Accession Number : AD0763039

Title :   Pseudocholinesterases of Mammalian Plasma: Physicochemical Properties and Organophosphate Inhibition in Eleven Species,

Corporate Author : DALHOUSIE UNIV HALIFAX (NOVA SCOTIA) DEPT OF PHARMACOLOGY

Personal Author(s) : Ecobichon,D. J. ; Comeau,A. M.

Report Date : 03 APR 1972

Pagination or Media Count : 10

Abstract : The electrophoretic patterns, optimum pH, substrate specificity, Km values, rates of substrate hydrolysis and sensitivity to inhibition by (DFP) Disopropylfluorophosphate, paraoxon and (DDVP) dichlorvos were compared for the plasma pseudocholinesterases of the horse, man, mouse, guinea pig, dog, cat, rat, rabbit, swine, goat and hamster. The molecular heterogeneity of these enzymes was established. There were no significant differences in activity between sexes of the same species, except in the rat where the female had 4- to 10-fold higher activity than the male. Data presented as I50 values for the anticholinesterases showed that DFP was the most potent, paraoxon and DDVP being 10-fold and 100-fold less potent, respectively. With the exception of the rabbit, goat, hamster and swine, which were very resistant to DFP the inhibitor I50 values were quite similar despite the marked species variations in enzyme activity and specificity. (Author)

Descriptors :   (*CHOLINESTERASE, MAMMALS), ANIMALS, ENZYMES, CHEMICAL ANALYSIS, PHYSICAL PROPERTIES, ORGANIC PHOSPHORUS COMPOUNDS, INHIBITION, BLOOD PLASMA, NOVA SCOTIA

Subject Categories : Pharmacology

Distribution Statement : APPROVED FOR PUBLIC RELEASE