Effects of short-term inhalation exposure to 1-nitropropane and 2-nitropropane on rat liver enzymes.
Male Sprague-Dawley rats were exposed to vapors of 1-nitropropane (1-NP) and 2-nitropropane (2-NP) at air concentrations of 100 ppm for 7 hours per day on four consecutive days. Livers were analyzed for enzymatic activities after 1-, 2-, and 4-day inhalation periods. Liver microsomal cytochrome P450 was depressed by 2-NP and elevated following exposure to 1-NP. Levels of cytochrome b5 were slightly increased in rats exposed to 1-NP and remained unchanged after inhalation of 2-NP. Total glutathione (GSH), GSH S-transferase, and UDP-glucuronosyltransferase activities were enhanced by 2-NP. 1-NP induced GSH peroxidase while 2-NP did not. Glutathione reductase was not altered after exposure to either isomer. No changes in the microsomal malondialdehyde content as a measure of lipid peroxidation and in the levels of serum aspartate transferase and serum glutamic oxaloacetic transaminase were observed during a 4-day exposure period in either of the exposed groups compared to control animals.
Haas-Jobelius
M
M
GSF-Forschungszentrum für Umwelt und Gesundheit GmbH, Institut für Okologische Chemie, Neuherberg, FRG.
Coulston
F
F
Korte
F
F
D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis; D005978:Glutathione / Q000032:analysis; D005982:Glutathione Transferase / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D009595:Nitroparaffins / Q000633:toxicity*; D011407:Propane / Q000031:analogs & derivatives* / Q000633:toxicity; D051381:Rats; D011919:Rats, Inbred Strains
D009595:Nitroparaffins; C035314:1-nitropropane; D003577:Cytochrome P-450 Enzyme System; D005982:Glutathione Transferase; D005978:Glutathione; C016617:2-nitropropane; D011407:Propane