Table 2.
Concentration-dependent effects on the kinetics of pentobarbital-induced tail current
| α1β3 | α1c1 | |||||
|---|---|---|---|---|---|---|
| 0·3 mm | 1 mm | 3 mm | 1 mm | 3 mm | 10 mm | |
| τfast (ms) | 66 ± 12 | 135 ± 28 | 166 ± 60 | 74 ± 8 | 109 ± 9 | 156 ± 50 |
| Areafast | 0·58 ± 0·05 | 0·44 ± 0·08 | 0·06 ± 0·03 | 0·27 ± 0·07 | 0·13 ± 0·07 | 0·07 ± 0·03 |
| Δslow (ms) | 390 ± 93 | 491 ± 97 | 664 ± 310 | 1450 ± 93 | 1092 ± 214 | 1149 ± 266 |
| Areaslow | 0·4 ± 0·05 | 0·56 ± 0·08 | 0·94 ± 0·03 | 0·73 ± 0·07 | 0·86 ± 0·07 | 0·91 ± 0·04 |
This table shows the parameters estimated by fitting the tail current observed at different pentobarbital concentrations (0·3–10 mm) with a function consisting of the sum of two exponentials of the type Afastexp[-t/τfast]+Aslowexp[-t/τslow]. Areas were calculated by integrating the area under each component and normalizing it to the total area. Data are means ±s.e.m., calculated from 4 cells in α1β3 and 8 cells in α1c1. Each determination is the average of 3–8 values. Data show a concentration-dependent increase in the time constant of the fast component in both α1β3 and α1c1. However, the largest and most evident concentration-dependent effect is on the area of each component.