Evaluation of the nature of camel retinal acetylcholinesterase: inhibition by hexamethonium

Dual substrate model for novel approach towards a kinetic study of acetylcholinesterase inhibition by diazinon

Limited reports as compared to other insecticides appear in the literature for acetylcholinesterase (AChE) inhibition by diazinon. In the current study, new kinetic parameters of AChE inhibition by diazinon have been investigated. The assay was done with bovine retinal AChE using two different substrate (ASCh) concentrations in the absence and presence of diazinon (0.08-1.28 mM). The optical density was monitored up to 25 min (reaction time) for the assay. New kinetic parameters k'(oms), K'(sms), k(oms), K(sms), K'(asms) and K(asms) ) were calculated from these experimental data.

Kinetic constants for the inhibition of camel retinal acetylcholinesterase by the carbamate insecticide lannate

We have designed this study to determine various kinetic parameters of camel retinal membrane-bound acetylcholinesterase (AChE; EC 3.1.1.7) inhibition by carbamate insecticide lannate [methyl N-[[(methylamino)carbonyl]oxy] ethanimidothioate]. All these kinetic constants were derived by simple graphical methods. The value of kinetic parameters was estimated as follows: 0.061 microM)(-1), 1.14 (microM)(-1), 0.216 microM, 0.016 min(-1), 0.0741 (gammaM min)(-1) 0.746 microM, and 4.42 microM for velocity constant (Kv), new inhibition constant (Knic), dissociation constant (Kd), carbamylation rate constant (k2c), overall carbamylation rate constant (k'2), 50% inhibition constant (K150), and 99% inhibition constant (K199), respectively. These unique methods may be used to estimate such kinetic parameters for time-dependent inhibition of enzymes by variety of chemicals, insecticides, herbicides, and drugs.