Table 1.

Competition binding constants for SPX and GYM with muscle-type and neuronal nAChRs expressed in HEK293 cells

	Ki ± SEM, nM*
Ligand	α12βγδ (Torpedo)	α4β2 (Human)	α3β2 (Human)
SPX	0.080 ± 0.002	0.58 ± 0.07	0.021 ± 0.005
GYM	0.23 ± 0.08	0.62 ± 0.07†	0.24 ± 0.09†

*Mean values ± SEM from three distinct experiments performed in duplicate.

^†Calculated from IC₅₀ values reported in ref. 15.