[Inhibition of aldehyde dehydrogenase activity in rat liver by cyclopropylethyl-containing benzoic acid amides]

Influence of cyclopropylethyl-containing benzoic acid amides on the aldehyde dehydrogenase activity of the rat liver mitochondria was investigated. Values of I50 were measured for each of the compounds. The character of kinetic behavior of these reversible inhibitors was studied. It is shown that 2,5-dichloro-4-methylbenzoic acid amides reveal partially uncompetitive type of inhibition relative to acetaldehyde, while 2,4-dichloro- and 2,4-dichloro-5-methylbenzoic acid amides reveal changes in the character of inhibition from uncompetitive to mixed one. Inhibition was partially competitive with regard to reaction NAD+ cofactor. Though the studied compounds induced inhibition of a certain type with respect to each of the substrates, but on the whole the mechanism promoting a decrease of the ALDH-1 reaction rate appears to be more complex.