TABLE 3

pEC50 and Imax values of neonicotinoids and DN-IMI for the wild-type and mutant chicken α7 nicotinic acetylcholine receptors expressed in Xenopus laevis oocytes

LigandsWild-TypeSer58Lys MutantGln79Arg MutantSer58Lys;Gln79Arg Mutant
pEC50aImaxapEC50ImaxpEC50ImaxpEC50Imax
Acetylcholine3.82 ± 0.071.22 ± 0.051.82 ± 0.172.41 ± 0.392.63 ± 0.051.11 ± 0.032.14 ± 0.041.62 ± 0.06
Imidacloprid3.67 ± 0.080.51 ± 0.03NDb23.1 ± 1.5c4.02 ± 0.101.48 ± 0.114.16 ± 0.164.48 ± 0.45
Clothianidin3.42 ± 0.180.16 ± 0.033.44 ± 1.371.72 ± 0.163.55 ± 0.051.04 ± 0.053.70 ± 0.092.84 ± 0.19
Thiacloprid4.38 ± 0.170.49 ± 0.054.11 ± 0.103.15 ± 0.203.89 ± 0.060.30 ± 0.014.36 ± 0.175.53 ± 0.52
CH-IMI4.42 ± 0.161.43 ± 0.124.67 ± 0.1024.7 ± 1.24.89 ± 0.163.13 ± 0.215.02 ± 0.288.72 ± 0.95
DN-IMI5.46 ± 0.091.00 ± 0.044.02 ± 0.032.45 ± 0.074.39 ± 0.050.67 ± 0.023.99 ± 0.020.69 ± 0.02
(−)-Nicotine4.93 ± 0.030.88 ± 0.023.69 ± 0.050.15 ± 0.013.71 ± 0.070.35 ± 0.023.58 ± 0.140.10 ± 0.01
  • a All of the data were newly measured. pEC50 is −log EC50 [half maximal effective concentration (M)], whereas Imax is the normalized maximal response. Data are presented as means ± S.E. of four to six replicates.

  • b Could not be determined because the concentration-response curve did not reach a maximum.

  • c Imax was determined at 3 mM.