What functions do hormones perform

Hormones

What are hormones

Hormones are signaling or messenger substances that are formed in specialized cells and then released into the blood. They develop their effect either on the cells in which they were formed or on cells that are more or less distant.

Where are hormones made?

The hormones are produced by specialized cells in various organs. These include, for example, the pituitary gland (pituitary gland), the thyroid gland and the parathyroid glands, the adrenal glands (marrow and cortex), the so-called islets of Langerhans in the pancreas and the gonads (ovaries, testicles).

You can find out more about these hormone-producing tissues and organs in the article "Hormonal glands".

The endocrine glands form a complex network that regulates and controls the development and function of the body in a wide variety of ways. In this network - the hormonal system - different hormonal glands can stimulate or slow each other down as needed.

You can read more about it in the article "Hormone System".

What do hormones do?

Hormones have a wide range of effects. At their destination, they trigger what are known as primary reactions, such as the formation of certain enzymes. These primary reactions in turn set secondary reactions in motion, through which the actual hormone effect unfolds in the end.

In this way, the hormone insulin, for example, lowers blood sugar levels; the adrenaline increases the blood pressure, and the male sex hormone testosterone ensures, among other things, the maturation of sperm. In all of these reactions, the hormones themselves are not used up.

In the following you will find an overview of important hormones, their place of formation and their main tasks:

Hormones Overview

What disorders can the hormones affect?

The formation and function of hormones can be disturbed in various ways - often with far-reaching consequences for the entire organism. Here are some examples:

In the case of diabetes mellitus, the blood sugar lowering hormone insulin plays a central role: In type I diabetes, the body produces too little or no insulin at all. In the case of type 2 diabetes, on the other hand, the body cells are increasingly insensitive to insulin. The result in both cases is a pathologically increased blood sugar level. If left untreated, it can seriously damage nerves, blood vessels and organs.

If there is a growth hormone deficiency (lack of somatotropin) in childhood, this leads to short stature. An excess of somatotropin in childhood results in gigantism.

In the case of an overactive thyroid, the two hormones T3 and T4 are increasingly released into the blood. Common symptoms include weight loss despite cravings, insomnia, tremors, hypersensitivity to heat, increased sweating and a racing heart.

If the thyroid is underactive, there is a lack of thyroid hormones. This leads to weight gain, fatigue, sensitivity to cold and constipation, among other things. If an underfunction of the thyroid occurs in childhood, the formation of the skeleton is disturbed - the result is a short stature; mental development is also impaired.

An increased production of cortisol can be found in Cushing's syndrome. This clinical picture is associated, among other things, with trunk obesity, a full moon face and a "bull's neck". In addition, there are often high blood pressure, high cholesterol levels and osteoporosis. Growth disorders are often seen in children.

In Addison's disease (Addison's disease), the adrenal cortex does not produce enough hormones (such as cortisol and aldosterone). The reason is either a disease of the adrenal glands, a malfunction of higher-level brain regions (such as the hypothalamus) or a long-term, high-dose cortisone intake. The lack of hormones from the adrenal cortex (cortisol, aldosterone, etc.) leads, among other things, to browning of the skin, weight loss, salt hunger, low blood pressure, indigestion, depression and irritability.

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