Figure 5. Model of synaptic input-mediated modulation of mitochondrial motility.

(A) Distribution of mitochondrial arrest durations generated by the model for mean durations of 1–5 min. (B) Changes of mitochondrial motility after onset of simulated synaptic inputs for a mean arrest duration of 1 min. Input frequencies are given as total synaptic inputs along a 100 µm stretch of dendrite. Low input frequencies hardly changed overall mitochondrial motility. Higher input frequencies reduced motility substantially. Steady state was reached after a few minutes. Colored lines: individual simulations, black lines: average of 10 simulations. (C) Relationship between synaptic input frequency and mitochondrial motility for different arrest durations at steady state. The expected increase of synaptic activity from postnatal day (P) 5 to P12 reduced mitochondrial motility by 30–60%, depending on the actual duration of mitochondrial arrest after synaptic transmission.