Histochemical and biochemical detection of alcohol dehydrogenase in rat brown adipose tissue

Alcohol dehydrogenase (ADH) was studied histochemically in rat brown adipose tissue (BAT), white adipose tissue (WAT) and liver, and its activity was also measured in these tissues. A positive ADH reaction was seen histochemically in the liver and BAT, but not in the WAT, and similarly ADH activity was detected biochemically in the liver and BAT, but there was no measurable activity in the WAT. ADH activity was 80% higher in the liver than in the BAT. It is suggested that the occurrence of an ethanol metabolizing enzyme in brown adipose tissue may be connected with the previously reported ethanol-induced increase in the oxidative capacity of BAT, or, at least, that BAT is able to use ethanol as a substrate for thermogenesis.