The role of the α7 subunit, encoded by the CHRNA7 gene, in nicotine dependence or withdrawal is not fully understood, and studies have found few differences in the effects of nicotine between α7 KO and wild-type mice (Davis and Gould 2007; Walters et al. 2006). Damaj et al. (2003) found that α7 nAChRs contribute to some nicotine withdrawal signs, but Grabus et al. (2005) and Markou and Paterson (2001) found that methyllycaconitine (MLA), an α7 nAChR antagonist, did not precipitate withdrawal.
