Neurotransmitters

Neurotransmitters are chemical carriers and serve the chemical signal transmission between nerve cells (interneuronal), as well as between nerve cells and other body cells (neuroeffective).

They are mostly low-molecular amino acids, amines or esters, which are synthesized in the nerve endings, but can also be higher-molecular peptides, which must be formed in the nerve cell nucleus. The release of neurotransmitters, mostly from the nerve endings, is induced by the flow of the ions, in particular by the calcium-influx, which occurs at the nerve end with the arrival of the excitationdepolarization.

The neurotransmitters in the switching points (Synapses) between nerves and nerves and effector cells (e.g. muscles) can penetrate the cell membranes as molecules. They are stored in small vesicles, the vesicles of the synapses and take over the chemical transmission of nerve impulses.

After release by a stimulus, the synaptic vesicles migrate at lightning speed to the presynaptic membrane, open and the neurotransmitters contained therein pour into the synaptic cleft. The neurotransmitter only takes about two to three milliseconds to transmit. It itself is rapidly inactivated either by being reabsorbed into the vesicles or by being chemically degraded with the aid of an enzyme.

Neurotransmitters are classified according to their chemical structure. Among the most important are the catecholamines, adrenalin, noradrenalin and Dopamine, Acetylcholine and Serotonin, as well as gamma-aminobutyric acid, glycine, glutamate and many other neuropeptides, which are not discussed here.

https://en.wikipedia.org/wiki/Neurotransmitter _([1])

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