Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Reactivation and Aging of Phosphorylated Brain Acetylcholinesterase from Fish and Rodents.
Author Wallace, K. B. ; Herzberg, U. ;
CORP Author Minnesota Univ.-Duluth. Dept. of Pharmacology.;Environmental Research Lab.-Duluth, MN.
Publisher c1988
Year Published 1988
Report Number EPA-R-810963; EPA/600/J-88/453;
Stock Number PB90-147364
Additional Subjects Brain ; Acetylcholinesterase ; Phosphorylation ; Aging(Biology) ; Toxicity ; Cholinesterase inhibitors ; Exposure ; In vitro analysis ; Rodents ; Aquatic animals ; Reprints ; Pharmacokinetics ; Dose-response relationships
Library Call Number Additional Info Location Last
NTIS  PB90-147364 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 06/15/1990
Collation 9p
Species-related differences in sensitivity to acute intoxication by anticholinesterase compounds have been attributed, in large part, to differences in the kinetics of inhibition of acetylcholinesterase (AChE) in vitro. Since inhibition of AChE is also influenced by the stability of the phosphorylated enzyme complex, it was of interest to compare the rates at which the inhibited enzyme from different species subsequently either reactivates or ages. Brain AChE from rats, mice, fathead minnows, or rainbow trout was preincubated with an IC90 concentration of either paraoxon or malaoxon. The first-order rate constants for both the reactivation and aging of paraoxon-inhibited AChE from rats and mice were significantly greater than those observed for either species of fish. Following malaoxon inhibition, however, rodent AChE reactivated more rapidly but aged more slowly than did the enzyme from minnows. Therefore, the data suggest that compared to rodents, intermittent or continuous exposure of fish to sublethal concentrations of anticholinesterase compounds is more likely to result in a cumulative toxicity owing to the relative irreversibility of AChE inhibition. (Copyright (c) 1988 Academic Press, Inc.)