Allosteric properties of hM3 receptors with mutations at Phe222
The parameters pKapp and Hill slope (nH) represent best-fit values ± S.E. from global curve fitting to the combined data of three or more assays. Data for wild-type hM3 receptors were included for comparison. Statistical significance was determined by F test, either between or within data sets (see Materials and Methods). The between-set P values shown are for comparisons with the immediate parental receptor, hM3. When nH was found to be significantly (P < 0.05) different from the parental receptor (or when there was no parental receptor), a global F test was also carried out to determine whether nH differed from the standard (unit) slope.
Receptor | pKapp and F Test | Hill slope (nH) and F Tests | ||||||
|---|---|---|---|---|---|---|---|---|
| pKapp | vs Parental | nH | vs Parental | vs Unity | ||||
| THA | ||||||||
| hM3 | 4.90 ± 0.02 | 1.89 ± 0.13 | <0.0001 | |||||
| hM3 F222A | 4.52 ± 0.06 | <0.0001 | 1.37 ± 0.16 | 0.0220 | 0.0225 | |||
| hM3 F222Y | 4.91 ± 0.03 | 0.7285 | 2.36 ± 0.27 | 0.0802 | ||||
| Gallamine | ||||||||
| hM3 | 5.02 ± 0.03 | 1.21 ± 0.09 | 0.0107 | |||||
| hM3 F222A | 4.42 ± 0.04 | <0.0001 | 0.89 ± 0.06 | 0.0406 | 0.0705 | |||
| hM3 F222Y | 5.21 ± 0.05 | 0.0233 | 0.98 ± 0.09 | 0.1068 | ||||
| W84 | ||||||||
| hM3 | 5.79 ± 0.03 | 1.10 ± 0.07 | 0.1391 | |||||
| hM3 F222A | 5.26 ± 0.06 | <0.0001 | 0.92 ± 0.09 | 0.0929 | ||||
| hM3 F222Y | 6.37 ± 0.06 | <0.0001 | 0.96 ± 0.10 | 0.2620 |
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