Studies on alcohol metabolism Part I. Histochemical studies on alcohol dehydrogenase and aldehyde dehydrogenase in man and in animals

Histochemical staining methods for alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) were studied. Many reports on ADH staining have been documented, and in the current study the author attempted to stain cryostat-prepared tissue sections on the slide glass. The author studied the composition of the incubation medium, incorporating nitro-blue-tetrazolium (NBT) and the staining procedure. ALDH staining has been less documented, but the author obtained a satisfactory result by using a staining method basically the same as that for ADH, with disulfiram as the inhibitor. In vivo distributions of ADH activity were studied in man, rabbit, quinea pig, rat and mouse. The activity varied sagnificantly from species to species. It was the highest in the liver, and found in the mucous membrane of the digestive tract, lung, pancreas and kidney to a lesser extent. In addition, ALDH activity in man was striking, not only in the liver, but also in the lung and kidney. It was also found in the mucous membrane of the digestive tract. When changes in ADH activity were studied in rabbits orally fed with ethanol every other day for one year, no such findings could be confirmed.