Table 2. Model parameters.

Parameters		Values	References/notes
Bouton volume		0.13 * 10–15 l	Schikorski and Stevens, 1999 *
Calcium	[Ca2+]rest	30*10–9 M	Measured
	D	220 *10–12 m2s–1	Allbritton et al., 1992
Fluo-5F	[Fluo]	140 *10–6 M	70% of pipette concentration
	K D	439 *10–9 M	Measured
	k off	300 s–1	Scott and Rusakov, 2006
	D	220 *10–12 m2s–1	2†
EGTA	K D	7*10–8 M	Klicken Sie hier, um Text einzugeben (Nägerl et al., 2000)
	k off	0.7 s–1	ibid.
	k on	1*107 M–1s–1	ibid.
	D	220 *10–12 m2s–1	Naraghi and Neher, 1997
ATP	[ATP]	6 *10–4 M	Pipette concentration
	K D	2*10–4 M	Meinrenken et al., 2002
	k off	100 000 s–1	ibid.
	k on	5*108 M–1s–1	ibid.
	D	220 *10–12 m2s–1	ibid.
	κ	3	Calculated
Immobile endogenous Ca2+ buffer (EB)	κ E	25	Tran and Stricker, 2018; Bornschein et al., 2019a
Fast EB	[EBf]	46.5 *10–6 M	Calculated
	K D	2*10–6 M	Vyleta and Jonas, 2014; Bornschein et al., 2019a
	k off	1000 s–1	ibid.
	k on	5*108 M–1s–1	ibid.
	κ E	23.25	Calculated
Slow EB	[EBs]	1.23*10–7 M	Calculated
	K D	7*10–8 M	Nägerl et al., 2000
	k off	0.7 s–1	ibid.
	k on	1*107 M–1s–1	ibid.
	κ E	1.75	Calculated
P/Q-type channel	a, b	247.71, 8.28 ms–1	Li et al., 2007
	α1,0,β1,0	5.89, 14.99 ms–1	ibid.
	α2,0, β2,0	9.21, 6.63 ms–1	ibid.
	α3,0, β3,0	5.2, 132.8 ms–1	ibid.
	α4,0,β4,0	1823.18, 248.58 ms–1	ibid.
	k1	62.61 mV	ibid.
	k2	33.92 mV	ibid.
	k3	135.08 mV	ibid.
	k4	20.86 mV	ibid.
Release sensor models			Bornschein et al., 2025
Syt1 model	k off	10 000 s–1	ibid.
	k on	1*108 M–1s–1	ibid.
	γ	5900 s–1	ibid.
	β	4	ibid.
Syt1 priming model	k off	10 000 s–1	ibid.
	k on	1*108 M–1s–1	ibid.
	γ	4000 s–1	ibid.
	β	4	ibid.
	K M	20*10–6 M	ibid.
	k prim	6000 s–1	ibid.
	n	5	ibid.

^*Corrected for the space occupied by vesicles and organelles (Wilhelm et al., 2014).

^†Assumed to be similar to free Ca²⁺ (Bucurenciu et al., 2008).