INIMEC - CONICET   05467
INSTITUTO DE INVESTIGACION MEDICA MERCEDES Y MARTIN FERREYRA
Unidad Ejecutora - UE
artículos
Título:
Ethanol induces second-order aversive conditioning in adolescent and adult rats.
Autor/es:
PAUTASSI, RM; MYERS, M.L.; SPEAR, LP; MOLINA, JC; SPEAR, NE
Revista:
ALCOHOL
Editorial:
ELSEVIER SCIENCE INC
Referencias:
Año: 2010 vol. 45 p. 45 - 55
ISSN:
0741-8329
Resumen:
Alcohol abuse and dependence are considered public health problems, with
an etiological onset often occurring during late childhood and
adolescence, and understanding age-related differences in ethanol
sensitivity is important. Low to moderate ethanol doses (0.5 and 2.0
g/kg, intragastrically [i.g.]) induce single-trial, appetitive
second-order place conditioning (SOC) in adolescent, but not adult,
rats. Recent studies have demonstrated that adolescents may be less
sensitive than adults to the aversive properties of ethanol, reflected
by conditioned taste aversion. The present study assessed the aversive
motivational effects of high-dose ethanol (3.0 and 3.25 g/kg, i.g., for
adolescents and adults, respectively) using SOC. Experiment 1 revealed
similar blood and brain ethanol levels in adolescent and adult rats
given 3.0 and 3.25 g/kg ethanol, respectively. In Experiment 2, animals
received ethanol or vehicle paired with intraoral pulses of sucrose
(conditioned stimulus 1 [CS1]). After one, two, or three conditioning
trials, the rats were presented with the CS1 while in a distinctive
chamber (CS2). When tested for CS2 preference, ethanol-treated animals
exhibited reduced preference for the CS2 compared with controls. This
result, indicative of ethanol-mediated aversive place conditioning, was
similar for adolescents and adults; for females and males; and after
one, two, or three training trials. In conjunction with previous
results, the present study showed that, in adolescent rats subjected to
SOC, ethanol's hedonic effects vary from appetitive to aversive as the
ethanol dose increases. Adolescent and adult animals appear to perceive
the postingestive effects of high-dose ethanol as similarly aversive
when assessed by SOC.