6: Neurotransmission

As mentioned above (Figure 3), information is transmitted in the brain through a process called neurotransmission. Neurotransmitters contain various chemical substances called "neurotransmitters". One such neurotransmitter is known as "dopamine". During normal communication, dopamine is released into the synapse by neurons (small gaps between neurons). Later dopamine binds to specific proteins on adjacent neurons called "dopamine receptors" (see figure) and signals the neurons.

Chemical neurotransmission occurs at a chemical synapse. In chemical neurotransmission, presynaptic neurons and postsynaptic neurons are separated by small gap-synaptic gaps. The synaptic cleft is filled with extracellular fluid (all cells immersed in the brain). Although very small, usually on the order of a few nanometers (one billionth of a meter), the synaptic gap creates physical barriers to transfer the electrical signal carried by one neuron to another neuron. Electrically, the synapse clearance is considered a "short circuit" in the circuit. The function of the neurotransmitter is to overcome this electrical short circuit. It acts like a chemical messenger that ties the action potential of one neuron to the synaptic potential of another neuron. How this happens is explained in the animation below.

During neurotransmission, presynaptic neurons release neurotransmitters into the synaptic cleft, which bind to homologous receptors expressed in postsynaptic neurons. Based on the interaction between the emitter and the receptor, the neurotransmitter can induce various effects such as stimulation, inhibition or induction of the second messenger cascade in postsynaptic cells. Based on cells, these effects may result in in situ synthesis of endogenous cannabinoid anandamide or 2-AG, the process is not completely clear, but is caused by an increase in intracellular calcium . Since expression appears to be exclusive, both types of endogenous cannabinoids are not co-synthesized