Changes in the Inducibility of a Hepatic Aldehyde Dehydrogenase

Rat liver contains at least two cytosolic aldehyde dehydrogenases (ALDH 1.2.1.3) which are inducible by inducers of drug metabolism (Deitrich, 1971; Marselos and Hanninen, 1974; Deitrich et al., 1977).Phenobarbital (PB) type inducers induce the φ-isozyme in certain rat strains with a genetic predisposition (RR) (Deitrich, 1971; Deitrich et al., 1972; Marselos, 1976; Nakanishi et al., 1978). Polycyclic aromatic hydrocarbons or other type II inducers of drug metabolism can induce another isozyme (τ-ALDH), an isozyme which has been detected in all rat strains tested to date (Deitrich et al., 1978; Marselos et al., 1979; Vasiliou et al., 1988). An increase in ALDH activity was also found in primary cultures of human or rat hepatocytes, after in vitro exposure to PB or methylcholanthrene (Marselos and Michalopoulos, 1986; Marselos et al., 1987).