Alcohol-deprivation effect in rats genetically selected for their ethanol preference.

Alcohol deprivation and alternate-day access increase voluntary alcohol drinking by normal rat strains in a consistent manner. In contrast, the ANA strain developed by selective outbreeding for low alcohol intake during continuous access showed no increase in their alcohol drinking during alternate-day access and only a small increase after a week of deprivation. The AA strain developed for high alcohol intake showed an increase after a week of deprivation similar in magnitude to that of normal rats but persisting much longer. In order to have been selected, these deviant reactions to deprivation must have been related to deviant baseline levels of alcohol drinking during continuous access, but presently even the AAs with the lowest baselines show the persistent increase and the ANAs with the highest baselines show only small increases. Strain differences were also found in spontaneous alternation in a T-maze. A modification of Pinel and Huang's inhibitory factor model accounting for these results is presented.