Läck et al. 2005). Increases in NR2B, and to a lesser extent NR2A, protein expression have also been observed using immunologic techniques after both in vitro and in vivo EtOH exposure (Kash et al. 2005; Obara et al. 2009; Snell et al. 1996). However, other investigators did not observe increased expression of this protein. Increased expression of mRNA and protein for other NR subunits and particular NR1 splice variants has been observed in some brain regions following chronic EtOH exposure (Raeder et al. 2008; Trevisan et al. 1994; Roberto et al. 2006; Winkler et al. 1999, but see Morrow et al. 1994), but there is less evidence for increased receptor function as a result of these increases. Thus, it is not clear whether increased subunit expression is the driving force behind increased receptor function, and if so, what mechanisms underlie the increase in expression or trafficking.
