SUSCEPTIBILITY OF BRAIN ALDEHYDE METABOLIZING ENZYMES TO PARGLYINE, DISULFIRAM AND DIETHYLMALEATE INVIVO IN RATS

In vivo susceptibility of mitochondrial (m)- and soluble (s)-aldehyde dehydrogenase (AlDH) and aldehyde reductase (AIR) to three compounds, i.e., pargyline, diethylmaleate and disulfiram in rat brain was studied. In all experiments using the compounds tested, m-AlDH was more significantly inhibited when the low concentration of the substrate (50 μM) was used, as compared with the inhibition of the enzyme in use of high substrate concentration (3.3 mM). Under same condition, little or no inhibition of s-AlDH and AIR was observed. These findings strongly suggest that there are at least two forms of AlDH with different Kms and they have different susceptibility to AlDH inhibitors. © 1979.