Qualitative alterations in plasma esterases in BALB/c mice following the administration of diethylnitrosamine

Biochemical and genetic characterization of esterase-27 (ES-27), the major plasma cholinesterase of the house mouse (Mus musculus)

Esterase-27A (ES-27A) was characterized in strain A/WySnA by a cascade of seven bands seen after disc electrophoresis of serum and subsequent staining for esterase. ES-27A catalyses the hydrolysis of thiocholine butyrate and is strongly inhibited by 100 microM tetraisopropyl pyrophosphamide (isoOMPA). Hence, the enzyme was concluded to be a cholinesterase EC 3.1.1.8. A heat-labile form termed ES-27B was represented by strain AKR/Han. From a three-point cross (AKR/Han, A/Wy) and a five-point cross (AKR/Han, SEG/1), the gene order on chromosome 3 was concluded to be centromere-Car-2-Es-26-Es-27-Amy-1-Adh-1.

Effects of carcinogenic and non-carcinogenic chemicals on plasma esterases in BALB/c mice

Esterase profiles of plasma from female BALB/c mice treated with a variety of carcinogenic and weakly- or non-carcinogenic chemicals were analyzed. Mice treated with the potent carcinogens diethylnitrosamine, dinitrosopiperazine, dipropylnitrosamine, dimethylhydrazine, urethane, and dimethyldinitrosopiperazine had similarly altered plasma esterase profiles after 7 days' exposure to the chemicals. The alterations consisted of increased activity in 4 esterase bands. The increased activity persisted in some of the bands after cessation of carcinogen exposure. Exposure to high concentrations of the weakly- or non-carcinogenic compounds nitrosohydroxyproline, nitrosomethoxymethylamine, 1-nitroso-4methylpiperazine,nitroso-2,6dimethylpiperidine, and ethyl methanesulfonate caused no obvious plasma esterase alterations. Ingestion of carbon tetrachloride resulted in increased activity in one esterase band with concomitant decrease in a second band. Analysis of serum from test mice for levels of serum glutamic oxaloacetic transaminase, alkaline phosphatase, lactate dehydrogenase-lactate substrate, and D-gamma-glutamyl transpeptidase did not differentiate between mice treated with selected carcinogens and those treated with non-carcinogens and/or carbon tetrachloride.