Dispersion in Excitatory Synaptic Response

Due to its extreme importance for brain activity, the function of the excitatory synapse is the object of a huge amount of researches investigating the specific contribution to the synaptic response of fairly all its structural elements. Here, we utilized amodel of hippocampal synapse to describe the random dispersion of the response evaluated from the dispersion of the amplitude peak of the miniature Excitatory Post-Synaptic Current (mEPSC). The model is based on time discretized Langevin Equations which describe the Brownian motion of Glutamate molecules released by a neurotransmitter vesicle within the synaptic cleft, their collisions with the structural elements, their binding to post-synaptic receptors and their final spillover. The value of the amplitude peak of the computed mEPSCs was put in relationship with different binding probabilities and different number of AMPA receptors. The dispersion has been used to compute an appropriate value of the binding probability of Glutamate molecules to post-synaptic receptors.