Table 2. Single-channel properties of GIRK2 wild-type and mutant channels.
| GIRK2 | Y102N | F147Y | N184D | |
|---|---|---|---|---|
| Channel opening probability, % | 0.34 ± 0.13 | 1.08 ± 0.39 | 0.33 ± 0.09 | 1.56 ± 0.47* |
| Opening frequency, s-1 | 3.68 ± 1.00 | 5.50 ± 2.04 | 4.36 ± 0.85 | 9.02 ± 2.07* |
| Mean open duration, ms | 0.67 ± 0.14 | 1.82 ± 0.19*** | 0.50 ± 0.10 | 1.45 ± 0.17** |
| Mean closed duration, ms | 453.3 ± 119.8 | 459.3 ± 183.1 | 309.5 ± 73.93 | 162.0 ± 33.64* |
| No. of patches | 8 | 7 | 6 | 8 |
| No. of openings | 4,346 | 5,675 | 4,863 | 9,144 |
Single-channel recordings were made from cell-attached patches from Xenopus oocytes injected with cRNAs encoding for GIRK2 wild-type and mutant channels. Patch membrane potential was clamped at -100 mV. Comparisons were made by performing one-way analysis of variance on data obtained from GIRK2, Y102N, F147Y, and N184D GIRK2 channels followed by Bonferroni's multiple-comparison tests. Data are presented as mean ± SEM. Significance levels are: ***, P < 0.0005; **, P < 0.005; *, P < 0.05; other values are not significantly different from wild type.