Ensivälittäjäaineet

Ensivälittäjäaineet, also known as primary neurotransmitters, are a class of chemical messengers crucial for communication between neurons in the nervous system. They are synthesized and stored within the presynaptic neuron and are released into the synaptic cleft upon arrival of an action potential. Once in the synaptic cleft, they bind to specific receptors on the postsynaptic neuron, initiating a response that can be either excitatory, increasing the likelihood of the postsynaptic neuron firing, or inhibitory, decreasing the likelihood of firing.

The action of primary neurotransmitters is terminated by various mechanisms, including enzymatic degradation in the synaptic cleft, reuptake back into the presynaptic neuron, or diffusion away from the synapse. This rapid termination is essential for precise and controlled neural signaling. Examples of well-known primary neurotransmitters include acetylcholine, which plays a role in muscle contraction and learning, glutamate, the most abundant excitatory neurotransmitter in the brain, and gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter. Their balanced activity is fundamental for a wide range of physiological and cognitive functions.