Journal of Dental Research, Vol 70, 1061-1063, Copyright © 1991 by International & American Associations for Dental Research Online Journals
Alteration in glutathione level during carcinogenesis of hamster buccal pouch mucosa
L. Zhang and D. Mock
Faculty of Dentistry, University of British Columbia, Vancouver, Canada.
This study examined the level of glutathione (GSH)--a tripeptide that may
have an important role in detoxification of carcinogens--in the hamster
buccal pouch mucosa (HBPM) by a 12-week regimen of tri-weekly topical
application of 7,12-dimethylbenz[a]anthracene (DMBA) in mineral oil. GSH
was quantified periodically and shown to be doubled in carcinogen-treated
vs. control pouch mucosa. In the tumors that developed, the level of GSH
was three times that of the controls. Previous studies showed that
gamma-glutamyl transpeptidase (GGT), one of the enzymes that may be
responsible for the detoxification of carcinogens, was increased in the
hamster mucosa pre-neoplastic foci, but decreased with the formation of
overt neoplasia. GGT and GSH are intimately related, since GGT is the only
enzyme that can cleave the intact GSH molecule. The increase in both GSH
and GGT levels may be responsible for the increased resistance of the
pre-neoplastic pouch epithelium to the toxic effects of the carcinogen.
