The thyroid gland is located on the neck, in the region of the laryngeal cartilage and consists of two lobes connected by a bridge. In it, hormones are formed that affect metabolic processes, the development of the body, the activity of the nervous system.
In this gland, the iodine-containing hormone thyroxine is produced, which increases the intensity of metabolic processes, increases energy consumption, accelerates blood circulation and respiration.
Both excessive and insufficient thyroid function lead to the development of severe diseases.
Hypofunction of the thyroid gland
With hypofunction of the thyroid gland (insufficient production of hormones) in early childhood (3-4 years), cretinism develops in children. This disease is characterized by stunted growth, mental and physical lagging behind: dwarf growth, short limbs, swollen belly, wide-set eyes, half-open mouth.
Due to insufficient production of thyroid hormones in adulthood, a disease develops – myxedema (mucous edema). In patients, the intensity of metabolism decreases, body temperature, blood pressure, nervous system excitability decrease, heart rate slows down, hair falls out, nails break. The face becomes pale, mask-like. These patients are characterized by slowness, drowsiness, poor memory.
With hyperfunction of the thyroid gland (release of an excessive amount of hormones), Graves’ disease develops (the external signs of this disease are goiter, bulging eyes).
Overactive thyroid gland causes hyperexcitability, irritability, insomnia, and emotional imbalance. Patients with thyrotoxicosis constantly feel hunger, eat a lot, but lose weight. For the treatment of such patients, drugs are used that reduce the function of the gland, and sometimes partially or completely remove the gland.
The parathyroid glands are two pairs of small glands located on the back of the thyroid gland. They regulate the level of calcium and phosphorus in the blood, releasing parathyroid hormone, which is responsible for normal bone mineral metabolism. The formation of the hormone of the parathyroid glands depends on the presence of vitamin D in the blood:
- With an increase in the function of the parathyroid glands, calcium passes from the bones into the blood, the bones become soft, deformed and bent.
- With a decrease in the function of the parathyroid glands (or their removal), the calcium content in the blood decreases, which leads to an increase in the excitability of the nervous system and muscles – convulsions of individual muscle groups and all muscles occur.