The 2-[14C] deoxyglucose (2DG) method was used to examine the effects of the acute, intragastric (IG) administration of ethanol on rates of local cerebral glucose utilization (LCGU) in male Sprague-Dawley rats. The 2DG technique was initiated 3 min after the administration of 0.25, 1.0, or 2.0 g/kg ethanol. Each dose of ethanol examined produced a discrete pattern of change in functional activity. The administration of 0.25 g/kg ethanol increased LCGU in structures of the mesocorticolimbic and nigrostriatal circuits. The administration of 1.0 and 2.0 g/kg ethanol, however, produced a more limited pattern of changes in LCGU, with increases observed primarily in the mesocorticolimbic circuit. The increases in functional activity observed after the administration of the 0.25 g/kg ethanol dose were more widespread, and generally of larger magnitude, as compared to the 1.0 and 2.0 g/kg ethanol doses. These data indicate that structures of the mesocorticolimbic system are particularly sensitive to the effects of both low and high doses of ethanol when the effects are measured on the ascending limb of the blood ethanol curve.