors have to say about T3-toxicosis. This condition is very hard to drug correction and is more striking symptoms than those that can be detected by increasing the number of hormone T4.

Norma hormone T3

Depending on which hardware performs research on hormones, will vary the rate. Each laboratory makes a choice in favor of a particular apparatus and set of reagents. Therefore, to define the concept of "normal triiodothyronine" is impossible. The amount will be considered normal if the results meet reference the limits specified on the form specific to a specific laboratory. The form is generated on the computer where the precisely defined amount of the hormone and the limit of the rules.

Increased hormone T3

A pathological condition of the thyroid gland cause an increase in triiodothyronine. This man can not help but notice that with his body that something is happening. Due to the fact that the T3 hormone is very active, it increase in the blood causes a number of very pronounced symptoms:

  • The patient becomes excessively irritable, nervous, quickly becomes enraged and excited. Against this background, the patient constantly harass fatigue. Doctors sometimes refer to a similar complex of symptoms as the irritable weakness;
  • A tremor of fingers of the upper extremities is another frequent sign of increased triiodothyronine;
  • The patient's pulse quickens, you experience symptoms of tachycardia, is abnormal heart rhythm. Beats – a symptom of increasing hormone. This condition is characterized by increase in heart rate with long period of rest. A person feels these violations, and often makes the physician complaints about "failures" of the heart;

  • Often there is loss of body weight.

Conduct analysis to identify the level of triiodothyronine is a fairly complicated procedure. Often in the laboratories of the errors occur. Think about those independently in the case where additional test was conducted to identify the level of other thyroid hormones – TSH and T4. If the results show that TSH is normal, but the T3 hormone is elevated, it is likely that the error occurred. On the unreliability of the analysis can be judged based on an increase of T3 and TSH, but normalthe values of T4. If you have received such results, it makes sense to double-check the data. This is due to the fact that increasing T3 decreases TSH and increases T4.

If the tests were done and the results clearly indicate an increase in triiodothyronine, it is imperative to get advice from a endocrinologist.

If the hormone T3 is lowered

The decrease in the level of triiodothyronine was observed in the case when a violation of the production of all hormones produced by the thyroid gland. Found such a state in case of serious diseases:

  • There is a disease – Hashimoto's thyroiditis when the immune system of the person starts to kill some of the cells of the thyroid gland. These cells beyond repair and in most cases permanently cease to function and produce hormones.

  • Hypothyroidism. This condition often develops on the background of the intake of specific drugs used for the treatment of diffuse and nodular toxic goiter. As potentially dangerous are these thyreostatics, as Propitsil, Tyrosol, Merkazolil.

  • The level of triiodothyronine can be reduced when the operation was carried out, aimed at the removal of or the entire thyroid gland, or certain parts of it.

  • Reduced levels of T3 in the background of the passage of the human treatment with radioactive iodine. Such therapy is carried out when necessary to save the patient from diffuse toxic goiter.
  • The fall in hormone production is observed when taking drugs containing an impressive amount of iodine. Among these may be noted cordarone, amiodarone, and others.

You should know that hormones do not decrease in a chaotic manner. Always the first drop in the hormone levels of T4 and then decreases the normal value triiodothyronine. This condition is due to the activity of the body. In the fall of the T3 hormone he's trying to insure and as it translates to "cash in freely convertible currency", because triiodothyronine is more active than T4 almost 10 times. Doctors like activity of the body referred to as increased peripheral conversion of T4 to triiodothyronine. Through this process, the effects of hypothyroidism is not as sharp as could be. Knowing this, it is possible to suspect laboratory error. If the analysis showed that the level of triiodothyronine was reduced (and no matter what kind of hormone, total or free), but TSH and T4 remain in the normal range, you should double-check the data and to donate bloodon hormones again.

Because the shortage of thyroid hormones is a serious pathology. A disease in which the thyroid function is reduced, can lead to the development of processes such as: drowsiness, increase in body weight, deterioration of the thought processes and speech disruptions in the menstrual cycle in women. If the disease be severe, the child is often observed that cretinism and adults suffering from myxedema. However, peripheral conversion of hormones allows to avoid these symptoms, if treatment was initiated in a timely manner.