Electrical events called "action potentials" cause the neuron to release a chemical neurotransmitter into a small space, called the
synaptic cleft, between it and a neighboring (postsynaptic) neuron.
To further address the question regarding a decrease in the Purkinje cell number, as seen in the diabetes, and whether it was attributable to diminished synapse density, we performed ultrastructural studies of the synapses, using transmission electron microscopy to provide the information regarding the presynaptic area that contained the neurotransmitter vesicles,
synaptic cleft, and postsynaptic area, as shown in the Figure 3A.
He explains that in this exercise, the musical whole notes represent all the neurochemicals traveling the
synaptic cleft; the half notes are the neurotransmitters and quarter notes are specific neurotransmitters, such as glutamate.
A, B, C - Control preparations incubated with Tyrode solution (vehicle); A, shows the typical terminal bouton with synaptic vesicles (SV) polarized in front of the
synaptic cleft and with mitochondria (M) positioned at the opposite site; B, shows detail of the post-synaptic junctional folds exhibiting the classical electron density of the sarcolemma where acetylcholine receptors (AChRs) are abutted (arrows); C, confirms the integrity of the AChRs labeled with TRITC-conjugated [alpha]-BTX.
In parallel, inflammation affects physiological mechanisms of glutamate clearance at
synaptic cleft. This together with enhanced glutamate release from glial cells over activates AMPARs, thus contributing to induce excitotoxic mechanisms and synaptic loss.
Its effects on serotonin and norepinephrine at the
synaptic cleft and neuromuscular junction could provide relief for those who have not found relief from other therapies.
Propofol can also recruit new subunits such as a4 to the surface of a neuron via increasing a4 subunit mRNA.[sup][20] (2) Neonatal propofol exposure might increase GABAergic
synaptic cleft distance.