TABLE 2

Comparisons of the Bmax and Kd values for nAChRs in rat retina measured with four radioligands and comparison of values in the retina and cerebral cortex measured with [3H]EB The Bmax and Kd values were derived from nonlinear, least-square regression analyses applied to saturation curves, as shown in Fig. 2. Data are the mean ± S.E.M. from 2 to 10 independent saturation curves. One-way analysis of variance followed by Bonferroni's multiple comparison test found that the Bmax value for [3H]EB is significantly higher than those for [125I]A-85380, [3H]cytisine, and [3H](–)nicotine in the retina.

LigandRetinaCortex
KdBmaxKdBmax
nM fmol/mg protein nM fmol/mg protein
[3H]EB 0.092 ± 0.02 204 ± 5.2 0.10 ± 0.0065 64.3 ± 1.2
125I-A85380 0.085 ± 0.02 152 ± 18**
[3H]Cytisine 0.40 ± 0.017 82.6 ± 1.9***
[3H](–)Nicotine 4.3 ± 0.49 94.7 ± 6.7***
  • ** p < 0.01

  • *** p < 0.001