Axonterminált

Axonterminált, also known as the synaptic terminal or terminal bouton, is the specialized ending of an axon. It is the site where a neuron communicates with another cell, typically another neuron, muscle cell, or gland cell. This communication occurs through a process called synaptic transmission. The axonterminált is a small, bulbous structure that contains a variety of components crucial for neurotransmission.

Within the axonterminált, synaptic vesicles are present. These small sacs are filled with neurotransmitters, which are chemical messengers. When an electrical signal, the action potential, arrives at the axonterminált, it triggers the influx of calcium ions. This influx of calcium ions causes the synaptic vesicles to fuse with the presynaptic membrane, releasing their neurotransmitter contents into the synaptic cleft. The synaptic cleft is the narrow space between the axonterminált and the postsynaptic cell.

The released neurotransmitters then diffuse across the synaptic cleft and bind to specific receptors on the postsynaptic membrane of the target cell. This binding initiates a response in the target cell, which can be either excitatory or inhibitory, depending on the type of neurotransmitter and receptor involved. After releasing their neurotransmitters, the synaptic vesicles are recycled or resynthesized, and the process is ready to repeat. The structure and function of the axonterminált are fundamental to the nervous system's ability to process and transmit information.