DYSPHORIC-LIKE BEHAVIOUR DURING ETHANOL WITHDRAWAL IN FEMALE RATS. EFFECT OF CONTINUOUS VS INTERMITTENT ACCESS PARADIGM.

Abstract

Women show higher vulnerability for neuroadaptation to alcohol, which may contribute to negative emotional state during withdrawal (Sharrett-Field et al., 2013; Koob and Le Moal, 1997). This study aimed at exploring the effects of different patterns of voluntary ethanol consumption on female rat"s affective behaviour during withdrawal. Female rats underwent 12-week-, 2-bottle choice- continuous or intermittent (3 days/week ) access to 20% ethanol and were respectively named CARs and IARs. They were tested for alcohol preference; dysphoric-like state during withdrawal (24-48h); depressive- and anhedonic-like behaviours explored by forced swim- and saccharin preference tests; anxiety-like behaviour by the EPM and behavioural reactivity in the OF arena. During the 12-week self-administration procedure, IARs displayed higher ethanol consumption and preference, both after 1h and 24h, with respect to CARs (p<0.001). During abstinence, both groups displayed increased immobility in forced-swim test and decreased preference for saccharin, when compared to controls (p<0.01); furthermore, IARs showed a lower saccharin preference than CARs (p<0.001). CARs significantly reduced open arm time and entries in the EPM (p<0.05), while IARs increased central preference (p<0.01), as well as time spent in the central arena in open field (p<0.05), with respect to controls. These data suggest that specific drinking pattern differently affects female rat behaviour during ethanol withdrawal. As reported for males, intermittent ethanol consumption in female rats failed to determine anxiety-like signs during withdrawal, while it induced dysphoric-like conditions characterized by anhedonic- and depressive-like behaviours.