Rodents, too, show elevated corticosterone (analogous to human cortisol), prolactin, and beta-endorphin, after an alcohol injection. Rats genetically selected for high alcohol preference (AA) have been shown to have a blunted corticosterone response to a high dose of alcohol compared to a line selected for low preference (ANA), but only under conditions of social isolation (Apter, Eriksson 2006). AA rats showed greater POMC levels than non-drinking ANAs, and lower baseline beta-endorphin release, but the two lines did not differ in alcohol-stimulated release (De Waele et al. 1994). However, the HPA-system does appear to regulate alcohol-intake by the AA, but not ANA, rat: adrenalectomy, and corticosterone replacement, altered alcohol intake in AA, but not ANA, rats (Fahlke, Eriksson 2000). In P rats, lower levels of CRF were found in the amygdala, hypothalamus, prefrontal cortex, and cingulate cortex, compared with NP rats (Ehlers et al. 1992). In sP rats, higher levels of serum corticosterone have been reported, compared with sNP rats, suggesting differences in HPA activity (Bano et al. 1998). An examination of the data from selected mouse lines revealed that WSP
