Validation of an electrometric blood cholinesterase measurement in goats.
- Author:
M MH AL-JOBORY
1
;
F K MOHAMMAD
Author Information
1. Department of Physiology, Division of Pharmacology and Toxicology, College of Veterinary Medicine, University of Mosul, Mosul, P. O. Box 11136, Iraq. fouadmohammad@yahoo.com
- Publication Type:Original Article ; Comparative Study ; Research Support, Non-U.S. Gov't ; Validation Studies
- Keywords:
carbaryl;
cholinesterase;
diazinon;
dichlorvos;
goat;
organophosphate
- MeSH:
Acid-Base Equilibrium/physiology;
Animals;
Carbaryl/pharmacology;
Cholinesterase Inhibitors/pharmacology;
Cholinesterases/*blood/drug effects;
Diazinon/pharmacology;
Dichlorvos/pharmacology;
Enzyme Activation/drug effects/physiology;
Erythrocytes/metabolism;
Goats/*blood;
Plasma/metabolism
- From:Journal of Veterinary Science
2005;6(4):299-303
- CountryRepublic of Korea
- Language:English
-
Abstract:
A modified electrometric method was described and validated for measurement of plasma and erythrocyte cholinesterase activities in 6~18 months old goats. The enzymatic reaction mixture contained 3 ml distilled water, 3 ml barbital-phosphate buffer (pH 8.1), 0.2 ml plasma or erythrocytes and 0.1 ml acetylthiocholine iodide (7.5%) as a substrate. The mixture was incubated at 37 degrees C for 40 minutes. The pH of the reaction mixture was determined by a pH meter before and after the incubation. The initial pH was measured before the substrate addition. The enzyme activity was expressed as deltapH/40 min. The coefficients of variation of the described method in measuring plasma and erythrocyte cholinesterase activities were 4 and 2%, respectively. Preliminary reference values (n = 14) of the mean cholinesterase activity (deltapH/40 min) and 95% confidence interval in the plasma were 0.194 and 0.184~ 0.204, respectively, and those of the erythrocytes were 0.416 and 0.396~0.436, respectively. The pseudocholinesterase activity of the plasma cholinesterase was 63.5% as determined by quinidine sulfate inhibition. The organophosphorus insecticides dichlorvos and diazinon at 0.5~4 micrometer and the carbamate insecticide carbaryl at 5~20 micrometer in the reaction mixture significantly inhibited plasma (13.7~85.5%) and erythrocyte (16.4~71.9%) cholinesterases in vitro in a concentration-dependent manner. The results suggest that the described electrometric method is simple, precise and efficient in measuring blood cholinesterase activity in goats.
