Ethanol and tertiary butanol induced microcephaly in the neonatal rat: comparison of brain growth parameters.
Neonatal rats were reared using an artificial feeding technique from postnatal day 4 through 18. On Postnatal Days 4 through 7, corresponding to the onset of the brain growth spurt, some animals were administered either ethanol or tertiary butanol in the milk formula, with the remaining animals serving as controls. The alcohol dosages were equated to each other by membrane to buffer partition coefficients. Following the 4 day alcohol exposure, all animals were given the plain milk formula until Day 18, when they were decapitated and various organ weights measured. The only significant weight differences between alcohol-exposed animals and controls were absolute brain weights and brain weight/body weight ratios, which were decreased in both alcohol groups. Biochemical analysis of the brains showed similar DNA levels for the ethanol, tertiary butanol, and control group forebrain samples. Both alcohol groups had significantly lower DNA levels than the control group for the hindbrain samples. Cholesterol levels and cholesterol/DNA ratios indicated that ethanol, but not tertiary butanol, impaired myelination and/or arborization. Total protein and protein/DNA ratios suggested that ethanol interfered with protein production and/or incorporation. The tertiary butanol animals did not show this deficit. The results imply that while exposure to either alcohol during the brain growth spurt can lead to microcephaly, the ethanol-induced alteration of myelin formation and protein production in neonatal brain tissue may be due to additional properties of ethanol.
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001921:Brain / Q000187:drug effects* / Q000254:growth & development; D000440:Butanols / Q000494:pharmacology*; D002784:Cholesterol / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D008831:Microcephaly / Q000139:chemically induced*; D009115:Muridae; D009419:Nerve Tissue Proteins / Q000378:metabolism; D012018:Reflex / Q000187:drug effects; D020002:tert-Butyl Alcohol
D000440:Butanols; D009419:Nerve Tissue Proteins; D004247:DNA; D002784:Cholesterol; D020002:tert-Butyl Alcohol