Table 1

nAChR binding properties of ABT-594, A-98593, (±)-epibatidine and (−)-nicotine

CompoundKi
[3H](−)Cytisine[125I]α-Btx
Rat brain α4β2Human α4β2Rat brain α7Human α7Torpedo α1β1δγ
nM nM
ABT-5940.037  ± 0.0030.055  ± 0.00513,800  ± 3901,560  ± 17010,000  ± 500
A-985930.039  ± 0.0030.034  ± 0.0054,620  ± 1171,780  ± 3403,420  ± 1600
(±)-Epibatidine0.043  ± 0.0060.07  ± 0.01230  ± 920.6  ± 42.7  ± 0.8
(−)-Nicotine1.0  ± 0.021.0  ± 0.094,000  ± 8907,130  ± 780>1,000

Receptor binding studies were performed as described under “Materials and Methods.” Results are the means ± S.E.M. of three to five separate determinations. The Hill coefficients were not significantly different from unity in all cases (data not shown).