US EPA

2175496 

Book/Book Chapter 

Induction of cytoplasmic aldehyde dehydrogenases in rat tissues by carcinogenic and non-carcinogenic xenobiotics 

Koivusalo, M; Rautoma, P 

1985 

Alan R. Liss, Inc. 

New York 

Enzymology Of Carbonyl Metabolism 2: Aldehyde Dehydrogenase, Aldo-Keto Reductase, and Alcohol Dehydrogenase 

174 

101-112 

English 

3920673 

Rat liver has normally a very low aldehyde dehydrogenase activity in the cytoplasmic fraction comprising only 10-15 per cent of the total activity (Koivula, Koivusalo 1975). The cytoplasmic activity can, however, be strongly increased by administration of several exogenous compounds. Phenobarbital administration increases the activity but only in genetically-determined lines of rats (Deitrich et al. 1972) . Several other drugs and xenobiotics can also induce the cytoplasmic enzyme e.g. tetrachlorodibenzo-p-dioxin (TCDD), 3-methylcholantrene and benz(a)pyrene (Deitrich et al. 1977, 1978. Marselos et al. 1979). The induced enzymes have different properties from those of the normal cytoplasmic enzymes. The phenobarbital-induced enzyme has been purified and is found to be different from the other induced enzymes (Deitrich et al. 1977, Koivula, Koivusalo 1975, Torronen 1981). The TCDD-induced enzyme (Deitrich et al. 1977) and the enzymes induced by benz(a)pyrene, phenantrene (Torronen 1981) and by 2-acetamidofluorene (Koivula, Koivusalo 1982) have also been purified.

The cytoplasmic aldehyde dehydrogenase activity is also increased in several chemically induced rat hepatomas (Feinstein, Cameron 1972, Lindahl et al. 1982) and new aldehyde dehydrogenase isoenzymes are found, which resemble the enzymes induced by xenobiotics. The relations between chemical carcinogenesis and induction of rat liver cytoplasmic aldehyde dehydrogenase have been recently reviewed by Lindahl (1982). The appearance of certain isoenzyme types has been proposed to be linked to chemical carcinogenesis (Lindahl et al. 1982). The enzyme induced by the non-carcinogenic phenantrene has been found to be different from the enzyme induced by the carcinogenic benz(a)pyrene (Torronen 1981) and this led to the suggestion that carcinogenic and non-carcinogenic xenobiotics might generally induce different types of aldehyde dehydrogenase activity.

In the present investigation we have studied in short term experiments the induction of rat liver cytoplasmic aldehyde dehydrogenase activity by the carcinogenic 3-methylcholantrene (MC) and by the non-carcinogenic S-naphthoflavone (NF) and polychlorinated biphenyls (PCB). The induced enzymes have been purified and characterized and their properties compared. 

Flynn, TG; Weiner, H 

0845150243 

Second International Workshop on Aldehyde Dehydrogenase/Aldehyde Reductase/Alcohol Dehydrogenase 

Kingston, Ontario, Canada 

July 1-4, 1984