The developing fetus and infant under alcohol-related challenges: Reasons behind a pharmacological imprinting.

MOLINA, JC

CONCEPCION

Conferencia; I LASBRA-LARNEDA Joint Meeting on Alcohol and other Drugs of Abuse: From molecules to human disorders; 2013

Latin American Society for Biomedical Research on Alcoholism

Preclinical and epidemiological studies indicate a significant association between early alcohol experiences and subsequent affinity for the drug. Early learning processes involving ethanol, meet different criteria that define the phenomenon of imprinting. A sensitive learning period appears to cover the stages of late gestation and neonatal life. Within this time period, experimental evidences indicate heightened central sensitivity to the motivational effects of ethanol´s principal metabolite (acetaldehyde) and resistance to peripheral aversive effects of the drug. In addition, minimal exposure to ethanol´s chemosensory cues facilitate subsequent recognition of these stimuli and the possibility of associative learning comprising ethanol´s motivational properties. Beyond the specificity of ethanol-related sensitivity, the neonate also exhibits learning particularities that lead to appetitive memories despite the use of aversive stimuli such as maternal maltreatment. The drug abruptly disrupts maternal care; a phenomenon that triggers stress-related responses in the progeny which in turn promote alcohol self-administration. Learning derived from fetal and/or neonatal sensitivity to ethanol´s reinforcing effects and ethanol-derived experiences during lactation, merge and configure memories that promote alcohol preference and drug seeking behaviors. Some of these findings have already been observed in human neonates whose mothers exhibited moderate drinking during pregnancy. As a whole, these results strengthen two basic ideas: a) alcohol use and abuse can be determined through early developmental experiences comprising the drug and b) it is difficult to sustain the notion of ?safe? alcohol doses during fetal and infantile life due to the likelihood of learning that has a significant impact upon future drinking patterns.