Definition
Histamine belongs to the so-called biogenic amines and fulfils a number of different tasks in the human body. Histamine is contained in food in more or less high concentrations and can therefore be absorbed by the body through food. If the breakdown of histamine is disturbed, a so-called histamine intolerance can occur. There are four known different receptors in the body to which histamine can bind and fulfil different functions.
Function and effect of histamine in the body
Histamine takes over a variety of essential tasks in the body. It is assumed that not all functions of histamine have yet been researched and that studies will reveal a number of other functions of the messenger substance in the coming years. Above all, histamine serves as a messenger substance in inflammatory and allergic processes.
During an inflammation, the release of histamine causes blood vessels to dilate and tissue to swell. Histamine also causes the release of other substances that are needed during an inflammation. It thus supports the body in fighting invading pathogens.
Blood vessels are dilated so that more blood can enter the inflamed area and the body’s immune cells can fight the intruder. This can be recognized externally by a reddening of the skin or mucous membrane. Histamine is also responsible for itching and a runny or stuffy nose in allergies.
The swelling of the mucous membranes and thus congestion of the nose, should lead to the entry port being closed. The affected person notices this by poorer breathing. Strong allergic reactions also lead to a deterioration of the general condition, tiredness, exhaustion, headaches and indisposition.
Sometimes fever can also be associated with these allergic symptoms. Since the histamine effect occurs very quickly in an allergic reaction, it is also called an immediate reaction. Histamine also plays an important role in the central nervous system.
As a neurotransmitter, it serves to transmit important information. Especially the nausea stimulus and the sleep rhythm are significantly influenced by histamine. By inhibiting certain receptors, histamine can also influence the release of other messenger substances in the brain.
Current studies are investigating other possible tasks that histamine may perform in the brain. The presence of histamine is also an important factor in digestion. For example, histamine is largely responsible for the production of gastric acid and stimulates digestion by increasing intestinal movement. In the cardiovascular system, histamine causes dilation of small vessels, while large vessels become narrow due to the influence of histamine, which affects blood pressure. Histamine increases the strength of the heart and the frequency of the heartbeat.