Main Title |
Effects of Age, Species Difference, Antibiotics and Toxicants on Intestinal Enzyme Activity and Genotoxicity. |
Author |
Chadwick, R. W. ;
George, S. E. ;
Chang, J. ;
Kohan, M. J. ;
Dekker, J. P. ;
|
CORP Author |
Health Effects Research Lab., Research Triangle Park, NC. ;North Carolina Univ. at Chapel Hill. ;Environmental Health Research and Testing, Inc., Research Triangle Park, NC. |
Publisher |
1993 |
Year Published |
1993 |
Report Number |
EPA/600/J-94/021; |
Stock Number |
PB94-137338 |
Additional Subjects |
Mutagens ;
Intestines ;
Antibiotics ;
Toxic substances ;
Enzymes ;
Aging(Physiology) ;
Species diversity ;
Metabolic activation ;
Gas chromatography ;
Environmental carcinogens ;
Reprints ;
|
Holdings |
Library |
Call Number |
Additional Info |
Location |
Last Modified |
Checkout Status |
NTIS |
PB94-137338 |
Some EPA libraries have a fiche copy filed under the call number shown. |
|
07/26/2022 |
|
Collation |
16p |
Abstract |
Altered intestinal enzyme activity significantly affects the biotransformation and toxicity of many xenobiotics. This article summarizes research that employs a novel gas-liquid chromatographic assay to investigate the effects of age, species difference, antibiotics, and environmental chemicals on enzyme activity in various regions of the intestinal tract. Significant research findings include the following: (a) age-dependent alterations in enzyme activity in the gastrointestinal (GI) tract of the developing animal that suggest a changing susceptibility to toxicants during this period; (b) discovery of previously unreported mucosal enzymes in the small intestine that are present in germ-free rats and are not susceptible to antibiotics; (c) markedly greater intestinal nitroreductase activity and significantly higher bioactivation of the procarcinogen 2,6-dinitrotoluene (DNT) in CD-1 mice than in Fischer 344 rats; (d) significantly altered intestinal enzyme activity in rats pretreated with lindane, pentachlorophenol, 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), or Aroclor 1254; (e) potentiated DNT genotoxicity by Aroclor 1254 and pentachlorophenol pretreatment; and (f) a transient antagonism of DNT genotoxicity by 2,4,5-T pretreatment. Enzyme activity in the small intestine may have greater toxicological importance than previously thought in the biotransformation of environmental chemicals and as an indicator of change in the microbial flora. |
Supplementary Notes |
Pub. in Environmental Toxicology and Chemistry, v12 n8 p1339-1352 Aug 93. Presented at the Symposium on U.S. Air Force Bioenvironmental Research Annual Meeting (11th), Society of Environmental Toxicology and Chemistry, Arlington, VA., November 11-15, 1990. Prepared in cooperation with North Carolina Univ. at Chapel Hill, and Environmental Health Research and Testing, Inc., Research Triangle Park, |
NTIS Title Notes |
Journal article. |
Title Annotations |
Reprint: Effects of Age, Species Difference, Antibiotics and Toxicants on Intestinal Enzyme Activity and Genotoxicity. |
Category Codes |
57Y; 57F; 57S |
NTIS Prices |
PC A03/MF A01 |
Primary Description |
600/10 |
Document Type |
NT |
Cataloging Source |
NTIS/MT |
Control Number |
407720088 |
Origin |
NTIS |
Type |
CAT |