N-Nitrosobutyl(4-hydroxybutyl)amine alpha-hydroxylation by rat liver and urothelial cell homogenates.
Determination of molecular nitrogen formed as a consequence of nitrosamine alpha-hydroxylation provides a useful means for studying the extent of activation of these compounds in target and nontarget organs and tissues. alpha-Hydroxylation in rat liver and urothelial cells was compared using as substrate doubly 15N-labelled N-nitrosobutyl(4-hydroxybutyl)amine (15N-NBHBA), a potent bladder carcinogen in rodents. Both enzyme sources metabolized 15N-NBHBA through the alpha-hydroxylation pathway. 15N2 production was dependent on the amount of substrate incubated. Vmax values for 15N2 production by urothelial cells and by liver postmitochondrial supernatant were 4.47 and 3.21 nmol/mg protein per h, respectively.
Airoldi
L
L
Laboratory of Environmental Pharmacology and Toxicology, Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
Magagnotti
C
C
Bonfanti
M
M
Moret
M
M
Fanelli
R
R
D000818:Animals; D001711:Biotransformation; D002273:Carcinogens / Q000378:metabolism*; D004260:DNA Repair; D006900:Hydroxylation; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism*; D008297:Male; D009602:Nitrosamines / Q000378:metabolism*; D009928:Organ Specificity; D051381:Rats; D011919:Rats, Inbred Strains; D001743:Urinary Bladder / Q000378:metabolism*; D001749:Urinary Bladder Neoplasms / Q000139:chemically induced
D002273:Carcinogens; D009602:Nitrosamines