TABLE 2

Inhibition by NNN, NNK, and cotinine

The table summarizes the modulatory effects of nicotine metabolites NNN, NNK, and cotinine. NNN (100 μM), NNK (100 μM), or cotinine (1 mM) were coapplied with ACh (at EC20). The values are mean ± S.D. of control currents from five to eight cells for each condition. The statistical significance applies to comparison with control currents.

ReceptorNNNNNKcotinine
%
α3β492 ± 10†92 ± 12†53 ± 9***
α3β4α596 ± 11†96 ± 4†60 ± 10***
α3β4α5(Asn398)88 ± 5**95 ± 2**52 ± 12***

  • ↵† Not significant.

  • ↵** P < 0.01.

  • ↵*** P < 0.001.