Synonyms in a broader sense
- Beta-receptor blockers
- Beta-adrenoceptor blocker
- Β blocker
Definition
Beta-blockers are mainly used in the therapy of cardiovascular diseases, but there are also other areas of application. This group of drugs blocks the docking of messenger substances to the so-called beta receptors, which are found on the heart, lungs, muscles, pancreas, kidneys, blood vessel walls and fatty tissue. They thus prevent the messenger substances from having their effect.
Messenger substances that attack the beta receptors and cause an effect are the hormones adrenaline and noradrenaline, which are called catecholamnia and originate from the stress-mediating (sympathetic) nervous system. The processes that occur as a result of activation of the beta receptors are, for example, an increase in the heartbeat, a rapid pulse, narrowing of the vessels, dilation of the lungs when inhaled or the provision of sugar from the energy stores of the muscles. With the help of beta-blockers these processes can be influenced, which can be used for therapeutic purposes.
General effect
Beta-blockers block specific receptors located on a variety of different cells and organs throughout the body. They are usually taken in tablet form and enter the bloodstream via the gastrointestinal tract. They are distributed throughout the body via the blood and unfold their effect at the so-called beta receptors.
Receptors are docking points on the cells for messenger substances. According to the lock-and-key principle, only certain substances can bind to the special receptors. By blocking the beta receptors, beta blockers generally inhibit the action of the stress hormones adrenaline and noradrenaline, which normally mediate their action via these receptors.
As a result, the heart rate and blood pressure, for example, drop. In the lungs, the drugs lead to a narrowing of the bronchial tubes. As there are different types of beta receptors in the body (especially beta-1 and beta-2), we distinguish between the selenium beta blockers, which only act on one of the subtypes, and the non-selective ones, which can bind to beta-1 and beta-2.
Beta-blockers act on the heart in different places at the same time. First of all, the heart rate and thus the pulse is lowered, which is particularly useful in case of heart rhythm disturbances with a too fast heartbeat. Furthermore the beta blockers reduce the force with which the heart beats.
This also reduces the energy and oxygen consumption of the heart muscle. This is particularly important in coronary heart disease and heart attacks. These effects on the heart also lower blood pressure, so beta-blockers can be used to treat high blood pressure. However, beta-blockers can also have a positive effect in cases of weakness of the heart pump (heart failure), as they make heart work more economical.
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