Inhibitory potency of PhTX-74 at recombinant AMPAR subtypes in the presence and absence of the TARP γ-2
| Receptor Subtype | Coexpressiona | IC50b |
|---|---|---|
| nM | ||
| GluA1 | – | 296 [266–331] |
| GluA1 | γ-2 | 356 [319–399] |
| GluA2R | – | N.D. |
| GluA2R | γ-2 | >100,000 |
| GluA3 | – | 263 [228–305] |
| GluA3 | γ-2 | 252 [229–279] |
| GluA1/A2R | – | 52,150 [44,650–60,900] |
| GluA1/A2R | γ-2 | 21,960 [16,620–29,030]* |
| GluA2R/A3 | – | 48,730 [40,050–59,290] |
| GluA2R/A3 | γ-2 | 22,610 [19,140–26,710]* |
N.D., not determined.
↵a Coexpression with γ-2 is described in Materials and Methods.
↵b IC50 values were determined by the nonlinear fitting of concentration-inhibition data collected in 6–10 oocytes held at −80 mV (see Materials and Methods). Numbers in brackets denote the 95% confidence interval for IC50.
↵* P < 0.01 versus receptor subtype expressed in absence of γ-2 (unpaired t test with Welch's correction).