Computer models for ions under electric and magnetic fields: random walks and relocation of calcium in dendrites depends on timing and population type

In this computational study we analyze segregated population of ions in biological tissues and how electric or magnetic fields can relocate them. The appropriate definition of a segregated population of ions is justified for its physiological relevance, algorithmic simplicity and biophysical realism. Although this study can be valid for several ions and cell compartments, we focus on calcium ions in parallel dendrites of neurons. Computer simulations are presented as calcium flux visualizations showing the final position of each ion in different conditions in neurons: in the absence of an electric field and in the presence of it at different timings in relation to the initial release event of calcium into the dendrites. The simulation suggests that it is possible to relocate (probabilistically) aggregations of calcium ions in the spaces of the dendrites, allowing neuromodulation of synaptic connections. In conclusion, the maximal response to endogenous electric fields and the efficient way to design “friendly” devices for electrical field stimulation of neurons for relocating calcium ions close to their targets (e.g. vesicle sensors, proteins in membranes, or cytosol) depends on the geometry of dendrites, the duration and timing of the field (respect to ongoing activity), and the selection of the appropriate subpopulation we want to relocate.
https://link.springer.com/chapter/10.1007/978-981-10-4086-3_175