TABLE 2.
Functional effects of Ala and conserved substitutions at the 5-HT3 receptor
| Alanine mutant | pEC50 Mean ± SE | EC50 (μM) | n | Conserved mutant | pEC50 Mean ± SE | EC50 (μM) | n |
|---|---|---|---|---|---|---|---|
| Wild-type | 6.62 ± 0.06 | 0.24 | 12 | Wild-type | 6.62 ± 0.06 | 0.24 | 12 |
| S177A | NR* | — | 4 | S177T | NR* | — | 4 |
| L178A | NR* | — | 4 | L178I | NR* | — | 4 |
| T179A | NR* | — | 4 | T179S | NR* | — | 4 |
| F180A | NR* | — | 4 | F180Y | NR* | — | 4 |
| T181A | 5.86 ± 0.08* | 1.38 | 4 | T181S | NR* | — | 6 |
| S182A | NR* | — | 4 | S182T | 6.21 ± 0.07 | 0.62 | 4 |
| W183A | 4.40 ± 0.11* | 39.8 | 6 | W183Y | 5.28 ± 0.26* | 5.25 | 6 |
| L184A | 4.47 ± 0.07* | 33.9 | 4 | L184I | 5.47 ± 0.17* | 3.39 | 4 |
| H185A | NR* | 4 | H185N | NR* | — | 4 | |
| T186A | 4.24 ± 0.03* | 57.5 | 6 | T186S | NR* | — | 4 |
| I187A | 4.65 ± 0.07* | 22.4 | 4 | I187L | 5.48 ± 0.10* | 3.31 | 4 |
| Q188A | NR* | 4 | Q188N | NR* | — | 4 | |
| D189A | NR* | 4 | D189E | NR* | — | 4 | |
| I190A | NR* | 4 | I190L | 6.33 ± 0.01 | 0.47 | 4 | |
| N191A | NR* | 4 | N191Q | NR* | — | 4 |
*
Significantly different to wild-type (ANOVA with Dunnett's post test: p < 0.05). NR, No response.