The effect of acute and chronic exposure to ethanol on the developing encephalon: a review

Abstract

OBJECTIVES: to compare the acute and chronic effects of ethanol on the neural development, by analysis of the ontogenetic neural structure of mammals. METHODS: searches were performed in the following electronic databases: MEDLINE, SciElo, PubMed, LILACS, CAPES periodical, and the Open Journal System. The descriptors used were: "chronic ethanol toxicity", "chronic alcohol toxicity", "acute ethanol toxicity", "acute alcohol", "neural ontogenic development", "neuronal migration disturbances", "neural structure". The following inclusion criteria were used: articles published between 2003 and 2007, some classic articles in the field and an important neuropsychology textbook. RESULTS: the analysis of papers revealed that, although several studies of the chronic effects of ethanol exposure on the mammalian nervous system have been conducted, only a few have investigated the acute effects of ethanol on specific days of gestation, and these studies have revealed important disorders relating to the cerebral tissue. CONCLUSIONS: it should be recommended that women refrain from the consumption of ethanol during gestational phase to protect the fetus' health. Furthermore, the acute consumption of ethanol by women nearing the eighth or ninth week of gestation has been shown to be potentially harmful to the nervous tissue of the fetus.

Immunohistochemical Study of Acute Effects of Ethanol on Midbrain of Wistar Rats Associated with the Date of Birth of Neurons in Encephalon

“…Other days of gestation else than E12 should be studied, because only a few references (Aversi-Ferreira et al, 2004;AversiFerreira & Penha-Silva;Souza et al;Aversi-Ferreira & Nascimento) on this topic were currently found in literature.…”

“…The pre-natal exposure to ethanol is responsible for a series of fetal disturbances and malformations, which could result in severe anatomy-physiological effects in the newborn characterizing a disease known as Fetal Alcohol Syndrome (Shetty et al, 1992;Miller, 1993;Valles et al, 1996;VelezDomingues;Aversi-Ferreira et al, 2004;Aversi-Ferreira & Nascimento). This syndrome is characterized by microencephaly, loss of selectivity of neuronal cells, decrease on the density of projections, cell death, aberrations in migration, among others (Miller;Valles et al;Liesi, 1997).…”

“…The deleterious effects of fetal alcohol syndrome refers to the chronic exposure to ethanol, already fairly well known (Aversi-Ferreira & Penha-Silva), but recent studies have shown that even the acute exposure in E12 (twelfth day of the intrauterine life development), which corresponds to the date of birth of neurons in the neocortex of rats and, putatively, the thirtieth day in humans female, generates damage similar to the chronic effects on the prefrontal cortex, on the neocortex in general and on the olfactory bulb (AversiFerreira et al, 2004;AversiFerreira et al, 2005;Aversi-Ferreira et al, 2006;Aversi-Ferreira & Nascimento). However, these effects were not observed on the cerebellum, since the neurons in this region have their date of birth in E10 (Souza et al, 2006); therefore, the doses of ethanol did not affect the formation of the cerebellum neuroblasts.…”

Perfil das Gestantes Usuárias de Álcool/Drogas e os Efeitos na Saúde e Desenvolvimento dos Filhos

“…Estudos como este são de suma importância para avaliar o desenvolvimento após a infância dos filhos de mães que fizeram uso de álcool e/ou drogas ilícitas durante a gestação. A exposição pré-natal ao álcool causa anomalias severas no desenvolvimento do córtex cerebral e o desenvolvimento anormal do cérebro pode resultar em distúrbios funcionais na idade adulta (Aversi-Ferreira & Nascimento, 2008;Yamaguchi et al, 2008).…”

“…De forma complementar, estudos de revisão indicam que a exposição pré-natal ao álcool causa anomalias severas no desenvolvimento do córtex cerebral e o desenvolvimento anormal do cérebro pode resultar em distúrbios funcionais na idade adulta (Aversi-Ferreira & Nascimento, 2008;Yamaguchi, Cardoso, Torres, & Andrade, 2008). A Síndrome Alcoólica Fetal (SAF) é a consequência mais séria para o feto após o consumo de álcool durante a gestação e se refere a um conjunto de características e atrasos no desenvolvimento de crianças nascidas de mães que consumiram álcool durante a gravidez (Yamaguchi et al, 2008;Momino, Sanseverino, & Schüler-Faccini, 2008).…”