Effect of chronic ethanol consumption on aldehyde dehydrogenase activity in the baboon

Baboon liver has detectable aldehyde dehydrogenase (A1DH) activity in the mitochondrial, microsomal and soluble fractions. Based on kinetic data, the mitochondrial and soluble fractions each appear to contain two forms of A1DH, one with a high, and another with a low, K_m for acetaldehyde. In the microsomes there was activity only with millimolar concentrations of acetaldehyde. In the baboon liver, about 75 per cent of total A1DH activity resides in the mitochondria and 20 per cent in the soluble faction. Chronic ethanol consumption decreased total and low K_m mitochondrial A1DH activity in baboon liver. In rats, ethanol consumption also resulted in decreased mitochondrial low K_m A1DH activity.