Multiscale modeling of presynaptic dynamics from molecular to mesoscale
Fig 5
Multi-Exponential Shape of Ca2+-Driven Vesicle Release Rate.
(A,B) Plots given as semi-log to highlight exponential decay components (straight line segments of profiles). (A) A single, spike-evoked [Ca2+]i transient, which drives (B) the synchronous and asynchronous release rates. (C) Instantaneous time constants for Ca2+, synchronous, and asynchronous curves, calculated from the well-mixed model (see Eq (2)). Long release rate time constants (around 80 ms and 1000 ms; dashed lines) follow Ca2+ curve due to slow un-buffering of latent Ca2+. Asynchronous starts high because fast and slow components have comparable magnitude and become conflated; it goes up to infinity where additive effects cause the curve to flatten.