Synapse structure and function
This image represents a chemical synapse taking place between two neurons, in green the pre-synapse and in red the post-synapse, showing how these structures look like when imaged by transmission electron microscopy (in grey). In the pre-synapse you can see a mitochondrion (necessary for the formation of the ATP, the source of energy of the cell), synaptic vesicles in the close proximity of the active zone (in the so-called ready releasable pool), and vesicles that already fused with the membrane of the active zone and that are releasing their messenger content in the synaptic cleft. You can also notice some neurofilaments (dark lines), dark big vesicles usually containing neuropeptides, and vesicles in the reserve pool in the upper part of the synapse. The post-synapse is characterized by the presence of a dark area, called post-synaptic density (PSD), formed by many proteins such as neurotransmitter receptors, structural proteins, and signalling proteins.
Genetic mutations of synaptic proteins are cause of diseases such as epilepsy, autism spectrum disorders, schizophrenia.
Psychoactive drugs act through many ways of action, such as blocking the post-synaptic receptor or inhibiting the pre-synaptic re-uptake of the neurotransmitter from the synaptic cleft.
This image has been published on http://revistageneticamedica.com/2015/07/21/un-duo-molecular-regula-genes-neurales/.
