Table 3.

Active zone topographies.

AZ topgraphy		Release	Chelators	Submaximal Cd2+ block	Full subtype block	References
SINGLE-DOMAIN TOPOGRAPHY (NO DOMAIN-OVERLAP)
	homog. tight coupling all pr identical = nanodomain	pr, avg = 1/N∑pr = pr $F_{syn}={(1-p_r)}^N$ $P_{syn}=1-F=1-{(1-p_r)}^N$	BAPTA >> EGTA DE: Monophasic	PPR→	RRtotal = RRP/Q + RRN	Bucurenciu et al., 2008; Baur et al., 2015; Kusch et al., 2018
	homog. loose coupling all pr identical	Ditto	BAPTA ≥ EGTA DE: Monophasic	Ditto	Ditto	Only simulation
	heterog. coupling heterog. pr	pr, avg = 1/(N1 + N2)(∑pr, 1 + ∑pr, 2) $F_{syn}={(1-p_{r,1})}^{N1}{(1-p_{r,2})}^{N2}$ Psyn = 1−F	BAPTA ≥ EGTA DE: Biphasic	Ditto	Ditto	Scimemi and Diamond, 2012; Ritzau-Jost et al., 2018
DOMAIN-OVERLAP TOPOGRAPHY
	heterog coupling homog. pr	Catotal = Ca1 + Ca2 Catotal → pr	BAPTA ≥ EGTA DE: Monophasic	PPR↗	RRtotal < RRP/Q + RRN	Ermolyuk et al., 2013
	homog. tight coupling homog.pr	Catotal = nCa Catotal → pr	BAPTA >> EGTA DE: Monophasic	Ditto	Ditto	Nakamura et al., 2015
	homog. loose coupling homog. pr = microdomain	Ditto	BAPTA ≥ EGTA DE: Monophasic	Ditto	Ditto	Vyleta and Jonas, 2014; Baur et al., 2015; Nakamura et al., 2015; Kusch et al., 2018

p_r, release probability of a vesicle; N, number of vesicles (or release sites that can release a max. of one vesicle), p_r,avg, average release probabilities across vesicles; P_syn, synaptic release probability, F_syn, synaptic failure rate; DE, EGTA dose effect curve; PRR, paired-pulse ratio; RR, release rate.