Table 1.

Endocytosis after stimulation

Pipette solution Stimulus (cell number) ΔCmnet (fF) Afast (fF) τfast (S) τslow (S)
Control
1 pulse (9) 473 12.0
10 pulses at 10 Hz (11) 1287 407 1.4 18.4
10 pulses at 1 Hz (7) 1607 217 1.1 23.0
10 pulse (+75 mV) at 1 Hz (5) 805 19.0
50 AP-e at 100 Hz (7) 710 16.4
200 AP-e at 100 Hz (6) 1362 337 1.9 19.6
5 × 50 AP-e (100 Hz) at 1 Hz (8) 1344 284 1.4 18.8
5 × 50 AP-e (30 Hz) at 1 Hz (8) 735 136 1.3 18.0
10 mm EGTA
10 pulses at 1 Hz (4) 850 14.3
200 AP-e at 100 Hz (6) 756 16.3
  • After stimulation, the capacitance jump (ΔCmnet) decayed with either a monoexponential or a biexponential function as judged by eyes. The pulse refers to a 20 ms depolarization by 90 mV. The monoexponential decay was fit with the equation A(t) = ΔCmnet × exp (t/slow), and the biexponential decay was fit with the equation A(t) = Afast × exp (t/fast) + Aslow × exp (t/slow), where Afast and Aslow are the amplitude of the fast and slow component of endocytosis, respectively, and τfast and τslow are the time constants of the fast and slow component of endocytosis, respectively. Because the net capacitance increase after stimulation (ΔCmnet) is the sum of Afast and Aslow, Aslow is not shown in the table. Either 0.05 mm BAPTA (Control) or 10 mm EGTA was included in the pipette. The values are the mean value.