Table 2:

Concentration–response relationships of menthol stereoisomers on (α4)3(β2)2 and (α4)2(β2)3 nAChRs

nHIC50 (μm)nImax (μA)
1:10 (α4)2(β2)3 a
    (–)-Menthol−0.71 ± 0.0244.9 ± 1.62100.08–1.34
    (+)-Menthol−0.90 ± 0.0348.3 ± 1.67c100.12–0.97
10:1 (α4)3(β2)2 b
    (–)-Menthol−0.81 ± 0.0333.1 ± 1.83100.09–1.30
    (+)-Menthol−0.85 ± 0.0345.5 ± 2.03d100.13–1.37

  • ↵a Stimulated with 2 µm ACh.

  • ↵b Stimulated with 100 µm ACh.

  • ↵c p = 0.033, IC50 of (−)-menthol vs. (+)-menthol on (α4)2(β2)3 nAChRs.

  • ↵d p = 0.0001, IC50 of (−)-menthol vs. (+)-menthol on (α4)2(β2)3 nAChRs.