Although not identified by the GO or Ingenuity® analyses, Crh gene expression was increased in the chronic ethanol drinking P rats of the present study and has been implicated in substance abuse (c.f., Heilig and Koob, 2007; Koob and Le Moal, 2008). For example, (a) Crh knockout mice display greater ethanol preference and limited access ethanol intake than their wild-type counterparts (Olive et al., 2003); (b) Crh over-expressing mice display lower ethanol preference and reduced 24-hr ethanol intake than their wild-type counterparts (Palmer et al., 2004); (c) chronic ethanol drinking increases preproCrh mRNA in the CNS of Sprague-Dawley rats (Lack et al., 2005); and (d) Crh levels predict intensity of craving and probability of relapse to drug use after acute detoxification (Kiefer and Wiedemann, 2004; see also Goeders, 2002a, 2002b).
