A comparison of deterministic and stochastic simulations of neuronal vesicle release models.
We study the calcium-induced vesicle release into the synaptic cleft using a deterministic algorithm and MCell, a Monte Carlo algorithm that tracks individual molecules. We compare the average vesicle release probability obtained using both algorithms and investigate the effect of the three main sources of noise: diffusion, sensor kinetics and fluctuations from the voltage-dependent calcium channels (VDCCs). We find that the stochastic opening kinetics of the VDCCs are the main contributors to differences in the release probability. Our results show that the deterministic calculations lead to reliable results, with an error of less than 20%, when the sensor is located at least 50 nm from the VDCCs, corresponding to microdomain signaling. For smaller distances, i.e. nanodomain signaling, the error becomes larger and a stochastic algorithm is necessary.
Modchang
Charin
C
Center for Theoretical Biological Physics, University of California, San Diego, La Jolla, CA 92093, USA.
Nadkarni
Suhita
S
Bartol
Thomas M
TM
Triampo
Wannapong
W
Sejnowski
Terrence J
TJ
Levine
Herbert
H
Rappel
Wouter-Jan
WJ
D000465:Algorithms; D002118:Calcium / Q000378:metabolism*; D003198:Computer Simulation; D008959:Models, Neurological; D009010:Monte Carlo Method; D009474:Neurons / Q000378:metabolism*; D013269:Stochastic Processes; D013569:Synapses / Q000378:metabolism*
D002118:Calcium