Characteristics of single cell responses from dark-adapted rods with and without Gγ 1
| Dark current (pA) | Dim flash time to peak (ms) | τ rec (ms)a | Integration time (ms) | Io (photons · μm−2)b | Cellular noise ς 2 (pA2)c | Amplification constant (s−2) | |
|---|---|---|---|---|---|---|---|
| Gγ 1 −/− | 9.9 ± 0.9 (n = 12) | 102 ± 15 (n = 12) | 142 ± 15 (n = 12) | 193 ± 24 (n = 12) | 3991 ± 471 (n = 12) | 0.00927 ± 0.00336 (n = 9) | 0.367 ± 0.043 (n = 12) |
| WT | 13.6 ± 0.7 (n = 29) | 114 ± 6 (n = 19) | 174 ± 11 (n = 19) | 254 ± 19 (n = 19) | 59.4 ± 3.0 (n = 19) | 0.0575 ± 0.0199 (n = 8) | 8.87 ± 0.55 (n = 17) |
↵aτrec was determined by fitting a single-exponential function to the final falling phase of the dim flash response.
↵bFlash strength (500 nm) that elicited a half-maximal response.
↵cNoise variance for individual cells was calculated by integrating difference (dark − light) power spectra over a bandwidth of 0.1–20 Hz. All other parameters were determined as by Krispel et al. (2003).