within a specific region, in GIRK2 knockout mice supports this contention, as has also been suggested previously (Koyrakh et al., 2005; Liao et al., 1996; Torrecilla et al., 2002). Nevertheless, the expression of GIRK2 does not preclude the formation of signalling complexes that do not contain the GIRK2 subunit, as we know that neurons produce more than one type of GIRK channel (Luján et al., 2009). This is clearly illustrated in the cerebellum by the existence of GIRK channels that do not contain the GIRK2 subunit (Aguado et al., 2008). Therefore, regional differences in the expression of GIRK subunits may serve as an indicator for the presence of distinct GIRK channel subtypes. This is important because differential subunit assembly can confer distinct GIRK channel properties (Duprat et al., 1995; Krapivinsky et al., 1995).
