Comparison of amperometric events from control neurons and neurons exposed to GDNF or 20 μm l-DOPA for 30 min (mean ± SEM)
| Number of molecules (mean) | Number of molecules (mode) | imax(pA) | t1/2 (μsec) | Width (μsec) | |
|---|---|---|---|---|---|
| Control | 3000 ± 300 | 2300 | 14.6 ± 1.4 | 120 ± 40 | 180 ± 40 |
| GDNF | 11,400 ± 700 | 4300 | 26.8 ± 1.6 | 130 ± 80 | 430 ± 50 |
| 20 μm l-DOPA | 10,600 ± 400 | 5400 | 23.7 ± 1.0 | 130 ± 10 | 370 ± 20 |
imax represents maximum amplitude,t1/2 the width at half height, and the width the duration of the event. Controls represent n = 69 events (20 sites); the 20 μm l-DOPA-treated group representsn = 295 events (9 sites); the GDNF-treated group represents n = 109 events (14 sites). Five large outlying events (see Results) and apparent overlapping events (e.g., rightmost pair of Figure 2B, bottom expansion) are not included. GDNF and l-DOPA increased the mean quantal size to 380 and 350% of control levels, and both were significantly different from controls (p < 0.0001 in both cases; KS-Z = 3.027, KS-Z = 5.0931, respectively). GDNF and l-DOPA increased the maximum amplitude (p < 0.0001; KS-Z = 4.0202 and KS-Z = 4.6264, respectively) and width (p < 0.0001; KS-Z = 2.9962, KS-Z = 4.8912, respectively). The modal values of the quantal size are smaller than the means because of the right-hand skew of untransformed quantal size populations. The population distribution of the same events is displayed in Figure6D.