Presynaptiske
Presynaptisk refers to the part of a synapse that is on the transmitting side of the junction. A synapse is a structure that allows a neuron (nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. The presynaptic terminal, also known as the presynaptic bouton or presynaptic membrane, is where the signal originates. It contains neurotransmitters, which are chemical messengers stored in vesicles. When an action potential, an electrical impulse, arrives at the presynaptic terminal, it triggers the release of these neurotransmitters into the synaptic cleft, the space between the presynaptic and postsynaptic neurons. These neurotransmitters then diffuse across the cleft and bind to receptors on the postsynaptic membrane, initiating a response in the receiving cell. The presynaptic neuron is therefore responsible for encoding and transmitting the signal from one neuron to the next. The efficient functioning of the presynaptic terminal is crucial for communication within the nervous system and plays a vital role in processes such as learning, memory, and motor control. Disruptions in presynaptic function can lead to various neurological disorders.