| Species | Original | Mutated to | Mutation |
| Human | Trp 55 |
|
|
| Rat Equivalent | Trp 54 | ||
| Mouse Equivalent | Trp 60 | Ser | W60S |
The EC50 and Hill values for the 5-HT3AW60S mutant were not significantly different from those of the wild-type receptor. The mutation had no effect of receptor function.
| Wild Type | W60S | |
| [3H] Granisetron (Kd) | 0.17 +/- 0.003 | 0.21 +/- 0.05 |
| [3H] Granisetron (nH) | 1.03 +/- 0.11 | 0.84 +/- 0.15 |
| [3H] mCPBG (Kd) | 1.48 +/- 0.09 |
1.31 +/- 0.13 |
| [3H] mCPBG (nH) | 1.07 +/- 0.02 | 0.90 +/- 0.06 |
| 5-HT3 (EC50) | 2.10 +/-0.40 | 2.26 +/- 0.21 |
| 5-HT3 (nH) | 2.22 +/- 0.20 | 1.71 +/- 0.14 |