Effects of Alcohol and Saccharin Deprivations on Concurrent Ethanol and Saccharin Operant Self-Administration by Alcohol-Preferring (P) Rats

Abstract

Consumption of sweet solutions has been associated with a reduction in withdrawal symptoms and alcohol craving in humans. The objective of the present study was to determine the effects of EtOH and saccharin (SACC) deprivations on operant oral self-administration. P rats were allowed to lever press concurrently self-administer EtOH (15% v/v) and SACC (0.0125% g/v) for 8 weeks. Rats were then maintained on daily operant access (non-deprived), deprived of both fluids (2 weeks), deprived of SACC and given 2 ml of EtOH daily, or deprived of EtOH and given 2 ml of SACC daily. All groups were then given two weeks of daily operant access to EtOH and SACC, followed by an identical second deprivation period. P rats responded more for EtOH than SACC. All deprived groups increased responding on the EtOH lever, but not on the SACC lever. Daily consumption of 2 ml EtOH decreased the duration of the ADE. Home cage access to 2 ml SACC also decreased the ADE but to a lesser extent than access to EtOH. A second deprivation period further increased and prolonged the expression of an ADE. These results show EtOH is a more salient reinforcer than SACC. With concurrent access to EtOH and SACC, P rats do not display a saccharin deprivation effect. Depriving P rats of both EtOH and SACC had the most pronounced effect on the magnitude and duration of the ADE, suggesting that there may be some interactions between EtOH and SACC in their CNS reinforcing effects.