Effects of alcohol deprivation on alcohol consumption using a sipper-tube procedure

Background: When rats with prior experience drinking ethanol solutions are deprived of ethanol for various lime periods, a transitory increase in alco hol consumption is observed when ethanol solutions are again made available . This has been termed the alcohol deprivation effect (ADE). The ADE has be en observed in limited-access operant procedures in which small dippers of ethanol are presented following completion of a lever press requirement. Ho wever, it has not been determined if the effect occurs in an operant model of ethanol self-administration that separates the ethanol-seeking respondin g from the consummatory drinking (the sipper procedure). Methods: Rats were initiated to drink ethanol from a sipper tube using the sucrose-substitution procedure. Once initiated, the rats had to make 30 lev er presses to gain access to a sipper-tube containing the ethanol solution for 20 min. The effects of 2-3 days, 7 days, and 14 days of ethanol depriva tion were examined on ethanol consumption and extinction responding (seekin g response). Results: There were no effects of deprivation on intake at any deprivation period examined. Contrary to expectations, the alcohol-seeking response as measured by extinction responding was decreased after 7 and 14 days of depr ivation. Conclusions: The data from this study and others using the limited access o perant procedures suggest that the ADE may be more related to consummatory control (i.e., loss of control) and not to ethanol-seeking behaviors (i.e., craving).