Sensitivity to appetitive and aversive effects of ethanol in infant rats classified as high or low novelty-seekers

MS FERNÁNDEZ; N SANCHEZ; ABATE P; PAUTASSI RM

Huerta Grande

Congreso; Congreso Anual 2012 de la Sociedad Argentina de Investigación en Neurociencias; 2012

Sociedad Argentina de Neurociencias

The association between novelty-seeking and ethanol´s motivational effects was tested in infant rats. Hypothesis: High responders will be more sensitive to ethanol?s appetitive effects and less sensitive to ethanol-induced aversion. Experiments 1 and 2: Pups were classified as high or low responders as a function of locomotion in an open field. At postnatal day 14 (PD14) pups received 0.0, 0.5 1.0 or 2.0 g/kg ethanol (i.g., unconditional stimulus, US), paired with water (Conditional stimulus, CS1). At PD15, the CS1 was paired with sandpaper (CS2). In test, animals previously treated with 2.0 g/kg ethanol group avoided sandpaper and those given 0.5 g/kg exhibited preference for the CS. Exp 3: Animals were classified as high or low seekers for a novel odor (PD14). At PDs15-16 saccharin was paired with 0, 1.25 or 2.5g/kg ethanol. A decrement in saccharin intake was observed on PD 17, in animals given 2.5 g/kg ethanol. Across experiments ethanol motivational effects were not modulated by novelty-seeking. Infant were highly sensitive to ethanol-induced motivational learning, yet this response was not associated with proclivity to explore new stimuli.