Brain and liver aldehyde dehydrogenase: relations to ethanol consumption in Wistar rats. Neuropharmacology 16:781–784

Summary-Activity of brain and liver aldehyde dehydrogenase (ALDH) was measured in male Wistar rats given free access to ethanol and water for 50 days. Brain ALDH activity was better correlated with levels of absolute ethanol intake than liver ALDH, but the magnitude of the relations between enzyme activity and ethanol consumption varied depending on whether animals were regulating their ethanol consumption across different ethanol concentrations: brain and liver ALDH were better corre-lated with ethanol intake in regulating animals. By contrast, brain ALDH was relatively more important than liver ALDH in predicting ethanol consumption in non-regulating animals. The results suggest that brain and liver ALDH may mediate ethanol consumption in rats by regulating some aspects of the dose-effect relations between acetaldehyde and ethanol. There is increasing evidence to suggest that acetalde-hyde, the first product of ethanol oxidation, may mediate many of the effects of ethanol by interacting with metabolic processes in the brain (Truitt and Walsh, 1971; Rahwan, 1975). If the levels of acetalde-hyde in the brain is the physiological parameter tha