Increased alcohol intake after prenatal alcohol exposure in the rat: A conditioned response.

CHOTRO, M.G; ARIAS, C

Capri - Italia

Congreso; International Behavioral Neuroscience Society (IBNS); 2002

International Behavioral Neuroscience Society (IBNS)

Previous studies have shown that the administration of a moderate alcohol dose during gestational days (GD) 17-20 in the rat results in enhanced alcohol consumption by the offspring. During this last gestational period the rat fetus can perceive chemosensory characteristics of substances present in the amniotic fluid and these experiences may modify their preference for those flavors through associative or non-associative processes. It is also known that at this stage the opioid system is functional, that the opioid antagonist Naloxone can modify fetal responses known to be regulated through this system, and that opiate antagonists may reduce reinforcing properties of alcohol. Considering this information, it was hypothesized that the increased alcohol consumption after prenatal ethanol exposure could obey to a conditioned preference resulting from the association between sensory and reinforcing properties of alcohol mediated by the opioid system. The associative nature of the effect was tested in a series of three experiments. In Experiment 1, with the aim of interfering with the establishment of the association, pregnant dams received an injection of Naloxone together with the alcohol administration during GD 17-20. In Experiment 2 subjects were exposed prenatally to alcohol and during postnatal days 10-12 were re-exposed only to the sensory properties of alcohol, in order to extinguish the association. In the last experiment, subjects were exposed prenatally to alcohol and postnatally were aversively conditioned to alcohol taste. Results suggest that the opioid system plays an important role in the augmented alcohol intake effect observed after prenatal alcohol exposure. Also seem to support the hypothesis of a conditioned preference response established in utero after maternal alcohol administration.