Ethanol-induced reductions in cerebellar growth of infant rats.

Chronic ethanol consumption during gestation may adversely affect the developing human central nervous system (9, 10, 12). It is unknown, however, whether the pathologies result from circulating blood ethanol or from nutritional deficiencies and their consequences, since mothers bearing such children are generally malnourished. Morphological alterations in the developing cerebellar cortex produced by ethanol were investigated in the present study in infant rats during the period of cerebellar neurogenesis ( 1, 2). A vapor inhalation method was used which circumvents the damage caused to tissue when ethanol is administered by injection or the confounding factors of severe dehydration and malnutrition when mothers are forced to consume ethanol. Purdue-Wistar rats, cross-fostered and raised eight to a litter, inhaled an air mixture calculated to contain 3.5-4s (v/v) ethanol during two 90-min daily sessions from 3 to 20 days. The vapor mixture, monitored by a BSV 640 Matheson flowmeter, was forced into 0.015 cu m transparent chambers, the volumes of which were exchanged each min. Blood ethanol concentrations averaged 268 mg/lOO ml, as measured directly by gas chromatography from blood collected by cardiac puncture from unanesthetized rats at 5, 10, 15 and 20 days immediately after the second daily exposure to ethanol vapor. The animals were not unconscious at these blood levels; subjectively, however, younger animals appeared less active and older animals slightly ataxic immediately after ethanol treatment. Control rats were placed in identical chambers and similarly treated, but exposed only to air. 1 Aided by NIAAA and NICHHD predoctoral fellowships to the senior author and by an NIMH research grant. The authors thank Dr. F. W. Bauer, Jr., who conducted blind examinations on lung and liver tissues.