Table 1.

Kinetics of endocytosis after a brief stimulus

	Control	0.5 mM EGTA	0.4 mM BAPTA	EGTA-AM	2 mM EGTA	2 mM BAPTA
Afast (%)	100	100	100	64	49	38
τfast (s)	1.2	1.3	1.7	2	1.2	0.6
τslow (s)	—	—	—	14	11	13
n	10	6	15	16	10	9

The averaged time courses of the capacitance responses after a 20-ms depolarization were fit with the equation A(t) = A_fast⋅exp(−t/τ_fast) + A_slow⋅exp(−t/τ_slow). n is the number of terminals. Controls were recordings made by using the perforated patch technique without the addition of EGTA or BAPTA. In control terminals and terminals dialyzed with 0.5 mM EGTA or 0.4 mM BAPTA, the fall in capacitance could be described as a single exponential so the averaged record was fit with the equation A(t) = A_fast⋅exp(−t/τ_fast).