Hormones – function, structure & symptoms

Hormone

Hormones are endogenous substances that are mostly produced in endocrine glands. These are immediately released into the blood. They are thus transported throughout the entire organism. They are effective even in small doses and control, regulate and coordinate vital processes in cells and organs.

What are hormones?

The activity of our organs is controlled on the one hand by the nervous system and on the other hand by the hormone system. Hormones are formed in the appropriate glands, the endocrine glands, and then released into the bloodstream. With the help of the circulatory system, they reach every organ or cell in our body.

Hormones are effect-specific, ie they are only responsible for very specific processes in the cells. Because of this, they are also referred to as active ingredients. Their effect is usually based on accelerating or slowing down metabolic processes.

Hormones can inhibit or promote the way they work, which ultimately results in precise control and regulation of all important processes in the body’s cells. Even a small dose is enough to develop its full effectiveness.

The relatively rapid breakdown of the hormones prevents them from accumulating in the blood and their effects are thus overridden in a controlled manner. The body is only able to reduce the hormone concentration by breaking it down.

However, changing the amount of hormones is often the prerequisite for controlling a specific organ function at all. The hormone system uses certain secretions to transmit information. It works slowly but with a lasting effect.

Mode of action

Hormones are not species-specific in their effect, ie hormone preparations for humans can also be obtained from animal glands. The control and coordination of the many different tasks of the human body takes place through the cooperation of the endocrine system with the nervous system.

Both organ systems conduct information to organs and trigger specific reactions. In this respect, the nervous system works with electro-chemical impulses, which are transmitted on the fastest conducting nerve pathways and enable an immediate reaction. It is responsible for responding quickly and directly to environmental stimuli. The organs are also directly supplied with information via nerves.

The hormone system, on the other hand, works much more slowly, since the formation, the release of the hormones from the glands and the subsequent path through the bloodstream are more time-consuming. It is designed to function for a longer period of time, with continuous performance (e.g. when escaping) being ensured by the persistently acting hormones. After stressful situations, the excitement persists until the last hormones have been eliminated. For this reason, we cannot calm down for a long time after excitement because the stress hormones are still active in our body.

The group

There are two large groups of hormones depending on where they are formed. These are the glandular hormones and the tissue hormones.

Drüsenhormone

Glandular hormones are formed in endocrine or endocrine glands because they release their products immediately into the blood flowing through them. In humans, these are the pituitary gland (pituitary gland), the epiphysis (pineal gland), the thyroid gland, the parathyroid glands (epithelial bodies), the islets of Langerhans of the pancreas, the adrenal glands and the gonads (ovaries, testicles).

tissue hormones

Tissue hormones are formed in tissues, but their main task is quite different. Some tissue hormones are released to the immediate vicinity of where they are formed and have their full effect there. The tissue hormones include, for example, gastrin in the gastric mucosa. Its job is to stimulate hydrochloric acid production when you eat.

Another hormone is secretin of the small intestine. It stimulates the production of pancreas and reduces the formation of hydrochloric acid in the stomach.

Renin, a hormone produced by the adrenal glands, increases blood pressure. Neurohormones, formations of certain nerve cells, react to the thymus gland and thus influence the immune system . (Thymus gland – in it the maturation process of the precursors of the lymphocytes, which are formed in the bone marrow, to fully functional T-lymphocytes takes place.) This clearly expresses that there is a very close relationship between the hormone system, the nervous system and the immune system.

Glands

The primary task of the gonads is to form sex cells in order to ensure the survival of the species. If these glands are removed from the body of a living being by castration at an early stage, the development of secondary sexual characteristics is prevented. A being emerges that stands between the sexes. That not only has different physical characteristics, but also character and temperament are subject to change. There are numerous examples: An aggressive stallion becomes a tame gelding through castration, a wild bull becomes a good-natured ox, a castrated rooster (capon) also loses its aggressiveness but also loses its comb and wattles. However, it retains its colorful plumage.

Hormones of the gonads, the sex hormones, influence sexual and physical development, the entire metabolic process and the human psyche. During puberty, there is an increased production of gonad hormones, which triggers the maturation of the sexual organs and secondary sexual characteristics (eg genital hair). In every body there are also sex hormones of the opposite sex. The quantitative ratio of the different hormones is decisive for the development of characteristics as a boy or girl. Disturbances in this regard can lead to the formation of “pseudohermaphrodites”. whose secondary sex characteristics do not correspond to the genetically determined sex.

The male gonads, the testicles, produce the most important male gonad hormone, such as testosterone. This hormone is responsible for the maturation of the testicular tissue and for the continuous formation of sperm in it. It controls the development of secondary sexual characteristics in men and, in higher concentrations, stops body growth during puberty.

The hormones of the ovary cause the development of the female sexual characteristics, the development of her reproductive organs and the maturation of the egg cells in the ovary. They also regulate the menstrual cycle and, after fertilization, ensure that the zygote (fertilized egg cell) is embedded in the mucous membrane of the uterus. They also regulate the entire course of pregnancy and milk production.

Adrenal glands

The adrenal glands sit on the kidneys like small valves and consist of the renal cortex and the renal medulla. However, they have nothing to do with the function of the kidneys. Rather, their two types of tissue (marrow and cortex) produce different hormones. The hormones adrenaline and noradrenaline are produced in the kidney medulla. These hormones influence the state of physical activity and regulate, among other things, blood sugar levels.

The hormones of the adrenal cortex are cortisol and aldosterone, they are called corticoids. This group of hormones affects the mineral balance and is responsible for a balanced ratio of sodium and potassium ions in the blood and tissues. They also influence carbohydrate and protein breakdown. Cortisol promotes glucose synthesis in the liver and provides an anti-inflammatory and healing effect on the immune system.

In a stressful situation that occurs suddenly, increased amounts of adrenaline and noradrenaline are released into the blood after corresponding impulses by the vegetative nervous system. The entire body is adjusted to maximum performance, to an enormous willingness to perform. He is put on alert so that he can react quickly. Such reactions are characterized by an increased heartbeat, increased blood flow to the muscles and all activated organs.

Furthermore, a breakdown of fat to free fatty acids takes place, the pupils are dilated, there is also an increase in the blood sugar level and increased sweating . On the other hand, all organs involved in digestion are inhibited.

Function

Each endocrine gland produces specific secretions for the coordination and regulation of concrete life processes. Serious functional disorders and symptoms occur when hormones are over- or under-produced. Disturbances of a single endocrine gland can lead to far-reaching functional impairments of other important glands. All glands influence each other and are therefore dependent on each other.

The pituitary gland, the pituitary gland, which is about the size of a pea, is of particular importance. It is located at the bottom of the brain and is connected to the diencephalon. The activity of the pituitary gland is stimulated by nerve impulses. It is responsible for the formation of several hormones.

As the superordinate organ, the pituitary gland controls the function and interaction of all other endocrine glands. In this regard, she is able to influence her hormone production and release and prevent overproduction. Thus, the pituitary controls growth (through the production of growth hormone) and all metabolism and energy metabolism in the body.

Hormonal imbalances

In today’s world, stressful situations often arise, which put our body on alert again and again. These can include family conflicts, professional demands or road hazards that have a negative impact on us over a longer period of time. Normally, our body reacts to stress with appropriate body movements such as flight or attack. As a result, the hormones formed are broken down relatively quickly and the subsequent stressful body reactions are quickly stopped.

However, if alarming external stimuli have a constant effect on us and are not switched off, important organs can malfunction. Over time, corresponding damage to the circulatory system, kidneys and digestive organs occurs, which leads to disorders or diseases of other organs.

Long-term stress can also be environmental stimuli such as lack of oxygen, pain, cold, intense heat, suffering, sadness and infections, the overall condition of which is referred to as stress.

Our body can react specifically to individual stress factors, the stressors. For example, he can generate heat in response to hypothermia through rhythmic muscle contractions (shivering) to protect himself from frostbite.

The body always reacts with a constant reaction pattern, the general adaptation syndrome (AAS). In such cases, the adrenal glands become enlarged and associated with the increased release of corticoids into the blood.

Subsequent reactions are the build-up of glucose from protein building blocks , high blood pressure and changes in the composition of the blood with regard to the ion concentration and its serum protein. As a result, the AAS provides effective protection against harmful environmental influences if the exposure time to stressors is short.

Long-lasting or frequent stressful situations in quick succession lead to an overload of the organs. Your damage is therefore already pre-programmed. Excessive stress (distress) always has a damaging effect on the body. Stress in moderation (eustress) can contribute to the activation of the organism and keep it in an extremely positive active state.

Dorothy Farrar

Hello and welcome to my Health Guide & Encyclopedia! My name is Dorothy Farrar, and I'm the founder and main author of this platform.
My passion for health and wellness started at a young age when I became interested in the connection between the food we eat and the way we feel. This fascination led me to study nutrition and dietetics in college, where I learned about the importance of a balanced diet and the impact of various nutrients on the body.

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