title: A comparison of deterministic and stochastic simulations of neuronal vesicle release models.
abstract: 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.
authors.affiliation: Center for Theoretical Biological Physics, University of California, San Diego, La Jolla, CA 92093, USA.
authors.forename: Charin
authors.initials: C
authors.lastname: Modchang
authors.forename: Suhita
authors.initials: S
authors.lastname: Nadkarni
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Bartol
authors.forename: Wannapong
authors.initials: W
authors.lastname: Triampo
authors.forename: Terrence J
authors.initials: TJ
authors.lastname: Sejnowski
authors.forename: Herbert
authors.initials: H
authors.lastname: Levine
authors.forename: Wouter-Jan
authors.initials: WJ
authors.lastname: Rappel
mesh_terms: 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*
chemical_list: D002118:Calcium