Table 1.

The potencies of S-mTFD-MPPB, R-mTFD-MPPB, and proadifen as modulators of [³H]ACh, [³H]TCP (+Carb), and [³H]tetracaine (+α-bungarotoxin) equilibrium binding to Torpedo nAChRs

For each independent equilibrium binding assay, binding at each modulator concentration was determined in duplicate, and the specific binding at each concentration was normalized to the total specific binding in the absence of modulator. n, number of independent experiments; ND, not determined.

Ligands	[3H]ACh			[3H]TCP		[3H]Tetracaine
	EC50	Emax	n	IC50	n	IC50	n
	μm	%		μm		μm
S-mTFD-MPPB	6.4 ± 2.3	118 ± 2	4	6.6 ± 0.9	5	>1000	2
R-mTFD-MPPB	7.6 ± 2.8	119 ± 1	2	3.1 ± 0.3	2	408 ± 27	2
Proadifen	0.95 ± 0.40	130 ± 6	4	ND	ND	ND	ND